July 17-21, 2007
St. Petersburg, FL USA

PROGRAM AND
ABSTRACT BOOK

July 17-21, 2007 z St. Petersburg, Florida USA

Welcome to the 1st International Sclerochronology Conference
organized by the University of Florida/IFAS and its partners, The Florida
Museum of Natural History, Florida Sea Grant Program, and the Fish andWildlife Research Institute.
In April 2005 the Center for Coastal Studies of the United States Geological
Survey office in St. Petersburg convened a “clam bake” workshop to discuss
sclerochronological issues regarding the hard clam Mercenaria. The organizersof this workshop, Terry Edgar and Carole McIvor, invited scientists from various
disciplines to discuss the potential for using Mercenaria shells to unravel historic patterns of pollutant load
development in the Tampa Bay estuarine system. Among the attendees were Bill Arnold, Doug Jones, Irv
Quitmyer, and Donna Surge, and it was upon our departure from that meeting that we first discussed the ideaof expanding the clam bake to an international meeting focused on the science of sclerochronology in all its
many manifestations. Thus, it is appropriate that the first of what we hope will be a continuing series ofmeetings is being held here in St. Petersburg.
With no precedent upon which to build, we chose to solicit participation from anyone remotely interested in
the field of sclerochronology. That field, as defined by us with regard to this meeting, includes the study ofphysical and chemical variations in the accretionary hard tissues of organisms, and the temporal context inwhich they formed. Sclerochronology focuses primarily upon growth patterns reflecting annual, monthly,
fortnightly, tidal, daily, and sub-daily increments of time entrained by a host of environmental andastronomical pacemakers. Familiar examples include daily banding in reef coral skeletons or annual growthrings in mollusk shells. Sclerochronology is analogous to dendrochronology, the study of annual rings in trees,and equally seeks to deduce organismal life history traits as well as to reconstruct records of environmental andclimatic change through space and time. Our goal was to bring together representatives from the many topicaland systematic branches of sclerochronology, and we are very pleased with the degree to which we haveachieved that objective.
Social interactions are always important at such gatherings, and St. Petersburg in the summer offers many
entertainment options including restaurants, bars, theatres, and museums in the downtown area, the major
league baseball Tampa Bay Devil Rays, and of course the beautiful beaches and waterways of Florida. We
hope that you have the time and opportunity to enjoy these many attractions, and we anticipate that the many
cultural opportunities available in the local area serve to initiate and strengthen bonds among peers.
The success of this meeting reflects the essential contributions of both our sponsors and our conference
coordinators. Those generous sponsors include the Florida Sea Grant College Program, the Florida Museumof Natural History, the Georgia Sea Grant College Program, the United States Geological Survey, and Buehler
Incorporated. Our lead conference coordinator, Sharon Borneman, not only made the meeting possible but
made it as easy as such a task could be for the organizing committee that included ourselves, Irv Quitmyer,
Donna Surge, and Bernd Schöne. We thank them all, and we thank you for taking the time to attend andcontribute.
Conference Co-Organizers,

Bill Arnold

Doug JonesiFirst International Sclerochronology ConferenceiiJuly 17-21, 2007 z St. Petersburg, Florida USA

Table of Contents

Welcome Letter ...........................................................................i
Organizing Committee ...............................................................v
Sponsor Recognition ................................................................ vii
Program Agenda .......................................................................ix
Directory of Poster Presentations.............................................xv
Conference Abstracts................................................................ 1
Author Index.......................................................................... 113
Notes..................................................................................... 116

iii

First International Sclerochronology ConferenceivJuly 17-21, 2007 z St. Petersburg, Florida USA

Organizing Committee
Bill Arnold, Conference Co-Chair
and Conference Organizer
Research Scientist
Fish and Wildlife Research Institute100 Eighth Avenue SE
St. Petersburg, FL USA

Irvy Quitmyer
Florida Museum of Natural History
Environmental Archaeology Laboratory
Dickinson Hall - Museum Road
University of Florida
Gainesville, FL USA

Douglas S. Jones, Conference Co-Chair
and Conference Organizer
Director, Florida Museum of Natural History
University of Florida - Museum Road
Gainesville, FL USA

Bernd R. Schöne
Department of Applied and Analytical
Paleontology and INCREMENTS Research Group,
Institute of Geosciences
University of Mainz
55128 Mainz, GERMANY

Sharon Borneman
Conference Coordinator
University of Florida/IFAS
Office of Conferences & Institutes
Mowry Road Building 639
Gainesville, FL USA

Donna Surge
Department of Geological Sciences
University of North Carolina
CB #3315, 225 Mitchell Hall
Chapel Hill, NC USAv

First International Sclerochronology ConferenceviJuly 17-21, 2007 z St. Petersburg, Florida USA

A Special Thank You to Our Conference Sponsors
BuehlerFlorida Fish and Wildlife Conservation Commission
Fish and Wildlife Research Institute

Florida Museum of Natural History
Florida Sea Grant
Georgia Sea Grant
University of Florida / IFAS
US Geological Survey
Greater Everglades Priority Ecosystem Science (PES)vii

First International Sclerochronology ConferenceviiiJuly 17-21, 2007 z St. Petersburg, Florida USA

Program Agenda
Abstract page numbers are indicated at the end of listings when applicable [example: “…(p. 2)”]

Tuesday, July 17, 2007 - Arrival & Check-in
4:00pm-6:00pm

Conference Registration Opens and Early Bird Social

Wednesday, July 18, 2007
7:00am-5:00pm

Conference Registration Open

7:30am-8:30am

Continental Breakfast

9:00am-10:00am

Welcome & Introductory Remarks

10:00am-10:30am

Refreshment BreakGeneral Session I - 10:30am-12:30pm
Moderator - Bernd Schone
10:30am-10:50am

Daily Microgrowth Bands in Bivalve Shells; Where is the Evidence?
– Christopher Richardson (p. 89)

10:50am-11:10am

Subdaily and Hourly Growth Patterns within the Shell of theChilean Gastropod Concholepas concholepas: New Perspectives forHigh-Resolution Sclerochronological Studies – Nury Guzman (p. 40)

11:10am-11:30am

Reality and Ilusion in Interpretation of Daily Growth Increments in
Cephalopod Statoliths and Fish Otoliths – Alexander Arkhipkin(p. 4)

11:30am-11:50am

Isotope Sclerochronology and Season of Annual Growth Line
Formation of the Limpet Patella vulgata from Spain and Norway –Donna Surge (p. 97)

11:50am-12:10pm

Advances in Sample Preparation for Bivalve Growth Increment
Studies – Robert Cerrato (p. 19)

12:10pm-12:30pm

Annual Growth Bands in the Carboniferous Brachiopod
Gigantoproductus: A High-resolution Stable Isotope andSclerochronology Study – Ethan Grossman (p. 39)

12:30pm-2:00pm

Lunch on Own

General Session II - 2:00pm-4:00pm
Moderator - Donna Surge
2:00pm-2:20pm

Changing Growth Rate and Growth Pattern of the Northern Quahog,
Mercenaria mercenaria, in Narragansett Bay, RI (USA): A Tug ofWar between Increasing Water Temperature and Decreasing
Chlorophyll Concentration – Kelly Henry (p. 45)ix

First International Sclerochronology Conference

Wednesday, July 18, 2007 (continued)
2:20pm-2:40pm

Isotopic Records of Geoduck Shells and Environmental Changes in
Hood Canal – Yongwen Gao (p. 29)

2:40pm-3:00pm

Coral Skeletal Records of Heavy Metal Pollution from the
Mesoamerican Reef – Jessica Carilli (p. 13)

3:00pm-3:20pm

Use of Nitrogen Stable Isotopes in shell from Mercenaria
mercenaria to Trace Wastewater Inputs from Watershed to
Estuarine Ecosystems through Time – Ruth H. Carmichael (p. 14)

3:20pm-3:40pm

Historical and Geographic Trends in the d15N Sewage Signal
Encoded in Florida and Bahamas Gorgonians – Mike Risk (p. 92)

3:40pm-4:00pm

Coral Growth Records and their Relationship to Freshwater
Discharge in Southeast Florida – Kevin Helmle (p. 43)

5:00pm-7:00pm

Welcome Reception

Thursday, July 19, 2007
7:00am-5:00pm

Conference Registration Open

7:00am-8:00am

Continental Breakfast

General Session III - 8:00am-10:00am
Moderator - William Arnold
8:00am-8:20am

Sclerochronological and Geochemical Constraints on the Timing ofBiological Invasions – David Goodwin (p. 35)

8:20am-8:40am

Use of Trace Elemental Fingerprinting to Determine Larval
Connectivity in Southern California Mussel Populations – Pat
McMillan (p. 79)

8:40am-9:00am

How to Decode Individual Fish Movements Archived by Fish
Otoliths? A Bayesian Perspective. – Ronan Fablet (p. 25)

9:00am-9:20am

Intra-bone Oxygen Isotope Seasonality Patterns - A Promising New
Approach for Vertebrate Skeletochronology? – Thomas Tütken
(p. 102)

9:20am-9:40am

Incremental Growth of Fossil Lamnoid Shark Vertebral Centra –Bruce MacFadden (p. 75)

9:40am-10:00am

Determing the Individual Ages and Growth of Modern and EoceneOligocene Tortoises (Reptilia: Testudines) Using Skeletochronology– Dana Ehret (p. 23)

10:00am-10:30am

Refreshment Breakx

July 17-21, 2007 z St. Petersburg, Florida USA

Thursday, July 19, 2007 (continued)
General Session IV - 10:30am-12:30pm
Moderator - Irv Quitmyer
10:30am-10:50am

Stable-Isotope and Microgrowth-Increment Variation in Shells of
the Queen Scallop from Cool- and Warm-Temperate Settings –Andrew Johnson (p. 56)

10:50am-11:10am

Episodic Variability in Elemental Concentrations as a Potential
Aging Tool in Deep-Water Gorgonians (Keratoisis spp):
Comparisons with Radiometric and Morphological Age Estimators –Ronald Thresher (p. 101)

11:10am-11:30am

Isotopic Evidence for Variable Climate and Longevity in Modern
and Archaeological Coquina Clams, Donax variabilis, from
Northeast Florida – Douglas Jones (p. 58)

11:30am-11:50am

Primary Isotope Ratios Preserved in a Late Permian Bivalve Allow
for Life History and Paleoenvironmental Reconstructions – Linda
Ivany (p. 54)

11:50am-12:10pm

Seasonality in the North Sea during Selected Climate Transitions(Allerod and Late Medieval Climate Optimum) - Bivalve
Sclerochronology (Arctica islandica) – Bernd R. Schöne (p. 94)

12:10pm-12:30pm

The Seasonal Timing of Annual Growth Increments in the Shells of
the Bivalve Arctica islandica (ocean quahog): A Circum North
Atlantic Perspective using Oxygen Isotopes – Alan Wanamaker(p. 105)

12:30pm-2:00pm

Lunch on Own

General Session V - 2:00pm-4:00pm
Moderator - Douglas Jones
2:00pm-2:20pm

Growth Rate Patterns in Trachycardium procerum (Mollusca) Shells
from Coastal Peru and Relationships with ENSO-Related
Environmental Parameters – Marc Gosselin (p. 37)

2:20pm-2:40pm

Do Fossil Bivalve Shells From Seymour Island (Antarctic
Pennisula) Provide Evidence for Eocene El Nino? – Thomas Brey(p. 9)

2:40pm-3:00pm

High Latitude Climate Variability and Its Effect on FisheryResources as Revealed by Fossil Otoliths – Audrey Geffen (p. 30)

3:00pm-3:20pm

Constructing Growth Chronologies from Long-lived Bivalves: Have
We Got it Right? – Christopher Richardson (p. 88)

3:20pm-3:40pm

Recent Atlantic and Fossil Mediterranean Acesta spp. Bivalves as
Environmental Archives for the Deep-sea – Matthias López-Correa(p. 72)xi

First International Sclerochronology Conference

Thursday, July 19, 2007 (continued)
3:40pm-4:00pm

Antipatharians: High Resolution Recorders of the Oceanographic
Environment – Charles Holmes (p. 50)

4:00pm-6:00pm

Poster Session & Social

Friday, July 20, 2007
7:00am-5:00pm

Conference Registration Open

7:00am-8:00am

Continental Breakfast

General Session VI - 8:00am-10:00am
Moderator - Bernd Schone
8:00am-8:20am

Incremental Growth in a Deep Sea Hydrocoral – Fred Andrus (p. 3)

8:20am-8:40am

Microstructural and Geochemical Patterns at the Nyctemeral Scalein the Concholepas concholepas (Gastropoda) Shell – Claire
Lazareth (p. 69)

8:40am-9:00am

Shell Formation in Mytilus edulis: Interactive Effects ofTemperature, Salinity and Food Availability – Ute Kossak (p. 66)

9:00am-9:20am

Diary of a Bluegill: Daily d13C and d18O Records in Otoliths by
Ion Microprobe – Brian Weidel (p. 107)

9:20am-9:40am

Shell Architecture and Stable Isotope Signature of a Giant Deep-Sea
Oyster (Azores Archipelago) – Max Wisshak (p. 111)

9:40am-10:00am

An Innovative Laser Analytical Method for Data Records fromMussel Shells – Peter Bisling (p. 6)

10:00am-10:30am

Refreshment BreakGeneral Session VII - 10:30am-12:30pm
Moderator - Donna Surge
10:30am-10:50am

Cod Otoliths & Indicators of Phenology and Endogeny? – Sophy
McCully (p. 78)

10:50am-11:10am

Varying Growth Rates in Bamboo Corals: Sclerochronology andRadiocarbonDating of a Mid-Holocene Deep-Water Gorgonian
Skeleton from Chatham Rise (New Zealand) – Sibylle Noe (p. 85)

11:10am-11:30am

Sclerochronology Study of Ruditapes philippinarum Shell – Céline
Poulain (p. 87)

11:30am-11:50am

Using Dendrochronology Techniques for Age Determination andValidation of Ring Counts for Northern B.C. Geoduck Clams(Panopea abrupta) – Darlene Gillespie (p. 32)

xii

July 17-21, 2007 z St. Petersburg, Florida USA

Friday, July 20, 2007 (continued)
11:50am-12:10pm

History and Applications of Ageing Living Marine Resources at theNortheast Fisheries Science Center – Richard S. McBride (p. 77)

12:10pm-12:30pm

Application of Tree-Ring Techniques across Diverse Taxa andEcosystems in the Pacific Northwest, USA – Bryan Black (p. 7)

12:30pm-2:00pm

Lunch on Own

General Session VIII - 2:00pm-3:40pm
Moderator - Irv Quitmyer
2:00pm-2:20pm

Population Genetics of Mercenaria in Florida: Patterns and the
Influence of Scientific and Aquaculture Activities – William Arnold(p. 5)

2:20pm-2:40pm

Ambient Temperatures, Metabolic Stress and Otolith Increment
Formation in North Sea cod (Gadus morhua L.) – Andrew Harwood(p. 42)

2:40pm-3:00pm

Characterization and Quantification of Organic and Mineral
Contents of Fish Otoliths using Micro-Raman Spectrometry:
Application to European Hake – Aurelie Jolivet (p. 57)

3:00pm-3:20pm

Cathodoluminescence Sclerochronology of Mollusc Shells: A Tool
for Seasonal Contrasts Estimate Through Geological Time – Franck
Lartaud (p. 67)

3:20pm-3:40pm

Population Parameters from Size-Frequency Analysis Using aConstrained Maximum Likelihood Method – Robert Cerrato (p. 20)

3:40pm-4:00pm

Refreshment BreakGeneral Session IX - 4:00pm-5:00pm
Moderator - Douglas Jones
4:00pm-4:20pm

Reconstructing 20th Century SST Variability in the Southwest
Pacific: A Replication Study Using Multiple Coral Sr/Ca Records
from New Caledonia – Kristine DeLong (p. 21)

4:20pm-4:40pm

Holocene and Last Interglacial Paleoceanography in the Pacific
Subtropical Gyre from Coral Annual Bands of Okinotori-shimaIsland, Northwestern Subtropical Pacific Ocean – Hajime Kayanne(p. 59)4:40pm-5:00pm

Sclerochronolgical Studies and d18O Analyses on Modern and
MSA Opercula of Turbo Sarmaticus from the Southern Coast ofSouth Africa. – Mariagrazia Galimberti (p. 28)

5:00pmDinner on Own

xiiiFirst International Sclerochronology Conference

Saturday, July 21, 20071
7:30am-12:00pm

Conference Registration Open

7:30am-8:30am

Continental Breakfast

General Session X - 10:00am-11:20am
Moderator - William Arnold
10:00am-10:20am

Age and Growth of the Patagonian Scallop Zygochlamys patagonica(King and Broderip, 1832) Using a New Technique on the Hinge
Ligament – Paul Brickle (p. 10)

10:20am-10:40am

Environmental Controls on a Unique Siderastrea Coral Morphology– Jennifer Sliko (p. 95)

10:40am-11:00am

Changes in Gape Frequency and Thermal Tolerance in the
Freshwater Bivalves Anodonta cygnea and Margaritifera falcata –David Rodland (p. 93)

11:00am-11:20am

Temperature and Salinity Relationships from Bivalve Shell
Carbonate Using Calcium and Stable Isotope Ratio Profiles –Dorothee Hippler (p. 48)

11:20am-12:00pm

Break and Remove Posters

12:00pm-2:00pm

Awards Lunch and Meeting Summary

2:00pmConference Concludes

xivJuly 17-21, 2007 z St. Petersburg, Florida USA

Directory of Poster Presentations
Abstract page numbers are indicated at the end of listings when applicable [example: “…(p. 2)”]
PosterNumber1

Paleoenvironmental and Sclerochronologogic Reconstruction of Large Oyster-Bearing
Pliocene Reefs from Curacao – Amanda Booth (p. 8)2Growth Increment Analysis as an Archaeological Measure of Shellfish Collection Intensity –Meghan Burchell (p. 11)

3

A 150-year Chronology Using Growth Increments in the Shell of Arctica islandica from the
Irish Sea – Paul Butler (p. 12)

4

Calcification Rate of Montastraea Coral Species Growing Under Thermal Stress – Juan P.
Carricart-Ganivet (p. 15)

5

Arctic Bivalves as Proxies of Local and Large-scale Climatic Variations: Analysis of panArctic growth patterns – Michael Carroll (p. 16)

6Complimentary Oxygen and Hydrogen Isotopic Records of Fluvial Conditions in the Shells ofFreshwater Bivalves – Monica Carroll (p. 17)

7

Elemental Records of River Variation in the Shells of Freshwater Bivalves – Monica Carroll(p. 18)8

Shell Microstructure of Ocean Quahog, Arctica islandica: Past and present – Elena Dunca(p. 22)

9

Recording Paleoenvironmental Conditions by Mollusc Shells Using Cathodoluminescence andStable Isotope Sclerochronology – Laurent Emmanuel (p. 24)

10

Otolith Morphogenesis Analysis: An automated computer vision framework – Ronan Fablet(p. 26)

11

Mg/Ca Ratios in Marine Bivalve Shell Calcite: Evidence for a weak temperature control,
strong species-specific variation and significant small-scale compositional heterogeneity –Pedro Freitas (p. 27)

12

Oxygen Isotope Variation in Relation to Opaque and Translucent Bands in European hake
(Merluccius merluccius) Otoliths; Comparison between High Resolution Mass Spectrometry
and Ion Probe (SIMS) Techniques – Audrey Geffen (p. 31)

13

Periodic Endolithic Algal Blooms in Montastrea faveolata Corals – Jessie Godfrey (p. 33)

14

Seasonal Variations Preserved in an Extinct Neogene Scallop, Chesapecten, from Florida to
Delaware, USA – Ann Goewert (p. 34)

15

Reconstructing Intra-Annual Growth in Bivalve Mollusks: A mathematical approach – David
Goodwin (p. 36)

16

Improvement of Image Analysis for Sclerochronological and Paleo-Environmental Studies on
Mollusc Shells and Fish Otoliths – Marc Gosselin (p. 38)

17

Influence of Sea Temperature Variability on Shell Microstructural Growth of Concholepas
concholepas (Gastropoda) in Southern Peru – Nury Guzman (p. 41)

21

Examining Environmental Variation in a Norwegian High-Arctic Fjord: Evidence from
Serripes groenlandicus (Bivalvia) Growth Rates and Carbon Isotope Composition – Gregory
Henkes (p. 44)

xv

First International Sclerochronology Conference

PosterNumber18

Temperature and Salinity Relationships from Bivalve Shell Carbonate Using Calcium andStable Isotope Ratio Profiles – Dorothee Hippler (p. 48)

19

The Microstructure of Bivalve Shells: New insights from the ocean quahog Arctica islandica –Dorothee Hippler (p. 47)

20

The Effect of Early Meteoric Diagenesis on the Ca-Isotope System: A Case Study from
Altered Holocene/Pleistocene Bivalves (Gulf of Corinth Area, Greece) – Dorothee Hippler(p. 46)22

Stable Isotopes in Unstable Environments: Probing In Situ Environmental Conditions of
Zebra and Quagga Mussels – Erik Hoffmann (p. 49)

23

Assessing Environmental Factors Associated with Changes in the Growth Rate of Semele
casali through the Holocene – John Huntley (p. 51)

24

Recent Salinity Change in the Western Pacific Warm Pool Reconstructed by Coral Paleosalinometer – Hiroko Iijima (p. 52)

25

Looking Younger While Getting 'Colder': Exploring the Role of Heterochrony in the
Evolution of Long-Lived Bivalves from the Eocene of Seymour Island – Linda Ivany (p. 53)

26

Geographic Variation in Growth Rate and Form of a Jurassic Oyster, and its Environmental
Implications – Andrew Johnson (p. 55)

27

Stable Isotope Profiles of Fossil Molluscs from the Lower Pleistocene Seoguipo Formation(Korea) and Paleoseasonality Variation – Boo-Keun Khim (p. 61)

28

High-resolution Isotope Profiles of Walleye Pollack (Theragra chalcogramma) Otoliths fromthe East Sea: Tracing Habitat Environmental Conditions – Boo-Keun Khim (p. 60)

29

Modeling Oxygen-Isotope Ratios in an Estuarine Bivalve, Saxidomus gigantea: Insights into
Holocene Climate Change in Coastal British Columbia, Canada – Andrew Kingston (p. 62)

30

Source Effects on the Carbon-Isotope Variation in an Estuarine Bivalve, Saxidomus gigantea– Andrew Kingston (p. 63)

31

Trace Element Mapping of Otoliths by Laser Ablation ICP-MS: Transportation, Migration
and/or Vaterite? (And a Good Look at the Methods) – Alan Koenig (p. 65)

32

A Marine Carbonate Reference Material for Microanalysis – Alan Koenig (p. 64)

38

High-resolution Calibration of Geochemical Proxies in the Shell of a Laboratory Grown
Giant Clam (Tridacna squamosa) – Claire Lazareth (p. 68)

33

ENSO, Eastern Tropical Atlantic Temperature Anomalies and Coral Growth – Carlos Lentini(p. 70)34

Hydrothermal Vent Mussels as Recorders of Environmental Change – Jitka Libertinova (p. 71)

35

Southern Ocean Limpets as Potential High-resolution Environmental Archives – Matthias
López-Correa (p. 73)

36

Stable Isotopes (d18O & d13C), Trace and Minor Element Compositions of Recent Lophelia
pertusa Deep-Water Corals in the Ionian Sea (Mediterranean Sea) – Matthias López Correa(p. 74)37

xvi

Cross-dating: A Practical Application to Verify Historical Age Data for British Columbia
Geoduck (Panopea abrupta) – Shayne MacLellan (p. 76)

July 17-21, 2007 z St. Petersburg, Florida USA

PosterNumber
39

Environmental Controls on Daily Shell Growth of Phacosoma japonicum (Bivalvia:
Veneridae) from Japan – Tsuzumi Miyaji (p. 80)

40

Micro-scale Elemental Distribution in a Shell of the Venerid Bivalve Phacosoma japonicum –Tsuzumi Miyaji (p. 81)

41

Relationships between Fish and Otolith Sizes and Impact on Growth Patterns – Kristen Munk(p. 82)42

Indian Ocean Dipole Index for the Last 100 Years Recorded in Kenyan Coral Annual Bands –Nobuko Nakamura (p. 83)43

Microstructure, Growth Banding and Age Determination of a Primnoid Gorgonian Skeleton(Octocorallia) from the Late Younger Dryas to Earliest Holocene of the Bay of Biscay –Sibylle Noe (p. 84)

44

Schlerochronology in Massive Corals: Advantages and Disadvantages – Timothee Ourbak(p. 86)45

Gastropod Statoliths: A Tool for Reconstructing the Growth of Gastropods – Christopher
Richardson (p. 90)

46

Seawater Temperature Reconstruction from Annual Growth Increments in the Shell of
Pliocene Arctica Islandica from the Coralline Crag (UK) – Christopher Richardson (p. 91)

47

Estimating Growth Rates of Loggerhead Sea Turtles (Caretta caretta) Using Skeletal GrowthMarks – Melissa Snover (p. 96)

48

In Situ Growth Experiment of a Deep-sea Cold Seep Mollusk Using a New Growth Chamberwith Fluorochrome Calcein – Yohei Tada (p. 98)

49

Iron and Zinc in Mytilus edulis Shells Reflect Improved Water Quality in Boston Harbor,
Massachusetts – Renee Takesue (p. 99)

50

Mid-Pliocene Environments in the Eastern U.S. Gulf Coast: A study of stable isotopes andgrowth increments in the gastropod Conus adversarius – Kai Tao (p. 100)

51

Statistical and Spectral Analysis of Growth Increments in Freshwater Mussels, Switzerland –Séverine Vancolen (p. 103)

52

The Chemistry of Freshwater Mussels as a Proxy for Late Holocene River Conditions in the
Netherlands – Emma Versteegh (p. 104)53

Extracting Paleoenvironmental and Paleoclimate Information from Mercenaria campechiensis
Shells Dating to the Vandal Minimum, Coastal Southwest Florida, USA – Ting Wang (p. 106)54

Growth Patterns in the Littoral Mollusk Donax variabilis – Kelley Whatley (p. 108)55

Growth Patterns and Storm Surge Effects in the Estuarine Mollusk Rangia cuneata – Kelley
Whatley (p. 109)

56

How Continuous is the Data Recorder in Mollusk Shells? A case study of Chione cancellata
from Florida Bay – G. Lynn Wingard (p. 110)xvii

First International Sclerochronology ConferencexviiiConference Abstracts
Listed alphabetically by presenting author.
Presenting author names appear in bold.

1

First International Sclerochronology Conference2

July 17-21, 2007 z St. Petersburg, Florida USA

Incremental Growth in a Deep Sea Hydrocoral
C. Fred T. Andrus1, Christopher S. Romanek2 and George R. Sedberry3
1

Department of Geological Sciences, University of Alabama, Tuscaloosa, AL, USA
Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA
3
Marine Resources Research Institute, South Carolina Department of Natural Resources, Charleston, SC, USA
2

The timing and causes of incremental growth in deep marine organisms are often difficult toassess due to a combination of lack of time-series environmental data, knowledge of the natural
history of the organisms, and difficulty in field collection and observation. One method used tocircumvent these problems is to rely on skeletal geochemical profiles that serve as proxies forenvironmental and/or biological variables. This approach is complicated in deep water corals due
to irregular offsets from oxygen isotope equilibrium with seawater. Here we present datacomparing carbon (δ13C) and oxygen (δ18O) isotope and elemental profiles to incremental
growth in an aragonitic styrlasterid coral.
Colonies of Stylaster erubescens (Cnidaria: Hydrozoa) were collected from the Charleston Bump
(North Atlantic, NW Blake Plateau) using submersible from depths ranging from 400 to 600 m.
The Charleston Bump is an area of steep relief that disrupts the Gulf Stream off of the Carolinas,
USA, creating upwelling of the Charleston Gyre. The Bump rises from 700 to 400 meters below
the surface, in a series of scarps and ramps. This is a comparatively dynamic environment
relative to other deep water coral habitats. Currents at the Bump are strong, ranging during thefield collections from 0.6-0.8 m/s. Temperatures varied over the dive areas from 8.5-14°C.
Bottom water δ18O values ranged from 0.6-1.1‰. It is not known precisely how theseenvironmental parameters vary seasonally or inter-annually, however Gulf Stream dynamics
vary at multiple time scales, including seasonally, and would likely change local conditions on
the Charleston Bump.
δ13C and δ18O profiles measured perpendicular to growth increments oscillate in a generally
sinusoidal fashion. In some portions of a colony, isotope maxima and/or minima often occur at
contacts between increments, whereas in other parts of the colony there does not seem to be suchconsistent relationship. Elemental profiles are more variable and rarely oscillate sinusoidally orin tandem with increments. The variables that control these geochemical distributions are notwell understood, but the data suggest that the corals grow in oxygen isotope equilibrium (oruniformly offset from it) with seawater. Oxygen isotope-based estimates of temperature ranges,
assuming equilibrium conditions, are similar to observed temperatures at the collection site, but
environmental data are not adequate to conclusively determine this. It is therefore likely that theincrements and isotope distributions are functions of environmental variability, thus stylasteridcorals may represent untapped archives of past environmental conditions.
Contact Information: C. Fred T. Andrus, Department of Geological Sciences, University of Alabama, Tuscaloosa,
AL, USA, 35487, Phone: 205-348-5177, Fax, 205-348-0818, Email: fandrus@geo.ua.edu

3

First International Sclerochronology Conference

Reality and Illusion in Interpretation of Daily Growth Increments in
Cephalopod Statoliths and Fish Otoliths
Alexander I. Arkhipkin, and Zhanna N. Shcherbich
Fisheries Department, Falkland Islands Government, Stanley, Falkland Islands

Cephalopod statoliths and fish otoliths are calcareous structures located in the equilibriumorgans, which serve to detect body accelerations during movement in water. Various informationis recorded in the statolith and otolith microstructure, making them popular tools in studies of thebiology and ecology of cephalopods and fish especially over the last two decades. Unlike fish
scales and squid gladii, the statoliths and otoliths grow in three-dimensional space, changing
their shape from a simple droplet or grain in larvae to the differentiated adult shape comprisingvarious distinct parts. To analyze their microstructure, the statoliths and otoliths need to be
ground to obtain a thin two-dimensional section. Usually, both sides are ground, until the starting
point of the growth (focus) and the edge are fully exposed to be examined at x400-1000
magnification under transmitted light of a compound microscope. It is extremely important tochoose both an appropriate plane of grinding and thickness of the section to reveal growthincrements. Various parts of the statolith and otolith are ground in different species, depending
where the widest and clearest growth increments are located. The growth increments are best
resolved when they are cut perpendicular to the focal plane of the microscope, which is notalways possible because the statolith and otolith parts often change the direction of their growthduring ontogenesis. Stronger deviation from the right angle between the focal plane and growthincrement lines makes their resolution weaker. Moreover, the diffraction of transmitted lightfrom the increment parts which are not in focus may create optical effects such as alternatingtransparent and oblique lines. They are usually narrower and weaker than the real growthincrements. These lines may be interpreted as either sub-daily or even daily growth rings,
causing a significant over-estimation of the animal’s age. Several different techniques ofgrinding including sectioning at different grinding planes, and usage of various optical tools of
the microscope are suggested to enhance the readability of growth increments.
Contact Information: Alexander I. Arkhipkin, Fisheries Department, Falkland Islands Government, FIPASS,
Stanley, FIQQ 1ZZ, Falkland Islands, Phone:+500-27260, Fax:+500-27265, Email: aarkhipkin@fisheries.gov.fk

4July 17-21, 2007 z St. Petersburg, Florida USA

Population Genetics of Mercenaria in Florida: Patterns and the Influence of
Scientific and Aquaculture Activities
William S. Arnold
Florida FWCC Fish and Wildlife Research Institute, St. Petersburg, Florida USA

Hard clams of the genus Mercenaria support important commercial fisheries throughout the
Atlantic and Gulf of Mexico coasts of the United States. However, the abundance of hard clam
populations suitable for commercial exploitation has declined in recent decades, creating an
opportunity vacuum that has been filled by the aquaculture industry. Two species of Mercenaria
occur in U.S. waters, but only the northern hard clam Mercenaria mercenaria is suitable forcommercial exploitation due to shelf life issues. That species is common along the Atlantic coastof the U.S. including Florida, but historically did not occur along the Gulf of Mexico coast ofthat state which instead is characterized by the congener M. campechiensis. Initially in an effort
to develop hard clam aquaculture along the Gulf of Mexico coast of Florida, and then to support
that industry, large numbers of M. mercenaria have been introduced into the Gulf at various sites
and times. The purpose of the present study was to investigate the impact of those introductions
upon the genetic composition of the resident M. campechiensis population.
Application of sclerochronological techniques formed the basis of this study. Beginning in 2001
and continuing through 2003, hard clams were collected from the resident population at sites
ranging from Wassaw Sound, Georgia to Pensacola Bay, Florida. At some of those sites (e.g.,
Cedar Key) hard clam aquaculture activities had been underway for several years, whereas atother sites there was no history of clam aquaculture activities although other M. mercenaria
introductions had occurred at a subset of the latter sites. To assess the impact of these
introductions on the genetic character of the hard clam population at each site, soft tissue
samples were collected from each individual at each site and analyzed according to establishedgenetic techniques. Results allowed for an assignment of each individual to one of threegenotype classes: M. mercenaria, M. campechiensis, or a hybrid of the two species.
Concomitantly, one valve from each specimen was sectioned and its date of birth determined byback calculating using the age and date of collection of the specimen. Date-specific genotype
composition was then compared against the history of scientific and commercial aquaculture
activities at each site.
Results indicate that, at least at Cedar Key where a substantial aquaculture industry developed in
1994 and continues to the present, the introduction of M. mercenaria has had a substantial
impact on the genetic structure of the resident wild clam population. At other sites, whereaquaculture is not underway but where M. mercenaria had been introduced in support ofscientific investigations, results were more equivocal but also indicated that the genome had beenaltered by these introductions. Ultimately, these introductions may eliminate pure-species M.
campechiensis from many of the west coast habitats that it has historically occupied.
Contact Information: William S. Arnold, Florida FWCC Fish and Wildlife Research Institute, 100 Eighth Avenue
SE, St. Petersburg, Florida 33712 USA, Phone 727-896-8626, Fax 727-893-1372, Email: bill.arnold@myfwc.com

5First International Sclerochronology Conference

An Innovative Laser Analytical Method for Data Records from Mussel ShellsPeter Bisling
Institute for Coastal Research, GKSS Research Center, Geesthacht, Germany

The chemical analysis of annual or seasonal growth increments of hard biological structures suchas mussel shells may help monitoring and reconstructing the history of the varying
environmental conditions in which they lived. The detection of trace elements from the marine
environment incorporated into the narrow skeletal growth lines requires special micro analyticalsample preparation techniques. In the traditional way this can degenerate into hard work. In any
case micro samples make high demands on the detection limit, thus only mass spectrometricmethods can provide the sensivity necessary to detect trace elements. Up to now, Laser Ablation
Inductively Coupled Plasma Mass Spectrometry (LA–ICP–MS) has been used for studying a
range of elements in records of growth increments. Such instruments provide high spatial
resolution and minimal sample preparatory work due to the intrinsic properties of laser ablation.
Another analytical technique for the detection of elemental distributions over various lengthscales is Secondary Ion Mass Spectrometry (SIMS), which uses primary ions to eject target
material from the sample surface and mass analyzes the secondary ions of the target. Since mostof the sputtered particles are neutral, sometimes the secondary neutral particles are post–ionized
for mass detection. The detection limits of LA–ICP–MS and SIMS are often limited by matrix
effects and signals from molecular adduct ions which interfere with target substances. A new
way to combine a direct and fast spatially resolving micro sampling with a sensitive andselective detector is based on the advantages of laser ablation and post–ionization using a novel
method to integrate laser techniques and mass detection in a single instrument.
The analysis takes place in a vacuum recipient with three stages. A hard tissue sample on athree–axis micro positioner in the sample chamber is first vaporized by laser ablation to form aplume of neutral gas–phase particles. A supersonic jet of helium carrier gas transports thissample plume to an ionization source. Here, radiation from tunable laser sources excites
resonantly and ionizes selectively the target atoms or molecules in the sample plume. Finally, theresultant ions are mass dispersed and detected in a time–of–flight mass spectrometer. No
significant matrix effects are expected when separate lasers for ablation and post–ionization areused. Under optimized conditions the ablation process provides a representative composition of
the sample. Improved sensivity is a result of the enhancement in cross sections upon resonant
excitation. Thus, only small amounts of analyte are required, and unlike nonresonant methods,
molecular or isobaric interferences are effectively eliminated. Since the electronic structure ofeach species is unique, resonance ionization schemes with specific laser wavelengths can befound for almost every element of the periodic table, many molecules and molecular fragments.
First results on mass spectra recorded from shells of ensis directus and mytilus edulis, e.g. insearch of vanadium as a tracer for crude oil, will be a topic of this contribution.
Contact Information: Peter Bisling, GKSS Research Center, Institute for Coastal Research, Department KSC,
Postfach 11 60, D–21494 Geesthacht, Germany, Phone: +49 4152 87 1838, Fax: +49 4152 87 1888,
Email: bisling@gkss.de

6July 17-21, 2007 z St. Petersburg, Florida USA

Application of Tree-Ring Techniques across Diverse Taxa and Ecosystems in
the Pacific Northwest, USA
Bryan A. Black and George W. Boehlert
Hatfield Marine Science Center, Oregon State University, Newport, OR, USA

