Program and Abstracts

June 5th-9th, 2016
Portland, Maine, USA5th-9th June, 2016 • Portland, Maine, USA

4th International
Sclerochronology Conference
5th - 9th June, 2016
Portland, Maine

Program and Abstracts

1

4th International Sclerochronology Conference, ISC 2016

Organizing Committee
Fred Andrus (University of Alabama)
Bryan Black (University of Texas at Austin)
Kristine Delong (Louisiana State University)
David Gillikin (Union College)
David Goodwin (Denison University)
Linda Ivany (Syracuse University)
Donna Surge (University of North Carolina - Chapel Hill)
Al Wanamaker (Iowa State University)

Conference Planning and Management
Jennifer Vit (Iowa State University)

Supplementary Organizational Support
Jared Ballew (Iowa State University)
Madelyn Mette (Iowa State University)
Mike Retelle (Bates College)
Nina Whitney (Iowa State University)

Abstract Volume
Chief Editor: Nina Whitney
Editorial Support: Jared Ballew, Madelyn Mette, Alan Wanamaker
Printed at Iowa State University

Recommended citation: Author or authors, 2016. 4th International Sclerochronology
Conference, 5-9 June 2016, Portland, Maine, USA, Program and Abstracts.
Copyright and responsibility for the scientific content in this program lie with thecontributing authors.
Cover photo by Mike Retelle, Bates College, Maine2

5th-9th June, 2016 • Portland, Maine, USA
Dear Friends and colleagues,
On behalf of the organizing committee, welcome to beautiful and historic Portland, Maine (USA)home of the 4th International Sclerochronology Conference (ISC 2016). It has been a real pleasure
to watch the field of sclerochronology develop so much since the first meeting in St. Petersburg,
Florida in 2007. The high quality of the meetings in Florida (ISC 2007), Mainz, Germany (ISC2010) and Caernarfon, North Wales (ISC 2013) made the organizing committee of ISC 2016 strive
to also develop a world-class conference on sclerochronology. We especially want to welcome newmembers of the sclerochronology community to the conference!
For ISC 2016, we established topical sessions that we thought best reflected where the field ofsclerochronology is now and where it seems to be moving. These include: Proxy Development:
Problems and Opportunities, Scleroarchaeology, Growth and Bioenergetics, Deep-time Evolution
and Ecology, Climate and Oceans: Past and Present, Environmental Monitoring and Conservation
Paleobiology, Fisheries Ecology and Management, and Sclerochronology in the Classroom. It
has become more and more evident by the number of high-quality peer reviewed journal articles
that sclerochronology is an essential tool in the natural sciences. The interdisciplinary nature ofsclerochronology along with its workers will help address many important problems facing theplanet and our global society now and in the future. It is an exciting time to be a sclerochronologist.
The organizing committee is especially thankful to the keynote speakers, all of whom areinternationally recognized experts, for bringing their unique experience and enthusiasm forsclerochronology to Portland. We also thank all of our authors for submitting their best work for thisconference. Our single most important goal is that ISC 2016 will be a platform of discovery, debate,
discussion, networking, collaboration, and a bit fun. Based on the contributions that we received, weare certain that we will meet this goal!
The venue for ISC 2016 is in the newly renovated Westin Portland Harborview Hotel in the heartof Portland, Maine. The waterfront, shops, eateries, and other local attractions are just a short walkaway. If there is anything that the organizing committee can do to help make this conference more
successful, please let us know. The organizing committee is thankful to our sponsors for providing
financial support. Please be sure to visit with the vendors and sponsors during the meeting. They
would be thankful for any future business that you may require. We are indebted to many people forhelping this conference come to fruition. Of particular note, we thank Jennifer Vit from the Iowa
State University Conference Planning Office for her huge amount of help and expert guidance.
Additionally, we thank Madelyn (Maddie) Mette (PhD candidate, Iowa State University) for her
immense commitment to ISC 2016 and for making the behind the scenes things work so well! We
wish you a safe, enjoyable, and productive conference!
With warm regards,
Fred Andrus (University of Alabama), Bryan Black (University of Texas at Austin), Kristine Delong(Louisiana State University), David Gillikin (Union College), David Goodwin (Denison University),
Linda Ivany (Syracuse University), Donna Surge (University of North Carolina), and Al Wanamaker(Iowa State University)34th International Sclerochronology Conference, ISC 2016
The organizers of ISC 2016 are very thankful for the generous support of the following sponsors.
Please take time during the conference and visit these exhibitors.
Silver Sponsor
Iowa State University – Department of Geological and Atmospheric Sciences & Stable Isotope
Paleoenvironments Research Group
University of North Carolina – Chapel Hill: College of Arts and Sciences & Department of
Geological Sciences