We explore potential applications of dendrochronology techniques to Pacific rockfish andfreshwater and marine bivalve species collected throughout the Pacific Northwest, USA. First,
we show that in all species the dating control procedure of crossdating can be applied to ensurethat all growth increments are assigned the correct calendar year. Crossdated age estimates canthen be used to generate accurate estimates of population age structure and recruitment history.
In a comparison of crossdated and ring count data, crossdated Pacific geoduck (Panopea
abrupta) recruitment appears to be much more episodic than ring count data would suggest.
Next, crossdated data can be used to develop growth chronologies, which establish the historical
range of variability as well as the effects of climate on growth, including the seasons of the year
in which the sensitivity to climate variability is greatest. For example, a chronology developed
for yelloweye rockfish (Sebastes ruberrimus) off northern California strongly and positively
correlates with indicators of cool, productive ocean conditions, especially during the winter andearly spring months. Finally, chronologies may be compared among one another as well as withtree-ring chronologies to explore linkages among growth in marine, freshwater, and terrestrial
ecosystems. A splitnose rockfish (Sebastes diploproa) chronology significantly (p < 0.001) andnegatively correlates with high elevation tree ring chronologies, revealing climate-driven
linkages between organisms at 300 m depth in the Pacific Ocean with those at 2,000 m in the
Cascade Mountains. Overall, we believe methods from dendrochronology could be applied toaddress a number of ecological phenomena in sclerochronology data sets.
Contact Information: Bryan Black, Hatfield Marine Science Center, 2030 SE Marine Science Dr., Newport, OR
97365, Phone: 541-867-0283, Email: bryan.black@oregonstate.edu

7First International Sclerochronology Conference

Paleoenvironmental and Sclerochronologic Reconstruction of Large OysterBearing Pliocene Reefs from Curaçao
Amanda Booth1, Michael Savarese1, Roger W. Portell2, Douglas S. Jones2 and Irvy R. Quitmyer2
1
2

Florida Gulf Coast University, Fort Myers, Florida, USA
Florida Museum of Natural History, University of Florida, Gainesville, Florida, USA

The American oyster, Crassostrea virginica, is a keystone species within estuaries along the
Gulf of Mexico. The most productive reefs are found in areas with salinities less than 15 psu orin intertidal conditions, where predation and disease intensity are minimized and foodavailability is maximized for growth and reproduction. In contrast, immense crassostreids areoccasionally found within Cenozoic deposits throughout the Caribbean and the Gulf of Mexico.
It is unclear whether these reefs formed under environmental conditions similar to those favoredby modern Crassostrea, and if growth rate and longevity are comparable. An outcrop containing
massive shells of Crassostrea sp., located within the Pliocene Seroe Domi Formation along theshores of Caracasbaai in Curaçao, Netherland Antilles, was studied to infer paleoenvironmental
conditions and investigate the life history of these unusual molluscs. Individual oysters,
associated fauna, and lithologic samples were collected. The oysters are enormous whencompared to modern Crassostrea sp., ranging up to 29.6 cm in length. Large clusters of oysters
in life position were observed; clusters ranged up to 35 cm in height and 60 cm in width. The
environmental conditions under which these oysters thrived are being investigated by analyzing
oyster taphonomy, the composition of associated fauna, and the sclerochronology/stable isotopic
geochemistry of the oyster shells. Hermatypic corals are present immediately above and below
the oyster horizon, and ahermatypic corals are present within the oyster bed. Clionid sponges(Entobia isp.) and polychaete borings (Meandropolydora isp.) appear to be the primary agents ofbioerosion. No encrusters are present on the oyster shells. The calcitic fauna is intact; however
the aragonitic fauna is moldic. Gastropods from the Family Potamididae or the Family
Cerithiidae were found to be a common faunal component. Using a micromill, successive
samples were taken along the hinge/ligament region of an oyster for isotopic analyses. The δ18O
values ranged from -0.47 to -2.19, indicating a fully marine environment. The δ13C values varied
between -6.11 and -3.31. An inverse correlation between δ18O and δ13C was observed. The
profiles exhibit cyclicity with respect to isotopic and Sr/Ca ratios which correlates with major
shell growth increments, though with appreciable variability, suggesting annual growth patterns
and seasonal fluctuations in environmental conditions. It is unclear at present whether theoysters’ large size was due to advanced age, a rapid rate of growth, or a combination of the two;
additional research on shell geochemistry will address this question. The consilience oftaphonomic, faunal, and geochemical evidence, however, fully supports a shallow marine, mudrich environmental interpretation for these Pliocene reefs.
Contact Information: Amanda Booth, Florida Gulf Coast University, 10501 FGCU Boulevard South, Fort Myers,
Florida, 33965, USA, Phone 239-590-7265, Email: acbridge@eagle.fgcu.edu

8July 17-21, 2007 z St. Petersburg, Florida USA

Do Fossil Bivalve Shells from Seymour Island (Antarctic Peninsula) Provide
Evidence for Eocene El Niño?
Thomas Brey1, Linda C. Ivany2, Bernd Schöne3, Devin P. Buick4 and John Schue2
1

Alfred Wegener Institute for Polar and Marine Research, Section “Ecology of Marine Animals”, Bremerhaven,
Germany2
Department of Earth Sciences, Syracuse University, Syracuse NY, USA
3
Department of Applied and Analytical Paleontology and INCREMENTS Research Group, Institute of
Geosciences, University of Mainz, Mainz, Germany
4
Department of Geology, University of Cincinnati, Cincinnati, USA

Sclerochronologic records preserved in fossil bivalve shells from the La Meseta Formation,
Seymour Island, Antarctic Peninsula, have provided excellent insight into both the Eocene highsouthern-latitude climate regime and the life histories of these shallow marine organisms. Highresolution microsampling and stable isotopic analysis of shells from genera Cucullaea andEurhomalea have been used to reconstruct the long-term temperature trend throughout the
Eocene, to resolve inter- as well as intra-annual variability in temperature, and to relate annual
shell growth to the seasonal temperature signal. Isotope data demonstrate that growth bands inboth taxa are annual, and counts of growth increments indicate that both taxa are extremely longlived, with lifespans approaching or exceeding a century.
Because variation in annual growth increment widths correlates with climate conditions,
measurements from these long-lived bivalves provide the opportunity to examine decadal-scale
climate patterns. Shell growth chronologies of recent bivalves living at high southern latitudes,
such as Eurhomalea exalbida from the Beagle Channel, Tierra del Fuego, demonstratesignificant coupling of shell growth to El Niño Southern Oscillation (ENSO), suggesting thatsuch a signal, if present, should be possible to extract from the Eocene taxa.
Here, we explore whether these Eocene growth chronologies exhibit consistent decadal patterns,
and particularly whether they provide evidence for or against ENSO like decadal or multidecadal patterns in the southern Pacific during the Eocene. Increment width data are detrended
using standard techniques developed for dendrochronology. The detrended chronologies are thensubjected to singular spectrum analysis and reconstruction (SSA/R) and to Multi Taper Method
spectrum analysis ( MTM) to identify periodicity in stationary time series. All shells analyzed todate show some similar peaks, one at 8+ years and one between 4 and 5 years, suggesting that
ENSO-like patterns may have been evident during the Eocene.
Contact Information: Thomas Brey, Alfred Wegener Institute for Polar and Marine Research, Section “Ecology ofMarine Animals”, P.O. Box 120161, 27515 Bremerhaven, Germany, Phone: ++49-471-48311300,
Fax: ++49-471-48311918, Email: Thomas.Brey@awi.de9

First International Sclerochronology Conference

Age and Growth of the Patagonian Scallop Zygochlamys patagonica (Kingand Broderip, 1832) Using a New Technique on the Hinge Ligament
Paul Brickle, Michael Hattersley and Zhanna Shcherbich
Falkland Islands Government Fisheries Department, Stanley, Falkland Islands

The Patagonian scallop is distributed around the southern tip of South America from 42°S in the
Pacific to 35°S in the Atlantic Ocean, on the Burdwood Bank and the on Falkland Islands’ shelf.
It is found on sandy and muddy grounds at bottom depths of 40 to 200 m, and although is mostly
abundant along the 100 m isobath it has been found in depths as low as 10 m in the Falkland
Islands. This study employed a new method of processing hinge ligaments for ageing andcompared them to a traditional method of reading hinges and to two methods of reading shells
namely x-ray photography and direct readings. The method employed a dorso – ventral section
through the hinge ligament that was ground and polished resulting in a clear preparation that waseasier to read as it highlighted the presence of earlier growth bands. Former studies examinedligaments that were split in half and mounted, which did not reveal these bands. We concluded
that the shell and x – ray underestimated age when compared to those taken from the ligament
hinge because the initial rings of the shell surface were difficult to distinguish and the rings
adjacent to the shell margin were compressed and difficult to discern. The readings taken fromthe ligaments showed good precision with Indices of Average Percent Error (IPAE) values ofless than 3% for inter and intra reader comparisons. Our results showed that the Patagonian
scallop is relatively slow growing attaining a maximum observed age of 18 yrs. The growth ofscallops and their age structure in different beds around the Falkland Islands is discussed.
Contact Information: Paul Brickle, Falkland Islands Government Fisheries Dept., PO Box 598, Stanley, Falkland
Islands, FIQQ1ZZ, Phone: 0050027260, Fax: 0050027265, Email: pbrickle@fisheries.gov.fk

10July 17-21, 2007 z St. Petersburg, Florida USA

Growth Increment Analysis as an Archaeological Measure of Shellfish
Collection Intensity
Meghan Burchell1, Aubrey Cannon1 and Darren R. Gröcke2
1
2

Department of Anthropology, McMaster University, Hamilton, Ontario, Canada
School of Geography and Earth Sciences, McMaster University, Hamilton, Ontario, Canada

The application of growth increment analysis to archaeological research has traditionally been ameans to determine the season of shellfish collection. This method has been applied to shell
midden assemblages on the coast of British Columbia (BC), but with limited success. The mostcommonly consumed species Saxidomus gigantea (Butter Clam) shows too much variation in thecolouration of shell material to be used to determine seasonality. Furthermore, clams in the senilestages of growth cannot be used for the identification of seasonality because of irregular growthbanding. However, the analysis of growth increments, focusing on the identification of growth
types has the potential to reveal insights into prehistoric shellfish collection practices.
Identifying the presence of juvenile, mature, or senile growth in shellfish assemblages allows forthe reconstruction of relative measures of collection intensity. Sectioned bivalves obtained fromshell midden sites in two distinct regions on the BC coast are compared to investigate trends inshellfish use. The preliminary results indicate the presence of different types of collection
practices ranging from light-casual collection to intensive shellfish harvest. The Namu region on
the central coast of BC in traditional Heiltsuk territory shows consistent differences between
specialized gathering and residential sites. This pattern is consistent through the Namu sites,suggesting a harvest strategy that was maintained for more than four millennia. In comparison,sites from the Dundas Islands Group on the north coast of BC in traditional Tsimshian territory
show a more intensive gathering strategy at both village and campsites. Long-term trends inshellfish collection can be interpreted as a function of site use, a response to resource stress,
and/or the implementation of harvest strategies controlled by territorial access to the resources.
Contact Information: Meghan Burchell, Department of Anthropology, McMaster University. 1280 Main StreetWest. Hamilton, ON. L8S 4L9, Phone: 905-525-9140, Fax: 905-522-5993, Email: burcheme@mcmaster.ca

11First International Sclerochronology Conference

A 150-Year Chronology Using Growth Increments In The Shell Of Arctica
Islandica From The Irish Sea
Paul G Butler, Christopher A Richardson and James D Scourse
School of Ocean Sciences, College of Natural Sciences, University of Wales, Bangor, UK

Synchronized annual banding patterns in the shell of the mollusc Arctica islandica (Linnaeus
1767) allow growth increment chronologies to be constructed by cross-matching incremental
records from multiple specimens. A number of such chronologies have been constructed over the
past decade, some of which cross match live caught and dead collected shells to extend therecord back in time by as much as 200 years. A significant constraint on much of this researchhas been the lack of suitable instrumental records with which to calibrate the increment widths
and any geochemical proxies in the shell. Those instrumental datasets that have been used havetended to be short term (satellite data), poorly resolved (continuous plankton recorder data),
synoptic (the NAO index) or some distance removed from the site of the chronology. If theincrement widths and geochemical properties in the shell of A.islandica are to be used as robust
proxies for the marine environment of the North Atlantic shelf seas, it is essential that they beclosely analyzed in relationship to long term and local instrumental records.
We present here a cross-matched 150-year absolutely dated chronology for A.islandica from
Irish Sea waters off the south-west of the Isle of Man, UK. The strongly synchronized growth inshells from this site (expressed population signal > 0.85 for most of the period) indicates acommon environmental forcing.
A significant benefit associated with this site is the existence nearby of two long-term
instrumental stations. Records of sea surface temperature, salinity, chlorophyll, nitrates,
phosphates and silicates have been kept on a weekly or fortnightly basis at the CYPRIS station of
the Port Erin Marine Laboratory for up to 50 years. SST has also been measured at the entrance
to the harbour at Port Erin since 1904.
Of particular interest is a strong cyclic signal, with a period of approximately ten years, in therelationship between the growth increment chronology and the local salinity signal. A highly
significant positive correlation (r=0.61, p<0.01) across a thirty year window (1965-1995) is
repeated, often with equal strength, when the chronology is offset against the salinity record by 10, +9 and +19 years. A negative relationship, of similar strength and with the same phasing,exists between the chronology and the winter NAO index. This finding differs from previous
research in which a positive correlation was reported between increment widths in North Sea
A.islandica and the winter NAO index (although the phasing described in that research iscomparable). The difference between the responses of the two populations may be due tohydrographical factors. A.islandica from the Isle of Man live in shallower waters (depths of 3040m) than those from the North Sea. Their habitat is also influenced by the western Irish Sea
gyre, a cyclonic eddy system with a central core of seasonally stratified water. We suggest thatthe relationship between the NAO, salinity, and incremental shell growth is mediated through theeffect on nutrient supply to the seabed of some combination of regional precipitation patterns andcyclic shifts in the position of the gyre.
Contact Information: Paul G Butler, School of Ocean Sciences, Menai Bridge, Anglesey, LL59 5AB, United
Kingdom, Phone: 01248 382853, Email: osp03e@bangor.ac.uk

12July 17-21, 2007 z St. Petersburg, Florida USA

Coral Skeletal Records of Heavy Metal Pollution from the Mesoamerican
Reef
Jessica E. Carilli1, Nancy Grumet2, Konrad Hughen2 and Richard D. Norris1
1

Scripps Institution of Oceanography, University of California San Diego, San Diego, CA, USA
Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA, USA

2

The Mesoamerican Reef is the second-largest barrier reef system in the world, and lies offshoreof Mexico, Belize, Guatemala and Honduras. The large mountains in Guatemala, Honduras, andsouthern Belize and low-lying land in northern Belize and Mexico’s Yucatan Peninsula meansthat rain and runoff are concentrated in the southern portion of the region. Corals closest to thissource of heavy rainfall and runoff should therefore be more heavily affected by land-based
impacts than those further away.
We have collected cores from the massive coral Montastrea faveolata from four locations acrossthe Mesoamerican Reef: 40 from the Sapodilla Cayes, southern Belize, 21 from Turneffe Atoll,northern Belize, 10 from Cayos Cochinos, southern Bay Islands, Honduras, and 7 from Utila,
northern Bay Islands. Based upon proximity to runoff sources, we hypothesize that the SapodillaCayes and Cayos Cochinos corals are more heavily impacted from land-based sources than thosefrom Turneffe and Utila.
This large suite of cores has allowed us to construct a statistically robust history of coral growth
rates from each of these sites spanning the last 100-150 years. The preliminary growth rate
results from southern Belize indicate that extension rates have slowly declined over the past
century. This decline was punctuated by a severe reduction in growth rate in 1998, which was
followed by a recovery period of several years. In addition to growth rates, we are in the processof constructing a multiproxy geochemical record of environmental change. The environmental
variables include sea surface temperature, salinity, sedimentation, organic/nutrient enrichment,
and heavy metal pollution.
Annual samples of coral from a single core at each site were separated using a band saw. These
were prepared using a multi-step leaching protocol to clean surface contamination in preparation
for trace metal analysis using an inductively coupled plasma-mass spectrometer. Combined withgrowth rate records, these geochemical measurements will yield important information regarding
changes in heavy metal pollution over time. Ultimately we hope to identify coral pollution
thresholds that lead to bleaching and an overall decline in coral reef health.
Contact Information: Jessica Carilli, 9500 Gilman Dr. 0208, La Jolla, CA 92093-0208, USA,
Phone: 858-822-2355 Fax: 858-822-3310 Email: jcarilli@ucsd.edu

13First International Sclerochronology Conference

Use of Nitrogen Stable Isotopes in Shell from Mercenaria mercenaria to Trace
Wastewater Inputs from Watershed to Estuarine Ecosystems through Time
Ruth H. Carmichael1, Theresa Hattenrath2, Ricky Alexander3, Ivan Valiela4 andRobert Michener5
1

Dauphin Island Sea lab, Dauphin Island, AL, USA
Stony Brook University, Stony Brook, NY, USA
3
University of Maine Machias, ME, USA
4
Boston University Marine Program, Woods Hole, MA, USA
5
Boston University, Boston, MA, USA
2

We used δ15N values in the organic matrix of shells from Mercenaria mercenaria to trace
variation in anthropogenic nitrogen inputs to coastal ecosystems. δ15N values in shell fromtransplanted and native clams reflected % wastewater contribution to each estuary, parallel toresponses in soft tissues, but showed a 2.3-2.5‰ shift toward lighter δ15N values. Accuracy ofδ15N values in shell material was not altered by acidification. Reliable values were obtained withas little as 80mg of shell and 100ul of acid. Within 2 weeks tissues and newly deposited shellmaterial of transplanted juvenile bivalves showed δ15N values representative of N sources toeach estuary. δ15N values in annual growth bands of native adult clams traced changes in N
sources and entry to coastal ecosystems across years. Results indicated that δ15N values in shellwere a suitable recorder of changes in N sources through time, showing an offset from tissues
likely due to differences in assimilation of N into shells compared to tissues. This approach may
be applied (in living bivalves or ancient middens) to historically reconstruct time courses of N
entry to coastal systems by allowing biogeochemical and biological data to be aligned for greater
temporal accuracy.
Contact Information: Ruth H. Carmichael, Dauphin Island Sea lab, 101 Bienville Blvd., Dauphin Island, AL, 36528,
USA, Phone: 251-861-7555, Fax: 251-861-7540, Email: rcarmichael@disl.org

14

July 17-21, 2007 z St. Petersburg, Florida USA

Calcification Rate of Montastraea Coral Species Growing under Thermal
StressJuan P. Carricart-Ganivet and Laura Chanona-Espinosa
El Colegio de la Frontera Sur, Unidad Chetumal, Chetumal, Q. Roo, México

We analyzed the relationship between mean sea surface temperature (SST) and mean annual
calcification rate from 1977 to 2003 using the density-banding pattern of specimens of the main
Caribbean reef-building corals Montastraea faveolata and M. franksi, collected in two localitiesof the Mexican Caribbean. Although a tendency of SST increase in the Mexican Caribbean was
not observed, in those years where positive SST anomalies exist, both Montastraea species
presented lower calcification rates. Calcification rate decreased ~0.14 g cm -2 year -1 for each 1°C increase in SST and zero calcification was projected to occur at ~35 °C in Montastraea
species. Our analysis concludes that elevated SSTs are already resulting in thermal stress for M.
faveolata and M. franksi in the Mexican Caribbean, even without coral bleaching.
Contact Information: Juan P. Carricart-Ganivet, El Colegio de la Frontera Sur, Unidad Chetumal, Apdo. Postal 424,
Chetumal, Q. Roo 77000, México, Phone: +52 (983) 8350440, Fax: +52 (983) 8350454,
Email: jpcarri@ecosur-qroo.mx

15

First International Sclerochronology Conference

Arctic Bivalves as Proxies of Local and Large-Scale Climatic Variations:
Analysis of Pan-Arctic Growth Patterns
Michael L. Carroll1, William G. Ambrose1, 2, Michael Greenacre3, Lisa Clough4,
Kelton McMahon5, Lani Stinson2 Jessica Edgerly2 and Simon Thorrold5
1

Akvaplan-niva, Polar Environmental Centre, 9296 Tromsø, Norway
Department of Biology, Bates College, Lewiston Maine, USA
3
Pompeu Fabra University, 08005 Barcelona, Spain
4
Biology Department, East Carolina University, Greenville, NC, USA
5
Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
2

The Arctic experiences decadal-scales climatic oscillations, offering the opportunity toinvestigate effects of climate change on marine communities. We examined growth rates of thecircumpolar Greenland Cockle (Serripes groenlandicus) from Rijpfjord, a high-Arctic fjord in
Northeast Svalbard (80º 10' N), over a period of nearly 20 years and from Kotzebue Sound
Alaska (67° 10' N) over 14 years. Both periods encompassed large changes in local climate andgrowth rates. Growth of Serripes was determined using external annually-deposited growth lines.
Interannual variation in growth followed a cyclical pattern, and corresponded very closely to the
Arctic Climate Regime Index (ARCI) at both locations, with high growth rates corresponding to
the positive phase characterized by cyclonic ocean circulation and a warmer and wetter climate
in Norway, but to the negative phase with opposite conditions in Alaska. In Alaska, growth was
also related to the winter Arctic Oscillation, and the North Pacific-Aleutian Low Index. Growth
rates were influenced by local manifestations of the large scale climate oscillations, with
precipitation being most important in Norway, and air temperature, wind strength, and date offreeze-up being important predictors of growth for the shallower-dwelling Alaskan cockles.
Some relationships were stronger when the environmental parameters were lagged one year withrespect to growth. Our results suggest that climate change will likely impact Arctic benthic
communities, but that effects will be determined by changes in environmental parameters
regulating food availability and temperature on a local scale.
Contact Information: Michael L. Carroll, Akvaplan-niva, Polar Environmental Centre, 9296 Tromsø, Norway,
Phone: (47) 77-75-0381, Fax: (47) 77-775-0301, Email: mc@akvaplan.niva.no16

July 17-21, 2007 z St. Petersburg, Florida USA

Complimentary Oxygen and Hydrogen Isotopic Records of Fluvial Conditionsin the Shells of Freshwater Bivalves
Monica Carroll1 and Christopher S. Romanek212Analytical Center for Climate and Environmental Change, Northern Illinois University, DeKalb, IL, USA
Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA

Recent technical advances have facilitated the analysis of microgram-size samples of mollusk
shell for the hydrogen isotope composition of the organic matrix. Through the strong relationshipbetween δD and δ18O in global meteoric water, the δDshell value may prove useful for
paleotemperature calculations in coastal and freshwater environments. We analyzed highresolution shell records of live unionid bivalves from several streams on the Savannah River Site
in South Carolina to determine whether TC/EA IRMS could be used to attain δDshell values. Our
results suggest that the δDshell values of samples of freshwater bivalve shells from different
streams preserve the relative distribution of δD values from the water they inhabited over their
lifetime (δDshell-δDwater = -145 ‰) after correcting for the contribution of exchangeable hydrogen(~ 36%) in organic matrix. When δDshell values are compared to the δ18O values of the mineral
fraction of the shell (CaCO3 as aragonite), they plot along a line that reflects the isotopic
composition of the waters in which the bivalves lived. This relationship is potentially useful for
paleoenvironmental reconstructions because the δD value of the organic matrix may serve as anindependent proxy for the δ18O value of water in paleotemperature equations. Some data, though,suggest that the hydrogen isotope fractionation between organic matrix and water be known
before δDshell values may be used with confidence.
Contact Information: M. Carroll, Geology Department, Northern Illinois University, Davis Hall, DeKalb, IL 60115
USA, Phone: 815-753-7945, Email: carroll@niu.edu

17

First International Sclerochronology Conference

Records of River Variation in the Shells of Freshwater Bivalves
Monica Carroll1 and Christopher S. Romanek212Analytical Center for Climate and Environmental Change, Northern Illinois University, DeKalb, IL, USA
Savannah River Ecology Laboratory, University of Georgia, Aiken, SC, USA

The trace element chemistry of mollusk shells potentially contains valuable environmental
information such as temperature or aqueous heavy metal load, yet this information is sometimes
obscured by biological overprinting from factors including growth rate and metabolism. In thisstudy we explored how trace element concentrations varied between different, yet synchronously
deposited, shell layers of the freshwater bivalve Elliptio complanata. Geochemical information
stored in the shells of freshwater bivalves is especially challenging to interpret given the wide
range of aqueous chemistries known in freshwater environments.
Freshwater bivalves from several streams on the DOE’s Savannah River Site in South Carolina
were analyzed by laser ablation inductively coupled mass spectrometry (LA-ICP-MS) to develop
high resolution trace element profiles for manganese, copper, strontium and barium across theinner and outer nacreous shell layers. The results were compared to water chemistry datacollected over the depositional period of shell carbonate. The results indicate that elemental
concentrations of the inner and outer layer are functionally related, although the inner layer has
significantly higher concentrations of Mn, Sr and Ba than the outer layer. Copper concentrations
are similar among layers but they are also related to the organic content of the shell. These
results indicate that environmental signals are recognizable in geochemical profiles constructedfrom different shell layers of a freshwater mollusk, but they may be influenced differentially bybiologically mediated processes. Therefore shell layer must be taken into account wheninterpreting elemental concentrations in bivalve shells.
Contact Information: M. Carroll, Geology Department, Northern Illinois University, Davis Hall, DeKalb, IL 60115
USA, Phone: 815-753-7945, Email: carroll@niu.edu

18

July 17-21, 2007 z St. Petersburg, Florida USA

Advances in Sample Preparation for Bivalve Growth Increment Studies
Robert M. Cerrato1 and Cathy A. Laetz2
1
2

Marine Sciences Research Center, Stony Brook University, Stony Brook, NY, USA
NOAA Fisheries, Northwest Fisheries Science Center, Seattle, WA, USA

Sample preparation is the most costly step in growth increment analyses, both in terms of effort
and supplies, and it can place severe limitations on the number of specimens studied. Preparation
methods for bivalves were originally developed for high speed (3600 RPM) lapidary equipment,
and updated methods utilizing readily available low speed (600-800 RPM) saws and grinding
wheels have not been widely published. We present several efficient preparation techniquesdeveloped specifically for low speed equipment. Included is an approach to create acetate peelsfrom unembedded specimens and a grinding method using a sample holder that prepares fourthin sections simultaneously. Additionally, a technique to accurately control and measure section
thickness is described. This technique is especially suited for quantitative measurement of shelltransparency along the growth axis, and accepting accumulating evidence that shell transparency
reflects metabolic rate in bivalves, it provides an approach to reconstruct metabolic rates in fieldcollected individuals.
Contact Information: Robert M. Cerrato, Marine Sciences Research Center, Stony Brook University, Stony Brook,
NY 11794-5000 USA, Phone: 631-632-8666, Fax: 631-632-8915, Email: Robert.Cerrato@StonyBrook.edu

19

First International Sclerochronology Conference

Population Parameters from Size-Frequency Analysis Using a Constrained
Maximum Likelihood Method
Robert M. Cerrato1, Jeffrey Kassner2 and Heather V.E. Wallace1
1
2

Marine Sciences Research Center, Stony Brook University, Stony Brook, NY, USA
Division of Environmental Protection, Town of Brookhaven, Farmingville, NY, USA

Obtaining information on age structure is fundamental to population studies, allowing theestimation of recruitment, growth, and mortality rates. Determining the age of a bivalve
generally requires sacrificing the animal, sectioning the shell, grinding, and preparing acetatepeels or thin sections. These preparation steps are time consuming and can ultimately limit the
number of individuals used in a study. In contrast, length measurements are nondestructive andquickly obtained, but inferring age from size data is problematic because of the extensive overlap
in size among cohorts.
We extend a maximum likelihood method developed by Hosmer (1973) for estimating theparameters (mean sizes, variances, and proportions of each group) of a mixture of two normal
distributions to allow the analysis of any number of cohorts present in a population. The method
constrains the fit of size-frequency data with age data obtained from shell growth increment
analysis of a random subsample. In testing the method, we found that it behaves well andconverges rapidly when the subsample of aged individuals is at least 10% of the total sample.
Likelihood ratio tests comparing age structure and size were also derived by extending Hosmer’s
method even further to include multiple sites or years. Finally, because our experience withsampling devices convinced us that all age-classes are not recovered with 100% efficiency, wederived a cross product ratio test for comparing relative mortality rates between sites. This test
does not require estimating age-specific sampling efficiency, but it does assume that the
sampling efficiency is identical between sites. These techniques are applied to examine thedynamics of a hard clam (Mercenaria mercenaria) population in eastern Great South Bay, NY.
Contact Information: Robert M. Cerrato, Marine Sciences Research Center, Stony Brook University, Stony Brook,
NY 11794-5000 USA, Phone: 631-632-8666, Fax: 631-632-8915, Email: Robert.Cerrato@StonyBrook.edu

20July 17-21, 2007 z St. Petersburg, Florida USA

Reconstructing 20th Century SST Variability in the Southwest Pacific: A
Replication Study Using Multiple Coral Sr/Ca Records from New Caledonia
Kristine L. DeLong1, Terrence M. Quinn2,3 and Frederick W. Taylor2
1

College of Marine Science, University of South Florida
Institute for Geophysics, University of Texas at Austin
3
Dept of Geological Sciences, University of Texas at Austin
2

Coral-based climate reconstructions typically have not used multiple cores from a region tocapture and replicate a climate signal largely because of concerns focused on coral conservation,
analytical expense, and time constraints. Coral Sr/Ca reproducibility through the 20th century
was investigated using three intra-colony and three inter-colony coral records from the reefs
offshore of Amédée Island, New Caledonia. Different sampling resolutions were examined incoral Sr/Ca (fortnightly and monthly) and δ18O (fortnightly, monthly, and seasonally) as well as
similar-scale subsampling of the daily in situ SST record. The mean coral Sr/Ca, δ18O, and SST
values do not change as a function of sampling resolution. The coral Sr/Ca signal is highly
reproducible; the average absolute offset between coeval monthly Sr/Ca determinations between
any two coral Sr/Ca time series is 0.035 mmol/mol (~0.65 ºC), which is < twice the analyticalprecision of the coral Sr/Ca measurements. The stack average of the monthly coral Sr/Cavariations and monthly anomalies are significantly correlated with monthly in situ SST (19671992; r = -0.96, -0.64, respectively; p < 0.05, n = 302) and 1º-grid monthly SST data product(1900-1999; r = -0.95, -0.56, respectively; p < 0.05, n = 1198). The coral Sr/Ca-SST
reconstruction exhibits decadal-scale fluctuations that exceed those observed in the gridded SSTtime series, which may reflect: 1) true differences between the SST at a shallow reef site andthose averaged over a 1º-grid box or 2) inadequacies in the methodology used to create thegridded SST product when few observations are available. A warming trend of ~0.6 ºC isobserved in the 20th century coral Sr/Ca-SST record.
Contact Information: Kristine L. DeLong, College of Marine Science, University of South Florida, 140 7th Avenue
South, St. Petersburg, FL 33701 USA, Phone: 727-553-1017, Fax 727-553-1189, Email: kdelong@marine.usf.edu

21

First International Sclerochronology Conference

Shell Microstructure of Ocean Quahog, Arctica islandica: Past and Present
Elena Dunca1, Harry Mutvei1 and Edward Kulakowski2
1
2

Swedish Museum of Natural History, Stockholm, Sweden
Institute of Zoology, Russian Academi of Science, St. Petersburg, Russia

In the last decades it has been demonstrated that growth of ocean quahog (Arctica islandica)shells reflects climate changes and it is an increasing trend to use these shells as environmentalarchives. Growth increment chronologies, as well as isotope analyses, calibrated against
temperatures, are employed to reconstruct temperatures. However, shells from shallow water
environment along the costal regions are more exposed to salinity fluctuations and to pollutantsfrom human activities than shells from deeper regions. Therefore, further studies are needed toreveal the impact of water chemistry on shell growth and structure. In the present paper, we
compare the shell structure of ocean quahog collected recently from Kiel Bay, along the Swedish
West Coast to Island, Spitsbergen and White Sea with subfossil shells from museum collections
dated from Tertiary to Holocene.
The shell of ocean quahog is aragonitic, covered on the outer surface by an organic layer,
periostracum. The aragonitic part has two layers (inner and outer) separated by a pallial
myostracum that is composed mostly by irregular simple prisms (ISP) and occasionally a few
fibrous prisms (FP). Annual growth increments are separated by thin annual growth lines with
ISP structure and consist of crossed microstructures that are transitional from crossed lamellar(CL) to crossed acicular (CA). The annual growth increment also exhibits a granularhomogenous (HOM) sublayer beneath the periostracum. In order to visualise the microstructureof the shells we used different etching methods on vertical fracture planes of the shells. Mutvei’ssolution was used in order to fixate the organic sheets between the crystals and to etch very
gentle the aragonite. Concentrated sodium hypochlorite was used to dissolve the organic sheets
between the crystals without etching the aragonite. The etched fractions were compared withuntreated fractions of the same shells.
Tertiary shells of Arctica from have a highly organized CL microstructure with a very thinoutermost sublayer of HOM. Shells from the Holocene also have highly organized
microstructure but the HOM sublayer is thicker and there are transitional portions from CL to
CA. In the recent shells from Island, Spitsbergen and Skagerrak the microstructure is transitionalfrom CL to CA and with a HOM outermost sublayer similar to the Holocene shells. In contrast
shells from Kattegat, Öresund and Kiel Bay have a very poorly organized microstructure, mostly
HOM. Only the outer aragonitic layer shows sporadic CA microstructure. In the outer aragonitic
layer the thin growth lines are not well expressed missing the ISP structure. The shells from the
Chupa Inlet, White Sea, also have a predominant HOM microstructure in the aragonitic outerlayer, but the growth lines are distinct, composed of ISP. The inner aragonitic layer has atransitional microstructure from CL to CA. Our studies indicate that the HOM microstructure in
Arctica shells is induced by stress factors such as salinity changes and water pollution. The stressfactors also influence the size and thickness of the shells, as well as the elemental composition.
The use of these shells in temperature reconstruction studies may provide inaccurate results.
Contact Information: Elena Dunca, Swedish Museum of Natural History, Box 50007, 10405 Stockholm, Sweden,
Phone: +46-8-5195 4187, Fax: +46-8-5195 4184, Email: elena.dunca@nrm.se

22

July 17-21, 2007 z St. Petersburg, Florida USA

Determing the Individual Ages and Growth of Modern and Eocene-Oligocene
Tortoises (Reptilia: Testudines) Using Skeletochronology
Dana J. Ehret
Florida Museum of Natural History, University of Florida, Gainesville, Florida, USA

The use of skeletochronology has become a common method of incremental growth analysis
over the past 20 years. With the exception of sea turtles, this method has been largely overlooked
as a feasible alternative to scute annuli counts or carapace lengths in most turtle and tortoise
species. Incremental growth layers in sea turtles yield positive results and have been correlated toannual growth cycles. When studying bone thin-sections for skeletochronogy, a light, wide band
represents a season of rapid growth; and a thin, dark ban represents a season of slow growth or
stasis, comprising one year’s growth. For this study, growth layers are analyzed by taking thinsections from humeral shafts of specimens.
The discovery of an unusually rich assemblage of fossil tortoises in northwestern Nebraska
warranted study of skeletochronology in the specimens. Incremental growth rings are a viableoption in this case for individual age determination, as carapace lengths are not preserved well in
the fossil record. The two species in question, Gopherus laticuneus and Stylemys nebrascensis,
were all collected from the White River Group (~35 to 30 million years old) of the central UnitedStates. Individual bones were selected, and thin-sections were prepared to estimate the tortoises’
ages. Before thin sectioning fossil materials, a modern analog (Gopherus polyphemus) was tested
to determine the validity of methods used. This modern example shows enough similarities insize and presumed environmental conditions to provide a good comparative analog.
In addition to using skeletochronology, all modern specimens were also aged using carapace andplastron lengths as well as scute annuli counts. Information gathered from Gopherus polyphemus
shows that skeletochronology is an accurate technique for estimating age in all specimens. Whileother methods failed to be accurate in older individuals. This information was then applied to thefossil species, where skeletochronology data has yielded ages in excess of thirty years forindividual tortoises measuring over one meter long.
Contact Information: Dana J. Ehret, Florida Museum of Natural History, Dickinson Hall, Museum Road & Newell
Drive, PO Box 117800, University of Florida, Gainesville, Florida 32611-7800, USA, Phone: 352-392-1721 x251,
Email: dehret@flmnh.ufl.edu

23

First International Sclerochronology Conference

Recording Paleoenvironmental Conditions By Mollusc Shells Using
Cathodoluminescence And Stable Isotope Sclerochronology
Laurent Emmanuel1, Franck Lartaud1, Damien Huyghe1, Didier Merle2, Eric Verrecchia3 andMaurice Renard1
1

UPMC, Biominéralisations & Paléoenvironnements, Paris, France
MNHN, Paléobiodiversité & Paléoenvironnements, Paris, France
3
Université de Neuchâtel; Institut de Géologie et d’hydrogéologie, Neuchâtel, Switzerland
2

Mollusc shell growth and biogeochemistry are widely used to reconstruct recent and pastenvironmental variations. Preliminary studies previously showed that geochemical δ18O
variations along the growth axis of mollusc shell might record seasonal sea-surface temperature(SST) for different environments with a high accuracy. Shell increments contain information
related to the evolution of the environment in which the organism grew during its
biomineralisation. But how can the effects of different environmental (temperature, salinity)
fluctuations on geochemical cycles in the shells be discriminated?
To extract this information, we made a comparative isotopic study on fossil gastropod and oyster
shells coupled, (when possible), with a cathodoluminescence analysis. Thus, CL of shells can beused as a sclerochronological tool (Lartaud et al., 2006). But it is well known that the shell
growth pattern is influenced by environmental fluctuations and can be seen as a sensor ofenvironmental variations. Geochemical variations within the calcite or aragonite layers of oyster(Ostrea bellovacina – Thanetian ; Crassostrea longirostris – Rupelian) and gastropod shells(Velates perversus – Ypresian ; Turitella terrebellata – Lutetian) of the Paris Basin (France),
were examined at different resolution scales (daily to seasonal). High-resolution δ18O and δ13C
measurements provide detailed records of seasonal changes in seawater chemistry in relationshipwith climatic evolution during the Eocene. The sclerochronological study made on shells leads tothe identification of growth patterns and anomalies related to environmental parameters (such as
water temperature variations) while isotope profiles suggest variable secondary stressors(salinity, nutrients availability) or metabolic control due to highly variable environmental
conditions.
Numerous spectral analyse (such as Fourier and wavelet analysis) were performed on the signals
from CL images and geochemical analyses in order to obtain trends, variability, and cyclicity
information. After the study of each shell separately, samples were compared to one another inorder to look at the variations in the record between different mollusc species from the same anddifferent stratigraphic periods. The results were compared to physico-chemical variables, which
can be estimated from the geochemical data. The inter- and intra-specific variations inrelationship with time and space were tested to evaluate the accuracy of the different
environmental proxies.
Cathodoluminescence microstructure imaging and geochemical analysis of mollusc shells might
be potential and powerful tools for the validation of a scleroclimatological approach during the
Cenozoic climatic evolution of mid-latitude sites and could be used to reconstruct the
paleogeographic framework at a regional scale during the more recent transition fromGreenhouse (Eocene) to Icehouse (Oligocene) climate modes.
Contact Information: Laurent Emmanuel, UPMC, JE2477 Biominéralisations & Paléoenvironnements, Case postale
116, 4 place Jussieu, 75252 Paris Cedex 05, France, Phone : +33 (0)144272359, Fax : +33 (0)144273831,
Email : laurent.emmanuel@upmc.fr

24

July 17-21, 2007 z St. Petersburg, Florida USA

How to Decode Individual Fish Movements Archived by Fish Otoliths? A
Bayesian Perspective
Ronan Fablet1, Françoise Daverat2 and Hélène de Pontual1
1
2

Ifremer, Laboratoire de Sclérochronologie des Animaux Aquatiques, Plouzané, France
Cemagref, Cestas, France

Numerous studies exploiting otolith microchemistry have stressed the remarkable potential of theotolith with a view to tracing fish movements and migration patterns. The chemical compositionof fish otoliths is known to be influenced by the physicochemical properties of the ambientenvironment. Besides, new high-resolution spectrometers have provided the mean forsequentially analyzing the evolution of the chemical composition of the otolith along the fish
lifespan at a resolution consistent with a time scale relevant for fish migration analysis. One
might, for instance, cite the use of Sr:Ca otolith ratios as records of fish movements through a
gradient of salinity. The challenge has however mainly been a matter of data acquisition rather
than a matter of data interpretation and model. The analysis of otolith records generally rely on avisual interpretation which does not fully exploit their potential. This communication proposes
an unsupervised and automated scheme for the reconstruction and the categorization of fish
movements among contrasted environments from sequential otolith signatures.
Formally, this issue is stated as a Bayesian segmentation which comes to estimating unobserved
state variables within a finite state space (i.e., variables accounting for the labels associated withdifferent habitats possibly visited by the fish) from a sequence of observed variables (i.e., asequence of otolith signatures from the core to the edge). The proposed probabilistic framework
involves two main components. The observation-driven component evaluates the likelihood ofan observation, ie the signatures of the otolith at a given time, with respect to a given state label.
The second component models the temporal dynamics of the state sequences, ie the dynamics the
migration pathways. A first-order Markov chain parameterized is exploited to express the
temporal dependence of state sequences. Major interests of this well-founded formulation arethat efficient and optimal procedures permit solving for:•the unsupervised estimation of both the parameters of the state-based models and of thestate dynamics given a set of unlabelled sequences of fish otolith signatures ;•the exact estimation of the most likely state sequence associated with any sequence of
otolith signatures given the estimated model parameters.

To demonstrate the relevance of the proposed approach, two datasets are analyzed: a simulated
dataset of fish migrating between two water masses of distinct mean temperatures, and a real
dataset of eels from the Gironde watershed for which Sr/Ca otolith signatures have beenvalidated to be correlated to the eel stays in river, estuarine and marine compartments. These twodatasets provide a comprehensive and quantitative illustration of the key contributions of the
proposed framework in terms of unsupervised reconstruction, analysis and categorization ofindividual fish migration patterns from otolith signature sequences. As a conclusion, thegenericity of the proposed approach as well as its applications to other state-based biologicalarchive decoding issues are discussed.
Contact Information: R. Fablet, Ifremer/LASAA, BP 70, 29280 Plouzané, France, Phone: +33298224388,
Fax :+33298224651, Email: rfablet@ifremer.fr

25

First International Sclerochronology Conference

Otolith Morphogenesis Analysis: an Automated Computer Vision Framework
Anatole Chessel and Ronan Fablet
IFREMER/LASAA, Ifremer centre de Brest, Plouzané, France

Biological structures growing according to an accretionary process can be viewed as a
succession of layers whose composition (in terms of crystalline organization and chemicalsignatures) is driven by endogenous and exogenous factors. If manual analysis of images from apredefined observation plane, depicting internal ring-like structures, are commonly used, theautomated methods have been mainly restricted to the analysis of the external shape of thesebiological structures, due a lack of dedicated image analysis methods. The psychovisual based
multi-level set method presented here, dubbed Motolith, recovers the successive shapes of theotolith from grey-scale images as the isocontour lines of a hill-shaped function centred on the
nucleus. It provides us with the basis for studying the actual morphogenesis of fish otoliths andautomating the extraction of structural information such as internal ring structures.
The extraction of information from otolith images is a difficult computer vision problem becauseof the poor contrast, the presence of noise and the intra- and inter-specific variability. Human
vision, which is the only available model for computer vision, works by grouping isolated visualcues according to several distinct grouping (or gestalt) laws. In the otoliths case, the mostimportant one is the good continuity gestalt, which tends to build continuous and smooth curves
despite possible holes or noise cluttering them. Others include parallelism closeness orconcentricity of the curves corresponding to the successive outlines of the otoliths. The presented
algorithm accounts for those laws in two steps. First orientation field is built, in which each pointof the image is associated to the estimated tangent of the structure that would pass thought it.
Second the looked after curves are computed as the level-lines (isocontour) of a dome shaped
potential centred at the otoliths nucleus which are automatically adjusted to the orientations built,
so as to be as tangent to them as possible.
Such a hill-shaped representation stem both from psychovisual constraints (the grouping laws
described above) and biological constraints (the accretionary process that lead naturally to slowly
varying concentric structures). As underlined by D'Arcy Thompson in his seminal work, using
such a third dimension is a natural way to represent the temporal variation of a shape.
Applications to the automation of the extraction of structural information from otolith images,
such as growth axis and growth rings, are presented, as well as the application to the analysis of
the anisotropy of the 2D otolith growth with respect to fish length backcalculation issues. Future
research directions based on the proposed framework, including otolith morphogenesis
modelling and analysis and automated age estimation, are discussed.
Contact Information: R. Fablet, Ifremer/LASAA, BP 70, 29280 Plouzané, France, Phone: +33298224388,
Fax :+33298224651, Email: rfablet@ifremer.fr

26

July 17-21, 2007 z St. Petersburg, Florida USA

Mg/Ca Ratios in Marine Bivalve Shell Calcite: Evidence for a Weak
Temperature Control, Strong Species-Specific Variation and Significant
Small-Scale Compositional Heterogeneity
Pedro Freitas1,2, Leon J. Clarke1, Hilary Kennedy1 and Christopher Richardson1
1
School of Ocean Sciences, University of Wales Bangor, Menai Bridge, Anglesey, UK
2
Departamento de Geologia Marinha, INETI, Alfragide, Portugal
The geochemical composition of biogenic carbonates has proved to be one of the most valuable
sources of information on Earth’s past climates and oceanographic conditions, traditionallythrough use of their stable oxygen-isotope (δ18O) composition as a proxy for seawatertemperature. More recently, the predicted thermodynamic control of the Ca2+ substitution by
Mg2+ in inorganically precipitated calcite and the observed temperature dependence of Mg/Ca
ratios in some biogenic calcites (e.g., foraminifera, ostracodes and coccoliths), has resulted in thisproxy being seen as a salinity/δ18Oseawater independent temperature proxy that makes an ideal
companion to the δ18O geochemical proxy.
Laboratory calibration and validation work, with respect to Mg/Ca ratios as a palaeotemperature
proxy, is fairly extensive for foraminifera, but for marine bivalves such work, as well as any
assessment of secondary factors that influence the composition of marine bivalve shell calcite,
has been much less well developed. The occurrence of an unequivocal temperature control on
marine bivalve shell calcite Mg/Ca ratios has been the subject of several studies that havereturned contrasting results and thus a clear dependence of this geochemical proxy on
temperature remains uncertain.
This presentation includes a compilation of marine bivalve shell calcite Mg/Ca ratio and seawatertemperature data, obtained from the literature as well as new field and laboratory experimental
studies. Data are available for three bivalve species, the fan mussel, Pinna nobilis, the blue
mussel, Mytilus edulis, and the king scallop, Pecten maximus, and highlight several important
aspects. 1. Bivalve calcite Mg/Ca ratios are strongly species-specific. 2. A large degree of nontemperature variability in Mg/Ca ratios is observed between and within individual shells of thesame species. 3. Large small-scale heterogeneity in the Mg distribution is evident within single
shells of M. edulis and P. maximus. In the latter case, a close relationship also has been observed
between Mg/Ca ratios and the deposition of elaborate shell features and/or surface and internal
disturbance growth marks/lines, i.e. in association with disruption of “normal” shell deposition.
Such small-scale heterogeneity most likely is one factor responsible for the large variability
observed in marine bivalve calcite Mg/Ca ratios.
Recognition of the absence of any consistent relationship between seawater temperature andMg/Ca ratios in marine bivalve calcite clearly prohibits the use of this geochemical proxy atpresent for accurate and precise determination of absolute and even seasonal temperature changes
in the marine environment. Such a limitation holds true even if unique Mg/Ca ratio totemperature relationships are defined for individual marine bivalve species. A full appreciation of
the physiology and calcification mechanisms in these organisms is required in order to understandbetter the large variability of Mg contents in bivalve shell calcite.
Contact Information: Pedro S. Freitas, School of Ocean Sciences, University of Wales Bangor, Menai Bridge, LL59
5AB, U.K., Phone: 00441248382874, Email: ospe03@bangor.ac.uk -or- pedro.freitas@ineti.pt

27

First International Sclerochronology Conference

Sclerochronolgical Studies and δ18O Analyses on Modern and MSA Operculaof Turbo Sarmaticus from the Southern Coast of South Africa
Mariagrazia Galimberti and Judith C. Sealy
Department of Archaeology, University of Cape Town, Rondebosch, South Africa

The gastropod Turbo sarmaticus (Linneus 1758) is endemic to the southern coast of South
Africa. Evidence of its exploitation for human consumption have been identified inarchaeological context since the Middle Stone Age (MSA) through the Later Stone Age (LSA)
including the Holocene. As a general trend MSA specimens are bigger in size than LSA animals.
This is a starting point for this research, which will focus, in particular, on the opercula of thespecies.
This study is part of a wider project called Mossel Bay and Pinnacle Point project (MAP), whose
aim is the reconstruction of palaeovironement, palaeoecology and palaeoclimate (3P) of thesouthern coast of South Africa from about 400 000 to 30 000 years. The ultimate purpose is tounderstand if, and in that case how, changes in the 3P influenced the evolution of modern humanbehaviour.
Opercula of Turbo sarmaticus are found mainly around hearths in caves inhabited around 200
000-100 000 years ago. Sclerochronological studies, δ18O and trace element analyses have been
performed on them in order to understand whether:
1. there has been a change in the sea surface temperature (SST) and therefore ocean
temperature between MSA and modern times and in case, in which extent;
2. a change in the human pattern of seasonality, occupation or exploitation can be inferred
between MSA and LSA;
3. shell in the MSA were growing faster because they were subjected to less predation or,
instead, because there was a higher level of nutrients in the marine water which allowed
faster growth of the animals in the same amount of time.
Monthly collection of modern specimens have been carried out regularly for about 2 years inorder to create a complete modern set to compare with the archaeological signal, which consistsof about 40 specimens.
The composition of Turbo sarmaticus opercula is mainly aragonitic. Their growth is in spirals
and carbonate is deposited at the edge of the shell. The mean age of the samples collected seemto be 3-4 years. Very few studies up to now have been published on the physiology or on the
structure of Turbo opercula, therefore it was necessary to find an ideal method of processing forboth δ18O and sclerochronological studies. Eventually, for the sclerochronology, it has been
decided for staining with Mutvei solution applied directly on the polished surface of theoperculum.
The main increments seem to be fortnightly with a series of clear daily and subdaily growth lines
in between. The sclerochronological comparison between modern and archaeological specimens
is giving us a key understanding of the palaeomarine sea surface temperature of the MSA.
Contact Information: Mariagrazia Galimberti, Department of Archaeology, University of Cape Town, Private Bag,
Rondebosch, 7700 South Africa, Phone: +27 (0)21 650 2349, Fax: +27 (0)21 650 2352, Email:mgrazia@science.uct.ac.za

28

July 17-21, 2007 z St. Petersburg, Florida USA

Isotopic Records of Geoduck Shells and Environmental Changes in Hood
Canal
Yongwen Gao1,2, Todd A. Palzer3, Bob Sizemore4 and Tina Blewett4
1

Makah Fisheries Management, Neah Bay, WA, USA
School of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, China
3
Department of Natural Resources, Olympia, WA, USA
4
Department of Fish and Wildlife, Olympia, WA, USA
2

Geoduck clams (Panopea abrupta) are an economically important species in Puget Sound,
Washington, with a long lifespan up to 160 years. Although previous reports on shell ageing andgrowth patterns have been documented, this may be the first study to use geochemical means in
geoduck research. At the initial phase of our project, we selected 40 known-age geoduck shells
from three sites (Vinland, Hamma-Hamma, and Tahuya) in Hood Canal, and analyzed the annual
growth rings for stable isotope ratios (18O/16O or δ18O, and 13C/12C or δ13C). Preliminary results
showed that δ18O values of these shells ranged from -1.3 to +1.0‰ VPDB, while their δ13C
values ranged from -2.2 to +0.4‰ VPDB. Among the three sampling sites, the δ18O variation
trend of Vinland geoduck appeared similar to that of Tahuya, with historical low δ18O values in1985 and 1997, respectively. In contrast, the δ13C trend of Hamma-Hamma samples was similar
to that of Tahuya, exhibiting a stable decrease in δ13C values from 1983 to 2005. Overall, δ18O
records over the past two decades were consistent with the annual water temperature profile fromthe Department of Ecology of Washington, indicating that stable isotope signatures of geoduck
shells can be used as a powerful new tool in marine environmental studies and helpful indeducing the low dissolved oxygen event in Hood Canal. Carbon isotopes showed possible
trophic level shifts between the juvenile and adult stage in geoduck’s life history, but not as large
as finfish in the same area.
Contact Information: Yongwen Gao, Makah Fisheries Management, PO Box 115, Neah Bay, WA 98357, USA,
Phone: 360-645-3164, Fax: 360-645-2323, Email: gaoy@olypen.com

29

First International Sclerochronology ConferenceHigh Latitude Climate Variability and Its Effect on Fishery Resources As
Revealed by Fossil Otoliths
Audrey J. Geffen1, Hans Hoie1,5, Arild Folkvord1, Anne Karin Hufthammer2, Carin Andersson3,
Ulysses Ninemann3,4, Rolf Birger Pedersen4, Kjell Nedreaas5 and Johan Modin61

Department of Biology, University of Bergen, Bergen, Norway
Bergen Museum, University of Bergen, Bergen, Norway
3
Bjerkenes Center for Climate Research, Bergen, Norway
4
Department of Geological Sciences, University of Bergen, Bergen, Norway
5
Institute for Marine Research, Bergen, Norway
6
Fiskeriverket, Sweden
2

We analyzed cod (Gadus morhua) otoliths from archaeological sites in Norway to reconstruct
the temperature regime experienced by fish and determine the age structure, growth,
productivity, and stock identity of the populations represented. The Natural History Collections
at the University of Bergen hold an extensive collection of fish otoliths from prehistoric andearly historic sites from different areas along the Norwegian coast. Six cod otoliths were selectedfrom pre-medieval sites (7000-1000 years ago) and 45 otoliths from medieval sites (1000-500
years ago). These fossil otoliths were compared with otoliths collected during routine fishassessment surveys. The samples provide a clear historical time line in order to evaluate
historical changes over the past 7000 years and the geographic coverage matches the present day
stocks of North-East Arctic cod, Coastal cod, and North Sea cod.
Elemental, isotopic, and microstructure analyses were combined on individual otoliths, and theresults used to estimate: 1) the temperature regime experienced by the fish (average yearly andseasonal range), 2) season of harvest, 3) growth of the fish, and 4) the geographic source of the
fish. Specifically, seasonal temperature cycles were reconstructed from stable isotope (delta18O)
measurements along transects representing 1.5 to 3 years of life. Reconstructions of the size, age
and growth characteristics of individual fish and the population were based on otolith growthincrements. The seasonal time of capture for each cod was estimated from the opticalcharacteristics of the otolith margin as well as some stable isotope measurements. The
geographical source and stock identity of the individuals were estimated based on the measured
elemental composition of the otolith and analysis of the otolith shape.
Our multidisciplinary approach combined expertise in climate research, fisheries biology,
geochemistry, palaeozoology, anthropology and archaeology to study historical climate change
in high latitude areas and its effect on humans and their fish resources. These fish otolith samples
are a significant resource and our multi-signal analyses integrated the results of the individual
methods to provide a holistic view of the temperature regime, the fish populations, and thehuman harvesting patterns over a wide regional area over the past 7000 years.
Contact Information: A.J. Geffen, Department of Biology, University of Bergen, PO Box 7800, 5020 Bergen,
Norway, Phone: +47 5558 4435; Fax: +47 5558 4450, Email: Audrey.Geffen@bio.uib.no30

July 17-21, 2007 z St. Petersburg, Florida USA

Oxygen Isotope Variation in Relation to Opaque and Translucent Bands in
European Hake (Merluccius Merluccius) Otoliths; Comparison between High
Resolution Mass Spectrometry and Ion Probe (SIMS) Techniques
Audrey J. Geffen1, Hans Hoie1, Beatriz Morales-Nin2, José Manuel Hidalgo2 andJavier Tomas1,2
1
2

Department of Biology, Univeristy of Bergen, Norway
Instituto Mediterráneo Estudios Avanzados (CSIC/UIB), Islas Baleares, Spain

SIMS analyses of oxygen isotopes (delta18O) in European hake (Merluccius merluccius) otoliths
were performed to assess the seasonal periodicity of opaque and translucent bands formation.
Results showed a greater than expected heterogeneity in oxygen isotope composition at
microscale (20 micron spots). Hake otoliths exhibited delta18O variations in the range of 6‰
within a single fish, and as much as 2‰ between closely spaced spots. This heterogeneity isprobably explained by the levels of precision of the SIMS instrument. Nonetheless, repeatedmeasurements provided highly accurate results on standards indicating that average values areaccurate measurements of delta18O in the otolith. The reconstruction of the temperature history
of individuals indicated that hake experience large variations of temperature over short periodsof time. These variations can only be explained if hake carry out vertical migrations above thethermocline. Results also showed that most translucent bands are marked with lower delta18O
values compared to opaque bands. The interpretation of opaque and translucent bands in theotoliths is discussed in the light of these results.
The microscale pattern revealed by the SIMS analyses were compared to high resolution
micromill samples analysed with mass spectrometry. Variations in delta18O were observed inmost fish sampled from around the Balearic Islands, but the pattern was not always coincident
with otolith opacity. The range of isotope values measured by the two techniques wascomparable. The fine-scale resolution of the ion probe is still offset by the greater stability andprecision of the micromill and mass spectrometry approach.
Contact Information: A.J. Geffen, Department of Biology, University of Bergen, PO Box 7800, 5020 Bergen,
Norway, Phone: +47 5558 4435; Fax: +47 5558 4450, Email: Audrey.Geffen@bio.uib.no31

First International Sclerochronology Conference

Using Dendrochronology Techniques for Age Determination and Validationof Ring Counts for Northern B.C. Geoduck Clams (Panopea abrupta)
Darlene Gillespie, Shayne E. MacLellan and Judy McArthur
Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo, B.C. Canada

Growth increments on shells have been used to age geoducks (Panopea abrupta) in the coastal
waters of B.C. for three decades. The growth increments are assumed to be formed annually, but
this assumption has not been confirmed. The size of these increments is however, closely related
to environmental variability, especially annual variability in mean sea surface temperature,
allowing the development of corroborated growth chronologies for geoduck populations using
dendrochronology techniques. We used a master chronology for a northern geoduck populationand explored the applicability of using cross-dating to age other north coast BC geoduck
populations and to validate our existing geoduck age data. A comparison of cross-dated age
assessments and those based on historical ring counts indicate that previously assigned geoduck
ages in some of these populations may be underestimated by as much as 23 years. We looked atsamples ranging as far away as 200 km. from the original chronology site. Growth chronologies
in geoduck populations in close proximity to the master population showed very highcorrelations, displaying identical signature years between samples. Based on metrics of quality(accuracy) and quantity (efficiencies), our data suggest that cross-dating offers a promisingalternative as a production ageing technique for geoduck stock assessments.
Contact Information: Darlene Gillespie, Fish Ageing Lab, Pacific Biological Station, Fisheries and Oceans Canada,
Nanaimo, B.C., Canada V9T-6N7, Phone: 250-756-7121, Fax: 250-756-7053, Email: gillespied@pac.dfo-mpo.gc.ca

32

July 17-21, 2007 z St. Petersburg, Florida USA

Periodic Endolithic Algal Blooms in Montastrea faveolata Corals
Jessie M. Godfrey, Jessica E. Carilli and Richard D. Norris
Scripps Institution of Oceanography, University of California San Diego, San Diego, CA, USA

Cores taken from Montastrea faveolata coral heads in Belize and Honduras show strong green
banding, sometimes occurring annually, but more often at less frequent intervals. These green
bands are the remnant pigments of blooms of Ostreobium spp, a filamentous endolithic algae.
During periods of elevated temperature and/or light intensity, corals may expel theirzooxanthellae—symbiotic algae living in the coral tissue. As these algae are what provide corals
their pigmentation, we call the event “bleaching”. Bleaching allows more sunlight to penetrate
into the coral skeleton, increasing photosynthesizing activity in the coral’s endolithic algae. This
study investigates whether or not the green bands that appear in Montastrea faveolata coralskeletons are endolithic algal residue from these periods of bleaching.
The green bands of 24 M. faveolata coral cores, collected from the Sapodilla Cayes in southern
Belize, were dated and compared to look for a correlation between bands in different heads year
to year. We will also compare green band data to temperature records, cloud cover data and ageochemical proxy record for nutrients from one of the cores as these variables are known toaffect algal growth.
Contact Information: Jessie Godfrey, 9511 La Jolla Shores Dr., La Jolla, CA 92037, USA, Phone: 510-282-9539,
Email: jgodfrey@ucsd.edu

33

First International Sclerochronology Conference

Seasonal Variations Preserved in an Extinct Neogene Scallop, Chesapecten,
from Florida to Delaware, USA
Ann Goewert and Donna Surge
Department of Geological Sciences, University of North Carolina, Chapel Hill, NC, USA

Climate models estimate a 2.7°C increase in average global temperature by the end of the 21st
century. High-resolution records of climate variability on deep-time scales are needed to advanceour understanding of the impact of a warming climate on seasonality and ecological change
along a latitudinal gradient. Accretionary hard parts of organisms serve as physical (growth lines
and increments) and chemical (87Sr/86Sr, δ18O and δ13C) archives of life history, ecology, andenvironmental conditions during the life of the animal. Our goal was to examine variations inseasonality across latitudinal (~27° to 37°) and biogeographic (tropical to cold-temperate)
gradients of the Middle Atlantic Coastal Plain (MACP) during two intervals of warming: theMiddle Miocene Climate Optimum (MMCO: 17-15 Ma) and the Middle Pliocene Warm Interval(MPWI: 3.2-2.8 Ma).
We analyzed variations in annual shell growth and isotope ratios (87Sr/86Sr, δ18O and δ13C) of
twelve Chesapecten shells from the extremes of their biogeographic range (Florida andDelaware) during the MMCO and MPWI. Chesapecten is an extinct genus of scallop commonly
preserved in MAPC deposits. They inhabited subtidal marine environments during the Miocene
and Pliocene. We used 87Sr/86Sr ratios to tightly refine the timing and modeled age of the
MMCO and MPWI. Modeled ages from the MMCO and MPWI across Chesapecten’s
biogeographic extremes include: Florida (MMCO) 15.5 to 14.1±0.6 Ma; Delaware (MMCO)
18.0 to 17.5±0.4 Ma; Florida (MPWI) 3.75 to 2.05±0.9 Ma; and Delaware (MPWI) 2.45 to
1.65±0.4 Ma. We estimated seasonal temperature variability from the δ18O time series assuminginterglacial values of -0.35‰. Temperatures during the MMCO from Delaware shells (coldtemperate biogeographic province) ranged from 16.7 to 26.6°C, and temperature from Florida
shells ranged from 18.4 to 30.0°C. These data reflect a lack of seasonality from Florida to
Delaware during the MMCO. MPWI shells from Delaware (cold-temperate biogeographic
province) displayed seasonal temperatures similar to today. Like the MMCO temperature
estimates, temperature recorded in MPWI shells from Florida lacked seasonal variability, as
expected from low latitudes, but temperatures ranged from 10.2 to 15.5°C. These estimatesassumed interglacial δ18OWATER of -0.35‰. If, however, we assumed δ18OWATER of 0.65‰(modern δ18OWATER from low latitudes is higher than global seawater values because ofevaporation, then temperatures ranged from 14.2 to 20.0°C, which more reasonably compares totemperature estimates from mid to high latitudes during the MPWI. Future work will examine
whether global warming: (1) shifts the boundaries between biogeographic provinces northward;
and (2) shifts the transition of summer versus winter growth cessation in marine bivalves
northward.
Contact Information: Ann Goewert, Department of Geological Sciences, University of North Carolina, Campus Box
3315, 107 Mitchell Hall, Chapel Hill, NC, 27599-3315 USA, Phone: (919)259-6949, Fax: (919)966-4519,
Email: annieg@unc.edu

34

July 17-21, 2007 z St. Petersburg, Florida USA

Sclerochronological and Geochemical Constraints on the Timing of BiologicalInvasionsDavid H. Goodwin
Department of Geosciences, Denison University, Granville, OH, USA

Clams are biological chart recorders: their shells contain a record of environmental conditions
experienced during growth in the form of periodic growth increments and geochemical variation.
In most species, this archive begins with the deposition of the dissoconch after metamorphosis
and ultimately ends with the death of the individual. In fossil specimens, the exact date of the
beginning or end of the archive cannot be determined. Therefore, sclerochronologic andgeochemical records from fossils represent short intervals of time that cannot be directly tied toabsolute time or floating chronologies. In contrast, the date of the end of the archive from livecollected specimens can be precisely resolved—in many cases to the day or even hour ofcollection. Using this date as a pinning point, one can establish the timing of events throughout
the remainder of the chronology relatively precisely.
Here, I use this approach to constrain the timing of biological invasion events. The basic idea issimple. The timing of an invasion event can be resolved if the date of the initiation of shell
deposition is established from the first specimens to appear in a new area. To absolutely establish
the timing of an invasion, one must assume that specimens represent the initial cohort ofinvaders. If this assumption cannot be met, then this method provides minimum estimates for thetiming of invasion events. This technique is best suited for regions where species composition isclosely monitored and the likelihood of collecting the initial cohort is high.
To demonstrate this technique, I examined specimens thought to represent the initial cohort ofthe oyster Crassostrea gigas to establish a breeding population in South San Francisco Bay. All
individuals were collected live in July or August of 2006. Sclerchronological examinationsuggested that the specimens were at least three years old. These age estimates were confirmed
using stable oxygen isotope (δ18O) and stable carbon isotope (δ13C) variation. For eachspecimen, δ18O and δ13C profiles representing the complete ontogenetic history were obtained bysampling the resilifer in the left valve. In all specimens, δ18O and δ13C values were positively
correlated and show strong seasonal variation. Comparison of predicted and observed δ18O
variation suggests that both temperature and the δ18O of the water in which they grew strongly
influence the pattern of δ18O observed in the shell. Together, sclerochronological andgeochemical analysis indicate that the invasion of C gigas in South San Francisco Bay occurredat the same time.
The ability to establish the timing of a biological invasion may help scientists better understandthe dynamics of invasion events. Furthermore, these data may facilitate development of effective
regulations designed to minimize the likelihood of invasions in the future. This is particularly
important given recent failures of existing invasion prevention guidelines (e.g., the appearance ofthe quagga mussel [D. bugensis] in the Colorado River system).
Contact Information: David H. Goodwin, Department of Geosciences, Denison University, 100 Sunset Hill Drive,
Granville OH 43023 USA, Phone: 740-587-5621, Fax: 740-587-6774, Email: goodwind@denison.edu

35

First International Sclerochronology Conference

Reconstructing Intra-Annual Growth in Bivalve Mollusks: A Mathematical
ApproachDavid Goodwin and Christine Wissink
Department of Geosciences, Denison University, Granville, OH, USA

Bivalve mollusk shells contain archives of important biological and environmental data. For
example, widths of periodic growth increments record growth rates, and stable oxygen-isotope(δ18O) values vary, in part, as a function of temperature. Reconstruction of temperaturedependent intra-annual growth rates can be accomplished by counting and measuring tidal
growth increments. Unfortunately, these increments are seldom preserved in fossil specimens,
making this approach difficult in fossil specimens. Here, we present a new analytical method that
relates linear growth and time to reconstruct intra-annual growth rates, an important biologicalvariable.
The concept is straightforward; the derivative of a function relating linear growth (cumulative
distance) to time represents relative intra-annual growth rates—the growth function. To evaluate
this idea, we simulated clam growth with different hypothetical growth functions. We used anannual temperature model based on temperature variation in the Gulf of California. Each day
within the year was assigned an increment width and a δ18O value. These shells were then“sampled” assuming a 300-μm drill bit. Next, the δ18O value of each sample was converted to atemperature and assigned a date based on the temperature model. A line was then fitted to theplot of cumulative distance versus date. Finally, we graphed the derivative of the best-fit model
to reconstruct the hypothetical growth function. In all cases, we accurately reconstructed the
hypothetical growth function.
To further evaluate this approach, we reconstructed the intra-annual growth function of real
clams (Chione cortezi) with known intra-annual growth functions. Our modeled functions
reconstructed significant intra-annual growth rate variation. However, these functions did notalways match the observed patterns of intra-annual growth. We believe this disagreement stems
primarily from error assigning calendar dates to δ18O samples associated with high-frequency
environmental variation. Our ongoing research suggests that statistical re-sampling techniques
may resolve this discrepancy. This model may provide a new tool for reconstructing animportant paleobiological variable and understanding ancient environmental and/or evolutionary
patterns.
Contact Information: David H. Goodwin, Department of Geosciences, Denison University, Granville, OH 43023
USA, Phone: 740-587-5621, Fax: 740-587-6774, Email: goodwind@denison.edu

36July 17-21, 2007 z St. Petersburg, Florida USA

Growth Rate Patterns in Trachycardium procerum (Mollusca) Shells from
Coastal Peru and Relationships with ENSO-Related Environmental
Parameters
Marc Gosselin1, Ernesto Fernandez2, Luc Ortlieb1, Frederico Velasco2 and Claire E. Lazareth1
1
2

PALEOTROPIQUE, Institut de Recherche pour le Développement, Bondy, France.
Instituto del Mar del Perú, Lima, Peru.