Bronze Sponsor
Electro Scientific Industries, Inc. (ESI)

Exhibiting Sponsor
Electro Scientific Industries, Inc. (ESI)
National Ocean Sciences Accelerator Mass Spectrometry, Woods Hole Oceanographic Institution
Paleontological Research Institute
Paleontological Society
Perkin Elmer
Thermo Fisher ScientificAdvertising Sponsor
Beta Analytics
National Ocean Sciences Accelerator Mass Spectrometry, Woods Hole Oceanographic Institution
Plos One
Syracuse University – Department of Earth Sciences45th-9th June, 2016 • Portland, Maine, USA

Schedule

Refreshment breaks sponsored by Electro Scientific Industries, Inc. (ESI)
5

4th International Sclerochronology Conference, ISC 2016
S U N D A Y , 	
   J U N E 	
   5 T H , 	
   2 0 1 6 	
  17:30 – 19:30

Icebreaker and Registration (Ballroom pre-function space)M O N D A Y , 	
   J U N E 	
   6 T H , 	
   2 0 1 6 	
  09:00 – 09:20

S E S S I O N 	
  
	
  

6

	
  

Introductory Remarks and Welcome

	
  
	
  

P R O X Y 	
   D E V E L O P M E N T : 	
   P R O B L E M S 	
   & 	
   O P P O R T U N I T I E S 	
  Session	
  Chair:	
  Donna	
  Surge	
  (morning)	
  and	  Bryan	
  Black	
  (afternoon)	
  09:20 – 09:50

Jochen Halfar (Keynote)
Coralline algal paleoclimatology – A review of current status and challenges

09:50 – 10:10

Zita Kelemen
Reconstructing past variability in African hydrology using freshwater bivalve shellgeochemistry: A multi-year calibration from the Oubangui and Niger Rivers

10:10 – 10:30

Liza Roger
Geochemical and crystallographic study of two species of coolwater bivalves (Fulvia
tenuicostata and Soletellina biradiata) from southwestern Australia

10:30 – 10:50

Refreshment Break

10:50 – 11:10

Madelyn Mette
Using shell-based proxy records from northern Norway to evaluate high latitude
impacts of the Atlantic Multidecadal Oscillation

11:10 – 11:30

Merinda Nash
Understanding cellular-scale controls on Mg uptake in crustose coralline algae

11:30 – 11:50

Phoebe Chan
Recent decline in skeletal density and calcification rates of subarctic crustose coralline
algae

11:50 – 13:20

Lunch (provided; Longfellow Room)

13:20 – 13:40

Michèlle LaVigne
Southeast Gulf of Mexico corals reveal annual barium cycles

13:40 – 14:00

Stefania Milano
Mechanical and structural response of Cerastoderma edule shell to acidification

14:00 – 14:20

Bernd Schöne
Bivalve Sr/Ca(shell) heterogeneity and microstructures – Are geochemical variations at the
micrometer-scale masking potential environmental signals?

14:20 – 14:40

Refreshment Break5th-9th June, 2016 • Portland, Maine, USA

14:40 – 15:00

Julien Thébault
Great scallop shells as geochemical archives of phytoplankton dynamics in the bay of Brest(France)

15:00 – 15:20

Kohki Sowa
Spatial distribution of low molecular weight organic matter in micrometer skeletal structureof Acropora and Porites coral

15:20 – 15:40

David Gillikin
Reconstructing hydrological changes over the past century in Central Africa using freshwaterbivalve shells

15:40 – 15:50

Refreshment Break (10 minutes)

S E S S I O N 	
  
	
  

	
  

	
  
	
  

S C L E R O A R C H A E O L O G Y 	
  Session	
  Chair:	
  Kristine	  DeLong	  15:50 – 16:20

Marcello Mannino (Keynote)
The challenges of a high-resolution archaeology: Sclerochronological and isotopic
approaches in perspective

16:20 – 16:40

Meghan Burchell
Isotope sclerochronology and hunter-gatherer seasonality: Archaeological landscapesfrom the Pacific and Atlantic coasts of Canada