El Nino Southern Oscillation (ENSO) is known to impact the tropical Pacific Ocean as well as
global and regional climate regimes. On the Peruvian coastline, where this phenomenon was firstdescribed, its effects are particularly significant on marine resources, including near-shore
bivalve species. Actually, strong El Niño events may decimate many species of molluscs in Peru,
and only a few bivalve species appear to resist the oceanographic alterations and related
ecological impacts. One of these relatively resistant species, Trachycardium procerum, which
can be preserved in uplifted coastal sediments and in archaeological deposits, called the attentionof previous workers who tried to use fossil shells as potential recorders of former ENSO
occurrences and/or of El Niño-induced impacts on the coastal environment.
T. procerum is a large subtidal filtering organism, commonly living in muddy and fine-sandshallow bays. Preliminary attempts to use it as proxies for El Niño occurrences were mainly
based upon stable isotope profiles and seemed to provide satisfactory information to estimate sea
water temperature anomalies, even if no clear seasonal variations could be detectedgeochemically in non-ENSO years within the same shells. Furthermore, unlike other bivalvetaxa, this species does not show obvious yearly microstructural features which would enable aneasy determination of the ontogenic age of the samples. These problems led us to carry out
sclerochronological studies on both modern and fossil shells with the general aim to understandthe growth modalities of this species and the dependence of these different modalities on
physico-chemical and ecological conditions. This is carried out through experimental growthstudies under monitored conditions (with periodical fluorochrome staining for the chronologicalcontrol) and microstructural analyses of a series of sub-fossil shells for which the date of death is
known. Increment thickness variations are tentatively compared with environmental parameters(particularly Sea Surface Temperatures and tidal variations) by wavelet analysis. A special
attention is paid to microstructural features in thin sections and external morphologicalanomalies of shells which may reflect impacts of El Niño anomalous conditions. Examples aretaken from modern and recent shells, and also include well-preserved fossil shells of different
ages (Holocene and Pleistocene).
This study was financed and conducted in the frame of the EU-project CENSOR (Climate
variability and El Nino Southern Oscillation: Impacts for natural resources and management,
contract 511071) and is CENSOR publication 0091.
Contact Information: M. Gosselin, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France, Phone : 00-33-1-48-02-55-70, Fax : 00-33-1-48-02-55-54, Email : Marc.Gosselin@ird.fr37

First International Sclerochronology Conference

Improvement of Image Analysis for Sclerochronological and PaleoEnvironmental Studies on Mollusc Shells and Fish Otoliths
Marc Gosselin, Claire E. Lazareth, Elise Dufour, Nury Guzman and L. Ortlieb
PALEOTROPIQUE, Institut de Recherche pour le Développement, Bondy, France

Extracting valuable paleoclimatic and paleoenvironmental information from a series ofgeochemical analyses along growth axes of mollusc shells or fish otoliths requires a goodunderstanding of shell or otolith formation. For most mollusc/fish species, the assumption of acontinuous and uninterrupted growth at a regular pace cannot be sustained. A meticulous
observation of the succession of increments for each considered species is then necessary for
determining the chronological significance of each carbonate sample. Therefore, not only acareful preparation of thin sections or setting of microscope light but also accuratesclerochronological analyses appear as a prerequisite in all studies on mollusc or fish material
aiming to reconstruct environmental conditions.
The precise measurement of growth lines patterns from microphotographs is a critical point. For
the characterization of growth rhythms and interpretation of growth modalities, it may benecessary to develop a specific software-assisted tool to produce objective measurements, as
independent as possible from the observer. In collaboration with Noesis Co., our team adapted
the Visilog ® image analysis software for sclerochronological studies. It takes in charge video
captures, process treatment (sharpening, smoothing) and geometric measurements analysis(angles, area, distance…) as well as intensity profiling. Calibration of the different available
microscope magnifications are easily done and registered from a graduated photography, making
possible a quick calibration of shell/otoliths pictures. A special “sclerochronological” module
added to the regular software allows the use of tags to spot growth lines or limits between areas
corresponding to different grey intensity values. The distance between the beginning of the
profile and each spotted tag is automatically calculated and loaded in a data table. The tags canbe placed either manually, or semi-automatically according to specified thresholds in the grey
intensity scale (e.g. limit between two consecutive growth lines). The software allows aposteriori corrections with automatic inclusion of the corresponding measurements in the rightposition within the data table. The software generates two kinds of numeric files that can beexported directly to spreadsheets like Excel. A first one gives us the grey-scale intensity data,
pixel by pixel, along the entire profile. The second data file contains the series of distances
measured between the intensity profile beginning and each tag. Furthermore, the software allows
the saving of pictures, profiles, tag diagrams and numeric files, thus making possible reiterated
work and file modifications in successive sessions. This technical solution proved to be quite
rewarding and time-saving. The sclerochronological profiles obtained may then be interpreted interms of growth modalities, while impacts of different environmental parameters on shell/otolith
growth can be extracted from the sclerochronological profiles with a high confidence level.
This study was financed and conducted in the frame of the EU-project CENSOR (Climate
variability and El Nino Southern Oscillation: Impacts for natural resources and management,
contract 511071) and is CENSOR publication 0092.
Contact Information: M. Gosselin, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France, Phone : 00-33-1-48-02-55-70, Fax : 00-33-1-48-02-55-54, Email : Marc.Gosselin@ird.fr

38

July 17-21, 2007 z St. Petersburg, Florida USA

Annual Growth Bands in the Carboniferous Brachiopod Gigantoproductus: A
High-Resolution Stable Isotope and Sclerochronology Study
Ethan L. Grossman, Huayu Wang and Thomas E. Yancey
Department of Geology and Geophysics, Texas A&M University, College Station, TX, USA

The sclerochronology of brachiopods shells has received limited attention in part because growthbands in brachiopods are less common and less regular than in mollusks, and in part because
many brachiopod taxa are extinct and provide no modern analogy. Consequently, little is known
about the conditions which lead to formation of growth bands. Likewise, little is known about
the seasonal climate conditions that influence shell growth in Paleozoic brachiopods. To examine
Carboniferous seasonality and the origin of growth bands in brachiopod shells, we performed
high-resolution oxygen and carbon isotopic analyses on six specimens of the brachiopod
Gigantoproductus from Visean and Serpukhovian sediments from the Moscow Basin. Shells
were milled at approximately 70 μm intervals parallel to growth bands, providing isotope data at
better than monthly resolution for all but the earliest shell growth. Trace element analyses were
performed at similar resolution by electron microprobe as a test for diagenesis, as wascathodoluminescence microscopy. In all, over 1000 isotopic and trace element analyses were
performed.
Shell interiors used for isotopic study exhibited excellent preservation as indicated by retentionof original microstructure, lack of cathodoluminescence, and low Fe and Mn contents. Excluding
two outliers, δ18O cycles vary in amplitude from 0.2 to 1.5‰ with a mean of 0.79 ± 0.3‰.
Assuming no change in seawater 18O composition, these values correspond to seasonaltemperature variations of 2 to 6°C for the early Carboniferous tropics.
Growth bands are well developed in all six Gigantoproductus shells and are near parallel to theshell surfaces. Six to >12 growth bands (strong and easily recognized) occur in each shell except
one (RU072), which has only three strong bands. Stable isotope analyses suggest that banding isannual in most but not all shells. Growth bands are widely spaced near the shell exterior andnarrowly spaced near the shell interior. This implies that brachiopod shell thickening slows withage. Some shells show distinct growth lines between bands which we interpret as tidal lines.
Growth bands show no consistent relationship with δ18O, suggesting that temperature extremes
do not cause growth band formation. We believe the growth banding results from spawning andspeculate that the irregular relation between δ18O and growth band occurrence reflects variationsin spawning season.
Contact Information: Ethan L. Grossman, Department of Geology and Geophysics, Texas A&M University, College
Station, TX 77843 USA, Phone: 979 845-0637, Fax: 979 845-6162, Email: e-grossman@tamu.edu

39

First International Sclerochronology Conference

Subdaily and Hourly Growth Patterns Within The Shell Of The Chilean
Gastropod Concholepas concholepas: New Perspectives For High-Resolution
Sclerochronological Studies
Nury Guzman1, Luc Ortlieb1, Jean-Pierre Cuif2, Yannicke Dauphin2 and C. E. Lazareth1
1
2

PALEOTROPIQUE, Institut de Recherche pour le Développement, Bondy, France
UMR IDES, Universite de Paris-Sud, Orsay, France

Unlike many mollusc species, shells of Concholepas concholepas [Bruguière, 1789] do not show
obvious annual morphological marks, neither at the macroscopic or the microscopic scales. The
coarsely reticulated structure of the outer shell of this species is produced by the intersection of
protuberant lamellae and radial ribs stemming from the apex. These lamellae do not seem to havea particular chronological significance, as they can be formed at rather constant intervals during
the first year of growth, and at a diminishing frequency during the successive years. Therefore,
the counting of these concentric lamellae is of little help to determine the age of the shells, andthe mechanisms responsible for their formation still remain to be understood. At a microscopic
level, thin sections of a transversal cut of a shell clearly exhibit that it is made up of two principal
components: an external layer formed by prismatic crystals of calcite whose thickness increases
from the apex toward the edge and an internal aragonitic layer organized in a crossed lamellar
structure. Under appropriate amplification and with a particular combination of transmitted andreflected light, the external layer shows growth structures with an alternating brownish andlighter coloured banding. These structures whose differences in colour seem to depend on theirorganic matter content typically measure between 20 and 150 µm in thickness. On another hand,scanning electron microscopy analyses reveal that the smallest growth structure consists of 2
µm-thick increments. Even though it has not been possible to directly “see” grouping of thesebio-mineralisation units under SEM, it could be deduced that the brownish and light-grey bands
are thus formed by a varying number of 2 µm-thick increments. Repeated staining experiments
realized with calcein on living shells provided a precise chronological framework for theunderstanding of the growth modality of this species. The calcein marks allowed us to establishthat the alternating bands correspond to day and night growth increments. The relative thicknessof the bands depends on the number of elementary biomineralisation units or, in other terms, on
the frequency of formation of these units. Within one of the conducted experiments which lasted
a month and a half, it could be demonstrated that the rhythm at which the organism formed these2 µm-thick units varied between half-an-hour to two hours. Understanding the growth modality
and the possibility to measure sub-daily increments within the shell of C. concholepas open new
perspectives for a series of studies on the relationships between environmental conditions andshell growth on this species. It thus becomes possible to work now on variations of chemicalcomposition of the calcitic increments (calibration of geochemical proxies for environmental
conditions) at a time scale of the order of a few hours.
This study was financed and conducted in the frame of the French PNEDC CONCHAS Project
and also benefited from the support of the EU-project CENSOR (Climate variability and El Nino
Southern Oscillation: Impacts for natural resources and management, contract 511071). It is
CENSOR publication 0093.
Contact Information: N. Guzmán, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France. Phone: 00 331 48 02 55 88, Fax: 00 331 48 02 55 54, Email: Nury.Guzman@ird.fr

40

July 17-21, 2007 z St. Petersburg, Florida USA

Influence of Sea Temperature Variability On Shell Microstructural Growth
Of Concholepas Concholepas (Gastropoda) In Southern Peru
Ernesto Fernández1, Nury Guzmán2, Luc Ortlieb2, Federico Velazco1, Sheyla Zevallos1 andMatthias Wolff 3
1

Instituto del Mar del Perú, Lima, Perú.
PALEOTROPIQUE, Institut de Recherche pour le Développement, Bondy, France.
3
Center for Tropical Marine Ecology (ZMT), Bremen, Germany2

Due to the drastic impacts of the quasi-periodical ENSO phenomenon on the Peruvian coastal
ecosystem and its shellfish resources, there is much interest to better understand the role oftemperature variability on the growth of mollusc species. In the framework of a larger study
which involves several molluscan species of economical interest, the present work focuses on theshell growth of Concholepas concholepas [Bruguière 1789], the so-called Southern Hemisphereabalone, as influenced by temperature and temperature variability. Since this species ranges fromthe cold waters of the southern tip of South America to the warmer waters of central Peru, C.
concholepas is expected to be particularly sensitive to sea surface temperature rise (i.e. El Niño
events or summer warming periods).
Field tagging-recapture growth experiments were carried out between April 2005 and November
2006, in a sub-tidal rocky shore area of Punta Picata (17°52’20.22” S; 71º04'22.7” W) between
10 and 20 m depth. Specimens were stained with a calcein solution and subsequently released
into their natural environment. Twelve organisms which were marked at least twice weresacrificed, and thin shell sections were prepared and studied with an optical microscope equippedwith fluorescent light. Initial measurements of peristomal length varied from 45 to 75 mm andgrowth rate of sacrificed organisms varied from 0.3 to 5.36 mm/month. The thickness of every
increment between the fluorescent growth lines was measured with a modified version of Visilog
software. The study was aimed to better understand variations of growth based on bothmeasurements of the peristomal length and on microscopic analyses of the daily increments
within the shells, as related to temperature variations, which were recorded through a continuous
temperature recording device. Results suggest no direct relationship between temperature andgrowth of C. concholepas shell, although colder SSTs are known to favour the biomineralisation
process in this species. Reproductive activity (and possibly also the concomitant rise intemperature, which occurs at the end of spring and early summer) limits shell growth. Growth
peaked in May 2005 (in the order of 2.47 to 4.79 mm/month) when SST reaches low values ofthe order of 14°C. In the summer of 2006, when SST reached 20°C, growth rates were reduced
by a factor of two or more. Calcein markings were used to validate increment periodicities andthus, describe the influence of temperature on growth at a very small time scale.
This study was financed and conducted in the frame of the EU-project CENSOR (Climate
variability and El Nino Southern Oscillation: Impacts for natural resources and management,
contract 511071) and is CENSOR publication 0094.
Contact Information: N. Guzmán, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France. Phone: 00 331 48 02 55 88, Fax: 00 331 48 02 55 54, Email: Nury.Guzman@ird.fr

41

First International Sclerochronology Conference

Ambient Temperatures, Metabolic Stress and Otolith Increment Formation in
North Sea cod (Gadus morhua L.)
Andrew J. P. Harwood1, A. D. Marca1, P. F. Dennis1, G. M. Pilling2 and R. S. Millner2
12School of Environmental Sciences, University of East Anglia, Norwich, Norfolk, EnglandCentre for Environment, Fisheries and Aquaculture Science (CEFAS) Laboratory, Lowestoft, Suffolk, England

Globally over 1 million fish otoliths are aged each year for fish stock assessments and theinvestigation of population dynamics. Otoliths in the North Sea have been used to age cod since
before the 1960’s. However, the factors influencing the onset and duration of opaque andtranslucent increment deposition that underlie these ages are still not well understood. It has beensuggested that the formation of translucent zones in North Sea cod otoliths is strongly influenced
by temperature, and may be triggered and sustained by a threshold of metabolic stress resulting
from the demands of growth, reproduction and migration. We tested this theory using otolith
microchemistry techniques. North Sea cod aged 2, 3 and 4 from 2 specific years, representing acold period (1986) and a warm period (1990), are examined. High-resolution carbonate samples
were taken from areas of individual otoliths across opaque and translucent zones. Individual
reconstructed temperature histories were produced using δ18O signatures and metabolic stateinferred from carbon δ13C signatures. The experienced temperatures and metabolism derived foreach fish were used to investigate age-related effects, while differences between the two years
were used to examine any temporal- and temperature-related influences. This work provides
further insights into the processes and mechanisms influencing otolith zone formation.
Ultimately, the relationships discussed will allow links with somatic growth to be studied and theimpacts of future environmental variation on exploited and recovering fish populations to beassessed.
Contact Information: A.J.P. Harwood, School of Environmental Sciences, University of East Anglia/UEA, Norwich,
Norfolk, UK, NR4 7TJ, Phone: +44(0)1603 591300, Fax: +44(0)1603 591327, Email: andrew.harwood@uea.ac.uk

42

July 17-21, 2007 z St. Petersburg, Florida USA

Coral Growth Records and the Relationship to Freshwater Discharge inSoutheast Florida
K. P. Helmle1, R. E. Dodge1 and P. K. Swart2
1
2

National Coral Reef Institute, Nova Southeastern University Oceanographic Center, Dania Beach, FL, USA
Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA

Corals naturally store records of their growth and the environment through the accretion ofannual skeletal density bands. Near-shore shallow-water corals in South Florida are subject to anumber of growth limiting factors including coastal influences of freshwater drainage and runoff.
Coral growth rates from Broward County Florida reveal a 30-year period of high skeletal
densities and low extension rates which matches a 30-year period of dramatically increased canaldischarge an order of magnitude greater than normal due to Everglades drainage. Comparison ofcoral extension with environmental variables reveals a positive correlation between extension
rate and salinity as represented by sea water density. The 30-year period of high density and low
extension skeleton is a common feature of the growth records of many corals in Broward County
dating back to the 1940’s. This relationship suggests that corals along Florida’s southeast coast
have been significantly influenced by freshwater drainage from the Everglades.
Contact Information: Kevin P. Helmle, National Coral Reef Institute, Nova Southeastern University Oceanographic
Center, 8000 North Ocean Drive, Dania Beach, FL 33004, USA, Phone 954-262-3656, Email: kevinh@nova.edu

43

First International Sclerochronology Conference

Examining Environmental Variation in a Norwegian High-Arctic Fjord:
Evidence from Serripes Groenlandicus (Bivalvia) Growth Rates and Carbon
Isotope Composition
Gregory A. Henkes1, William G. Ambrose Jr1,2, Beverly J. Johnson3, Kelton W. McMahon4,
Michael L. Carroll2 and Haakon Hop5
1

Department of Biology, Bates College, Lewiston, ME, USA
Akvaplan-niva, Polar Environmental Center, Tromsø, Norway
3
Department of Geology, Bates College, Lewiston, ME, USA
4
MIT-WHOI Joint Program, Woods Hole, MA, USA
5
Norwegian Polar Institute, Polar Environmental Center, Tromsø, Norway
2

The Arctic climate has changed dramatically within the last several decades, but the effects ofthese changes on Arctic marine ecosystems remain largely unknown. Observation of ecosystem
response to decadal scale climate variation may help elucidate the impact of climate change on
the structure and function of these ecosystems. Benthic communities may be valuable indetermining the impacts of climate variability on Arctic marine ecosystems as there is often aclose coupling between benthic and water column processes and because benthic communities
integrate processes over long time periods. Marine bivalves, which are long-lived, stationary, andcomprise a large proportion of benthic communities in the Arctic, are excellent proxies forenvironmental change. Bivalve shell growth has been shown to reflect changes in regional
environmental parameters such as temperature, precipitation, and large-scale climatic andmeteorological indices such as the ACRI, NAO, or AO. Additionally, inter- and intra-annual
variation in the carbon isotope signal of extracted shell organic material (SOM) may indicate
sources of primary production reaching the benthos. We analyzed growth rates and carbon
isotope composition of SOM of the circumpolar Greenland cockle, Serripes groenlandicus toevaluate decadal-scale environmental variation and to describe a possible shift in primary
production in Kongsfjord, a high-Arctic fjord on the west coast of Svalbard, Norway (ca. 80º Nlat.).
A 2-year running mean of the standardized growth index (SGI), an ontogenetically adjusted
measure for growth, was significantly correlated with mean annual water temperature, mean
winter temperature, and the annual NAO index, with the NAO index explaining 40% of the interannual variability in growth. During the past 5 years the highest SGIs occurred from 2000-2003
followed by decreasing SGI representing below average growth. Preliminary evidence from thecarbon isotopes of SOM suggests a shift to more enriched values post-2000, which coincides
with the period of maximum SGI. The shift in isotope values may be attributed to the increased
growth rate or to a change in environmental conditions. A comparison of winter and summer
carbon isotope values indicates intra-annual variability with greater seasonal disparity occurring
most recently. Our results suggest that S. groenlandicus from Kongsfjord are sensitive to local
and meso-scale climate variation, and could potentially be a proxy for understanding shifting
patterns in water column primary production reaching Arctic benthic communities.
Contact Information: Gregory A. Henkes, Bates College Department of Biology, 363 Bates College, Lewiston, ME
04240 USA, Email: GHenkes@bates.edu

44July 17-21, 2007 z St. Petersburg, Florida USA

Changing Growth Rate and Growth Pattern of the Northern Quahog,
Mercenaria mercenaria, in Narragansett Bay, RI (USA): A Tug of War
between Increasing Water Temperature and Decreasing Chlorophyll
Concentration
Kelly M. Henry and Scott W. Nixon
Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA

During the last 35 years, the waters of Narragansett Bay, Rhode Island have experienced
dramatic changes in both temperature and chlorophyll concentration. Compelling evidence now
exists that water temperatures have increased over this time period, particularly in the last
decade. While the warming has been the greatest during the winter months, approaching 1.5 oC,
average summer temperatures have also increased by about 1 oC. It is possible that the warmingof the Bay has increased the growth rate of the northern quahog as well as altered the annual
macroscopic growth pattern within the shell.
Temperature is not the only environmental parameter influencing annual growth rate and pattern.
Food quality and quantity, dissolved oxygen concentration, substrate, and current speed are also
known to affect growth. To complicate the response of northern quahogs in Narragansett Bay towarming, during the same 35 year period annual chlorophyll concentration (used as a proxy for
quahog food quantity) has declined by 55 percent. This decrease in annual concentration stems
primarily from a decrease in the winter-spring phytoplankton bloom.
Through a sclerochronological analysis, the opposing effects of increasing water temperature anddecreasing chlorophyll concentration on annual growth rate and pattern of the northern quahog
were determined. After comparing these growth rates to published growth rates within thissystem from the 1980’s, it was discovered that even in the face of increasing water temperatures,
northern quahog growth rates over the last 20 years were lower than those measured during theprevious study. In addition, the annual macroscopic growth pattern of northern quahogs in the
Bay has experienced some subtle changes over the last several decades.
Contact Information: Kelly M. Henry, Graduate School of Oceanography, University of Rhode Island, South Ferry
Road, Narragansett, RI 02882 USA, Phone: 401-874-6820, Fax: 401-874-6207, Email: khenry@gso.uri.edu

45

First International Sclerochronology Conference

The Effect of Early Meteoric Diagenesis on the Ca-Isotope System: A Case
Study from Altered Holocene/Pleistocene Bivalves (Gulf of Corinth Area,
Greece)A. Immenhauser1, Dorothee Hippler2 and D. Buhl1
12

Institute of Geology, Mineralogy and Geophysics, Ruhr-University, Bochum, Germany
Faculty of Earth and Life Sciences, Vrije Universiteit, Amsterdam, Netherlands

Bivalve shells provide excellent high-resolution archives for the reconstruction of pastenvironmental parameters. However, in order to test the geological reliability of geochemical
proxies from fossil bivalve shells, it is important to examine the sensitivity of the shellgeochemistry to early diagenetic alteration. For this purpose, selected fossil bivalve shells werecollected at Mavra Litharia and at Cape Heraion, two sites of uplifted marine terraces located in
the SE Gulf of Corinth area, Greece. Samples are dated to be of Holocene and Late Pleistocene(MIS 5e) age. Both sites are currently within the meteoric vadose zone. Uplift rates and sea-levelreconstructions even suggest prolonged subaerial exposure of these shells throughout the Late
Holocene. The shell material includes a series of quasi-pristine shells, such that show incipient
diagenetic alteration and such that have seen a pervasive diagenetic overprint. The degree ofshell preservation is tested by both optical and geochemical screening methods. Placing theseshells on a relative diagenetic alteration scale, Ca-isotope measurements are preformed in orderto quantify the effects of increasing diagenetic alteration on the Ca-isotope system.
Contact Information: Dorothee Hippler, Vrije Universiteit Amsterdam, Faculty of Earth and Life Sciences,
De Boelelaan 1085, NL-1081 HV Amsterdam, Phone: +31 20 5987365, Fax: +31 20 5989941,
Email: dorothee.hippler@falw.vu.nl

46

July 17-21, 2007 z St. Petersburg, Florida USA

The Microstructure of Bivalve Sshells– New Insights from the Ocean Quahog
Arctica islandica
Dorothee Hippler 1, E. Griesshaber2, R. Witbaard3 and A. Immenhauser4
1

Faculty of Earth and Life Sciences, Vrije Universiteit, Amsterdam, Netherlands
Earth and Environmental Sciences, Ludwig-Maximillian University, Munich, Germany
3
Royal Netherlands Institute for Sea Research, Texel, Netherlands
4
Institute of Geology, Mineralogy and Geophysics, Ruhr-University, Bochum, Germany
2

We investigated the microstructure across the architectural elements of the shells of the bivalve
species Arctica islandica with scanning electron microscopy (SEM) and electron backscattering
diffraction (EBSD). A. islandica is a long-lived species and is found on the continental shelves
on both sides of the North Atlantic making it an ideal archival carrier for temperate to boreal
regions. The aragonitic shell of A. islandica consists of an outer prismatic layer separated fromthe inner layer by a thin myostracum, which are all characterised by different microtexturalelements. The growth lines are composed of irregular simple prisms and the increments consistof irregular complex cross lamellar and crossed acicular-crossed lamellar microstructures.
Selected samples from 1) laboratory growth experiments, cultured at constant temperature anddietary and from 2) field experiments conducted in the Dutch Wadden Sea accompanied byinstrumental monitoring (e.g. temperature and salinity), we seek to assess the potential effect of
optimum and stress temperatures on Arctica’s shell microstructure.
Contact Information: D. Hippler, Vrije Universiteit Amsterdam, Faculty of Earth and Life Sciences, De Boelelaan
1085, NL-1081 HV Amsterdam, Phone: +31 20 5987365, Fax: +31 20 5989941,
Email: dorothee.hippler@falw.vu.nl

47

First International Sclerochronology Conference

Temperature and Salinity Relationships from Bivalve Shell Carbonate Using
Calcium and Stable Isotope Ratio Profiles
Dorothee Hippler 1, R. Witbaard2, D. Buhl3, D. Richter3 and A. Immenhauser3
1

Faculty of Earth and Life Sciences, Vrije Universiteit, Amsterdam, Netherlands
Royal Netherlands Institute for Sea Research (NIOZ), Texel, Netherlands
3
Institute of Geology, Mineralogy and Geophysics, Ruhr-University, Bochum, Germany
2

We conduct field experiments in the Dutch Wadden Sea to investigate to which extent growthrate and shell chemistry of the blue mussel M. edulis and of juveniles of the ocean quahog A.
islandica are influenced by environmental effects. Our study is complemented using samples
from laboratory growth experiments. These individuals were cultured in five temperature
controlled basins, ranging from 1 to 12°C. Here, temperature should be resolvable as thedominating effect on the growth and on the Ca isotopic composition of similar sized specimens.
The third sample set analysed was collected at several sites in the Baltic Sea characterised bysalinities lower than 15‰. Our data shows that Ca isotope fractionation in A. islandica and M.
edulis is both temperature- and salinity-dependent, with the slope of the temperature-sensitivity
similar to inorganic aragonite precipitates. However, any expected mineralogy-dependent
fractionation, which has been found for inorganic carbonate precipitates, seems to be obscured
indicating that Ca isotope fractionation in bivalve shells is strongly biologically controlled.
Contact Information: Dorothee Hippler, Vrije Universiteit Amsterdam, Faculty of Earth and Life Sciences, De
Boelelaan 1085, NL-1081 HV Amsterdam, Phone: +31 20 5987365, Fax: +31 20 5989941,
Email: dorothee.hippler@falw.vu.nl

48

July 17-21, 2007 z St. Petersburg, Florida USA

Stable Isotopes in Unstable Environments: Probing In Situ Environmental
Conditions of Zebra and Quagga Mussels
Dana H. Geary1, Erik N. Hoffmann1, John W. Valley1, Noriko Kita1, Taka Ushikubo1,
Carol E. Lee2 and Suzanne Peyer212

Department of Geology and Geophysics, University of Wisconsin-Madison, Madison, Wisconsin, USA
Department of Zoology, University of Wisconsin-Madison, Madison, Wisconsin, USA

It has been suggested that successful invasive species evolved their broad environmental
tolerances because of their highly variable source habitats, but few have tested this hypothesis.
Molecular studies have identified Black Sea populations as the source of both zebra and quagga
mussel invasions (Dreissena polymorpha and D. bugensis), rather than other native populations(e.g. in nearby freshwater lakes or the Caspian Sea). Brackish waterways such as the Black Sea
typically exhibit high variability in both temperature and salinity, which supports the hypothesisthat variable habitats yield more successful invaders. Freshwater bodies, however, can exhibit
rapid and significant temperature fluctuations as well. Because zebra mussel source populations
have been identified, zebra mussels provide a rare opportunity to compare habitats to determine
if the brackish source habitat does in fact show greater variability than freshwater non-source
habitats.
To address this hypothesis, we have developed seasonal δ18O and δ13C profiles for zebra mussels
from the Black Sea, two freshwater lakes in Turkey, and Lake Ontario, as well as shallow- anddeep-water quagga mussel morphotypes from Lake Ontario. Shells were treated with hydrogen
peroxide to remove organic material because it has been suggested that heat treatments can altermolluscan shell material. Powder samples were collected from shallow (~100µm) grooves of200-300µm width drilled along visible growth increments using a 500µm bit dremmel tool.
The zebra mussel profiles all show similar variation, suggesting that on a coarse scale all of thesewaterways have similar variability and that higher resolution analyses are needed to contrast
variability between these environments. The shallow-water quagga mussel profile exhibited
smaller variations than the zebra mussel profiles, suggesting that water temperature may be moreconsistent at that locality. Unsurprisingly, the deep-water quagga mussel profile showed minimal
variability and significantly more positive isotope values.
We report on high resolution analyses of one zebra mussel shell using a CAMECA IMS-1280
ion microprobe at the University of Wisconsin-Madison. The IMS-1280 offers significantly
greater spatial resolution (< 10µm, less than mean daily growth), which in turn permits
characterization of fine scale environmental variations for that mussel’s habitat.
Contact Information: Erik N. Hoffmann, Department of Geology and Geophysics, University of WisconsinMadison, 1215 W. Dayton St., Madison, WI 53706 USA, Phone: (608) 262-8960, Fax: (608) 262-0693,
Email: hoffmann@geology.wisc.edu

49

First International Sclerochronology Conference

Antipatharians: High Resolution Recorders of the Oceanographic
Environment
Charles W. Holmes1, Steve W. Ross2 and Noreen A. Buster3
1

USGS., St. Petersburg, Florida
UNC-W, Center for Marine Science, Wilmington, NC
3
ETI Professionals, St. Petersburg, Florida
2

Antipatharian corals are found in all oceans, grow very slowly, subsist primarily on plankton,
and live in water depths from 100 to >1000 meters. Their skeletons are composed of chitin in
annual concentric growth bands similar to tree rings. Because these bands can be separated
easily; the resulting annual samples can provide extremely high temporal resolution for analyses.
Two specimens of Leipathes glaberrina were collected in the western Atlantic Ocean of thesoutheastern United States, one from the Stetson Bank (off South Carolina) and one fromSavannah Lithoherms (off Georgia), They were analyzed for short-lived radioisotopes, 14C, δ13C,
and trace metals. We used 210Pb to date outer bands and 14C to date inner bands. The specimen
from Stetson Bank, collected live from 500 m. depth. The specimen from Savannah Bank wascollected dead but 14C dates indicate that it grew from ~ 2500 BP to approximately ~1000 BP.
210
Pb age models were verified with 14C dates from the outer bands, which yield modern Δ14C
equal to tropical corals in the western Atlantic. The 210Pb coupled with the band enumeration,
indicates a constant coral growth rate of 15µm/year. Using the 210Pb- band count chronology; theconventional radiocarbon age for the band formed in 1950 was ~ 400 years old, the publishedreservoir age for this part of the Atlantic. However, the difference between the estimated age
and the conventional radiocarbon age progressively decreased coalescing at ~ 700 BP. From thispoint till 2500 BP there appears to have be no difference between the 210Pb-band count age andthe conventional radiocarbon age, thus no reservoir effect.
In addition to the carbon isotopes, ICP/MS analysis established that the antipatharians are
extremely enriched in metals, especially micronutrients used by plankton. Comparison of themetal concentrations in the corals to average concentrations in sea water established that the
micronutrients were enriched from two orders of magnitude for cobalt to greater than 6 orders ofmagnitude for cadmium. Assuming that cadmium is a proxy for productivity, the temporal record
demonstrates that during the medieval warm period the productivity of the western Atlantic wassignificantly enhanced, decreasing during the Little Ice Age. For most of the record, gallium anindex of aerosol flux, and cadmium an index of productivity co-varied until 1850, and correlate
well with the dust record in the GISPII core. However, after 1850, cadmium became moreconcentrated, which may be attributed to the burning of fossil fuel, primarily coal.
Whether these preliminary conclusions withstand further review, it is apparent that with theirannual layers, these animals have existed for hundred to thousands of years recording
oceanographic and climatic changes at a very high resolution during the last part of the
Holocene.
Contact Information: Charles Holmes, USGS, 600 Fourth Street South, St. Petersburg, Florida 33701,
Phone: 7270803-8747, Fax 727-803-2032, Email: cholmes@usgs.gov

50

July 17-21, 2007 z St. Petersburg, Florida USA

Assessing Evironmental Factors Associated with Changes in the Growth Rateof Semele casali through the Holocene
R. A. Krause, Jr.1, J. W. Huntley1, M. Kowalewski1, C. S. Romanek2, D. S. Kaufman3 and
M. G. Simoes4
1

Department of Geosciences, Virginia Tech, Blacksburg, VA USA
Savannah River Ecology Laboratory, University of Georgia, Aiken, SC USA
3
Department of Geology, Northern Arizona University, Flagstaff, AZ USA
4
Instituto de Biociências, Universidade Estadual Paulista, Botucatu, São Paulo, Brazil
2

Growth rates of marine mollusks can be influenced by a number of factors that can change overthe lifetime of an organism. In this study we construct sclerochronological profiles of the bivalve
Semele casali, coupled with high resolution LA-ICP-MS trace element data (Mn/Ca, Ba/Ca) toassess the relative effect of environmental conditions on overall shell growth.
This study utilizes time averaged accumulations of shells, dredged from a 30 meter site along theinner shelf of the Southeast Brazilian Bight (western South Atlantic). We employed amino acidracemization calibrated with AMS radiocarbon to date individual shells. The resulting time series
for each site have nearly-complete coverage (at centennial resolution) for the past threemillennia.
Several shells were chosen from the time series for sclerochronological and in situ trace element
analysis. Preliminary results at a single site indicate differences in growth rate between shells of
the same size (7-9 mm) but different ages. For example, a shell from 160 years BP showed 3
periods of slow relative growth (possibly indicating winter growth) with an overall linear growthtrajectory over the relatively short life of the individual. However, a shell from 900 years BP
showed only one period of slow relative growth. Such changes in the growth rates between twootherwise similar shells may be a response to climatic fluctuations in this region over the last
millennium but additional shells must be analyzed to substantiate this interpretation.
Changes in growth rate among individuals may also be linked fluctuating productivity patterns.
The Southeast Brazilian Bight is influenced by non-seasonal productivity pulses caused bycoastal runoff events or by intensified coastal upwelling. Using the relationships between Ba/Caand Mn/Ca, we have identified one shell that shows a runoff-related productivity signature, while
the other shows an upwelling-related productivity signature. Yet, the growth increments for theseshells show no significant correlation with either Ba/Ca or Mn/Ca time series when considered asa whole. However, subsections of the time series for both shells do seem to correlate, suggestingthat growth rate and productivity are, at times, coupled. There are many additional factors toconsider, and future work will incorporate additional geochemical proxies such as δ13C and δ18O
isotopic profiles and additional trace element data to better understand fluctuations in the growthrate among individuals and their implications for environmental change in this region over thelast millennium.
Contact Information: John W. Huntley, Department of Geosciences, Virginia Tech, 4044 Derring Hall, Blacksburg,
VA 24060 USA, Phone: 5402311913, Fax: 5402313386, Email: jhuntley@vt.edu

51

First International Sclerochronology Conference

Recent Salinity Change in the Western Pacific Warm Pool Reconstructed by
Coral Paleo-Salinometer
Hiroko Iijima1, Hajime Kayanne1, Osamu Abe2, Maki Morimoto2 and Toshio Yamagata1
12

Department of Earth and Planetary Science, University of Tokyo, Tokyo, Japan
Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan

A recent freshening trend of the surface seawater in the tropical Pacific has been suggested on
the basis of spatio-temporal analysis of salinity or precipitation data [e.g., Boyer et al., 2005,
Geophy. Res. Lett., 32, L0164]. Because instrumental salinity records were only sparsely
distributed, the freshening trend was only shown for the latitudinal distribution, and thediscussion in longitudinal distribution was insufficient. The tropical Pacific is the birth place ofthe most fundamental climate mode of ENSO, which is driven by the longitudinal difference of
ocean-atmosphere systems, and therefore reconstruction of sea surface salinity (SSS) in theregion is important for understanding the long-term changes in ocean-atmosphere interaction.
Oxygen isotopic composition of coral skeleton (δ18Ocoral) is controlled both by sea surface
temperature (SST) and by δ18O of seawater (δ18Osw), the later of which correlates linearly with
SSS [Morimoto et al., 2002, Geophy. Res. Lett., 29(11), 1540]. Therefore, δ18Osw isreconstructed by removing the contribution of SST from δ18Ocoral, and 50-year SSS variation was
well reconstructed from δ18Ocoral [Iijima et al., 2005, Geophy. Res. Lett., 32, L04608]. In thisstudy, we have reconstructed δ18Osw variation for the recent 50 years in the western Pacific warm
pool (WPWP) region from δ18Ocoral data. Decreasing trend in δ18Osw was indicated clearly in theeastern part of WPWP, whereas such trend was not detected at the northwestern part of WPWP.
This zonal contrast in δ18Osw indicates that an El Niño-like condition is prevailing in the past 50
years and supports a weakening of Walker circulation, which makes the increased precipitationin the eastern part of WPWP, over past decades reported by the observational and modelingstudies [Vecchi et al., 2006, Nature, 441, 73-76].
Contact Information: Hiroko Iijima, Department of Earth and Planetary Science, University of Tokyo, Hongo,
Tokyo 113-0033, Japan, Phone: +81-3-5841-4566, Fax: +81-5841-8318, Email: iijima@eps.s.u-tokyo.ac.jp52

July 17-21, 2007 z St. Petersburg, Florida USA

Looking Younger While Getting 'Colder': Exploring the Role ofHeterochrony in the Evolution of Long-lived Bivalves from the Eocene of
Seymour Island, Antarctica
Devin P. Buick1 and Linda C. Ivany2
1
2

Department of Geology, University of Cincinnati, Cincinnati OH, USA
Department of Earth Sciences, Syracuse University, Syracuse NY, USA

Evolutionary change within the bivalve genus Cucullaea is well recorded in the nearshore
sediments of the Eocene La Meseta Formation of Seymour Island, Antarctica. The large andlong-lived C. raea is abundant in the early Eocene, yet is replaced in the late middle and late
Eocene by the consistently smaller taxon C. donaldi. Previous work using high-resolution stable
isotope profiles has demonstrated that the many pronounced growth bands of Cucullaea areannual, allowing for precise age determinations and documenting extreme longevity in C. raea
(upwards of 130 years). In addition, geochemical studies of Cucullaea and another bivalve
genus, Eurhomalea, have constructed a record of declining mean annual temperature on the
Antarctic shelf through the Eocene, culminating in the onset of glaciation on the continent. The
most rapid and severe episode of cooling is associated with the transition from C. raea to C.
donaldi. Following on this work, the objective of the current research is to explore the potential
role of heterochrony during the transition from C. raea to C. donaldi by quantifying changes inthe size, shape, and lifespan of individuals. The record of evolutionary change together withisotopically-derived climate data will provide a multifaceted, quantitative look into how an
evolving lineage responds to the environmental stress of regional cooling.
Sclerochronology, in combination with isotopic and morphometric analyses, provides an
excellent means of filling in the missing component of many studies of heterochronic change bystandardizing specimens differing in both size and shape to a common age or developmental
stage. Morphometric data are obtained by rotating a camera around the specimen in the directionof growth to photograph and trace the external outlines of progressively older ontogenetic stages
in each individual. Counting and measuring the growth bands of cross-sectioned individuals andcurve-fitting the size-age data with a modified version of the von Bertalanffy growth function
then provides direct age assignments to each digitized outline. This allows the diagnosis of how(or if) selection is favoring specific evolutionary processes by changing the timing ofdevelopment, the rate of development, and/or the age at the termination of growth.
The replacement of C. raea by the smaller C. donaldi may represent 1) dwarfism, showing a
proportional decrease in size of the descendant species while lifespan and shape remain constant,2) paedomorphosis, where the shape of the descendant species becomes juvenilized, with orwithout an accompanying decrease in size and lifespan, or 3) a simple ecophenotypic decrease in
the typical lifespan of C. raea, with no accompanying speciation or anagenetic change.
Preliminary data favor paedomorphosis, showing that the smaller size of C. donaldi results fromboth a decrease in the rate of growth and truncation of lifespan. Acquisition of morphometricdata is ongoing, and will be integrated with additional size-age information to examine whether
the pattern of juvenilization, also recognized in the sole surviving species of Cucullaea, could bean evolutionary strategy for coping with increasing environmental pressures.
Contact Information: Linda Ivany, Department of Earth Sciences, Syracuse University, Syracuse NY 13244 USA,
Phone: 315-443-3626, Fax: 315-443-3363, Email: lcivany@syr.edu

53

First International Sclerochronology ConferencePrimary Isotope Ratios Preserved in a Late Permian Bivalve Allow for Life
History and Paleoenvironmental Reconstructions
Linda C. Ivany1 and Bruce Runnegar2
1
2

Department of Earth Sciences, Syracuse University, Syracuse NY, USA
Department of Earth and Space Sciences and Institute of Geophysics and Planetary Physics, University ofCalifornia, Los Angeles CA, USA

Specimens of the anomalodesmatan bivalve Myonia corrugata were collected from the Late
Permian Kiama Sandstone of the southern Sydney Basin, New South Wales, Australia. The unit
was deposited in a marine shelf environment during the waning of Gondwanan glaciation in thehigh southern latitudes. Cold conditions are suggested by the presence of numerous radial
aggregates of ikaite crystals (glendonites), now dehydrated to calcite, as well as dropstones andglacial debris in the region. Polished sections of the thick (up to 5.5 cm) shells of M. corrugata
exhibit numerous prominent growth bands, and preservation of fine-scale textural details offers
the possibility of preserving the original isotopic composition of Permian marine carbonate.
However, shells are now calcite, and were most likely originally aragonite, thus requiring
diagenetic alteration that should have reset primary isotope values (at least for oxygen). High
resolution microsampling along consecutive, growth-band-parallel paths produced 120 samples
of carbonate powder across nine distinct growth bands (11-19 from the umbo) that were analyzed
for their stable oxygen and carbon isotopic compositions. Results reveal a record of seasonalvariation in both δ18O and δ13C, suggesting that original isotopic composition may be retained,even after ~270 million years and likely isomorphous replacement. δ18O and δ13C generally
exhibit positive covariance, and isotopic minima correspond to the positions of growth bands,
confirming that bands were produced annually. Carbon isotope values are unusually positive(+3‰ to +6‰), but not atypical for the Permian, and become slightly more positive over thenine years recorded in the data. Oxygen isotope values are, not surprisingly, somewhat morevariable than carbon; they average about -7‰, range over ~2.5‰ per year, and show the sameenrichment trend as δ13C. Values this negative suggest the effects of diagenetic alteration, but it
is difficult to imagine how water-mineral reactions could alter δ18O values while maintaining thepattern of seasonal δ18O and δ13C co-variation seen in this shell. It is more probable that shell
compositions are primary, and were influenced by significant, perhaps seasonal, freshwaterrunoff into the coastal setting in which this bivalve was growing. Ongoing SEM and electron
microprobe work may help to resolve questions of primary shell mineralogy and alteration.
A count of growth bands reveals surprising longevity - a minimum lifespan of 55 years. Potential
analogues include the bivalves Cucullaea and Eurhomalea from the Eocene of Seymour Island,
Antarctica, and the modern Arctica islandica from the north Atlantic. All are slow growing,
long-lived bivalves from high-latitude shelves, and all share the stress of a fluctuating foodsource due to seasonal light and phytoplankton availability. The similarities in life history
strategy suggest that long life may be either adaptive in this setting or a predictable consequenceof the unusual environmental conditions in which the clams lived.
Contact Information: Linda Ivany, Department of Earth Sciences, Syracuse University, Syracuse NY 13244 USA,
Phone: 315-443-3626, Fax: 315-443-3363, Email: lcivany@syr.edu

54

July 17-21, 2007 z St. Petersburg, Florida USA

Geographic Variation in Growth Rate and Form of a Jurassic Oyster, and its
Environmental Implications
Andrew L. A. Johnson1, Jingeng Sha2 and Mark N. Liqourish1
1
2

School of Science, University of Derby, Derby, UK
Nanjing Insitute of Geology and Palaeontology, Nanjing, China

Marine bivalves of the Bathonian stage (Middle Jurassic) in NW Europe are smaller than thosefrom earlier and later stages. Johnson (1999) suggested that this might reflect a lowering ofsalinity throughout the area (to the mid-twenties per mil). We have attempted to test the notion ofsuch a reduction by analysing growth-rate and form of the ‘flat’ oyster Praeexogyra hebridica(Johnson et al. 2007). We sampled populations from England representative of environments
ranging from undoubtedly reduced salinity to ‘near-marine’. Age of shells was determined bycounting ligamental growth structures and combined with size information to generate growth
curves. Data were also obtained on shell thickness and overall shape. Growth rate and shell
thickness were found to be lower in a ‘near-marine’ population than in a contemporaneous
reduced-salinity population; shells from the former exhibit, in addition, an ‘etiolated’ form. On
the basis of these findings and supplementary sedimentological and faunal evidence (including
the low growth rate in all sampled populations in comparison to analogous extant oyster genera)
we consider that during the Bathonian offshore environments in NW Europe were characterised
by reduced primary productivity as well as somewhat lowered salinity. Evidence of low growthrate in the oyster Liostrea birmanica from the Bathonian of Tibet suggests that these conditions
may have been widespread. We speculate that environmental constraints on growth in offshore
settings may have driven the Bathonian colonisation by bivalves of strongly reduced salinity, but
probably more productive, marginal-marine environments (Fürsich et al. 1995). Geochemical
tests of the ‘salinity + productivity’ hypothesis are in progress.
References:
Fürsich, F. T., Freytag, S., Röhl, J. and Schmid, A. 1995. Palaeoecology of benthic associations in salinitycontrolled marginal marine environments: examples from the Lower Bathonian (Jurassic) of the Causses(southern France). Palaeogeography, Palaeoclimatology, Palaeoecology, 113, 135-172.
Johnson, A. L. A. 1999. Evidence and cause of small size in Bathonian (Middle Jurassic) marine bivalves of northwestern Europe. Palaeontology, 42, 605-624.
Johnson, A. L. A., Liquorish, M. N. and Sha Jingeng 2007 (in press). Variation in growth-rate and form of a
Bathonian (Middle Jurassic) oyster in England, and its environmental implications. Palaeontology, 50.
Contact Information: Andrew L. A. Johnson, School of Science, University of Derby, Kedleston Road, Derby, DE22
1GB, UK, Phone: +44 1332 591721, Fax +44 1332 597747, Email: A.L.A.Johnson@derby.ac.