16:40 – 17:00

Ryan Harke
Sclerochronology of a large predatory gastropod (Busycon sinistrum) to determine lateprehistoric seasonality at St. Joseph Bay, Florida

17:00 – 17:10

Refreshment Break (10 minutes)

17:10 – 17:30

Fred Andrus
Archaeological applications of molluscan nitrogen isotope analyses

17:30 – 17:50

Peter Müller
Application of clumped isotopes in shell midden sclerochronology

17:50 – 18:10

Donna Surge
Determining season of harvest in shells of the European limpet (Patella vulgata) frommodern and medieval collections

	
  

	
  

7

4th International Sclerochronology Conference, ISC 2016
T U E S D A Y , 	
   J U N E 	
   7 T H , 	
   2 0 1 6 	
  08:55 – 09:00

S E S S I O N 	
  
	
  

	
  

	
  
	
  

G R O W T H 	
   A N D 	
   B I O E N E R G E T I C S 	  Session	
  Chair:	
  David	  Gillikin	
  09:00 – 09:30

Brian Helmuth (Keynote)
It’s not all death and destruction: Thermal performance, energetics and the key role ofmonitoring growth responses to global climate change

09:30 – 09:50

Ariadna Purroy
The interaction of reproduction and shell growth in the bivalve Callista chione

09:50 – 10:10

Irene Ballesta Artero
Environmental factors driving the valve gape activity of the bivalve Arctica islandica inNorthern Norway

10:10 – 10:30

Michael Carroll
Shell growth and environmental control of methane-associated thyasirid bivalves from
Svalbard cold seeps

10:30 – 10:50

Refreshment BreakS E S S I O N 	
  
	
  

8

Announcements

	
  

	
  
	
  

D E E P -­‐ T I M E 	
   E V O L U T I O N 	
   A N D 	
   E C O L O G Y 	
  Session	
  Chair:	
  Fred	  Andrus	  10:50 – 11:20

Seth Finnegan (Keynote)
Paleobiology Needs Your Help

11:20 – 11:40

Andrew Johnson
Evidence, cause and consequence of exceptionally rapid growth amongst Pliocene scallopsof the US eastern seaboard

11:40 – 12:00

David Moss
Latitudinal variation of lifespans and growth rates in modern marine bivalves

12:00 – 12:20

Linda Ivany
Growing a sea monster: Isotope ecology of a giant heteromorph ammonite

12:20

Boxed lunches provided(12:45)

Departure for “Southern Maine Quaternary Geology Field Trip” Excursion. Return by 18:00.

19:00 – 21:00

Poster Session (Eastland Grand Ballroom)

	
  

	
  

5th-9th June, 2016 • Portland, Maine, USA
W E D N E S D A Y , 	
   J U N E 	
   8 T H , 	
   2 0 1 6 	
  08:55 – 09:00

S E S S I O N 	
  
	
  

	
  

Announcements

	
  
	
  

C L I M A T E 	
   A N D 	
   O C E A N S : 	
   P A S T 	
   A N D 	
   P R E S E N T 	
  Session	
  Chair:	
  Al	
  Wanamaker	
  (morning)	
  and	
  Phoebe	
  Chan	  (afternoon)	
  09:00 – 09:30

Kim Cobb (Keynote)

09:30 – 09:50

Juan Estrella-Martínez
Evaluating the strength and temperature variability of the North Atlantic current for thesecond half of the last millennium using an Arctica islandica-derived increment series

09:50 – 10:10

Melita Peharda
The bivalve Glycymeris pilosa as a multidecadal environmental archive for the Adriatic andMediterranean Seas

10:10 – 10:30

Nina Whitney
An annually resolved, shell-derived oxygen isotope record since the late Little Ice Age fromthe Gulf of Maine: Implications for ocean circulation changes in the western North Atlantic

10:30 – 10:50

Refreshment Break

10:50 – 11:10

Fabian Bonitz
A 388-year Arctica islandica shell-based chronology from the Faroese Shelf: Implications
for a better understanding of the natural climate variability of the Faroe Current

11:10 – 11:30

Stella Alexandroff
Reconstructing Holocene temporal hydrographic variability in Scottish Shelf Seas using dog
cockle shells (Glycymeris glycymeris)

11:30 – 11:50

Branwen Williams
Impact of skeletal heterogeneity and treatment method on interpretation of environmental
variability from the skeletons of deep-sea gorgonian corals

11:50 – 13:20

Lunch (on your own)

13:20 – 13:40

James Scourse
Annually-resolved North Atlantic marine climate over the last millennium: the ULTRA
series13:40 – 14:00

David Reynolds
An integrated spatial data-model approach to reconstructing and understanding Atlantic
meridional overturning circulation

14:00 – 14:20

Eric Otto Walliser
Short-term climate variability in Central Europe during the Oligocene – A story told byglycymerids

14:20 – 14:40

Refreshment Break9

4th International Sclerochronology Conference, ISC 2016

14:40 – 15:00

Maria Pyrina
Test of North Atlantic sea-surface-temperature reconstructions with pseudo proxyexperiments over the last millennium

15:00 – 15:20

Kristine DeLong
Salinity shifts in the southwest tropical Pacific from the Little Ice Age to the 20th century

S E S S I O N 	
  
	
  
	
  
	
  

	
  

	
  
	
  
	
  

E N V I R O N M E N T A L 	
   M O N I T O R I N G 	
   A N D 	
   C O N S E R V A T I O N 	   	
  P A L E O B I O L O G Y 	
  Session	
  Chair:	
  Linda	  Ivany	  15:20 – 15:50

Greg Dietl (Keynote)
Conservation paleobiology meets sclerochronology

15:50 – 16:10

Paul Butler
The regulatory context of the use of biochronologies for baseline environmental monitoring

16:10 – 16:20

Refreshment Break (10 minutes)

16:20 – 16:40

Justin McNabb
Isotope sclerochronology and season of annual growth formation in the marine bivalve,
Astarte borealis, from Arctic and cold-temperate seas

16:40 – 17:00

Stephen Durham
Testing the effect of climate warming on oyster life history using geohistorical records

17:00 – 17:20

Daan Vanhove
Do oxygen isotope ratios in unionid shells reflect continental African hydroclimate
variability?

18:45

Walk to Peaks Island ferry for 19:15 departure. Return ferry embarks at 21:45.
Ferry to Peaks Island takes 20 minutes.

	
  

10

	
  

5th-9th June, 2016 • Portland, Maine, USAT H U R S D A Y , 	
   J U N E 	
   9 T H , 	
   2 0 1 6 	
  08:55 – 09:00

S E S S I O N 	
  
	
  

	
  

Announcements

	
  
	
  

F I S H E R I E S 	
   E C O L O G Y 	
   A N D 	
   M A N A G E M E N T 	
  Session	
  Chair:	
  Meghan	  Burchell	
  and	  David	
  Goodwin	
  09:00 – 09:30

John Morrongiello (Keynote)
Otoliths: From individuals to assemblages in a changing world

09:30 – 09:50

Lisa Kerr
Reconstructing environmental histories of Atlantic cod in the Gulf of Maine

09:50 – 10:10

Karin Limburg
Losing track of time: Is hypoxia in part to blame for Baltic cod aging problems?

10:10 – 10:30

Beth Matta
Otolith biochronologies reveal latitudinal differences in growth of Bering Sea yellowfin sole
Limanda aspera

10:30 – 10:50

Refreshment Break

10:50 – 11:10

Peter van der Sleen
Low-frequency variability in a centennial-length biochronology of Bering Sea Pacific ocean
perch (Sebastes alutus)

11:10 – 11:30

Bryan Black
Crossdating and preservation of signal strength in growth increment chronologies

11:30 – 11:50

Phil Hollyman
Micro-scale chemical analysis of statoliths from the whelk Buccinum undatum: validation of
a novel age determination method for fisheries management

11:50 – 12:10

Pierre Poitevin
A new method for age and growth rate determinations of the Atlantic surf clam (Spisulasolidissima), based on internal growth lines in ligament cross-sections