55

First International Sclerochronology Conference

Stable-Isotope and Microgrowth-Increment Variation in Shells of the Queen
Scallop from Cool- and Warm-Temperate Settings
Andrew L. A. Johnson1, Annemarie Bird1, Bernd R. Schöne2, Jon Hickson1, Tim Heaton3 andPeter Balson3
1

School of Science, University of Derby, Derby, UK
Institute of Geosciences, University of Mainz, Mainz, Germany
3
British Geological Survey, Keyworth, UK
2Studies of modern and subfossil Queen Scallop (Aequipecten opercularis) shells from theSouthern North Sea Basin (SNSB), western Europe, have shown that oxygen-isotopic
composition is a reliable proxy for temperature in cool-temperate settings (Hickson et al. 1999,
2000; Johnson et al. 2000). We have investigated whether oxygen-isotopic composition is areliable temperature-proxy in warm-temperate settings by combining isotopic analysis of shells
with measurement of microgrowth-increment widths. Pliocene shells from the SNSB supposedly
grew in waters some 5º C warmer than now but their oxygen-isotopic compositions indicate
temperatures little different from present. Microgrowth-increment widths are, however,substantially greater than in modern and subfossil shells from the SNSB, and are comparablewith values from Mediterranean (warm-temperate) A. opercularis. The isotopic compositions ofMediterranean shells confirm suspicions raised by the Pliocene shells over the accuracy of
isotopic temperature estimates in warm-water settings: some yield isotopic temperatures
markedly different from those experienced in life. While in some cases the discrepancy may be
accountable to seasonal fluctuations in isotopic composition of the water, in others the only
reasonable conclusion is that shell deposition involved non-equilibrium isotopic fractionation.
This study confirms the value of combining growth-increment with oxygen-isotope data inpalaeotemperature investigations.
References:
Hickson, J. A., Johnson, A. L. A., Heaton, T. H. E. and Balson, P. S. 1999. The shell of the Queen Scallop
Aequipecten opercularis (L.) as a promising tool for palaeoenvironmental reconstruction: evidence and reasonsfor equilibrium stable-isotope incorporation. Palaeogeography, Palaeoclimatology, Palaeoecology, 154, 325-337.
Hickson, J. A., Johnson, A. L. A., Heaton, T. H. E. and Balson, P. S. 2000. Late Holocene environment of thesouthern North Sea from the stable isotopic composition of Queen Scallop shells. Palaeontologia Electronica, 3(2), article 3, 11 pp (http://palaeo-electronica.org/2000_2/scallop/issue2_00.htm).
Johnson, A. L. A., Hickson, J. A., Swan, J., Brown, M. R., Heaton, T. H. E., Chenery, S. and Balson, P.S. 2000. The
Queen Scallop Aequipecten opercularis: a new source of information on Late Cenozoic marine environments ofEurope. 425-439 In Harper, E. M., Taylor, J. D. and Crame, J. A. (eds) The Evolutionary Biology of the Bivalvia.
Geological Society, London, Special Publications, 177.
Contact Information: Andrew L. A. Johnson, School of Science, University of Derby, Kedleston Road, Derby, DE22
1GB, UK, Phone: +44 1332 591721, Fax +44 1332 597747, Email: A.L.A.Johnson@derby.ac

56

July 17-21, 2007 z St. Petersburg, Florida USA

Characterization and Quantification of Organic and Mineral Contents of Fish
Otoliths using Micro-Raman Spectrometry: Application to European Hake.
A. Jolivet1, J. F. Bardeau2, H. de Pontual1 and R. Fablet1
1
2

Ifremer, STH/LASAA, Plouzané, France
Laboratoire de Physique de l’Etat Condensé, Université du Maine, Le Mans, France

Otoliths are calcareous concretions in Osteichthyans inner ear. Their accretional growth follows
a circadian rhythm and is both physiologically controlled and influenced by environmental
conditions. They act as biological archives providing the basis for the reconstruction ofindividual life traits and thus deliver invaluable information in fisheries sciences and marine
ecology. However in many cases the interpretation schemes remain incomplete and debatable.
New advances in the analysis and understanding of otolith biomineralisation processes are of key
importance to fully exploit the potential of the archive. To this end this communication
investigates the potential of micro-Raman spectrometry with a view to quantitatively analyzing
physico-chemical characteristics of fish otoliths both at micro-and macro-scales.
Raman spectrometry is a non destructive technique providing dynamic and structural information
on materials. By measuring the interaction of monochromatic laser light with chemical bonds
within the sample, this technique was commonly used for detection, quantification of local
variation in molecular structure of matrix and mineral fractions. It has been shown to be areliable technique for quantitative determination of polymorph calcium carbonates. In our study,
we further demonstrate that micro-Raman spectrometry (Jobin-Yvon T64000) combined with aconfocal system and a motorized microscope stage delivers high-resolution characterizations of
the mineral and organic composition of fish otoliths.
High spatial selectivity (down to 1µm), spectral resolution and detector sensitivity of microRaman spectrometry enable the L-zone and D-zone analysis which constitute a micro increment
in fish otoliths. Our experiment focused on otolith thin sections of European Hake (Merluccius
merluccius). Preliminarily, parameters of analyses were defined: use of a 514.5 nm wavelength
radiation from an argon/krypton ion laser, surface laser powers of 50 mW minimizing laser
induced heating of sample. An accumulation time of 60 s to 120 s and 4 scans were used whichgave adequate signal-to-noise ratio of spectra. The scan ranges were 120-4000 cm-1. Aragonite
spectrum was characterized by 14 peaks with a strong one at 1086 cm-1. For organic matter, weconcentrated on the band at 3388 cm-1, characteristic of O-H bonds. Relative intensity ratio
between surfaces of these two characteristics peaks makes it possible to quantify the differenceof composition between opaque and translucent macrostructures. We founded that translucent
zone have a higher mineral fraction (ratio = 0.64) than opaque zone (ratio = 0.49). Quantitative
differences were shown between L-zone and D-zone with ratios equal to 0.54 and 0.48. Raman
spectra clearly show the existence of two bands at 559 cm-1 and 625 cm-1, which do not belong toaragonite spectrum. The relative intensity ratio differs by a factor 2 between L- and D- zones.
These bands enable the positioning of micro increments on growth axis even during depth
analysis.
Contact Information: A. Jolivet, Ifremer, Laboratoire de Sclérochronologie des Animaux Aquatiques, STH/LASAA,
BP 70, 29280 Plouzané, France. Phone: (+33) 298224964, Email: Aurelie.Jolivet@ifremer.fr

57

First International Sclerochronology Conference

Isotopic Evidence for Variable Climate and Longevity in Modern andArchaeological Coquina Clams, Donax variabilis, from Northeast Florida
Douglas S. Jones and Irvy R. Quitmyer
Florida Museum of Natural History, University of Florida, Gainesville, FL, USA

Donax variabilis, the variable coquina clam, has been a common inhabitant of exposed sandy
beach intertidal and shallow subtidal zones in the southeastern United States throughout the
Pleistocene and Holocene. It is ideally suited for paleotemperature studies because it is restricted
to environments of well-mixed, normal-marine seawater with a fairly uniform isotopic
composition. As a result, oxygen isotopic variability in D. variabilis shells is largely explainedby temperature variation. Although D. variabilis is small and short-lived, its shell represents animportant paleoclimate archive because of its unique habitat preference. High-resolution
sampling and analysis of three modern shells reveals a close correspondence between
isotopically-determined water temperatures and historical water temperatures during the springsummer growing season. Paleotemperature profiles of two Northeast Florida Preceramic
Archaic Period shells (ca. 4240 & 5570 14C yr BP) and two Orange Period Archaic shells (ca.
3600 & 3760 14C yr BP) yield paleotemperatures that average 3.5 °C higher than present
summer-autumn water temperatures. These warm paleotemperatures highlight seasonality
differences associated with the mid-Holocene Hypsithermal climatic interval in this region. One
shell excavated from a site that dates to the early Little Ice Age yielded a counter-intuitive
paleotemperature profile -- sea surface temperature was warmer than present day with greater
seasonality. The data show that the longevity of the modern and Archaic Period shells extends
between three and six months. However, the Protohistoric Donax shell appears to have lived formore than a year.
Contact Information: Douglas S. Jones, Florida Museum of Natural History, University of Florida, Gainesville, FL
32611, USA, Phone: 352-392-1721, FAX 352-392-8783, Email: dsjones@flmnh.ufl.edu

58

July 17-21, 2007 z St. Petersburg, Florida USA

Holocene and Last Interglacial Paleoceanography in the Pacific Subtropical
Gyre from Coral Annual Bands of Okinotori-shima Island, Northwestern
Subtropical Pacific Ocean
Hajime Kayanne, Shuhei Abe, Hiroko Iijima and Nobuko Nakamura
Department of Earth and Planetary Science, University of Tokyo, Tokyo, Japan

Mid-Holocene (7300 years B.P.) and Last Interglacial paleoceanography was reconstructed byannual band analysis of present (living) and fossil Porites corals from Okinotori-shima Island
located in the northwestern tropical Pacific Ocean and represents average conditions of thesubtropical gyre.
Time lag of the peaks between 13C and 18O in the present coral is 2 months both in summer andwinter, which reflects the lag between insolation (peaked at June) and SST (August) in thepresent climate. On the other hand, the time lag recorded in the Holocene coral was 1 month insummer, and 2.8 months in winter; the lag recorded in the Last Interglacial coral was 3.9 months
in summer and 3.4 months in winter. The shorter time lag in Holocene summer corresponds tothe delayed insolation peak (July) during this period. The longer time lag in the Last Interglacial
period is derived from the larger seasonal variability in insolation and the delayed response of
SST to insolation during this period.
The average values of 18O were 1.0‰ and 0.92‰ heavier in Holocene and the Last Interglacial
corals, respectively. The heavy oxygen isotope values resulted from heavy 18O values ofseawater (as corresponding to high sea surface salinity) and/or cooler sea surface temperature.
Strong land-ocean temperature contrast and resultant intensified wind field was shown in thesubtropical northwestern Pacific from mid-Holocene corals [Morimoto et al., 2007, QuaternaryRes., 67, 204-214]. The heavy 18O values with the same magnitude in the Last Interglacial coralinfers that the same paleoceanographic condition prevailed over the northwestern subtropicalgyre during this period.
Contact Information: Hajime Kayanne, Department of Earth and Planetary Science, University of Tokyo, Hongo,
Tokyo 113-0033, Japan, Phone and Fax: +81-3-3814-6358, Email: kayanne@eps.s.u-tokyo.ac.jp

59First International Sclerochronology ConferenceHigh-resolution Isotope Profiles of Walleye Pollack (Theragra chalcogramma)
Otoliths from the East Sea: Tracing Habitat Environmental Conditions
Boo-Keun Khim1 and William P. Patterson2
1
2

Division of Earth Environmental System, Pusan National University, Busan, Korea
Saskatchewan Isotope Laboratory, Department of Geological Sciences, University of Saskatchewan, Saskatoon,
CanadaHigh-resolution δ18O and δ13C profiles were obtained from two pollack (Theragra
chalcogramma) otoliths. Two specimens (BK23 and BK25) were collected in Nov. 1998 and inFeb. 2000, respectively, from offshore of Korea in the East Sea. Both δ18O and δ13C profiles of
the two specimens display distinct patterns of variation each of which can be evaluatedindividually. Specimen BK23 exhibits a gradual increase in both δ18O and δ13C values from thecore to the margin, with fluctuations corresponding to the annual growth variability. Specimen
BK25 displays a similar pattern of isotope variation without the rapid increase from the core in
the inner part. Annual variations in δ18O and δ13C values are comparable in both specimens,
providing a record of environmental conditions, in spite of obvious discrimination between theabsolute values. The δ18O and δ13C values of specimen BK25 are higher by more than 0.5‰,
compared to those of BK23. Such distinctive values are indicative of different environmental
conditions (e.g., water depth, migration route, etc.) during growth in the East Sea. Our results
urge caution in utilization of single otolith isotope profiles as representative of general habitat ofwalleye pollack in the East Sea.
Contact Information: Boo-Keun Khim, Division of Earth Environmental System, Pusan National University, Busan609-735, Korea, Phone: +82-51-510-2212, Fax+82-51-571-2963, Email: bkkhim@pusan.ac.kr

60

July 17-21, 2007 z St. Petersburg, Florida USA

Stable Isotope Profiles of Fossil Molluscs from the Lower Pleistocene
Seoguipo Formation (Korea) and Paleoseasonality Variation
Boo-Keun Khim1, Jin Kyung Kim2, Kyung Sik Woo2 and Seok Hoon Yoon3
1

Division of Earth Environmental System, Pusan National University, Busan, Korea
Department of Geology, Kangwon National University, Chuncheon, Korea
3
Department of Oceanography, Cheju National University, Jeju, Korea
2High-resolution δ18O profiles of six fossil bivalves (Mizuhopecten tokyoensis hokurikuensis)
from relevant stratigraphic units separated by sequence boundaries in the shallow-marine
sedimentary deposit of the Lower Pleistocene Seoguipo Formation (Korea) exhibit distinct
annual cycles, recording the unique seasonality, i.e., δ18O amplitude. The direct comparison offossil δ18O profiles with those of living shells (Amusium japonicum japonicum and Vesticardium
burchardi; present-day condition) indicates a different paleoenvironment during the depositionof the lower part of formation. The positive δ18O shift in the isotope profile of the fossil
specimens relative to those of the living mollusk shells reflects lower paleotemperature than
today. Judging from the winter temperatures by the heaviest δ18O values, however, thetemperature variation cannot account for the whole positive δ18O offset. It means that variationof seawater δ18Ow values appears to play a dominant role in the biogenic carbonate precipitation
during the deposition of formation. Thus, the individual fossil shell at each stratigraphic unit
represents different paleoenvironmental conditions related to the lower temperature and 18Oenriched glacial seawater. In terms of δ18O amplitudes inferred from the fossil isotope profiles,
their changes within the formation might reflect the fluctuation of paleoseasonality during theperiod of the lower half of the Seoguipo Formation.
Contact Information: Boo-Keun Khim, Division of Earth Environmental System, Pusan National University, Busan609-735, Korea, Phone: +82-51-510-2212, Fax+82-51-571-2963, Email: bkkhim@pusan.ac.kr

61

First International Sclerochronology Conference

Modeling Oxygen-Isotope Ratios in an Estuarine Bivalve, Saxidomus
Gigantea: Insights into Holocene Climate Change in Coastal British
Columbia, Canada
Andrew W. Kingston1, Darren R. Gröcke1 and Aubrey Cannon2
12School of Geography and Earth Sciences, McMaster University, Hamilton, Ontario, Canada
Department of Anthropology, McMaster University, Hamilton, Ontario, Canada

Shell middens at archaeological sites have the potential to provide us with high-resolution
records of past climatic and environmental conditions during the time of occupation. In thisstudy we analyze the bivalve, Saxidomus gigantea, from an estuarine setting at Namu, British
Columbia, Canada. Stable isotopic ratios in this environmental setting are complicated by bothseasonal variations in river discharge and temperature fluctuations. Therefore, a mass-balance
model delineating the sources and partitioning of oxygen-isotopes in S. gigantea was developed.
The isotopic composition and temperature of marine and fresh water within the Namu region wasmeasured and directly compared with oxygen-isotope ratios from modern S. gigantea. Our massbalance model suggests that the oxygen-isotope composition of S. gigantea is dominated bychanges in freshwater input related to seasonal variations in precipitation and river discharge. We
then applied this mass-balance model to a 6,000-year record of S. gigantea from a shell midden
at Namu to determine precipitation fluctuations in region during the Holocene. This analysis
indicates that a period of enhanced precipitation and river discharge occurred between 4,000–
2,000 years BP, which tends to corroborate other regional and even global records ofprecipitation during this time interval. In order to generate more accurate reconstructions using
sclerochronology in archaeological shell middens, it is pivotal that modern water and bivalve
samples be processed and analyzed for their isotopic composition a priori any archaeologicalinvestigation and subsequent reconstruction.
Contact Information: Andrew W. Kingston, Stable-Isotope Biogeochemistry Laboratory, School of Geography and
Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Phone: (905) 525-9140
ext. 24384, Fax: (905) 546-0463, Email: kingstaw@mcmaster.ca

62

July 17-21, 2007 z St. Petersburg, Florida USA

Source Effects on the Carbon-Isotope Variation in an Estuarine Bivalve,
Saxidomus gigantea
Andrew W. Kingston1, Darren R. Gröcke1, Aubrey Cannon2 and Meghan Burchell2
1
2School of Geography and Earth Sciences, McMaster University, Hamilton, Ontario, Canada
Department of Anthropology, McMaster University, Hamilton, Ontario, Canada

Our understanding of carbon-isotope variation in bivalve sclerochronology is limited due to therole of species-specific and environmental mechanisms. In this study we provide a synopsis ofcarbon-isotope sources that contribute to the cyclic carbon-isotope variation in the bivalve,
Saxidomus gigantea, at Namu, British Columbia, Canada. High-resolution intra- and interincremental stable-isotope analysis of modern S. gigantea was performed to produce Hendy Test
(radial) and seasonal profiles in oxygen and carbon, respectively. Inter-incremental carbonisotope profiles exhibit an “out-of-phase” (lag) relationship with the seasonal cycle recorded inoxygen isotopes. The oxygen-isotope profiles in S. gigantea at Namu are interpreted as being
dominantly controlled by freshwater fluxes throughout the year. Intra-incremental isotopic
analysis (i.e., Hendy Test) exhibited significant variation (>1‰). Therefore, in order to produce agreater understanding of this lag and cyclic variation, the carbon-isotope composition of various
biologic and inorganic components in the environmental system were analyzed. The isotopic
profiles generated in S. gigantea from Namu were compared against the isotopic analysis of: (a)tissues/organs within S. gigantea, (b) dissolved organic carbon (DOC), and (c) dissolved
inorganic carbon (DIC) from marine and fresh waters. An isotopic comparison between thesecomponents provides a fractionation model that suggests a combination of biological andenvironmental factors that affect the intra-shell carbon-isotope variability. This study illustrates
the need to investigate carbon-isotope variability in both the organic and inorganic phases of aregion in order to adequately interpret sclerochronological carbon-isotope records.
Contact Information: Andrew W. Kingston, Stable-Isotope Biogeochemistry Laboratory, School of Geography and
Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1, Phone: (905) 525-9140
ext. 24384, Fax: (905) 546-0463, Email: kingstaw@mcmaster.ca

63First International Sclerochronology Conference

A Marine Carbonate Reference Material for Microanalysis
Alan E. Koenig and Stephen A. Wilson
US Geological Survey, Mineral Resources Program, Denver, CO, USAA critical requirement to quantitative analyses of virtually every analytical technique is theexistence of reference materials of known concentration and matrix. A particular challenge formicroanalytical techniques such as laser ablation ICP-MS (LA-ICP-MS) is that the material used
for calibration and/or quality control must be of similar matrix to the samples being studied andmust be homogeneous at the scale of analysis. Since the scale of analysis can often be smaller
than 50 micrometers, the preparation of materials available to the international community canbe difficult.
Using a co-precipitation recipe developed for the purpose of producing homogeneous powders, a
new marine carbonate reference material has been produced at the USGS. This material is a
CaCO3 matrix with elevated levels of Mg, Na, Fe, Sr and Mn and a range of concentrations ofnearly all trace elements of interest in marine carbonate studies. Available as pressed pellets (nobinder) this material will be useful for calibration and quality control for a wide range of marine
carbonate studies utilizing LA-ICP-MS.
Reference values for this material will be presented. Effects of laser wavelength, matrix effects
and homogeneity data will be presented. Information regarding the availability of this referencematerial will be available at the time of presentation.
Contact Information: Alan Koenig, USGS, Denver Federal Center, MS973, Denver CO, 80225, USA,
Phone: 303-236-2475, Fax: 303-236-3200, Email: akoenig@usgs.gov

64

July 17-21, 2007 z St. Petersburg, Florida USA

Trace Element Mapping of Otoliths by Laser Ablation ICP-MS:
Transportation, Migration and/or Vaterite? (and a Good Look at the
Methods)
Alan E. Koenig1 and Daniel Gibson-Reinemer2
1
2

US Geological Survey, Mineral Resources Program, Denver, CO, USA
Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO, USA

Otolith microchemistry reflects primary incremental structure recorded during the lifetime of thehost fish. Critical evaluation of otolith microchemistry requires an understanding of the within
otolith chemical heterogeneity. Possible mechanisms for chemical heterogeneities include
changes in water chemistry, transportation, migration and changes in crystallographic structure.
While much work has already been done utilizing laser ablation ICP-MS (LA-ICP-MS) for
minor and trace element determinations in otoliths for these types of studies, significant room forminimizing complications from complex heterogeneities exists. Utilizing rapid LA-ICP-MS traceelement mapping protocols, it is now possible to image the chemical heterogeneities of the entire
otolith or a region of each otolith sample.
Detailed trace element maps for a single rainbow trout (Oncorhynchus mykiss) otolith reveal
chemical signatures indicative of the hatchery origin and later wild release. Additional
heterogeneity exists within this otolith due to the presence of vaterite, a less common polymorphof CaCO3. While previous workers have discussed the presence of vaterite, the utility of vaterite
containing otoliths has been questioned. While certainly the vaterite signature complicates thecomparison of populations containing aragonite only and aragonite plus vaterite samples, traceelement maps reveal certain internal structure within the vaterite regions that may prove useful.
Strontium and Mn show two chemically distinct regions within the aragonite portion of thissample, with a third chemical zone within the vaterite region of the otolith. Barium and Zn show
three distinct chemical zones all within the aragonite portion of the otolith and a fourth chemicalzone that comprises the vaterite portion of the otolith. Sodium and Mg all show uniform
chemistry across the aragonite region with a different and zoned chemical signature within thevaterite. Magnesium and Mn both show internal zoning within the vaterite region that parallels
the direction of growth within the otolith. Additional 2-D mapping and traditional spot or line
scan analyses for other trout otoliths will also be presented.
Details regarding the LA-ICP-MS methods including the USGS microanalytical carbonate
reference materials, laser sampling protocol and data processing will also be presented.
Contact Information: Alan Koenig, USGS, Denver Federal Center, MS973, Denver CO, 80225, USA,
Phone: 303-236-2475, Fax: 303-236-3200, email: akoenig@usgs.gov

65

First International Sclerochronology Conference

Shell Formation in Mytilus edulis: Interactive Effects of Temperature, Salinity
and Food Availability
Ute Kossak and Martin Wahl
IfM-GEOMAR Leibniz Institute of Marine Sciences, Düsternbrooker Weg 20, D- 24105 Kiel, Germany

Bivalves, as many other calcifying organisms, memorize environmental conditions in their shellmaterial. Temperature, salinity and other parameters alter the process of bio-mineralization andcan be reflected in growth increments, shell composition and shell stability. Climate change
models for the coming 50 years predict warming, salinity shifts and altered nutrient regimes for
the Baltic Sea, which can be expected to affect the ecosystem and its inhabitants in various ways.
Predictions of future bivalve performance can be made, if we know how the shell forming
process reacts to different environmental conditions.
In a 3-factorial laboratory experiment we tested how salinity, temperature and food availability
affect mussel shell growth and shell stability, with a special attention to the interactions among
the tested factors. We found significant impacts on growth rates of all 3 factors, and significant
effects of salinity and temperature on shell stability. The interactions among factors weresignificant as well. Additionally, a multiple transplant experiment was run in the field. The
translocation to another salinity-region simulated the predicted changes in salinity. Mussels from
populations along the Baltic salinity gradient (33, 29, 24, 17, 12 and 6 psu) were exchanged
reciprocally between 6 stations. In Mytilus, highest growth rates occurred at 25 psu. In thissalinity, a rise in temperature up to 25°C did not affect growth. At very low (15 psu) or high (35psu) salinities, however, temperatures higher than 20 °C led to a significant decrease in growth
rates.
Our results indicate that while single mussel properties are influenced by single climate change
parameters in predictable ways, the simultaneous change of more than one climate parameter
may produce unexpected effects. This underlines the importance of considering multi-factor
interactions when studying global change impacts.
Contact Information: Ute Kossak, IfM-GEOMAR Leibniz Institute of Marine Sciences, Düsternbrooker Weg 20,
D-24105 Kiel, Germany. Email: ukossak@ifm-geomar.de66

July 17-21, 2007 z St. Petersburg, Florida USA

Cathodoluminescence Sclerochronology of Mollusc Shells: A Tool for
Seasonal Contrasts Estimate through Geological TimeFranck Lartaud1, Laurent Emmanuel1, Marc de Rafelis1, Michel Ropert2, Eric Verrecchia3 andMaurice Renard1
1

UPMC; JE2477 Biominéralisations & Paléoenvironnements, Paris, France
DRV/RA LERN – Laboratoire Environnement Ressource de Normandie, IFREMER, Port-en-Bessin, France
3
Université de Neuchâtel; Institut de Géologie et d’Hydrogéologie, Neuchâtel, Switzerland
2

In order to better comprehend future environmental evolution, the analysis of past climatic
events requires a perfect knowledge of the phenomena between the dynamics of the environment
and the biosphere. Characterization of global changes needs to determine the influence of theircontrol factors according to temporal high resolution (seasonal to daily). It is essential toestablish a sufficiently relevant database to increment past and current climatic models. The
accretionary growth of mollusc shells makes it possible to obtain recordings of the history of thelife of these organisms. The chemical analysis of the shells along a sclerochronological profile
gives precise information on the seasonal evolution of (paleo)environmental and (paleo)climaticconditions. Nevertheless, it is necessary to develop an evaluation of biomineralization processes
independently of environmental fluctuations.
Such an approach was developed on the Crassostrea gigas oyster (Thunberg, 1793) of theEuropean Atlantic coast. A genetically homogeneous population was bred at the oyster station of
Port-en-Bessin (Normandy, France). At the same time, a daily follow-up of environmental
conditions (temperature, salinity and oxygenation rate) was carried out with the use of a multiparameter probe implanted on the breeding site and δ18Osw was estimated by sea water analysis.
An experimental chemical Mn2+ marking of the shells was carried out every two months in orderto have a sufficiently precise temporal adjustment during growth. The cathodoluminescenceanalysis (CL) of the shells reveals a natural fluctuation of luminescence intensity throughout thegrowth of the organisms. The recognition of Mn2+ markings with CL allows the identification ofseasonal to daily cycles of the natural variations of shell luminescence. This sclerochronologic
approach offers new prospects in the study of current and fossil mollusc shell population
dynamics (Lartaud et al., 2006). Moreover, this process permits a micro-sampling strategy forthe geochemical analysis of the shells, so as to reconstruct climatic and environmental variations.
The comparison of the high resolution δ18O fluctuations of these shells with sea watertemperature recordings, confirms the possibility of using this proxy to reconstitute the evolutionof seasonal thermal contrasts. The same approach was developed on an oyster shell dated fromthe late Paleocene. The combination of the cathodoluminescence analysis and isotopic records ofthis shell, allows the refinement of the paleoclimatic reconstructions for this period. Thus, theresults show the emergence of a monsoon-like tropical climate in Western Europe at the end of
the Paleocene.
In conclusion, cathodoluminescence and geochemical coupled analysis of molluscan shells giveaccurate information in the estimation of seasonal contrasts in coastal sea water. This approach
offers new perspectives to study highly fluctuating environmental locations like estuaries or
lagoons, for present and geological times.
Contact Information: Franck Lartaud, UPMC ; JE2477 Biominéralisations & Paléoenvironnements, Case postale
116, 4 place Jussieu, 75252 Paris cedex 05, France, Phone : 01.44.27.49.95, Fax : 01.44.27.38.31,
Email : lartaud@ccr.jussieu.fr67

First International Sclerochronology ConferenceHigh-Resolution Calibration of Geochemical Proxies in the Shell of aLaboratory Grown Giant Clam (Tridacna squamosa)Claire E. Lazareth1, F. LeCornec1, M. Elliot2 and G. Cabioch3
1

UR Paléotropique, Institut de Recherche pour le Développement, Bondy, France
University of Edinburgh, U.K
3
UR Paléotropique, IRD, Nouméa, France
2

This study aims to develop the use of giant long-lived marine bivalves from the Pacific Ocean toreconstruct past environments and obtain information on past climatic changes. Tridacnids wereused because paeoclimatic proxies could provide useful data for archaeological studies in the
Pacific as old shells are often found in the sites (tools, food). Geochemical analyses of suchshells may give information on environmental conditions of living organisms during the old
Human periods.
Calibration of modern giant clams was performed to analyze the relative control ofenvironmental/physiological factors on growth and chemical composition of the shells. Such a
study is necessary to validate data in modern environments in order to use old shells as
environmental recorders. We present here results obtained in a Tridacna squamosa specime
which partly grew in a tank at the Aquarium of Nouméa in New-Caledonia (South-West Pacific).
Environmental parameters like Sea Surface Temperatures (SST), Sea Surface Salinities (SSS),
and photons were regularly recorded during this experiment. Staining by calcein was performed
to have a temporal mark in the shell. At the end of the experiment, the shell was taken to perform
trace elements and stable isotopes analyses at a resolution of seven samples per month.
The mark obtained by calcein in T. squammosa give us the opportunity to reconstruct the daily
growth of the shell. A couplet of dark and translucent bands indicates a day. Broad translucent
bands can be also observed, close to cavities or other anomalies over the shell surface but
difficult to interpret at this day. Geochemical sampling was made according tosclerochronological examination. δ18O measurements in T. squamosa clearly reflect SST
variations at a weekly resolution. Mg content variations are partly negatively correlated to SST
whereas kinetic effects on Sr incorporation seem to be significative. This first calibration study
on T. squamosa confirms that this species of giant clam can be a reliable SST recorder.
Contact Information: C.E. Lazareth, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France, Phone : 00-33-1-48-02-59-64, Fax : 00-33-1-48-02-55-54, Email : claire.lazareth@ird.fr

68

July 17-21, 2007 z St. Petersburg, Florida USA

Microstructural and Geochemical Patterns at the Nyctemeral Scale in theConcholepas concholepas (Gastropoda) Shell
Claire E. Lazareth1, N. Guzmán1, F. Poitrasson2, L. Ortlieb1 and J.-P. Cuif3
1

UR Paléotropique, Institut de Recherche pour le Développement, Bondy, France
UMR LMTG (CNRS-IRD-Univ. Toulouse), Toulouse, France
3
UMR IDES (CNRS-Univ. Paris XI), Orsay, France
2

In paleoclimatic studies for which ocean sea-surface temperature (SST) is a key parameter,mollusk shell geochemical composition is increasingly used as recorder of former environmental
conditions. However, it is becoming quite clear that the calibration of proxies species by species
is an unavoidable prerequisite before any paleo-environmental reconstruction.
We analyzed geochemical variations of a fast growing gastropod, Concholepas concholepas, ona short time window but at a daily to subdaily resolution. Precise temporal framework in theshell was provided by successive fluorescent staining. A high-resolution study on Mg variations
was performed at a subdaily resolution on 1½ month of growth of a laboratory-grown individual.
A mapping of Mg and S spatial distribution within the biocarbonate formed during a 2- day ofshell growth was also obtained.
Shells submitted to periodical fluorochrome markings showed that the biomineralization processof C. concholepas takes place at a hourly rhythm: a 2 µm layer is formed every 0.5 to 3 hours. In
addition, it was established that, every day, a couplet of a thin dark layer and a broadertranslucent layer is formed. Dark increments correspond to growth during the night and areorganic rich zones as evidenced by the S map. Growth rate and Mg incorporation into the shellchange systematically between night and day growth episodes. During the day, Mg isincorporated at a higher rate than at night and this intake is partly correlated with ambient watertemperature. The nightly reduced Mg incorporation is seemingly related to metabolicallycontrolled processes, formation of organic-rich shell increments and nocturnal increased activityof the animals. The positive correspondence between the S and the Mg map tends to indicate thatat least part of the Mg is linked with the organic matrix of the shell.
The nyctemeral Mg changes in the C. concholepas shell evidenced in this study and the link
between Mg and the organic matrix might explain at least part of the discrepancies observed inprevious studies on the use of Mg as a SST proxy in mollusk shells.
Contribution of the CONCHAS (PNEDC), CENSOR (6th PCRD) and BioCalc (ESF) projects.
"This study was financed and conducted in the frame of the EU-project CENSOR (Climate
variability and El Nino Southern Oscillation: Impacts for natural resources and management,
contract 511071) and is CENSOR publication 0095".
Contact Information: C.E. Lazareth, UR Paléotropique, Centre IRD-Ile de France, 32 avenue Henri Varagnat, 93143
Bondy Cedex, France, Phone : 00-33-1-48-02-59-64, Fax : 00-33-1-48-02-55-54, Email : claire.lazareth@ird.fr69

First International Sclerochronology Conference

ENSO, Eastern Tropical Atlantic Temperature Anomalies and Coral Growth
Ruy K. P. Kikuchi1, Marilia D.M. Oliveira1, Carlos A.D. Lentini2 and Zelinda M.A.N. Leão1
1
2

Geophysics and Geology Research Center, Federal University of Bahia, Salvador, BA, Brazil
Institute of Physics, Federal University of Bahia, Salvador, BA, Brazil

Latest bleaching events (1997-1998 and 2003) and sea temperature anomalies suggest that ENSO
has some degree of influence in Eastern Tropical Atlantic coral reefs. This influence and its
impact on coastal ecosystems must be urgently assessed. The use of coral skeleton as
temperature proxies are important tools to produce a consistent SST time series and to evaluate
the impact of global climate change impinged on these ecosystems. Calibration of this proxy are
made using in-situ observational records of SST in Eastern coast of Brazil, and AVHRR
Pathfinfer Version 5.0 satellite derived monthly SST data. The observational data were collectedin Santa Barbara Island (Abrolhos Bank, Brazil – 17°59’S and 38°42’W) at sea surface andsatellite infrared data, were obtained using nightime algorithm to avoid diurnal heat bias. The
study period spans from 1973 to 2003. SST anomalies occurred in Abrolhos in 1986-1988, 19941995, 1997-1998 and 2002-2003, and coincide with ENSO events. On the other hand, the 19901993 ENSO event does not relate to any anomaly in the time series we obtained. Three coral(Mussismilia braziliensis) cores, from Abrolhos Reefs, near Santa Barbara Island, were sliced,
X-radiographed and and its density analyzed with computerized tomography. The X-radiographs
yielded extension rates of 7.7 ± 0.9 mm. There is no clear relationship among SST anomalies andcoral linear extension rates anomalies, even during the last two ENSO related warming episodes,
when bleaching occurred in those reefs. On the other hand, calcification (obtained as the productof extension rates and skeletal density) and temperature seem to be inversely correlated along the
focused period. A slight tendency of reduction both in extension rate and in calcification is
identified.
Contact Information: Carlos Lentini, Federal University of Bahia/UFBA,Travessa Barao de Jeremoabo, s/n, Fisica
da Terra e do Meio Ambiente, Salvador, BA, 40170-280 Brazil, Phone: +55 71 3263 6680, Fax: +55 71 3263-6604,
Email: cadlentini@gmail.com

70July 17-21, 2007 z St. Petersburg, Florida USA

Hydrothermal Vent Mussels as Recorders of Environmental Change
C. A. Richardson, J. Libertinova, L. J. Clarke, H. Kennedy and P. R. Dando
School of Ocean Sciences, College of Natural Sciences, University of Wales Bangor, Menai Bridge,
Anglesey, UK

The shells of many bivalve species have been shown to contain high resolution seasonal recordsof shell growth and environmental conditions across different geographical locations stretchingfrom estuaries to coastal waters and to the deep oceans. Hydrothermal vent mussels
Bathymodiolus sp. live under conditions of continuous darkness, close to vents discharging hot(≤10-350°C) vent fluid enriched in various metals, dissolved methane and sulphide. The mussels
have been shown to experience seawater temperature fluctuations between 5°C and 15°C on thetimescale of seconds to days. This temporal variability in the environment has the potential to berecorded in the geochemical composition of the shell, whilst fluctuations in shell geochemistry
may reflect changes in the shell growth rates and formation of internal shell growth bands.
In this study we present data on the periodicity of the growth banding and data on thegeochemistry (δ18O, δ13C and element/Ca ratios) in the shells of Bathymodiolus azoricus andBathymodiolus puteoserpentis from Menez Gwen and four other vent fields along the MidAtlantic Ridge (MAR) which could provide high resolution records of changes in their growthand environmental settings.
No apparent periodicity was observed in the formation of the microgrowth increments (5-40 μm)
in suitably prepared polished and etched shell sections of B. azoricus. Elemental analyses (Mn,
Rb, Mo, Ag, Sb, Cs, Ba, Ta, Tl, U, heavy metals and rare earth elements) of drilled shell calcium
carbonate powder taken along the growth axes of shells demonstrated there was greater interfield variation in the elemental composition between shells from Menez Gwen and four othervent fields than the intra-mussel shell variation. These findings suggest that mussel shells arerecording different chemical signatures from the different vent fields.
Contact Information: Jitka Libertinova, School of Ocean Sciences, College of Natural Sciences, University of Wales
Bangor, Menai Bridge, Anglesey, LL59 5AB, Phone: +44-1248-382874, Fax: +44-1248-716367,
Email: oss205@bangor.ac.uk

71

First International Sclerochronology Conference

Recent Atlantic and Fossil Mediterranean Acesta Spp. Bivalves as
Environmental Archives for the Deep-Sea
Matthias López-Correa1, A. Freiwald1 and M. Taviani2
1
2

IPAL, Institute of Palaeontology, University of Erlangen-Nuremberg, Erlangen, Germany
CNR-ISMAR, Istituto di Scienze Marine, Bologna, Italy

Recent Acesta excavata (Bivalvia, Limidae) are found in bathyal waters from Northern Norway(72°N) to the Gulf of Guinea (2°S), frequently together with cold-water corals, like Lophelia
pertusa. Their principal distribution is the Norwegian Sea and fossil A. excavata are found in
Last Glacial Mediterranean deposits. Most Acesta species live as filter-feeders, byssally attached
to hard substrates like rocks or coral frameworks. Adult specimens of Acesta attain shell heightsof 8 to 13 cm within the first 20 to 30 years of their life-span. Their external calcitic shell layershows an annual banding, which offers wide stable isotope sampling intervals. These increments
are widest at the main growth axes (0.5-1.0 cm) and thinnest near the hinge (~0.2 cm). The thininternal aragonitic layer has a very regular seasonal banding at the ligament attachment zone.
Acesta excavata from sites with different temperatures and salinities along a latitudinal transect
have been sampled along the main growth axes and at the hinge. The heaviest oxygen isotope
values are always precipitated at equilibrium, while the main growth axes shows clear signs of
biological fractionation. In Trondheimfjord (Mid-Norway) an ontogenetic isotope-transect across
12 increments could be directly compared with a long-term temperature and salinity record withmonthly resolution. The variability patterns of oxygen isotopes match with the seawater
variations and confirmed the annual character of the banding. The absolute temperature range,
reconstructed from the oxygen isotopes over-exaggerates the actual temperature variability, andpoints to strong vital effects at this eutrophic site. The contemporaneous measurement of thecorresponding increments at the hinge yielded instead equilibrium values and allowed thus toestimate the degree of kinetic fractionation in the main growth axes. Relative intra-annual
variability can thus be resolved despite kinetic vital effects and the hinge shows the absolutetemperature range. Acesta species from tropical latitudes (e.g. A. colombiana / Southern
Caribbean) display for most of the shell calcite oxygen isotope values at equilibrium. At theseoligotrophic sites the biological fractionation between the hinge and the main growth axes
appears much less pronounced with, respect to the difference observed in shells from boreal
eutrophic sites. A. cf. excavata from the Mauritanian Shelf are at equilibrium and show depletionfrom equilibrium only in certain increments (years). In this case the increased biologicalfractionation is potentially related to stronger eutrophication following up-welling events.
Radiocarbon-dating (AMS-14C) of fossil A. excavata from the Mediterranean revealed adominance of Last Glacial ages and a few Holocene occurrences. Their stable isotope
composition from time slices between 38 ka and 2 ka cal BP closely match with data obtained
from foraminifera. The wide banding Acesta allows now for a high-resolution sampling andprovides “windows into the past” with an intra-annual resolution.
Contact Information: M. López-Correa, Institut für Paläontologie, Universität Erlangen-Nürnberg, Loewenichstr. 28,
D-91054 Erlangen, Germany, Email: lopez@pal.uni-erlangen.de, Web: www.cool-corals.de72

July 17-21, 2007 z St. Petersburg, Florida USA

Southern Ocean Limpets As Potential High-Resolution Environmental
Archives
Matthias López-Correa1 and M. Taviani2
1
2

IPAL, Institute of Palaeontology, University of Erlangen-Nuremberg, Erlangen, Germany
CNR-ISMAR, Istituto di Scienze Marine, Bologna, Italy

The shell calcite stable isotope composition δ18O and δ13C of gastropod limpets has beenmeasured and tested as potential archive of environmental conditions in the Southern Ocean. We
selected limpets across a wide latitudinal range between 75°S and 52°S. Three limpet species
were analyzed. The ‘Antarctic limpet’ Nacella (Patinigera) concinna is distributed within the
Antarctic Polar Front and was collected from the Antarctic Peninsula, the South Orkneys (Signy
Island) and from South Georgia. North of the Antarctic Polar Front the species Nacella (P.)
magellanica and N. (P.) deaurata were collected from the Falklands and from southern
Patagonian fjords. All three species are highly abundant in rocky intertidal to subtidal habitats,and show a very clear external and internal growth banding. Their oxygen isotope composition isalways at or very close to equilibrium with seawater. The growth rate of the Antarctic limpet N.
(P.) concinna varies between 0.3 and 1.0 cm height-increase per year and is documented to bevery sensitive to environmental factors, including temperature, nutrient availability and icing. Its
seasonal banding offers a broad isotope-sampling interval with good inter- and intra-annual
resolution. Our sampled sites span a wide degree of temperatures and salinity conditions. The
heaviest oxygen isotope values at all sites are at equilibrium with seawater and all three species
reproduce the local conditions very well. Stable isotope measurements in N. (P.) concinna fromthe Antarctic Peninsula show an oxygen isotope range between 2.7 and 4.3 ‰ δ18O V-PDB.
While the ontogenetic transects in the Antarctic Peninsula specimens closely match the annual
temperature amplitude, the limpets from other sites display also a “tail” of depleted oxygenisotope values. The latter monitor the seasonal melt water runoff in the fjords, with higher watertemperatures and strongly lowered salinity. Different species from the same sites show the samerange of oxygen and carbon isotope values. The potential presence of growth-speed dependant“kinetic” vital effect has been tested by two parallel ontogenetic transects along the longest andthe shortest axes in Nacella concinna. Both profiles show the same isotopic variability and amaximum depletion in the fast-grown longest axes of <0.4 ‰ for δ18O.
In thin-sections the different limpet species show extremely fine increments, within the seasonal
banding and promise a high sclerochronological potential on an intra-annual scale. The limpet
lifespan may only be on the order of a few years, but sampling of historical specimens with aknown collection date, will likely provide high-resolution records. These may complement theresolution of historical temperature data-series in remote areas of the Southern Hemisphere.
Furthermore N. (P.) concinna has recently been discovered in many raised Last Glacial beaches
in the Ross Sea as old as 40 ka, and offers the potential for fossil temperature snapshots.
Following this initial screening with manual sampling by a dental drill, we consider these limpets
as suitable target species for high-resolution MicroMill-sampling along ontogenetic transects,
coupled with parallel laser ablation trace-element probing.
Contact Information: M. López-Correa, Institut für Paläontologie, Universität Erlangen-Nürnberg, Loewenichstr. 28,
D-91054 Erlangen, Germany, Email: lopez@pal.uni-erlangen.de, Web: www.cool-corals.de73

First International Sclerochronology Conference

Stable Isotopes (δ18O & δ13C), Trace and Minor Element Compositions ofRecent Lophelia pertusa Deep-Water Corals in the Ionian Sea (Mediterranean
Sea)
Matthias López-Correa1, P. Montagna2, B. Vendrell3, M. McCulloch4 and M. Taviani5
1

IPAL, Institute of Palaeontology, University of Erlangen-Nuremberg, Erlangen, Germany
ICRAM, Rome, Italy
3
Institut de Ciències del Mar (CSIC), Barcelona, Spain
4
ANU-Research School of Earth Sciences, Canberra, Australia
5
CNR-ISMAR, Istituto di Scienze Marine, Bologna, Italy2

The aragonitic skeletons of cold-water corals have a high potential as bathyal in situ archives forpaleoceanography. Therefore, oxygen and stable carbon isotopes (δ18O and δ13C) have been
analyzed, as well as trace and minor element compositions (e.g. Mg/Ca, Sr/Ca, U/Ca, B/Ca &P/Ca) in Lophelia pertusa. This is one of the most important frame-builders, at the Santa Mariadi Leuca (SML) deep-water coral hotspot in the Central Mediterranean. The Apulian Bank isswept by strong currents of the newly formed Adriatic Deep Water Outflow. The temperature of
13.9°C is the highest temperature recorded for L. pertusa and provides thus an important endmember of environmental conditions for our geochemical analyses on living Atlantic andMediterranean cold-water corals. Temperature and salinity (38.77 PSU) are stable throughout theyear and virtually no changes should be observed in the stable oxygen isotope signal - if the coral
would precipitate its skeleton in equilibrium with seawater. We measured various marine
properties, like the seawater oxygen isotope composition (δ18Osw), the stable carbon isotope
composition (δ13C) of dissolved inorganic carbon (DIC), and further parameters like the PO4,
NO3, NO2 and SiO2 concentrations. These geochemical parameters may help to better understandthe geochemistry of the cold-water coral carbonate precipitation and the potential role of L.
pertusa as a phosphate archive. Bottom water at the coral sites shows a mean oxygen isotope
composition of 1.47 ‰ δ18Osw-VSMOW, and δ13CDIC showed a mean of 1.1 ‰ V-PDB. A
section of a living L. pertusa with a thick theca calcification was probed with a Merchantek
MicroMill, which allowed for a high spatial sampling resolution with 10 samples per 1 mm. This
reduced the signal-smoothing inherent to conventional sampling, which averages wider portionsof subsequent increments. The coral-δ18O ranges between -2.0 and +2.8 ‰ V-PDB, and theGaussian data distribution indicates the completeness of the captured isotopic variability,
including heavy equilibrium values. The strict linear correlation of δ13C and δ18O displays the‘kinetic’ vital effect. The intercept of the δ13C/δ18O correlation line with the δ13CDIC-composition
allows to recognize the δ18O equilibrium values of aragonite and to reconstruct watertemperatures despite strong disequilibrium precipitation. Since the environmental parameters (T,S & δ18Osw) are stable, the entire isotopic signal of the coral must be driven by biologicalfractionation. This variability might reflect growth speed variations, potentially related toseasonally varying nutrient availability. Laser ablation tracks show a trace element composition
in dependence from microstructural zones (theca vs. centres of calcification). The parabolic
relation of the classical temperature proxies Mg/Ca and U/Ca point to trace element vital effects,
rendering them unreliable in L. pertusa. The P/Ca-ratio shows similar values as Desmophyllum
dianthus, for which a linear dependence with seawater phosphate (DIP) has been demonstrated(Montagna et al. 2006; Science). Also L. pertusa might thus be a reliable nutrient recorder atbathyal depths.
Contact Information: M. López-Correa, Institut für Paläontologie, Universität Erlangen-Nürnberg, Loewenichstr. 28,
D-91054 Erlangen, Germany, Email: lopez@pal.uni-erlangen.de, Web: www.cool-corals.de74

July 17-21, 2007 z St. Petersburg, Florida USA

Incremental Growth of Fossil Lamnoid Shark Vertebral Centra
Bruce J. MacFadden and Dana J. Ehret
Florida Museum of Natural History, University of Florida, Gainesville, FL

Other than their ubiquitous teeth, shark skeletons are primarily composed of cartilage thattypically does not fossilize. An exception to this rule is the vertebral column, where the centra
grow incrementally and are progressively ossified throughout ontogeny. Incremental growth ofshark vertebral centra are characterized by growth couplets, in which the darker couplet band
represents times of slow growth, whereas the corresponding lighter band represents times of
rapid growth. Although these couplets are generally thought to represent yearly growth, as seen
in other organisms, many factors in extant sharks, e.g., nutritional stress, can confound theseannual cycles. In this study we use stable isotopes of microsamples taken from individual growthcouplets to calibrate seasonal growth in fossil lamnoid sharks. Lamnoids are the clade including
extant great white (Carcharodon carcharias), makos (Isurus), and numerous extinct species
extending back into the late Cretaceous.
We analyzed growth in Otodus obliquus, a 50-million-year-old early Eocene (Ypresian) lamnoid
shark from Morocco. Despite being diagenetically altered, the O. obliquus vertebral centra
preserve a cyclical pattern of isotopes representing seasonal temperature differences. Carbonate
δ18O values archived across the growth axis of three centra from the same individual
systematically varied by about 1.5 per mil, indicating that winter/summer growth couplets arepreserved. Similar to other organisms in which seasonal increments have been analyzed, growth
is most rapid during early ontogeny and slows as the individual matures. The particular
individual of O. otodus analyzed has 19 physical growth bands, which is interpreted to represent
its minimum ontogenetic age.
We also will present results, currently in progress, from an exquisitely preserved great white
shark (C. carcharias), including fossilized jaws and teeth, and associated vertebral column, fromthe late Miocene Pisco Formation of Peru.
Fossil shark centra are rarely found in direct association with the taxonomically diagnostic teeth.
When they do occur together, researchers have a unique opportunity to develop age and growthmodels for extinct sharks, as reported here for the Lamnoidea.
Contact Information: Bruce J. MacFadden, Florida Museum of Natural History, University of Florida, PO Box
117800, Gainesville, FL 32611, Phone: 352-392-1721, ext. 496, Fax: 352-846-0287,
Email: bmacfadd@flmnh.ufl.edu

75

First International Sclerochronology Conference

Cross-dating: A Practical Application to Verify Historical Age Data for
British Columbia Geoduck (Panopea abrupta)
Shayne E. MacLellan, Darlene Gillespie and Judy McArthur
Fisheries and Oceans Canada, Pacific Biological Station, Nanaimo, B.C. Canada

The geoduck (Panopea abrupta) fishery has developed into one of the most valuable fisheries in
B.C. The accuracy of the age data, which is unknown, could have significant impacts on geoduck
assessments. Historically, geoduck shells have been analyzed to estimate age, although thismethod has not been validated for B.C. populations. The historical age data are potentiallysubject to biases associated with a) damaged shells and b) a series of readers over time for which
consistency and accuracy are unknown. In this study we demonstrate the use of tree chronology
techniques to conduct a preliminary review of the accuracy of historical West Coast, B.C. age
data, focusing on biases associated with the use of damaged shells (under-ageing) and reader
drift over time.
Contact Information: Shayne MacLellan, Fish Ageing Lab, Pacific Biological Station, Fisheries and Oceans Canada,
B.C. Canada V9T 6N7, Phone: 250-756-7189 or 250-756-7179; Fax 250-756-7053,
Email: maclellansh@pac.dfo-mpo.gc.ca.

76

July 17-21, 2007 z St. Petersburg, Florida USA

History and Applications of Ageing Living Marine Resources at the Northeast
Fisheries Science Center
Richard S. McBride1, Sandra J. Sutherland1, Jay M. Burnett1 and Nancy E. Kohler2.
12

National Marine Fisheries Service, Northeast Fisheries Science Center, Woods Hole, MA USA
National Marine Fisheries Service, Northeast Fisheries Science Center, Narragansett, RI USA

In the late 1940s, ageing of haddock (Melanogrammus aeglefinus) scales began at what is now
the Northeast Fisheries Science Center (NEFSC). During the past two years (2005-2006),
approximately 100,500 ages were determined for 15 teleost (bony fish), 4 elasmobranch(cartilaginous fish), and 1 bivalve (shellfish) species. These age estimates – based on yearly
increments – are used as part of the process to assess the status of economically-importantfishery populations of the Northwest Atlantic Ocean. This poster reviews the diversity of ageing
methods used at the NEFSC and points out the applications of such data within the framework offishery management in the USA.
No single methodology can be applied to such a broad suite of species. In 2005-2006, otoliths
were the most common hardpart used; they were read whole, baked & broken, or sectioned, toestimate age of 71,600 individuals of 11 teleost species. Fish scales impressed in laminatedplastic were used to age another 25,200 individuals of three teleost species. Baked vertebrae
were used to age an additional 1,100 individuals of one teleost species. Sectioned, stained, orradiographed vertebrae were used to age 500 individuals of three elasmobranch species. Baked,
whole dorsal spines were used to age one other elasmobranch species. Finally, thin sections ofchondrophores were used to age 900 individuals of one bivalve species.
Validation of ageing methodologies at the NEFSC has included: edge analysis, marginalincrement analysis, recapturing tagged fish (including those injected with oxytetracyline), and, in
longer-lived fishes, cross-dating incremental widths, measuring naturally occurring isotopes, orbomb radiocarbon dating. Quality control measures used to evaluate accuracy and precision(repeatability) of ages have included: percent agreement, Chang’s coefficient of variation, agebias plots, age matrix tables, Bowker’s test of symmetry, and reference collections.
The generally high abundances and ‘production ageing’ methods of the economically importantteleost and bivalve species are amenable for using age-structured models for stock assessments.
Many elasmobranchs, on the other hand, are more difficult to collect, and ageing methodologies
are often still experimental. Nonetheless, our improving knowledge of the demographics ofelasmobranchs – typically long-lived, slow-growing, late-reproducing animals with low
fecundity – has been instrumental for the application of ‘rapid assessment’ techniques. These
assessment approaches are used as part of the scientific basis for policy making under the
Magnuson-Stevens Fishery Conservation and Management Act (reauthorized in 2006).
Contact Information: Richard S. McBride, National Marine Fisheries Service, Northeast Fisheries Science Center,
Woods Hole Lab., 166 Water St., Woods Hole MA 02543 USA, Phone: 508-495-2244, Fax: 508-495-2258,
Email: richard.mcbride@noaa.gov

77

First International Sclerochronology Conference

Cod Otoliths…. Indicators of Phenology and Endogeny?
Sophy R. McCully1, R. S. Millner1, G. M. Pilling1, H. Høie2, J. Skadal2 and K. Nedreaas2
1
2

Centre for Environment, Fisheries & Aquaculture Science (Cefas), Lowestoft, Suffolk, EnglandInstitute of Marine Research, Bergen, Norway

Otoliths act as bio-recorders, providing information on the timing of growth in fish. The aim of
this study was to compare phenological differences in timing of the seasonal opaque andtranslucent growth zones between cod (Gadus morhua) otoliths from the southern North Sea andfrom the Barents Sea. These two areas covered a geographic range of approximately 30o in
latitude. Cod from the southern North Sea are exposed to large seasonal temperature cycles,
often with a range of 10oC annually whereas North East Artic (NEA) cod from the Barents Sea
experience differences of only 1-2 oC. In total, 7388 otoliths were analysed from 12 different
years, with the aim of correlating any results to warm and cold episodes in sea temperatures.
Visually the otoliths from the 2 areas differed significantly. The otoliths from the southern North
Sea cod exhibit prominent banding with large translucent zones, and larger opaque zones. The
otoliths from the NEA have less distinct, feint banding patterns, with very small translucent
zones. We found that the 50% transition point from opaque to translucent occurred between June
and July for southern North Sea cod, and 4-5 months later in NEA cod. Comparison with theseasonal pattern of condition in cod suggests that the opaque growth is associated with increased
feeding and condition while the translucent zone represents a period of increasing metabolic
stress. The analysis confirmed that there has been a phenological shift in the timing of growth forthe southern North Sea cod, coinciding with rising temperatures in recent years.
We hypothesise, that the switch from opaque to translucent growth is set by an endogenous
rhythm, in which other influences such as temperature and metabolism behave as modifying notdriving factors. In light of the within-population shifts in the timing of the translucent growth,and the latitudinal differences in the timing of the edge growth, these disparities are discussed inrelation to endogenous rhythms, metabolic stress, and climate change.
Contact Information: Sophy R. McCully, Fisheries Resource Management, Cefas, Pakefield Road, Lowestoft,
Suffolk. NR33 0BY, England, Phone: (+44) 1502 527754, Fax: (+44) 1502 527739,
Email: sophy.mccully@cefas.co.uk

78

July 17-21, 2007 z St. Petersburg, Florida USA

Use of Trace Elemental Fingerprinting to Determine Larval Connectivity inSouthern California Mussel Populations
Lisa A. Levin1, Pat A. McMillan1, Bonnie J. Becker2, Linda Rasmussen1, Kristen Gruenthall1,and F. Joel Fodrie3
1

Integrative Oceanography Division, Scripps Institution of Oceanography, La Jolla, CA, USA
Interdisciplinary Arts and Sciences Department, University of Washington, Tacoma, Tacoma, Washington, USA.
3
Dauphin Island Sea Lab, Dauphin Island, AL USA
2

Using elemental fingerprinting we studied 2 mytilid mussel species, Mytilus californianus, and
M. galloprovincialis in San Diego County in May 2003 and 2005 to determine their connectivity
patterns. We used in situ larval culturing at 13-18 sites, spanning 100 km of shoreline, to createa reference signal of trace elements in the larval shell at these locations. Newly settled juveniles(less than 2mm in size) were then collected 2 weeks after outplanting. The individual larvalshells were analyzed by LA-ICPMS to generate DFA algorithms that describe site and regional
chemical signatures, based largely on Mg, Mn, Cu, Sr, Pb, Ba and Co, ratioed to 48Ca. Using thisregional 'reference map' of chemical signals, we compared the expected larval chemistry for eachregion to the larval shell chemistry of the newly settled juveniles. PCR of the newly settled
juvenile tissue was applied to identify the species. In May 2003, the majority of settling M.
californianus originated in northern San Diego Country, while M. galloprovincialis settlers
exhibited a mix of northern, southern and bay sources. In May 2005, M. californianus settlers
exhibited a greater diversity of origins, while M. galloprovincialis settlers appeared to be fromthe North compared to May 2003. The fingerprinting approach is now being applied toconnectivity of a third mussel, Musculista senhousia, an invasive species. We compared the
mytilid fingerprinting results with larval transport simulations from a numerical model (ROMS)
adapted for the region and time of interest. The outplant/fingerprinting/ modeling approachprovides information about self seeding, species-specific connectivity, and interannual variabilityof great value to marine resource conservation efforts.
Contact Information: Pat A. McMillan, Integrative Oceanography Division, Scripps Institution of Oceanography,
9500 Gilman Dr. 0218, La Jolla, CA 92093-0218, USA, Phone: 858-534-3579, Fax: 858-822-0562,
Email: pmcmillan@ucsd.edu

79First International Sclerochronology Conference

Environmental Controls on Daily Shell Growth of Phacosoma japonicum(Bivalvia: Veneridae) from Japan
Kazushige Tanabe1, Bernd R. Schöne2 and Tsuzumi Miyaji1
12

Department of Earth and Planetary Science, University of Tokyo, Hongo, Tokyo, Japan
Increments Research Group, Department of Paleontology, Institute of Geosciences, University of Mainz,
Mainz, Germany

This study examined the environmental factors controlling daily shell deposition of theintertidal bivalve Phacosoma japonicum from Seto Inland Sea, west Japan and Tokyo Bay,central Japan. Sclerochronological analyses of microgrowth patterns in marked-andrecovered specimens indicate that a pair of two etch-sensitive increments and two etchresistant lines is formed every lunar day. The accretionary pattern of the lunar day growthincrements (LDGIs) reflects tidal cycles. Prominent growth lines were formed during
spring tides when the bivalves were subaerially exposed, and weak ones were deposited
during neap tides when they were continuously submerged. The bivalves stop secretingshell carbonate during winter and early spring. The time interval encompassed by thewinter break in the specimens from Tokyo Bay lengthened as the shells grew older.
Although seawater temperature is the main controlling factor for shell growth, a number ofmutually related environmental factors such as salinity and food availability also affectshell growth. In Tokyo Bay, the broadest LDGIs were deposited between temperatures of
21º and 24 ºC. Our findings provide a basis for the interpretation of the temporal changes inshell microgrowth patterns in terms of environmental conditions of extant and fossil P.
japonicum specimens.
Contact Information: Tsuzumi Miyaji, Department of Earth and Planetary Science, University of Tokyo, 7-3-1
Hongo, Tokyo, 113-0033, Japan, Phone: +81-3-5841-4033, Fax: +81-3-5841-4555,
Email: tsuzumi@eps.s.u-tokyo.ac.jp

80July 17-21, 2007 z St. Petersburg, Florida USA

Micro-scale Elemental Distribution in a Shell of the Venerid Bivalve
Phacosoma japonicum
Kazushige Tanabe1, Yuji Sano2 , Kotaro Shirai2 and Tsuzumi Miyaji1
12

Department of Earth and Planetary Science, University of Tokyo, Tokyo, Japan
Ocean Research Institute, University of Tokyo, Tokyo, Japan

Most bivalves living in the intertidal environment secrete a pair of two broad microgrowthincrements and two narrow microgrowth lines every lunar day (24 hours and 50 minutes).
Combined research of sclerochronology and minor and trace elemental analysis of lunarday growth increments allows us to obtain ultra-high time resolution data of the shell
growth record and its environmental background. Previous authors suggested that Sr/Caand Mg/Ca ratios in coral skeletons can be utilized as proxies of seawater temperatures(e.g., Beck et al., 1992). However, the relationship between these ratios and ambient
seawater temperatures is markedly variable among bivalve shells, (Stecher et al., 1996;
Gillikin et al., 2005); accordingly, no consensus has been reached to use these ratios for(paleo)environmental reconstruction.
In this study, we examined micro-scale elemental distribution patterns in a single specimen of avenerid bivalve Phacosoma japonicum captured alive from the intertidal zone of Tokyo Bay,central Japan, and consider possible factors controlling their temporal variation. After capture, asingle valve of the specimen was sectioned along the maximum shell growth axis, and polishedwith a graded series of carborundum and polishing sheet with fine alumina grains embedded on
the surface. This species secretes lunar-day based shell microgrowth increments (LDGIs) and aclear growth cessation mark in winter, allowing us to mark the exact calendar dates in theinternal microgrowth incremental sequence (Miyaji et al., in press). The ventral margin of thepolished shell surface was observed by means of a Keyence VHX type digital microsope at 200
times and the widths of LDGIs formed in the third annual increment were measured successively
by using an image analyzing software (WinRoof Ver. 2; Mitani Corporation). Subsequently,
micro-scale elemental distribution patterns of Sr, Mg, Mn, Ba, S in the microgrowth increments
were analyzed by means of NanoSIMS and EPMA, and they were compared with theenvironmental data of the nearby seawater during which the shell grew (Aug. 14-28, 2003).
NanoSIMS analysis revealed that Sr/Ca ratio show clear lunar-day based fluctuations, showing
smaller ratios within broader microgrowth increments than narrower microgrowth lines for
Sr/Ca. These lines of evidence were also confirmed by elemental distribution mapping with
EPMA, indicating that the micro-scale fluctuations of Mg, Sr, and Mn are controlled mainly by
the difference of microstructure within LDGIs within the observed seawater temperature range(22.5-27.5ºC). Two peaks showing high Mn/Ca and Ba/Ca ratios were recognized in the LDGI
sequence analyzed, and their relations with salinity and plankton productivity are suggested bycomparison with the environmental data of corresponding dates.
Contact Information: Tsuzumi Miyaji, Department of Earth and Planetary Science, University of Tokyo, 7-3-1
Hongo, Tokyo, 113-0033, Japan, Phone: +81-3-5841-4033, Fax: +81-3-5841-4555,
Email: tsuzumi@eps.s.u-tokyo.ac.jp81First International Sclerochronology Conference

Relationships Between Fish and Otolith Sizes and Impact on Growth Patterns
Kristen M. Munk, Jodi Neil and Rhiannon Jensen
Alaska Department of Fish and Game, Juneau, Alaska, USA

Fish and otolith measurements were compared for 14 North Pacific fish species (sablefish,lingcod, walleye pollock, pacific cod, pacific halibut, 7 rockish spp., sandlance, and pacificherring). Correlation for all measures were positive and high, and somatic length to otolith lengthr2s ranged from 0.576 to 0.969. Good correlation between somatic growth and otolith accretionsuggests that aspects of otolith development – and inherent growth patterns – reflect fish growth
dynamics, and, with correlation similarities across these 7 taxonomic families, possible integrityin otolith accretion properties and subsequent pattern interpretation.
Contact Information: Kristen M. Munk, Alaska Department of Fish and Game, Box 25526, Juneau, Alaska 99802
USA, Phone: (907) 465-3054, Email: kristen_munk@fishgame.state.ak.us

82

July 17-21, 2007 z St. Petersburg, Florida USA

Indian Ocean Dipole Index for the Last 100 Years Recorded in Kenyan Coral
Annual Bands
Hajime Kayanne1, Nobuko Nakamura1, Hiroko Iijima1, Timothy R. McClanahan2, Swadhin
Behera3 and Toshio Yamagata1
1

Department of Earth and Planetary Science, University of Tokyo, Tokyo, Japan
Marine Programs, Wildlife Conservation Society, Bronx, New York, USA
3
Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology,
Yokosuka, Japan
2

Variability in the tropical and subtropical climate in the Indian Ocean has often been explainedin relation to ENSO. However, correlation between ENSO and climate variability is not always
high. Recently, the Indian Ocean Dipole (IOD) was discovered [Saji et al., 1999, Nature, 401,
360-363], which has similar east-west SST and precipitation anomalies and periodicities that are
similar to those of ENSO in the Pacific Ocean. IOD is a seasonally phase-locked interannual
phenomenon, and produces precipitation anomalies in the East African short rains from October
to November. The heavy rains in 1961, 1997 and 2006 were associated with positive IODs inthese years [Yamagata et al., 2004, AGU Geophys. Monogr. Ser., 147, 189-212].
A signature of the IOD in precipitation was detected in the coral core from Malindi, Kenya(3.2°S and 40.1°E). Luminescence intensity under UV light and oxygen isotope values dated at
January, a few months after the short rain period, correlated well with anomalies in precipitation,
and we assigned the oxygen value at January to coral IOD index [Kayanne et al., 2006, Geophys.
Res. Lett., 33, L19709]. To reconstruct IOD events before the instrumental observations, we
extended the coral IOD index record back to 1900 A.D. The coral IOD index marked lightoxygen isotope peaks (corresponding to high short rain precipitation) in 1935, 1952, 1961, 1972,1994 and 1997, and heavy peaks (corresponding to low short rain precipitation) in 1931, 1941,
1953, 1971, 1985, 1991 and 1996. The coral index shows general lightening trend probably
derived from warming, with decadal changes from relatively low amplitude of oscillation in the
1940s and 1980s to large amplitude in the 1930s, 1950s, 1970s and 1990s.
Contact Information: Nobuko Nakamura, University of Tokyo, Hong 7-3-1, Tokyo 113-003 Japan,
Phone: 81358414557, Email: nobunobu@eps.s.u-tokyo.ac.jp83

First International Sclerochronology Conference

Microstructure, Growth Banding and Age Determination of a Primnoid
Gorgonian Skeleton (Octocorallia) from the Late Younger Dryas to Earliest
Holocene of the Bay of Biscay
Sibylle U. Noé1, Lester Lembke-Jene2, Julie Reveillaud3 and Andre Freiwald 1
1

Institute of Paleontology, University of Erlangen-Nuremberg, Erlangen, Germany
Integrated Ocean Drilling Program, Texas A&M University, College Station, TX , USA
3
Renard Centre of Marine Geology and Marine Biology Section, Ghent University, Gent, Belgium
2

A fossil primnoid gorgonian skeleton (Octocorallia) was recovered on the eastern Galician
Massif in the Bay of Biscay (NE Atlantic) from 720 m water depth. The skeleton shows a growthbanding of alternating Mg-calcitic and organic (gorgonin) increments in the inner part,surrounded by a ring of massive fibrous calcite. Three calcite-dominated cycles, bounded bythick organic layers, consist of five light-dark couplets of calcite and gorgonin, as detected inthin sections of the cross-cut skeleton.
Two AMS 14C datings of the fossil skeleton gave ages of 10,880 and 10,820 ± 45 14C years
before present (BP). We arrive at a calibrated age range of 11,829 – 10,072 cal. years BP (twoσ), which comprises the termination of the Younger Dryas to the earliest part of the Holocene.
Stable carbon and oxygen isotopes give evidence to the controls of the internal skeletal structure.
The cyclic calcitic-organic growth banding of the inner skeleton may be controlled by a constantrate of calcite secretion with a fluctuating rate of gorgonin production, possibly related to
productivity cycles in the surface water. The skeletal fabric change of this calcitic-organic
alternation to fibrous calcite forming a massive crust around the skeleton may be the result ofhydrologic changes during the deglaciation with effects on the surface water productivity andparticulate organic matter flux. At reduced rates of organic particle supply and thus of gorgoninproduction, the coral precipitated massive calcite using metabolically generated carbon dioxideand dissolved inorganic carbon from the ambient bottom water. This crust enhanced the skeletal
rigidity, enabling the coral colony to grow in an environment affected by increasing vigour ofcontour currents. Hence, primnoid gorgonians are able to match with varying hydrodynamic
conditions by changing their mode of biomineralisation.
Contact Information: Sibylle U. Noé, Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr.
28, D-91054 Erlangen, Germany, Phone: 49-9131-8524783, Fax: 49-9131-8522690,
Email: noe@pal.uni-erlangen.de84July 17-21, 2007 z St. Petersburg, Florida USA

Varying Growth Rates in Bamboo Corals: Sclerochronology and Radiocarbon
Dating of a Mid-Holocene Deep-Water Gorgonian Skeleton from Chatham
Rise (New Zealand)
Sibylle U. Noé1, Lester Lembke-Jene2, Andre Freiwald1 and Christian Dullo3
1

Institute of Paleontology, University of Erlangen-Nuremberg, Erlangen, Germany
Integrated Ocean Drilling Program, Texas A&M University, College Station, TX , USA
3
Leibniz Institute of Marine Sciences, IFM-GEOMAR, Kiel, Germany
2