12:10 – 14:00

Lunch Banquet, Student Awards, Future Meeting Planning11

4th International Sclerochronology Conference, ISC 2016P O S T E R 	
   P R E S E N T A T I O N S 	
  Presenting authors are listed below in alphabetical order with abstract titles.
Jared Ballew
Development of a species-specific oxygen isotope transfer function for Arctica islandica shells: Insights from atemperature experiment
Christine Bassett
Clams and climate: Implications for reconstructing paleoseasonality in southern Alaska
Fabian Bonitz
Temperature reconstructions based on δ18O measurements in bivalve shells from the Faroese Shelf
Shibajyoti Das
Diet of fossil and modern bivalves and gastropods revealed by carbon and nitrogen isotopes of shell-associated organic
matterKristine DeLong
Save our Marine Annually Resolved Proxy Archives (MARPA)!
Amy Featherstone
Multiproxy reconstruction of seawater temperature in the bay of Brest using shells of dog cockles, Glycymeris
glycymeris
Teresa Franco
Seasonal patterns in shells of Concholepas concholepas and its application at the archaeological site of Camarones 14(Camarones River Valley, Chile)
Megan Freiberger
Evidence for growth rate nonlinearity in bamboo corals
Pedro Freitas
Upwelling seasonality in the Iberian upwelling system from shell δ13C records in the bivalve Glycymeris glycymeris
Thomas Geeza
Trace and major element ratios in Elliptio dilatatus shells as indicators of surface water quality in Western
Pennsylvania
David Gillikin
Paleoclimate reconstruction from oxygen isotopes in a coral skeleton from East Africa
Lauren Graniero
Detecting seasonal variations in nitrogen and carbon sources to an impacted river and its estuary using bivalve shell
δ15N and δ13C values

125th-9th June, 2016 • Portland, Maine, USA
Steffen Hetzinger
Reproducibility of Clathromorphum compactum coralline algal Mg/Ca ratios and calibration to high-resolution sea
surface temperature data
Alaina Hickey
Paleoecological implications of nitrogen and carbon isotopic data from organic material in Devonian rugose corals
Emily Judd
Seasonal variation in temperature and precipitation during Eocene cooling inferred from Antarctic bivalves
Daniel Killam
Geochemical evidence for the presence of photosymbiosis in Early Jurassic lithiotid bivalve
Natasha Leclerc
Shellfishing through the Holocene in British Columbia: Insights from oxygen isotope sclerochronology
Vilde Melvik
Marine climate variability of the Irminger Current based on growth increments in the bivalve Arctica islandica: A
molluscan sclerochronological approach
Alexandra Németh
Sclerochronological comparison of two dog cockle (Glycymeris glycymeris L.) populations from the southeastern North
Atlantic
Richard Patton
The impacts of ocean acidification and increasing temperature on shell properties of intertidal bivalve molluscs
Michael Retelle
Mid and Late Holocene marine paleoenvironmental reconstructions from Ingøya and Rolvsøya, northern Finnmark,Norway	  Alejandro Román González
Advances in developing Antarctic sclerochronogical archives from the marine bivalve Yoldia eightsi
Bernd Schöne
The Mediterranean Sea during the Pleistocene - Bivalve shells and their potential to reconstruct decadal and seasonal
climate signals of the past
Anna Sparrow
Tides & traditions: Insights into indigenous hunter-fisher-gatherer shellfishing with sclerochronology
Larry Taylor
Reconstruction of humpback whale migration via isotopic analysis of coronulid barnacle shells
Julien Thébault
Growth, longevity and stable isotope composition of European date mussels Lithophaga lithophaga from eastern
Adriatic
Tamara Trofimova
Environmental variability revealed in sclerochronological records of Arctica islandica from the northern North Sea

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4th International Sclerochronology Conference, ISC 2016
Alan Wanamaker
Highly dynamic marine radiocarbon reservoir effect in the Gulf of Maine since AD 1685
Jacob Warner
Assessing seasonal variability and archaeological season of harvest in North-Central coastal Peru using the short-Livedbivalves Donax obesulus and Mesodesma donacium
Siobhan Williams
Comparing climate signals obtained from encrusting and free-living southwest Greenland coralline algae
Rob Witbaard
Seasonal timing of shell and tissue growth in Arctica islandica
Christiane Yeman
Continuous 14C analysis of marine carbonates by laser ablation coupled with AMS
Liqiang Zhao
Effects of calcium availability on shell growth rate and element composition of Corbicula fluminea (Bivalvia)

145th-9th June, 2016 • Portland, Maine, USA

Keynote Biographies and Abstracts

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4th International Sclerochronology Conference, ISC 2016