Deep-water bamboo corals of the genus Keratoisis (Octocorallia) represent potential highresolution archives of paleoceanographic and climatic variability in deeper water masses andtemperate oceanic realms, owing to their conspicuous growth banding and geochemical tracers intheir skeletons. We studied the sclerochronology and growth rates of a mid-Holocene bamboo
coral skeleton of the genus Keratoisis (Octocorallia) recovered at southwestern Chatham Rise
(New Zealand) from an average water depth of 680 m. The branched internal skeletal axis of thecoral colony shows a vertical alternation of bright Mg-calcitic internodes and dark organic nodes.
The internodes are composed of fibrous crystals surrounded by thin organic seams which areassembled in divergent-radial fascicles and fascicle bundles interfingering in three dimensions.
Unlike the density banding of zooxanthellate scleractinians, the coloured growth banding of
Keratoisis skeletons is produced by varying orientations of fascicle bundles towards the image
plane. Skeletal cross sections of our specimen show three growth interruptions caused bynecrosis of the coral’s coenenchyme, which are recorded by foreign particulate organic matteraccumulation forming distinct dark rings.
Conventional radiocarbon ages decrease from base to top of the trunk and from the central axes
to the margins of the branches, documenting a simultaneous vertical and lateral growth. The
conventional AMS 14C data provided a maximum age of 3975 ± 35 yr BP with a total record of
240 ± 35 yr. This corresponds to a mid-Holocene age. While calculated vertical growth rates
amount to average 5 mm yr-1 during a 55 year record, average radial linear extension rates of 0.4
mm yr-1 are an order of magnitude lower, thus showing an annual resolution of colour bands on amacroscopic scale or a seasonal, weekly and half-weekly resolution on microscopic scales offascicle bundles, individual fascicles and individual crystal generations respectively. The nodesconsisting of 1 µm thick collagen-like gorgonin laminae even allow for a daily resolution.
Concentric incremental accretion around the central axis in the early growth stages changed intoa unilaterally asymmetric growth during late-stage evolution, probably triggered by theestablishment of a stable unidirectional current system with reduced nutrient flux at the side ofcondensed growth. While colour band counts, related to the conventional AMS 14C ages,
document an annual accretion of macroscopic growth bands in the inner concentric and complete
outer parts of the skeleton, incremental growth rates at the condensed side are distinctly reduced.
Hence, this specimen proves that growth rates of bamboo corals may vary within individual
skeletons, showing implications on paleoceanographic reconstructions around Chatham Rise bymeans of stable δ13C and δ18O isotopes.
Contact Information: Sibylle U. Noé, Institute of Paleontology, University of Erlangen-Nuremberg, Loewenichstr.
28, D-91054 Erlangen, Germany, Phone: 49-9131-8524783, Fax: 49-9131-8522690,
Email: noe@pal.uni-erlangen.de85

First International Sclerochronology Conference

Sclerochronology in Massive Corals: Advantages and Disadvantages
Kristine DeLong and Timothee Ourbak
College of Marine Science, University of South Florida, St Petersburg, FL USA

In the studies of paleoclimatology and paleoceanography, one of the advantages of using massive
corals as a proxy recorder, compared to sediment cores, is the ability to assign a (sclero)chronology by counting the growth bands visible on X-Radiographs. The high- and low-density
bands have been shown to grow annually by using radioactivity and dye staining [Knutson et al.,
1972; Barnes and Lough 1996]. Furthermore, massive coral skeletal material contains a myriadof geochemical proxies (δ18O, δ13C, Sr/Ca, Mg/Ca, U/Ca, Ba/Ca, among others), which makes
massive corals a perfect tool for reconstructing tropical paleoclimate.
We will first introduce the different growth bands included in the coral skeleton, from sub daily
to seasonal. We will also show the potential errors that could happen when building a coralsclerochronology from a single core by using a 525-year (7 meter high) massive Porites from thetropical Pacific as case study. We will show how chronology errors compounded over time could
potential influence the frequency analysis, a classical exercise in paleoreconstruction, andpotentially mask real signals present in the record. Massive corals are very useful for paleo
reconstruction studies compared to other proxy records; however, there are limitations incounting annual density bands in a single massive coral record where the compoundedchronology error could potentially bias the data analysis.
Contact Information: Timothee Ourbak College of Marine Science, University of South Florida, 140 7th Avenue
South, St Petersburg FL 33701, USA, Phone: 727-553-1538, Fax: 727-553-1189, Email: tourbak@marine.usf.edu

86July 17-21, 2007 z St. Petersburg, Florida USA

Sclerochronology Study of Ruditapes philippinarum Shell
Y. M. Paulet1, C. Poulain1, C. Paillard1, E. Morize2 and H. De Pontual2
1
2

LEMAR CNRS UMR 6539, IUEM, Technopole Brest Iroise, Plouzané, France
LASAA, Ifremer, Plouzane, FranceWith the goal to use the shell of the Manila clam, Ruditapes philippinarum, to reconstruct passed
environmental conditions, we have investigated the periodicity of its microstructural layer
deposits. Such knowledge is of prerequisite importance to finally use carbonate shells as highfrequency proxies of the environment where they lived through geochemical analysis.
R. Philippinarum lives from mediolittoral to near subtidal zones, buried in some centimetres ofsandy to muddy sediments. The studied animals were collected in subtidal position in the estuaryof the Auray river (Brittany, France). As only annual growth ridges may be observed externally,
photonic and electronic microscopic investigations were carried out on shell thin transverse
sections with the aim to detect internal microstriae. Some shells were submitted to calcein
marking, and reseeded quickly in their original environment. Clams sampled at the same place
were processed for δ18O measurements along the growth axis (micromill, IRMS). Winter marks
caused by reduced growth in winter were visible both on the shell surfaces (external ridges) andon the transversal sections. Micro-increments were easily identified in the prismatic layer of thinsections (50 µm thickness). Using winter marks as time basis, nearly 350 increments has beencounted during the third year of life (between winter 2 and winter 3). This observation completed
by striae counting on calcein marked clams allowed us to propose the existence of a daily
rhythmicity in shell increment deposition in manila clams. Moreover, our results suggest thatwinter growth stop is of very short duration, or doesn’t exist in this species.
This result, new for this species, allowed us to place oxygen stable isotopic variation measured in
the same shells onto a calendar scale. Salinity effect on oxygen isotopic incorporation in the shell
can therefore be quantified by analysing discrepancies between shell δ18O and seawatertemperature continuously recorded at the sampling site.
Contact Information: C. Poulain, LEMAR CNRS UMR 6539, IUEM, Technopole Brest Iroise, Place Nicolas
Copernic, 29280 Plouzané, France, Phone: +33-2-98498838, Fax: +33-2-98498645,
Email: celine.poulain@univ-brest.fr

87

First International Sclerochronology Conference

Constructing Growth Chronologies from Long-lived Bivalves: Have We Got it
Right?
C. A. Richardson, N. M. Fraser, P. Butler and J. D. Scourse
School of Ocean Sciences, College of Natural Sciences, University of Wales Bangor, Menai Bridge,
Anglesey, UK

Shells of the long-lived bivalve Arctica islandica contain incremental growth series which havebeen used in the construction of growth increment chronologies from shells collected fromvarious coastal and open ocean locations and from museum collections worldwide. Different
approaches have been adopted to extract the information from the shells and to measure,construct and analyse the incremental series. For example some chronologies have been
constructed using growth increment series measured along the outer margin of the right or leftshell valves while others use series measured in the hinge tooth region at the shell umbo. There isas yet no objective methodology for identifying “annual” growth lines in these two regions anddistinguishing them from growth lines of “non-annual” origin. Nor has any attempt been made tostandardise the methodologies so that a common approach can be adopted similar to that used bydendrochronologists. This is important because the incremental growth series enable the archived
environmental information contained in the shells to be annually resolved, significantly
enhancing their value as high resolution recorders of long-term environmental changes rightacross range of the species. The accurate matching of chronological years with growth lines, andthe consistency of interpretation across research groups are therefore key aspects of the future
development of the field of sclerochronology.
In this paper we describe an objective methodology for the routine identification andmeasurement of growth lines within the hinge tooth of A. islandica. We recommend that thismethodology be adopted to enable robust comparisons and inter-regional cross-matching to beundertaken between growth increment chronologies from widely separated sites. We use datafrom A. islandica shells from the Fladen ground, northern North Sea, UK to compare
incremental growth series from shells collected in the same trawls, from different trawls in thesame area and across spatial scales of up to 60km to establish the level of coherence between thegrowth series
Contact Information: Dr Chris Richardson, School of Ocean Sciences, College of Natural Sciences, University ofWales Bangor, Menai Bridge, Anglesey, LL59 5AB, Phone:+44-1248-382855, Fax:+44-1248-716367,
Email:c.a.richardson@bangor.ac.uk

88July 17-21, 2007 z St. Petersburg, Florida USA

Daily Microgrowth Bands in Bivalve Shells; Where is the Evidence?
C. A. Richardson
School of Ocean Sciences, College of Natural Sciences, University of Wales Bangor, Menai Bridge,
Anglesey, UK

Early research claimed that sectioned cockle and clam shells contain microgrowth bands with anapparent daily periodicity and that the surface striae of scallop shells were produced under thecontrol of a daily rhythm.
In this paper evidence is presented from the shells of marked bivalves held under controlledlaboratory conditions of illumination, seawater temperature and food supply and from field
deployments. The research reveals that cockle Cerastoderma edule, clam Tapes philippinarum
and mussel Mytilus edulis shells held in semi-diurnal tidal situations deposit growth bands during
tidal emersion and growth increments during immersion. When these bivalves are held undercontinuously immersed conditions for similar periods they deposit weak growth bands with aperiodicity related to the rate of shell deposition and not to a daily periodicity i.e. shells growing
slowly deposit fewer bands than fast growing bivalves. Scallops Pecten maximus held undercontrolled laboratory conditions and in field deployments produce surface striae whose
formation is controlled by the rate of shell growth (extension) and is independent of a daily
periodicity. Scallops growing slowly deposit fewer striae than fast-growing individuals held
under the same conditions for similar periods of time.
The findings from this research and the possible mechanisms involved in the formation of
microgrowth banding and striae formation are discussed in the light of recent reports of theoccurrence of daily striae production in pectinids and the interpretation of banding with anapparent daily periodicity in the long-lived clam Arctica islandica and the hydrothermal ventmussel Bathymodiolus sp.
Contact Information: Dr Chris Richardson, School of Ocean Sciences, College of Natural Sciences, University ofWales Bangor, Menai Bridge, Anglesey, LL59 5AB, Phone:+44-1248-382855, Fax:+44-1248-716367,
Email:c.a.richardson@bangor.ac.uk

89

First International Sclerochronology Conference

Gastropod Statoliths: a Tool for Reconstructing the Growth of Gastropods
C. A. Richardson, E. Chatzinikolaou and C. Saurel
School of Ocean Sciences, College of Natural Sciences, University of Wales Bangor, Menai Bridge,
Anglesey, UK

Many gastropod species possesses a pair of statocysts, each containing a single statolith of
calcium carbonate floating in endolympth, and are the sense organs for equilibration providing
the mollusc with information on the direction of gravity with reference to the animal’s position.
The statoliths are located in the foot tissue between the cerebropleural and pedal ganglia.
Observations of extracted whole and sectioned statoliths reveal the presence of a series ofalternating narrow dark rings separated by wider translucent increments in statoliths of up to
250µm diameter. In the netted whelk Nassarius reticulatus, formation of the first ring occurs atlarval settlement and subsequent rings are deposited annually. The wider light increments formin the spring (between March and June) when seawater temperatures are increasing, whereas thedarker narrow rings are deposited between the late summer and winter (August to February). The
relationship between statolith diameter and shell length for larval, juvenile and adult netted
whelks N. reticulatus (0.3-31 mm) is: Statolith diameter (µm) = 36.31· Shell length (mm)0.464.
Substitution of length in this equation allows the age of the whelk to be estimated. Validation of
the periodicity of the rings in statoliths of four Red whelks Neptunea antiqua was established bycomparing the number of statolith rings with the number of seasonal Mg:Ca ratio cycles present
in shell calcium carbonate samples drilled sequentially from along the growth axis. There wasexact correspondence between the number of growth rings and the number of element ratio
cycles in two shells and a 1-year difference in the estimated age between the two methods in theother two shells, evidence which is strongly indicative of an annual periodicity of deposition to
the statolith rings. Shell lengths estimated from the diameters of the prominent statolith rings innecklace shells Polinices pulchellus and those obtained from length frequency data analysis(LFDA), were broadly congruent strongly suggesting an annual periodicity to the statolith rings.
In this paper we report on experiments and field collections which were conducted to ascertain
the periodicity of ring formation in the statoliths of larval, juvenile and adult netted whelks
Nassarius reticulatus, in adult red whelks Neptunea antiquata and necklace shells Polinices
pulchellus to validate their use as a tool for estimating the age of these gastropods.
Contact Information: Dr Chris Richardson, School of Ocean Sciences, College of Natural Sciences, University ofWales Bangor, Menai Bridge, Anglesey, LL59 5AB, Phone:+44-1248-382855, Fax:+44-1248-716367,
Email:c.a.richardson@bangor.ac.uk

90July 17-21, 2007 z St. Petersburg, Florida USA

Seawater Temperature Reconstruction from Annual Growth Increments in
the Shell of Pliocene Arctica islandica from the Coralline Crag (UK)
A. Finlayson1, E.M. Harper1 and C. A. Richardson2
12

Department of Earth Sciences, University of Cambridge
School of Ocean Sciences, College of Natural Sciences, University of Wales, Bangor, Menai Bridge, Anglesey,
UK

Annually resolved growth lines in Recent shells of the long-lived bivalve Arctica islandica havebeen shown to have great potential for the study of the effects of environmental change on
annual growth rates and the study of stable oxygen isotopes have shells have allowed for thereconstruction of water temperatures. The occurrence of fossil A. islandica in the Pliocene
shallow marine Coralline Crag of eastern England, offers an opportunity for the study ofseasonal growth rates and the reconstruction of seawater temperatures during the ‘mid Pliocene
warm period’ of the late Holocene. Examination of the microstructure and mineralogy of the
Crag A. islandica, using scanning electron microscopy and cathodoluminesence, showed them tobe well preserved with no evidence of diagenesis. Measurement of the growth increments
showed rapid growth rates in all individuals, higher than those recorded for modern individuals
by Witbaard et al. (1997). The largest clams attained an age >160 years and this longevity issimilar to those of live- caught clams from the North Sea and Atlantic Ocean. Analysis of18
O/16O ratios in shell material samples drilled from between and across adjacent growthincrements showed clear seasonality of growth line deposition during the lowest seawatertemperatures. Reconstruction of the seawater temperatures from the oxygen isotopes at the timeof shell deposition suggest an annual temperature range of between 3.6 and 12.8°C, notsignificantly dissimilar from those recorded in the present North Sea (5 to 14°C).
Contact Information: Dr Chris Richardson, School of Ocean Sciences, College of Natural Sciences, University ofWales Bangor, Menai Bridge, Anglesey, LL59 5AB, Phone:+44-1248-382855, Fax:+44-1248-716367,
Email:c.a.richardson@bangor.ac.uk

91

First International Sclerochronology Conference

Historical and Geographic Trends in the δ15N Sewage Signal Encoded in
Florida and Bahamas Gorgonians
Owen A. Sherwood 1, Brian E. Lapointe 2, Michael J. Risk 3 and Robyn Jamieson 4
1

Department of Biology, Memorial University, Newfoundland, Canada
Harbor Branch Oceanographic Institute, Florida, USA
3
School of Geography and Earth Sciences, McMaster University, Ontario, Canada
4
Department of Earth Sciences, Memorial University, Newfoundland, Canada
2

Stable nitrogen isotope (δ15N) analysis has proven an effective “fingerprint” of sewage
contamination in coral reef environments. To assess the extent of sewage contamination off
eastern Florida, we measured δ15N in reef gorgonians. Samples were collected from near-shore
reefs at an affected site in Broward County, Florida (population 1.78 million) and a control site at
Green Turtle Cay, Abacos, Bahamas (pop. 450). The most recently-grown skeleton (branch tips)
averaged 7.7 ± 1.4 ‰ (1 sd, n = 11) at Broward County, and 2.0 ± 0.7 ‰ (n = 11) at Green
Turtle Cay. Based on δ15N signatures of anthropogenic and natural nitrogen inputs measured ateach site, sewage (δ15N ~ 9 ‰) is the source of higher δ15N at Broward County. To assess
historical trends in sewage contamination, sections were cut from the bases of gorgonians andgrowth rings were isolated for δ15N analysis. Based on the number of growth rings, the time-span
represented by each coral ranged from 30-60 years. At Broward county, δ15N increased by anaverage of 2.0 ± 0.8 ‰ (n = 7) over the lifetime of the corals, paralleling population growth in
the county. At Green Turtle Cay, δ15N decreased by an average of -0.3 ± 0.1 ‰ (n = 7), despite
modest increase in the local population. The most likely cause for the observed decline is theincreasing influence of atmospheric nitrogen deposition in the airshed to the west.
Concentrations of rainfall NOx (δ15N = - 3.0 ‰) and NH4 (δ15N = +1.0 ‰) have increased 3-foldon Florida's east coast since monitoring began in the 1970s and now account for ~ 20 % of thereef N budget at Green Turtle Cay. Because Florida is strongly influenced by anthropogenic
atmospheric emissions, the δ15N records in Broward County likely underestimate the extent of
the sewage problem. Overall, our results confirm the substantial and growing body of evidence
that eutrophication is the principal cause for the shift from coral- to macroalgal-dominance oncoral reefs in Florida.
Contact Information: Michael J. Risk, School of Geography and Earth Sciences, McMaster University, 1280 Main
St West, Hamilton, ON, Canada, L8S 4K1. Phone: 519-369-3874. Email: riskmj@mcmaster.ca

92July 17-21, 2007 z St. Petersburg, Florida USA

Changes in Gape Frequency and Thermal Tolerance in the Freshwater
Bivalves Anodonta cygnea and Margaritifera falcata
David L. Rodland1, Bernd R. Schöne2, Sven Baier2, Zengjie Zhang2, Wolfgang Dreyer3 andNicolas A. Page 4
1

Department of Biological Sciences, George Washington University, Washington DC, USA
Institute for Geology, Johannes Gutenberg-University, Mainz, Germany
3
Zoological Museum, University of Kiel, Kiel, Germany
4
Raincoast Applied Ecology, Vancouver BC, Canada
2

Physiologically driven rhythms in bivalve mollusks are predicted to vary as a function of
metabolic rate and temperature, in contrast to genetically predisposed biological clocks. This canbe evaluated using long-term video observation techniques under controlled environmental
conditions in laboratory aquaria. The freshwater bivalves Anodonta cygnea and Margaritifera
falcata were used in order to evaluate the effect of temperature on rhythms in gape and siphon
activity. The frequency and duration of shell closure vary with temperature in both species,
although differing responses are observed. Valve closure frequency and duration increases in
Anodonta cygnea with temperature, with a dramatic rise in frequency and cumulative duration
above 31° C. By contrast, valve closure and frequency peak at approximately 25° C in
Margaritifera falcata, but spontaneous valve closure ceases above 29.5° C. The mean durationof individual closures decreases continuously as temperature rises in both species, consistent
with limitation of closure interval by increased oxygen demand. Indications of physiologicalstress are consistent with sclerochronologically calibrated stable isotope studies in bivalve
mollusks and other invertebrates, which indicate shutdown of shell growth at temperatures above
31° C. These results provide insight into the thermal tolerance of these species and to changes inphysiological activity as this threshold is approached.
Contact Information: David L. Rodland, Department of Biological Sciences (Geological Sciences Program), The
George Washington University, Bell 101C, 2029 G St. NW, Washington DC 20052 USA, Phone: (202) 994-1008,
Email: rodland@gwu.edu

93

First International Sclerochronology Conference

Seasonality in the North Sea during Selected Climate Transitions(Allerod and Late Medieval Climate Optimum) – Bivalve Sclerochronology(Arctica islandica)
Bernd R. Schöne1 and Jens Fiebig2
1
2

Geosciences, University of Mainz, Mainz, Germany
Geosciences, University of Frankfurt, Frankfurt, Germany

Seasonal temperature patterns may have changed through time in response to current global
warming. However, the temporal resolution of available proxy records is not sufficient toquantify paleotemperature seasonality prior to anthropogenic forcing of the climate. In thepresent study, we reconstructed seasonal and inter-annual temperature patterns of the North Sea
during the last 140 years, the Allerod Interglacial and the Late Medieval Climate Optimum using
sclerochronological and oxygen isotope data from bivalve shells. On average, the climate during1278-1353 AD was ca. 1.1°C colder and seasonality was ca. 60% less than today. During theAllerod, long-term temperatures remained about 3.2°C below present values, and absolute
summer and winter anomalies were ca. -4°C and -2.7°C, respectively. However, seasonality wasstatistically indistinguishable from today. Long-term average temperatures compare well withexisting data for the Late Medieval and Allerod, but detailed information on seasonality during
the studied time intervals has never been presented before. Our study indicated that individual
bivalve shells can open discrete, near-century long, ultra-high-resolution windows into theclimate past. Such information can be vital for testing and verifying numerical climate models.
Contact Information: Bernd R. Schöne, Department of Applied & Analytical Paleontology & INCREMENTS,
Institute of Geosciences, University of Mainz, Becherweg 21, 55128 Mainz, Germany, Phone: +49 6131 39 24757,
Fax: +49 6131 39 24768, Email: schoeneb@uni-mainz.de

94July 17-21, 2007 z St. Petersburg, Florida USA

Environmental Controls on a Unique Siderastrea Coral Morphology
Jennifer L. Sliko and Gregory Herbert
Geology Department, University of South Florida, Tampa, FL USA

The Pliocene-Pleistocene boundary is climatically dynamic, punctuated by the closure of theIsthmus of Panama, the start of Walker Circulation (and end of the permanent Pliocene El Nino
event in the Pacific), and a regional extinction event in the Gulf of Mexico. Climate has been
linked to this extinction event, however, the relationship is not certain, and there is considerable
debate as to how the environment changed. An important advance in this debate is simply
defining average climate conditions before and after the extinction event to assess how theenvironment changed over time.
One important clue as to how the environment changed comes from the unusual morphology offossil stacked-mushroom shaped Siderastrea corals, which were present in Florida only before
the extinction event. These corals exhibit cyclical cessations of growth and recovery events, andthe end result is something like a stack of limestone mushroom heads, with new growth
spreading laterally in a dome shape over the underlying dead layer. This dome shape is indicativeof medium to high sedimentation rates (based on field examinations from the Dry Tortugas).
We will use isotopic and trace element analysis to reveal that the growth breaks in the stackedmushroom shaped corals are related to seasonal changes in environmental patterns, such as
nutrient levels, temperature, and sediment load. Most importantly, the Siderastrea corals provide
a critical test of the main hypotheses proposed thus far for the extinction, all of which involvesome kind of changes in oceanographic upwelling (nutrients), glacial extent (temperature), andEl Nino intensity (in Florida, precipitation and runoff of terrestrial sediments). These corals
provide a detailed record of environmental change in the subtropical, nearshore marine
environment of the western Gulf of Mexico during a time of global climate change.
Contact Information: Jennifer Sliko, Department of Geology, University of South Florida, 4202 E. Fowler Ave.
SCA 528, Tampa, FL 33612, USA, Email: Jsliko@cas.usf.edu

95

First International Sclerochronology Conference

Estimating Growth Rates of Loggerhead Sea Turtles (Caretta caretta) using
Skeletal Growth Marks
Melissa L. Snover1, Larisa Avens2 and Aleta A. Hohn2
1
2

NOAA/NMFS/Pacific Islands Fisheries Science Center, Honolulu, HI, USA
NOAA/NMFS/Beaufort Lab, Beaufort, NC, USA

Growth rates in and among sea turtles are highly variable, and gaining an understanding of thisvariability is difficult using traditional means, such as mark-recapture. Skeletochronology is apromising technique for the rapid assessment of individual growth rates in sea turtles, but
appropriate methodologies must be developed before meaningful conclusions can be drawn.
Here, we present an analysis of the relationship between humerus dimension and somatic
growth, demonstrating that it is allometric, with a higher slope for small pelagic turtles and alower slope for larger benthic turtles. The use of this relationship to accurately back-calculate
carapace lengths from diameters of skeletal growth marks was validated with 12 loggerheads thatwere captured, tagged, released, and subsequently recovered as dead strandings. We estimatedthe length at capture by back-calculating, using the diameter of the skeletal growth mark mostrepresentative of the time of capture. The mean difference between the measured carapace length
at capture and our estimate of carapace length obtained through back-calculation was 1.0 cm ±0.3 S.E. In terms of annual growth rates, our mean error was 0.2 cm/yr ± 0.1 S.E. We
demonstrate that, with proper application, back-calculation in combination withskeletochronology can be a powerful tool in studying the growth dynamics of individual sea
turtles.
Contact Information: Melissa L. Snover, NOAA/NMFS/Pacific Islands Fisheries Science Center, 2570 Dole Street,
Honolulu, HI 96822 USA, Phone: 808-983-5372, Fax: 808-983-2902, Email: Melissa.Snover@noaa.gov

96July 17-21, 2007 z St. Petersburg, Florida USA

Isotope Sclerochronology and Season of Annual Growth Line Formation of
the Limpet Patella vulgata from Spain and Norway
Donna Surge and J. Walter Gurley
University of North Carolina, Department of Geological Sciences, Chapel Hill, NC, USA

Mollusc shells can serve as biological archives because of their accretionary growth habit. Thesebio-archives preserve ecological and environmental information at subdaily to annual timescales. Periodic growth lines and increments mark intervals of time relating to internal(reproduction) and external (temperature, salinity, food availability, tides, etc.) factors.
Temperature is the dominant control on annual and seasonal growth line and increment
formation for most molluscan species. The timing of annual and seasonal growth line formation
can vary along a latitudinal, and hence, temperature gradient. This pattern has been observed in
Mercenaria mercenaria and M. campechiensis shells along the east coast of the United Statesusing oxygen isotope ratios (δ18O) as a proxy for temperature1. Mercenaria shells from coastal
New England form dark increments reflecting slowed growth during winter months, whereas
Mercenaria from the southeastern coast form dark increments during summer months. The
transition between winter and summer dark increment formation occurs at the boundary between
the warm- and cold-temperate biogeographic provinces. Does this pattern exist in the eastern
North Atlantic?
Previous sclerochronologic and isotopic investigation of the European limpet, Patella vulgata,collected near Newcastle, England, identified annual growth lines that formed during winter2.
The most positive δ18O values marked the winter season and the location of annual growth lines.
Do annual growth lines form during winter across the entire geographic range of this species? P.
vulgata occurs from Spain to Norway. This range includes the warm- and cold-temperatebiogeographic provinces. The boundary between the two lies near the western entrance to theEnglish Channel3. One shell from the Lofoten Islands, Norway, was provided by the Smithsonian
Institution (Museum #25549), and one was collected alive from Cantabria, Spain. Like the
Newcastle shells, prominent growth lines in the Norway shell occurred at the most positive δ18O
values, indicating formation during winter. In contrast, prominent growth lines in the Spain shelloccurred at the most negative δ18O values, coinciding with summer. Future work will examine
specimens collected near Brest, France and Plymouth, England to test whether the transition
between winter and summer growth line formation occurs at the boundary between the warmand cold-temperate biogeographic provinces as it does in the western North Atlantic.
Notes:
1

Jones, D. S. & Quitmyer, I. R. Marking time with bivalve shells: oxygen isotopes and season of annual increment
formation. Palaios 11, 340-346 (1996).

2Fenger, T., Surge, D., Schöne, B. R. & Milner, N. Sclerochronology and geochemical variation in limpet shells(Patella vulgata): A new tool to reconstruct Holocene coastal sea surface temperature. Geochemistry Geophysics
Geosystems (accepted pending revision).

3

Briggs, J. C. Global Biogeography (Elsevier, New York, 1995).

Contact Information: Donna Surge, University of North Carolina, Department of Geological Sciences, CB #3315,
Mitchell Hall, Chapel Hill, NC 27278 USA, Phone: 919-843-1994, Fax: 919-966-4519, Email: donna64@unc.edu

97First International Sclerochronology Conference

In Situ Growth Experiment of a Deep-sea Cold Seep Mollusk Using a New
Growth Chamber with Fluorochrome Calcein
Kazushige Tanabe1, H. Kitazato2, K. Fujikura3, K. Oguri2 and Yohei Tada1
1

Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Hongo,
Bunkyo-Ku, Tokyo, Japan
2
Research Program for Paleoenvironment, Institute for Research on Earth Evolution, Japan Agency for MarineEarth Science and Technology, Natsushima-Cho, Yokosuka-City, Kanagawa, Japan
3
Marine Biology and Ecology Research Program, Extremobiosphere Research Center, Japan Agency for MarineEarth Science and Technology, Natsushima-Cho, Yokosuka-City, Kanagawa, JapanA new method of in situ chemical marking experiment was developed and applied to a deep sea
cold seep giant clam Calyptogena, and the shell growth rate of this clam in its natural habitat wasdetermined. Calcium bonding fluorochrome calcein was used for vital staining of a living clam
kept in a specially designed in situ growth chamber that was set on the sea bottom of off
Hatsushima Island, in the western part of Sagami Bay, central Japan. As a result of thisexperiment, a part of the shell margin of the living clam was stained forming a thin fluorescentband. The clam was recovered 12 days after vital staining, and its shell growth rate wasdetermined by observing internal shell microgrowth increments between the fluorescent bandand the shell margin. The observed shell growth rate of this specimen is much slower than thereported values of C. kilmeri at the other cold seep site (Monterey Bay) and C. magnifica at thehydrothermal vent site (the Galapagos Rift). This method is useful for sclerochronological age
and growth rate determinations of many other bathal and bathyal marine organisms with amarginal-growing skeleton.
Contact Information: Yohei Tada, Department of Earth and Planetary Science, Graduate School of Science, The
University of Tokyo/7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033 Japan, Phone: +81-3-5841-4031,
Fax: +81-3-5841-8791, Email: ytada@eps.s.u-tokyo. ac.jp98July 17-21, 2007 z St. Petersburg, Florida USA

Iron and Zinc in Mytilus edulis Shells Reflect Improved Water Quality in
Boston Harbor, MassachusettsRenee K. Takesue1, Michael H. Bothner2 and Alan E. Koenig3
1

U.S. Geological Survey Coastal & Marine Geology Team, Santa Cruz, CA, USA
U.S. Geological Survey Coastal & Marine Geology Team, Woods Hole, MA, USA
3
U.S. Geological Survey Minerals Resources Team, Denver, CO, USA
2

Water quality in Boston Harbor, Massachusetts, has significantly improved since September
2000. At this time the discharge point for 350 million gallons per day of treated sewage effluent
was moved from the harbor mouth to a location 15 km offshore. We measured trace metals in
subtidal Mytilus edulis shells harvested near the former harbor outfall to explore whether bivalve
shell chemistry recorded the shift in water quality over the past six years.
M. edulis shells were collected live on December 15, 2006 and immediately shucked. Trace
metals and minor elements were measured in the outer calcite layers of four shells using a solidstate 193 nm laser ablation system (New Wave Technologies) coupled to a Perkin Elmer Elan
Dynamic Reaction Cell-II quadrupole inductively-coupled plasma mass spectrometer (ICP-MS)
at the U.S. Geological Survey (USGS) laser ablation ICP-MS lab in Denver, Colorado.
Elemental concentrations in shells were calculated relative to USGS carbonate referencematerials MACS-1 and a prototype carbonate reference material. Shell chronologies wereinferred from cyclical magnesium to calcium (Mg/Ca) variations. Lowest Mg/Ca values roughly
corresponded to external growth rings, suggesting annual periodicity. Mg/Ca cycles decreased inwidth and amplitude as the mussels aged. Three of the shells were over 8 years old. Interestingly,
sodium to calcium (Na/Ca) values varied cyclically with a 2-fold higher range and generallysmoother peaks than Mg/Ca values. The controls on Na incorporation in the shell were different
from those on Mg because Na and Mg peaks were out of phase. We do not as yet know themechanism influencing Na variations in M. edulis shells.
In two of the M. edulis shells, iron (Fe) concentrations were up to 1250 ppm and 2000 ppm inshell material deposited prior to September 2000, compared to less than 50 ppm after September
2000. Fe peaks were sharp and occurred over time scales of days to weeks, suggesting episodic
uptake of Fe-rich water and/or Fe-rich particles by the mussels. Zinc (Zn) closely followed Fe
before September 2000 but was not enriched to the same degree. Copper (Cu) and Lead (Pb)were not significantly elevated in the shells. We are examining both direct and indirect linkages
between the lower metal levels in the post 2000 shell material and the diversion of the sewage
effluent. Estimates of dissolved Fe and Zn in the effluent are approximately 100 ug/l and 23 ug/l,
respectively, about an order of magnitude higher than in harbor water. The abrupt decrease in the
exposure of Boston Harbor mussels to sewage effluent in 2000 may explain the observed
decrease in shell metals. An indirect influence of the outfall relocation is that harbor sediments
are becoming more oxygenated as a result of markedly reduced nutrient and organic carbon
loading from sewage. Such chemical changes might reduce the fluxes of dissolved metals fromanoxic sediments beneath the sediment-water interface.
Contact Information: Renee Takesue, USGS, 400 Natural Bridges Drive, Santa Cruz, CA 95060, USA,
Phone: 831-427-4794, Fax: 831-427-4748, Email: rtakesue@usgs.gov

99

First International Sclerochronology Conference

Mid-Pliocene Environments in the Eastern U.S. Gulf Coast: A Study of Stable
Isotopes and Growth Increments in the Gastropod Conus adversarius
Kai Tao and Ethan L. Grossman
Department of Geology and Geophysics, Texas A & M University, College Station, Texas, USA

The middle Pliocene (3.5-2.5 Ma) is considered to be the last global warm period in the Earthhistory. This global warming may not be evenly distributed due to oceanographic and latitudedifferences. Early studies based on general circulation modeling and stable isotopes suggest the
low latitude middle Pliocene seawater temperature is equal to or slightly higher than modern seasurface temperatures (SSTs). However, new models and alkenone-derived paleotemperature
disagree with that contention. We examine this discrepancy by analyzing oxygen isotopes in a
Conus adversarius specimen collected from the Pinecrest Beds in Florida. Shells were seriallysampled at 5 mm intervals along the spire, providing monthly resolution. Data for the shell werecompared with determinations of growth increments using gray-scale measurements ofphotomicrographs of the spire.
Results to date for a five-year-old Conus adversarius indicate the middle Pliocene shallow
seawater temperatures (18-29 ºC) are similar to modern SST (16-31 ºC), but with less seasonalchange, which is accordant with the early studies. Oxygen isotope profiles yield an asymmetricalpattern, suggesting faster growth in spring and summer and slower growth in winter. Growth
rates decrease with ontogeny. Growth increments were compared with the δ18O-derived timeseries. These sub-monthly increments show no relationship between band thickness and growthrate. Additional tests will be conducted on shells selected for their prominent banding.
Contact Information: Kai Tao, Department of Geology and Geophysics, Mail Stop 3115, Texas A & M University,
College Station, TX 77840, USA, Phone: 979-458-4486, Email: taokai@tamu.edu

100July 17-21, 2007 z St. Petersburg, Florida USA

Episodic Variability in Elemental Concentrations as a Potential Aging Tool in
Deep-Water Gorgonians (Keratoisis spp): Comparisons with Radiometric andMorphological Age Estimators
Ronald E. Thresher1, Jess Adkins2, Colin MacRae3 and Nick Wilson3
1

CSIRO Marine and Atmospheric Research and Wealth from Oceans Flagship Program
California Institute of Technology
3
Microbeam Laboratory, CSIRO Minerals
2

Deep-water corals in general, and high magnesium calcite gorgonians in particular, have recently
become of considerable interest as potential paleo-recorders of deep-ocean conditions. For thisapplication, however, it is critical that age and growth variability be determined accurately andprecisely. Several aging methods have been applied to these gorgonians, including three
radiometric methods (U/Th, Pb/Ra and 14C) and enumeration of putative annual growthincrements, both visual and as determined by SEM. Early in our analyses of specimens of the
deep-water gorgonian genus Keratoisis, we considered the potential of enumerating periodic
banding in elements along radial growth axes of the coral as an aging tool, on the basis ofapparent annual cycles in water temperature at depth and likely effects of temperature on growthin general and incorporation of Mg into the calcite in particular. This interest was re-sparked by arecent report (Roark, et al., 2005, GLR 32, L04606) suggesting that ages in Northern PacificKeratoisis spp. could be determined by counting quasi-regular peaks in Sr/Ca ratios along thecoral’s radius.
We examined data quality and regularity in element banding in specimens of southern PacificKeratoisis and the closely related genus Lepidisis, using quantitative line analyses and semiquantitative mapping of Mg, Sr, S and Ca using electron probe microanalysis. Banding isconspicuous in some elements (e.g., Mg), but the annual nature of the banding is less clear-cut.
Counts across a coral based on element maps tend to suggest ages consistently less than thoseindicated by other methods, such as radiometric aging. As well, counting the element bands
becomes somewhat subjective as bands differ widely in intensity (= element weight-fraction) andin inter-band spacing and tend to fuse and split at relatively short distances around the coral.
Spectral analysis of the higher quality quantitative data suggest a weak periodicity of Mg/Ca
ratios in Lepidisis that are consistent with age estimates made from counts of visual increments
assumed to be annual, but do not match radiometric age estimates. In Keratoisis, apparent annual
periodicity of element weight-fractions is weak, but there are stronger peaks that appear to reflect
4-5 year and ca. 11-year cycles. The former may indicate EN-SO-related variability in growth orwater temperature, whereas the roughly 11-year periodicity is consistent with persistent reportsof quasi-decadal variability in marine and terrestrial systems in the Australian region. These
longer time-scale signals could be used as routine, relatively accurate and precise aging tools, but
require an assumption of their long-term stability in the environment.
Contact Information: Ron Thresher, CSIRO Marine Laboratory, GPO Box 1538, Hobart 7001 Australia,
Phone: 61-3-62325378, Fax: 61-3-62325485, Email: Ron.Thresher@csiro.au101

First International Sclerochronology Conference

Intra-bone Oxygen Isotope Seasonality Patterns - A Promising New Approach
for Vertebrate Skeletochronology?
Thomas Tütken1, Claire Rollion-Bard2 and Martin Sander3
1

Department for Analytical and Applied Paleontology, University of Mainz, Mainz, Germany
Centre de Recherches Pétrographiques et Géochimiques, Vandoeuvre-lès-Nancy, France
3
Institute for Paleontology, University of Bonn, Bonn, Germany
2

Skeletochronology is a method for age and growth rate determination for extant and extinct
vertebrates that is based on annually formed histological growth marks in skeletal tissues such aslines of arrested growth (LAGs). LAGs represent time markers of osteogenesis when bone
deposition was periodically interrupted. LAGs are a common feature in skeletal tissues of many
extant and extinct vertebrate species regardless of size, tissue type, metabolic rate or
phylogenetic position. Although they occur mostly in ectothermic reptiles and amphibians, theyalso occur in endothermic birds and mammals as well as in many dinosaurs.
In most cases LAGs form due to seasonal environmental influences such as variations intemperature, humidity, periodicity of sunlight, and the availability of dietary and water resources,
and are thus annual in origin. However, also intrinsic genetic, hormonal and/or physiologicalfactors (e.g. oogenesis, hibernation) or non-annual and non-cyclical events (e.g. illness,
starvation, droughts) might also result in the formation of a LAG. In fast-growing bone ofendothermic vertebrates and certain dinosaurs (e.g. sauropods), LAGs are often absent. If
present, LAGs are routinely used as annual time markers for the determination of ontogenetic
age and growth rates of extinct vertebrates. To enable ontogenetic age estimates and growth rate
determinations for vertebrates that do not form LAGs, other time markers are needed.
The oxygen isotope composition of bone apatite might be such a skeletochronologic marker.
Accretionary growing, non-remodelled bone tissue should register a multi-year proxy record ofingested meteoric water oxygen isotope composition. The oxygen isotope composition of
meteoric water displays a temperature-dependent seasonal cyclicity which is potentially recorded
as a time series of intra-bone oxygen isotope composition. Such seasonal oxygen isotope cycles
could be used as an annual time marker and thus for isotope skeletochronology.
To test this hypothesis, modern bones of a crocodile (Alligator mississippiensis) and an ostrich(Struthio camelus) of known ontogenetic age were studied for their bone histology, and seriallysampled to get high-resolution oxygen isotope time series over the period of their ontogenetic
growth. Serial microsampling of bone growth increments was performed with two different
analytical techniques and spatial resolutions: (1) Bone powder samples were taken with a
Merchantek Micromill from polished long bone slices and analysed for their oxygen isotope
composition after chemical pre-treatment, and (2) in situ oxygen isotope measurements were
performed on polished bone thin sections with a CAMECA IMS 1270 ionprobe. Implications of
the oxygen isotope results for skeletochronology, formation of LAGs and determination of
ontogenetic ages and growth rates of vertebrates will be discussed.
Contact Information: Thomas Tütken, Department for Analytical and Applied Paleontology, University of Mainz,
Joachim-Becher-Weg 21, Mainz, D-55099, Germany, Phone: +49-6131-39 22387, Fax: +49-6131-39 24768,
Email: tuetken@uni-mainz.de102

July 17-21, 2007 z St. Petersburg, Florida USA

Statistical and Spectral Analysis of Growth Increments in Freshwater
Mussels, Switzerland
Eric P. Verrecchia and Séverine Vancolen
Geodynamics of the Biosphere Laboratory, Institute of Geology and Hydrogeology, University of Neuchâtel,Switzerland

The present research uses a biostatistical approach to assess the influence of the environment on
the growth of two species of bivalve Unionidae, Unio tumidus and Anodonta anatina, from Lake
Neuchâtel, Switzerland.
With simple Euclidian morphological measurements, it is possible to show that the growth
pattern of these two species is different in terms of size, shape, and rate of growth. On the other
hand, a morphological approach demonstrates the perfect symmetry of the two different valves(right and left) of both species.
The main aim of this work is to study the growth pattern using thin sections from Unio tumidus
shells. These thin sections have been observed using a Scanning Electron Microscope (SEM).
Prisms related to growth increments have been identified and measured from the ventral marginof the shell, corresponding to a growth period of approximately 2 years. The measurements
obtained resulted in signals built with the successive prism width. Wavelets and Fourier analyses
have been applied to the signals in order to detect different periods in shell growth, assuming thatone prism represents one day.
In addition, shells have been scanned using a 3D scanning system in order to map the topographyof the shell surface. Images obtained have been also studied using wavelets and Fourier analyses
in order to find possible growth patterns.
Preliminary results using these methods show that the environment introduces cyclicity duringshell growth. It has been demonstrated in many papers that the influence of the moon is recorded
in marine shells because of tides. Our results emphasize the same type of influence on freshwaterbivalves despite the absence of noticeable terrestrial tides.
Contact Information: S. Vancolen, Institute of Geology and Hydrogeology, Rue Emile-Argand 11, Case postale 158,
2009 Neuchâtel, Switzerland, Phone: 0041 (0) 32 718 26 30, Email: severine.vancolen@unine.ch103

First International Sclerochronology Conference

The Chemistry of Freshwater Mussels as a Proxy for Late Holocene River
Conditions in the Netherlands
Emma A. A. Versteegh1, Simon R. Troelstra1 and Hubert B. Vonhof2
1
2

Department of Palaeoclimatology and Geomorphology, VU University, Amsterdam, the Netherlands
Department of Sedimentology, VU University, Amsterdam, the Netherlands

The rivers Rhine, Meuse and their branches are the major river systems in the Netherlands. Bothrivers can cause damaging flood events in a large part of their catchment areas. Such events
happened in the 1990s and may become more frequent as discharges have increased over the last
100 years due to increased precipitation. Each river has its own characteristic seasonal oxygenisotope pattern reflecting rain water and melt water input.
Freshwater mussels of the genus Unio are large bivalves that are widely distributed in the
Netherlands. They can reach a size up to 10 cm long with an age of approximately 15 years.
Shell aragonite is precipitated in clearly visible seasonal growth bands. As characteristics ofwater chemistry are fixed in these growth bands, freshwater mussels serve as an archive for pastwater compositions. Traditionally much sclerochronological research has been done on marine
bivalves using δ18O as a proxy for temperature and/or salinity. Recently the scope has broadened
to freshwater bivalves initially using growth increment widths as an environmental proxy, butalso using δ18O as a proxy for water source or discharge.
In the light of climate change, flood events are likely to become more frequent. Insight in pastriver conditions and flood frequencies is crucial to predict impacts of future climate change. The
project (BSIK; Climate Changes Spatial Planning) aims at the reconstruction of late Holocene
discharge patterns of the Rhine and Meuse rivers through stable isotope and trace element
analyses on growth increments of freshwater mussels.
The project consists of a monitoring experiment with living freshwater mussels in both rivers,
the calibration of the method with a 20th century collection of shells and the reconstruction oflate Holocene river conditions with shells from archaeological finds. Results of the extensive
stable isotope work on these collections will be presented here.
Also the preliminary results of a novel technique to unionid research will be presented namely
high resolution Laser Ablation ICP-MS records of trace elements on shells from all three timeslices.
Contact Information: Emma A. A. Versteegh, Department of Palaeoclimatology and Geomorphology, Faculty ofEarth and Life Sciences, VU University, De Boelelaan 1085, 1081 HV Amsterdam, the Netherlands,
Phone: +31 (0) 20 598 94 20, Fax: +31 (0) 20 598 99 41, Email: emma.versteegh@falw.vu.nl

104

July 17-21, 2007 z St. Petersburg, Florida USA

The Seasonal Timing of Annual Growth Increments in the Shells of theBivalve Arctica islandica (ocean quahog): A Circum North Atlantic
Perspective using Oxygen Isotopes
Alan D. Wanamaker Jr.1,3, Karl J. Kreutz1, Douglas S. Introne1, Bernd R. Schöne2,
Chris Richardson3, James Scourse3 and Harold W. Borns1
1

Climate Change Institute and Department of Earth Sciences, University of Maine, Orono, Maine, USA
Increments Research Group, Department of Paleontology, Institute of Geosciences, University of Mainz, JohannJoachim-Becher-Weg 21, Mainz, Germany
3
School of Ocean Sciences, University of Wales, Bangor, Menai Bridge, Isle of Anglesey, Wales, United
Kingdom2

We investigated the seasonal timing of annual growth increments in seven shells of the longlived bivalve Arctica islandica using oxygen isotopes. The shells used in this study were
sampled (by us and others) using high-resolution isotope milling procedures from locations
around the North Atlantic (Western Gulf of Maine, Nantucket Shoals, Iceland, Southern North
Sea). Further, shells collected from the Gulf of Maine included a 142-year-old modern shell(collected alive in 2004), and three fossil A. islandica shells (corrected 14CAMS = 1030 ± 78 AD;
1320 ± 45 AD; 1357 ± 40 AD), thus an assessment of temporal changes in the formation ofannual growth increments during the late Holocene was possible from this location. Evidence
from oxygen isotopes from each location generally showed that annual growth increments wereformed when water temperatures were warmest (during early autumn). We found little evidence
from shells sampled from the Gulf of Maine that indicated a substantial change in the seasonaltiming of annual growth increments during the late Holocene. These results will help constrain
intra-annual shell-derived chronologies over a large geographic area in the North Atlantic, andimprove sub-annual oceanographic reconstructions using this bivalve.
Contact Information: Alan D. Wanamaker Jr., School of Ocean Sciences, Room 301-Westbury Mount, University ofWales, Bangor, Menai Bridge, Isle of Anglesey, Wales, LL59 5 AB, United Kingdom, Phone: 01248 382853(International: 44 1248 382853), Ext: 2853, Fax: 01248 716367 (International: +44 1248 716367),
Email: alan.wanamaker@umit.maine.edu

105

First International Sclerochronology Conference

Extracting Paleoenvironmental and Paleoclimate Information from
Mercenaria campechiensis Shells Dating to the Vandal Minimum, Coastal
Southwest Florida, USA
Ting Wang1, Donna Surge1, and Karen Jo Walker2
1
2

Department of Geological Sciences, University of North Carolina, Chapel Hill, NC, USA
Florida Museum of Natural History, University of Florida, Gainesville, FL, USA

Four climate episodes, initially recognized in European historical and proxy archives, mark thelater part of the Late Holocene: the Roman Warm Period (RWP), Vandal Minimum (VM),
Medieval Warm Period (MWP), and Little Ice Age (LIA). Are there differences in timing,
character, and magnitude of these climate episodes elsewhere on the globe? Oxygen isotope(δ18O) variation in shells has long been used as a proxy for paleoenvironmental and paleoclimatechange. Here, we take advantage of these biological archives that have accumulated inarchaeological shell deposits associated with the Calusa Indians of coastal southwest Florida.
The Calusa inhabited the region of Charlotte Harbor and Pine Island Sound, and one of theirprincipal towns was located at Pineland on Pine Island. Pineland was occupied from AD 50 toca. 1710, but was punctuated by short periods of abandonment.. Therefore, Pineland's middens
and mounds potentially contain a rich archive of paleoenvironmental/paleoclimate variation
preserved in shells that are found within these deposits. Use of archaeological Mercenaria
campechiensis shells and Ariopsis felis otoliths from Pineland in the study of the RWP and LIAintervals has been successful in a previous study. Shells of the southern quahog, M.
campechiensis, dating to the VM (AD 500-800) are the focus of the present study. Based on
stratigraphic and zooarchaeological information, we hypothesize that the VM was the coldest
climate episode in southwest Florida over the last two millennia, more severe than the better
known LIA. Moreover, sea-level records for the eastern Gulf of Mexico show a regression forthe sixth through eighth centuries. Both the zooarchaeological evidence and sea-level records
suggest lowered salinity during this time. To test our hypothesis, three shells from the VM wereanalyzed isotopically: one shell dates to AD 700-800, and two shells date to AD 550-600. δ18O
values ranged from -3.40 to +1.97‰, -2.07 to +0.35‰, and -1.62 to +0.71‰, respectively.
Modern, RWP, and LIA shells have δ18O values that are higher than the VM shells: modern: 2.40 to +2.10‰; RWP: -1.28 to +1.53‰; LIA: -2.16 to +1.19‰. These data suggest that the
freshwater wedge in the estuary would have been shifted gulfward during the VM. This
explanation is consistent with the stratigraphic and zooarchaeological data and sea-level records.
However, to fully support our conclusion, we will examine δ18O values from otolith pairs – a
successful approach based on our previous research.
Contact Information: Ting Wang, University of North Carolina, Department of Geological Sciences, CB #3315,
Mitchell Hall, Chapel Hill, NC 27599, Email: twang@email.unc.edu

106July 17-21, 2007 z St. Petersburg, Florida USA

Diary of a Bluegill: Daily d13C and d18O Records in Otoliths by Ion
Microprobe
B. C. Weidel1, T. Ushikubo2, S. R. Carpenter1, N. T Kita2, J. J. Cole3, J. F. Kitchell1, M. L. Pace3
and J. W. Valley2
1

Center for Limnology, University of Wisconsin, Madison, WI
Department of Geology and Geophysics, University of Wisconsin, Madison, WI
3
Institute for Ecosystem Studies, Millbrook, NY
2

The concentric layers of calcium carbonate within fish otoliths record daily growth rates inindividual fish and are increasingly used as chemical recorders of a fish’s environment. Stable
isotope ratios from the otolith can be used to create a history of the environmental conditions,such as temperature, experienced by a fish throughout its lifetime. Current analytical capabilities
have limited the level of spatial/temporal resolution and the size of otolith that can be examined.
We used an ion microprobe to obtain high spatial resolution and high precision d13C and d18O
data within the daily ring structure of freshwater fish otolith. Ion microprobe pit sizes of 1015µm diameter, corresponding to 1-9 days, across a sectioned otolith radius, produced a hightemporal time series of d13C and d18O for 5 years of fish growth. d18O precision was adequate toestimate temperature to ~1°C. A whole-lake 13C addition indicated that otolith d13C responds
immediately to changes in d13C of carbon sources and that otolith d13C was influenced equallyby the d13C of diet and water. The ability to “read” an environmental history from the chemicalcomposition of individual daily growth bands in otoliths from any species of fish has thepotential to be a powerful tool for fisheries science.
Contact Information: Brian C. Weidel, Center for Limnology, University of Wisconsin – Madison, 680 N. Park St.
Madison, WI 53706, phone (607)227-3109, email: weidel@wisc.edu

107First International Sclerochronology Conference

Growth Patterns in the Littoral Mollusk Donax variabilis
Kelley S. Whatley and C. Fred T. Andrus
Department of Geological Sciences, University of Alabama, Tuscaloosa, AL, USA

The aragonite shell of the mollusk Donax variabilis has been established by several studies as a
useful proxy in the reconstruction of sea surface temperature variation. However the presence ofgrowth increments as a result of temperature or other environmental oscillations has not been as
intensively studied for this species. This project examines the occurrence of growth incrementsin the shells of Donax variabilis. Thin sections of the shell are analyzed by microscope after
immersion in Mutvei’s solution, an etching blue dye comprised of a mixture of Alcian blue,
acetic acid, and gluteraldehyde. This solution is used to draw out the alternating light and darkbanded growth increments in the shell, if these bands are present.
The specimens used in this study were collected along the Gulf of Mexico beaches of Alabama.
Donax variabilis lives only in the swash zone in waters near open ocean salinities, and has a life
span of approximately one year. Therefore, the oxygen isotope ratio of the water in which thespecies resides is within a narrow range of values. This comparatively small range of oxygenisotope values in its habitat contributes to the usefulness of the species as a proxy in sea surface
temperature reconstruction, as estimations of water isotope content must be made when applying
oxygen isotope thermometry.
Since Donax variabilis is a short-lived species and filter-feeds in the swash zone, moving in andout with waves and tides, it is hypothesized that sub-weekly (possibly daily or tidal) growthincrements may be observed in the growth history of the shell. If so, this mollusk species may be
a useful proxy for reconstructing extremely high resolution sea surface temperature variation.
In our research, oxygen isotope curves will be established for the shells by taking samples with amicromill at close intervals along the shells’ ontogeny. Increments observed in the shells will becompared to these curves in order to establish the relationship between oxygen isotope content,
temperature, and any detected shell increments.
Contact Information: Kelley S. Whatley, Department of Geological Sciences, University of Alabama, 202 Bevill,Box 870338, Tuscaloosa, AL 35401, USA, Phone: 205-534-0853, Fax: 205-348-0818,
Email: whatl011@bama.ua.edu

108

July 17-21, 2007 z St. Petersburg, Florida USA

Growth Patterns and Storm Surge Effects in the Estuarine Mollusk Rangia
cuneata
K. Rhett Chambers, C. Fred T. Andrus and Kelley S. WhatleyDepartment of Geological Sciences, University of Alabama, Tuscaloosa, AL, USA

The bivalve Rangia cuneata (often called rangia) is a common inhabitant of the upper reaches ofbrackish water estuaries along the Northern Coast of the Gulf of Mexico. Rangia have a lifespanof approximately 4-5 years depending on the water temperature and other factors, including
salinity, which they tolerate between 0-19 parts per thousand (ppt), though the clams prefers
salinity levels between 5-15 ppt. During laboratory experiments, rangia do not endure prolonged
exposure to open air, thus seem to be exclusively sub-tidal. The substrates in which R. cuneata
prefers to live include sand, mud, and sub-surface vegetation. It is not a selective feeder and is
known to collect contaminants at a relatively high rate.
Rangia’s role in an ecosystem includes acting as a link between the primary estuary producers
and secondary consumers. The secondary consumers which prey on and consume R. cuneata
include crustaceans, fish, fowl, and mollusks. The black drum (Pogonias cromis) and sheepshead(Archosargus probatocephalus) are the two most common fish predators. All of these biologicaland environmental factors create changeable and dynamic habitat conditions that likely affectincremental growth patterns. No published data exist regarding incremental growth in thisspecies, and data concerning other upper estuary species are few. Highly dynamic environments
such as the Mobile Bay estuary, Alabama, USA may yield insight into fundamental issues
pertinent to growth patterns in a wide range of aquatic organisms.
R. cuneata are common in the upper Mobile Bay estuary including an area in the northernreaches, proximal to the river delta. Live specimens were collected in this area in Summer 2006
and Fall 2006. The outer surface of some of the collected shells exhibit 1 or 2 deep notches thatappear to be growth breaks. These notches are possibly indicative of a disruptive event over the
past 4-5 years, which has caused a change in the incremental growth of the specimens. These
disruptive events could be tropical storm surges such as occurred during Hurricane Ivan in 2004
and Hurricane Katrina in 2006, which both hit the central Gulf Coast and Mobile Bay region.
Incremental growth bands in the Mobile Rangia cuneata specimens will be examined todetermine if the notches on the shell surface are signatures of such storm events. Oxygenisotopes ratios will be measured to constrain the water temperatures and salinities in which theclams grew. Oxygen isotope fractionation will be assessed through comparisons to in situ
temperature measurements taken by automatic data logger. These comparisons will facilitate
determination of the causes of regular incremental growth in addition to the possible storm surge
impacts.
Contact Information: Kelley S. Whatley, Department of Geological Sciences, University of Alabama, 202 Bevill,Box 870338, Tuscaloosa, AL 35401, USA, Phone: 205-534-0853, Fax: 205-348-0818,
Email: whatl011@bama.ua.edu

109

First International Sclerochronology Conference

How Continuous Is the Data Recorder in Mollusk Shells? A Case Study ofChione Cancellata from Florida Bay
G. L. Wingard, J. B. Murray and R. Stamm
U.S. Geological Survey, Reston, VA, USA

As part of the U.S. Geological Survey’s effort in the Greater Everglades Ecosystem Restoration,a study was initiated to determine the utility of sclerochronology in deriving information aboutpast environments of Florida Bay and Biscayne Bay. To develop goals and targets forrestoration, resource managers need detailed information on seasonal, annual and decadalchanges in the estuaries. Specifically, the project objectives were to develop a high resolution
methodology to analyze variability in shell chemistry as a proxy for past salinity, water quality,
and sources of freshwater. In order to accomplish these objectives, we needed to assess theaccuracy and completeness of the information recorded in shell layers. The research questions
were: 1) What are the spatial and temporal patterns of growth? 2) Is growth a response toenvironmental factors such as salinity or temperature? 3) Do variations in shell chemistry
accurately reflect changes in the water column, or are they strictly vital effects?
We focused our experiments and analyses on Chione cancellata (Veneridae). Chione wasselected as the test organism for several reasons: 1) thick, ornamented shell facilitates
measurement; 2) widely distributed and locally abundant in Florida Bay; 3) tolerant of a wide
range of salinities; 4) field evidence suggests it is relatively long lived (3-7 years); and 5) a large
body of sclerochronologic work has been done on Mercenaria, another Veneridae clam. Growthstudies were conducted on Chione cancellata to determine the relationship between the timing ofshell growth and chemical variations in the shells themselves. Two habitats were set up in
Whipray Basin in February 2001 near the water monitoring station, which records waterchemistry and meteorological data, and 200 specimens were collected locally, labeled, digitallyphotographed, and placed in the habitats. The habitats were checked on a regular winter/summer
schedule every year, with occasional spring and fall collections, through December 2003.
Salinity and temperature experiments, using specimens collected in the field, were set up in alaboratory setting to test mortality under varying environmental conditions in order to determine
if specimens are capable of recording critical events.
Preliminary results show that 40-47% of the population retrieved in the summer showed growth,
while only 1-12% of the population retrieved in the fall or winter showed growth. Therefore,
some seasonality exists in the growth patterns, but exceptions do occur, and year roundinformation is not being recorded. Larger/older individuals showed limited growth during any
season, so adults do not act as reliable data recorders. Although Chione have a wide range oftolerance to salinity changes, they do die when salinity and temperature go outside of their“comfort zone”, therefore, they are not functioning as data recorders during extreme events. The
answer to whether shell analyses will be useful for restoration of south Florida’s estuaries is –maybe. Although they are not recording complete information, selective use of juveniles to lookat summer salinity patterns is valid especially if combined with statistical treatment of the data.
Contact Information: G. Lynn Wingard, U.S. Geological Survey, MS 926A National Center, Reston, VA 20192.
Phone: 703-648-5352, Fax: 703-648-6953, Email: lwingard@usgs.gov

110July 17-21, 2007 z St. Petersburg, Florida USA

Shell Architecture and Stable Isotope Signature of a Giant Deep-Sea Oyster(Azores Archipelago)
Max Wisshak1, Matthias López Correa1, Joachim Jakobsen2 and André Freiwald1
1
2

Institute of Palaeontology, Erlangen University, Erlangen, Germany
Rebikoff-Niggeler Foundation, Horta, Azores, Portugal

Along the steep slope of the Azores Archipelago, large numbers of enigmatic giant deep-sea
oysters were documented alive and recovered with the aid of a submersible in close to 500 m
water depth in the southern Faial Channel. They belong to a yet undescribed species of
Neopycnodonte and are known from the Mediterranean (mainly fossil) and few E-Atlantic
occurrences, with the Azores record representing the westernmost occurrence to date.
These up to several dozen centimetre sized bivalves thrive in particularly high densities under
overhangs where their cemented left valves are growing in many generations on top of eachother, leading to stacked aggregates resembling a pile of dishes. This strategy is interpreted as ameasure to enhance shell stability and allowing for a comparatively rapid growth to size at a low
overall shell thickness before consecutively thickening with little increase in diameter.
Cross-sections of resin-embedded valves reveal a complex architecture featuring prominent
growth increments. Mainly three different shell microstructure types are developed as there are(i) the dense cross-foliated ligostracum and dorsal endostracum containing empty lenticularvoids, (ii) a very porous ventral endostracum composed of cross-foliated laminae alternatingwith thick vesicular layers, and (iii) a dense prismatic myostracum. Two orders of growthincrements can be recognised in the former two microstructure types, with prominent growthintervals of ca. 0.5 to 1 mm in thickness being composed of numerous faint second orderintervals.
Close to the hinge of both valves and following specific growth increments in the ligostracum, ahigh-resolution (~one sample every 100 µm) stable isotope analysis (δ18O and δ13C) was carriedout in order to reveal growth rhythms and to evaluate the suitability of these potentially longliving organisms as palaeoenvironmental archive.
Contact Information: Max Wisshak, Institute of Palaeontology, Erlangen University, Loewenichstr. 28, 91054
Erlangen, Germany, Phone: +49-9131-8524784, Email: wisshak@pal.uni-erlangen.de111

First International Sclerochronology Conference112July 17-21, 2007 z St. Petersburg, Florida USA

Author Index
Bold numbers indicate presenting authors.
Abe, Osamu ............................................................. 52
Abe, Shuhei ............................................................. 59
Adkins, Jess ........................................................... 101
Alexander, Ricky..................................................... 14
Ambrose, Jr., William G.................................... 16, 44
Andersson, Carin ..................................................... 30
Andrus, C. Fred T...................................... 3, 108, 109
Arkhipkin, Alexander I.............................................. 4
Arnold, William S. .................................................... 5
Avens, Larisa........................................................... 96
Baier, Sven .............................................................. 93
Balson, Peter............................................................ 56
Bardeau, J. F............................................................ 57
Becker, Bonnie J...................................................... 79
Behera, Swadhin...................................................... 83
Bird, Annemarie ...................................................... 56
Bisling, Peter ............................................................. 6
Black, Bryan A. ......................................................... 7
Blewett, Tina ........................................................... 29
Boehlert, George W................................................... 7
Booth, Amanda.......................................................... 8
Borns, Harold W.................................................... 105
Bothner, Michael H. ................................................ 99
Brey, Thomas ............................................................ 9
Brickle, Paul ............................................................ 10
Buhl, D. ............................................................. 46, 48
Buick, Devin P. ................................................... 9, 53
Burchell, Meghan .............................................. 11, 63
Burnett, Jay M. ........................................................ 77
Buster, Noreen A..................................................... 50
Butler, Paul G. ................................................... 12, 88
Cabioch, G............................................................... 68
Cannon, Aubrey........................................... 11, 62, 63
Carilli, Jessica E. ............................................... 13, 33
Carmichael, Ruth H. ................................................ 14
Carpenter, S. R. ..................................................... 107
Carricart-Ganivet, Juan P. ....................................... 15
Carroll, Michael L. ............................................ 16, 44
Carroll, Monica ................................................. 17, 18
Cerrato, Robert M.............................................. 19, 20
Chambers, K. Rhett ............................................... 109
Chanona-Espinosa, Laura........................................ 15
Chatzinikolaou, E. .................................................. 90
Chessel, Anatole ...................................................... 26
Clarke, Leon J.................................................... 27, 71
Clough, Lisa ............................................................ 16

Cole, J. J. ............................................................... 107
Cuif, J.-P.................................................................. 69
Cuif, Jean-Pierre...................................................... 40
Dando, P. R. ............................................................ 71
Dauphin, Yannicke .................................................. 40
Daverat, Françoise................................................... 25
de Pontual, Hélène....................................... 25, 57, 87
de Rafelis, Marc ...................................................... 67
DeLong, Kristine L............................................ 21, 86
Dennis, P. F. ............................................................ 42
Dodge, R. E. ............................................................ 43
Dreyer, Wolfgang.................................................... 93
Dufour, Elise ........................................................... 38
Dullo, Christian ....................................................... 85
Dunca, Elena ........................................................... 22
Edgerly, Jessica ...................................................... 16
Ehret, Dana J. .................................................... 23, 75
Elliot, M. ................................................................. 68
Emmanuel, Laurent ........................................... 24, 67
Fablet, Ronan............................................... 25, 26, 57
Fernandez, Ernesto ............................................ 37, 41
Fiebig, Jens.............................................................. 94
Finlayson, A. ........................................................... 91
Fodrie, F. Joel.......................................................... 79
Folkvord, Arild........................................................ 30
Fraser, N. M............................................................. 88
Freitas, Pedro........................................................... 27
Freiwald, Andre................................... 72, 84, 85, 111
Fujikura, K............................................................... 98
Galimberti, Mariagrazia .......................................... 28
Gao, Yongwen......................................................... 29
Geary, Dana H......................................................... 49
Geffen, Audrey J. .............................................. 30, 31
Gibson-Reinemer, Daniel ........................................ 65
Gillespie, Darlene .............................................. 32, 76
Godfrey, Jessie M.................................................... 33
Goewert, Ann .......................................................... 34
Goodwin, David H............................................. 35, 36
Gosselin, Marc................................................... 37, 38
Greenacre, Michael.................................................. 16
Griesshaber, E. ....................................................... 47
Gröcke, Darren R. ....................................... 11, 62, 63
Grossman, Ethan L. ......................................... 39, 100
Gruenthall, Kristen .................................................. 79
Grumet, Nancy ....................................................... 13
Gurley, J. Walter ..................................................... 97

113

First International Sclerochronology Conference

Guzmán, Nury........................................38, 40, 41, 69
Harper, E.M. ............................................................91
Harwood, Andrew J. P.............................................42
Hattenrath, Theresa..................................................14
Hattersley, Michael..................................................10
Heaton, Tim .............................................................56
Helmle, K. P. ...........................................................43
Henkes, Gregory A. .................................................44
Henry, Kelly M........................................................45
Herbert, Gregory......................................................95
Hickson, Jon ............................................................56
Hidalgo, José Manuel ..............................................31
Hippler, Dorothee ........................................46, 47, 48
Hoffmann, Erik N. ...................................................49
Hohn, Aleta A..........................................................96
Hoie, Hans ...................................................30, 31, 78
Holmes, Charles W..................................................50
Hop, Haakon............................................................44
Hufthammer, Anne Karin ........................................30
Hughen, Konrad.......................................................13
Huntley, J. W. ..........................................................51
Huyghe, Damien ......................................................24
Iijima, Hiroko ..............................................52, 59, 83
Immenhauser, A...........................................46, 47, 48
Introne, Douglas S. ................................................105
Ivany, Linda C. ..............................................9, 53, 54
Jakobsen, Joachim .................................................111
Jamieson, Robyn......................................................92
Jensen, Rhiannon .....................................................82
Johnson, Andrew L. A. ......................................55, 56
Johnson, Beverly J. ..................................................44
Jolivet, A..................................................................57
Jones, Douglas S..................................................8, 58
Kassner, Jeffrey .......................................................20
Kaufman, D. S. ........................................................51
Kayanne, Hajime .........................................52, 59, 83
Kennedy, Hilary.................................................27, 71
Khim, Boo-Keun................................................60, 61
Kikuchi, Ruy K. P....................................................70
Kim, Jin Kyung........................................................61
Kingston, Andrew W. ........................................62, 63
Kita, Noriko T..................................................49, 107
Kitazato, H...............................................................98
Kitchell, J. F...........................................................107
Koenig, Alan E. ...........................................64, 65, 99
Kohler., Nancy E. ....................................................77
Kossak, Ute..............................................................66
Kowalewski, M........................................................51
Krause, Jr., R. A.......................................................51
Kreutz, Karl J.........................................................105

114

Kulakowski, Edward................................................22
Laetz, Cathy A. ........................................................19
Lapointe, Brian E.....................................................92
Lartaud, Franck..................................................24, 67
Lazareth, Claire E. ...........................37, 38, 40, 68, 69
Leão, Zelinda M. A. N.............................................70
LeCornec, F. ............................................................68
Lee, Carol E. ............................................................49
Lembke-Jene, Lester..........................................84, 85
Lentini, Carlos A. D.................................................70
Levin, Lisa A. ..........................................................79
Libertinova, J. ..........................................................71
Liqourish, Mark N. ..................................................55
López-Correa, Matthias .......................72, 73, 74, 111
MacFadden, Bruce J. ...............................................75
MacLellan, Shayne E.........................................32, 76
MacRae, Colin .......................................................101
Marca, A. D. ............................................................42
McArthur, Judy..................................................32, 76
McBride, Richard S. ................................................77
McClanahan, Timothy R..........................................83
McCulloch, M..........................................................74
McCully, Sophy R. ..................................................78
McMahon, Kelton W. ........................................16, 44
McMillan, Pat A. .....................................................79
Merle, Didier ...........................................................24
Michener, Robert .....................................................14
Millner, R. S. .....................................................42, 78
Miyaji, Tsuzumi.................................................80, 81
Modin, Johan ...........................................................30
Montagna, P.............................................................74
Morales-Nin, Beatriz ...............................................31
Morimoto, Maki.......................................................52
Morize, E. ................................................................87
Munk, Kristen M. ....................................................82
Murray, J. B. ..........................................................110
Mutvei, Harry ..........................................................22
Nakamura, Nobuko............................................59, 83
Nedreaas, Kjell ..................................................30, 78
Neil, Jodi..................................................................82
Ninemann, Ulysses ..................................................30
Nixon, Scott W. .......................................................45
Noé, Sibylle U. ..................................................84, 85
Norris, Richard D...............................................13, 33
Oguri, K. ..................................................................98
Oliveira, Marilia D. M. ............................................70
Ortlieb, Luc......................................37, 38, 40, 41, 69
Ourbak, Timothee ....................................................86
Pace, M. L..............................................................107
Page, Nicolas A. ......................................................93

July 17-21, 2007 z St. Petersburg, Florida USA

Paillard, C................................................................ 87
Palzer, Todd A......................................................... 29
Patterson, William P................................................ 60
Paulet, Y. M............................................................. 87
Pedersen, Rolf Birger .............................................. 30
Peyer, Suzanne ........................................................ 49
Pilling, G. M...................................................... 42, 78
Poitrasson, F. ........................................................... 69
Portell, Roger W........................................................ 8
Poulain, C. ............................................................... 87
Quinn, Terrence M. ................................................. 21
Quitmyer, Irvy R. ................................................ 8, 58
Rasmussen, Linda.................................................... 79
Renard, Maurice ................................................ 24, 67
Reveillaud, Julie ...................................................... 84
Richardson, Christopher A. ........................ 12, 27, 71,......................................... 88, 89, 90, 91, 105
Richter, D. ............................................................... 48
Risk, Michael J. ....................................................... 92
Rodland, David L. ................................................... 93
Rollion-Bard, Claire .............................................. 102
Romanek, C. S......................................................... 51
Romanek, Christopher S................................ 3, 17, 18
Ropert, Michel......................................................... 67
Ross, Steve W.......................................................... 50
Runnegar, Bruce ...................................................... 54
Sander, Martin ....................................................... 102
Sano, Yuji................................................................ 81
Saurel, C. ................................................................. 90
Savarese, Michael...................................................... 8
Schöne, Bernd R........................ 9, 56, 80, 93, 94, 105
Schue, John................................................................ 9
Scourse, James D....................................... 12, 88, 105
Sealy, Judith C......................................................... 28
Sedberry, George R. .................................................. 3
Sha, Jingeng............................................................. 55
Shcherbich, Zhanna N. ........................................ 4, 10
Sherwood, Owen A. ................................................ 92
Shirai, Kotaro .......................................................... 81
Simoes, M. G........................................................... 51
Sizemore, Bob ......................................................... 29
Skadal, J. ................................................................. 78
Sliko, Jennifer L. ..................................................... 95
Snover, Melissa L.................................................... 96
Stamm, R. .............................................................. 110

Stinson, Lani............................................................ 16
Surge, Donna ............................................. 34, 97, 106
Sutherland, Sandra J. ............................................... 77
Swart, P. K............................................................... 43
Tada, Yohei ............................................................. 98
Takesue, Renee K.................................................... 99
Tanabe, Kazushige ...................................... 80, 81, 98
Tao, Kai ................................................................. 100
Taviani, M. .................................................. 72, 73, 74
Taylor, Frederick W. ............................................... 21
Thorrold, Simon ...................................................... 16
Thresher, Ronald E................................................ 101
Tomas, Javier........................................................... 31
Troelstra, Simon R................................................. 104
Tütken, Thomas..................................................... 102
Ushikubo, Taka ............................................... 49, 107
Valiela, Ivan ............................................................ 14
Valley, John W. ............................................... 49, 107
Vancolen, Séverine................................................ 103
Velasco, Frederico............................................. 37, 41
Vendrell, B. ............................................................. 74
Verrecchia, Eric P...................................... 24, 67, 103
Versteegh, Emma A. A.......................................... 104
Vonhof, Hubert B. ................................................. 104
Wahl, Martin ........................................................... 66
Walker, Karen Jo................................................... 106
Wallace, Heather V. E. ............................................ 20
Wanamaker, Jr., Alan D. ....................................... 105
Wang, Huayu........................................................... 39
Wang, Ting............................................................ 106
Weidel, B. C. ......................................................... 107
Whatley, Kelley S.......................................... 108, 109
Wilson, Nick.......................................................... 101
Wilson, Stephen A................................................... 64
Wingard, G. L........................................................ 110
Wisshak, Max........................................................ 111
Wissink, Christine ................................................... 36
Witbaard, R. ...................................................... 47, 48
Wolff, Matthias ....................................................... 41
Woo, Kyung Sik ...................................................... 61
Yamagata, Toshio.............................................. 52, 83
Yancey, Thomas E................................................... 39
Yoon, Seok Hoon .................................................... 61
Zevallos, Sheyla ...................................................... 41
Zhang, Zengjie......................................................... 93

115

First International Sclerochronology Conference

Notes

116

July 17-21, 2007 z St. Petersburg, Florida USA

Notes

117

First International Sclerochronology Conference

Notes118