Congress Street, Arts District
Portland, Maine, USA16

5th-9th June, 2016 • Portland, Maine, USA

Session 1. Proxy Development: Problems and Opportunities
Jochen Halfar
Dept. of Chemical and Physical Sciences, University of Toronto, Mississauga, ON, Canada
Biography:
Dr. Jochen Halfar is an Associate Professor and Associate Chair in the Department of Chemicaland Physical Sciences at the University of Toronto Mississauga (Canada). Dr. Halfar holds a B.S.
in Geology and Paleontology from the University of Heidelberg (Germany) and a M.S. in Geology
from the University of Göttingen (Germany). He obtained a PhD. in Geological and Environmental
Sciences from Stanford University (USA). Dr. Halfar’s research is focused on deciphering
paleoclimates on different time scales ranging from the past centuries to the Neogene usinggeochemical, sedimentological, and oceanographic approaches. His recent work includes developing
proxy records from information contained in calcified growth bands of long-lived coralline red algae
to reconstruct sea surface temperatures of extratropical seas using state-of-the-art microanalyticalgeochemical techniques.
Abstract: Coralline algal paleoclimatology – A review of current status and challenges

Coralline algae are a globally distributed group of shallow marine benthic calcifiers that can form annual
growth increments in a high-Mg calcite skeleton. Over the past 15 years a number of both free-living andencrusting coralline algal genera have been tested for their suitability as climate recorders and to date several
multicentury long reconstructions of ocean climate have been generated. Coralline algal proxy studies span
regions ranging from the tropics to arctic latitudes, with most studies focussing on mid- and high-latitude
regions of the Northern Hemisphere. In high latitudes coralline algae are considered to be the single mostabundant shallow benthic marine calcifier, sometimes covering up to 100% of the seafloor in the shallow
photic zone. Proxy studies include both free-living rhodolith nodules and attached crusts forming build-ups
on hard substrate. Environmental interpretation of rhodoliths, which are generally found on soft-substrateseafloor, is complicated by the fact that rhodoliths are overturned at infrequent intervals by water movement
and benthic organisms, with opposite nodule sides receiving contrasting light conditions at any given time.
This severely limits proxy reconstructions, since skeletal growth and trace element incorporation of thephotosynthetic coralline algae is primarily controlled by light and temperature variability. In contrast, crustsof the massive growing coralline alga Clathromorphum sp., that forms abundant build-ups throughout theSubarctic and Arctic including regions seasonally covered by sea ice, remain in a fixed position throughout
their up to 650 year long lifespan, while faithfully recording environmental conditions. With an absence of an
ontogenetic growth decline and annual growth rates varying between 80-400 µm as a function of temperatureand light variability, seasonal to annual resolution proxy reconstructions have been possible in regions as far
as 73°N. To date, Clathromorphum sp. has yielded interpretations of past ocean temperature, cloud cover,freshwater influx, ocean pH and sea-ice conditions. The latter application is currently the focus of intense
research, since the Arctic-wide occurring Clathromorphum is the only annual resolution marine sea ice proxyavailable to date. However, our understanding of Clathromorphum proxy recording has been hampered by aninability to achieve representative algal growth in controlled mesocosm experiments. Those experiments were
designed to gain a better understanding of the relative influence of temperature and light on the photosynthetic
proxy, evaluate interspecimen variability as well as to shed light onto calcification mechanisms, which to dateare poorly understood. In addition to ongoing efforts of proxy calibration, basic questions such as distribution
and occurrence of Clathromorphum buildups suitable for sclerochronological work are being addressed byupcoming expeditions to the core Arctic.

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4th International Sclerochronology Conference, ISC 2016

Session 2. Scleroarchaeology
Marcello Mannino

Dept. of Archaeology, School of Culture and Society, Aarhus University, Højbjerg, Denmark; Dept.
of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Biography:
Dr. Marcello Mannino is an Associate Professor in the Department of Archaeology at Aarhus
University (Denmark) and an Associate Scientist with the Department of Human Evolution at the
Max Planck Institute for Evolutionary Anthropology (Germany). He holds a B.S. with Honors in
Archaeology and obtained a PhD. in Archaeology from the University of London (United Kingdom).
Dr. Mannino’s research interests include human palaeoecology and the reconstruction of pastenvironments, subsistence, diet, and mobility. He is currently investigating human dietary change
from the late Middle Palaeolithic, through the Upper Palaeolithic, and to the early Neolithic bymeans of stable isotope analyses on skeletal remains of Neanderthals and Modern Humans
Abstract: The challenges of a high-resolution archaeology: sclerochronological and isotopic
approaches in perspective

The palimpsest nature of archaeological deposits and their often coarse temporal resolution (e.g. in the orderof decades, centuries or millennia) allow us to study phenomena and processes at broad scales of observation,
which is useful to evaluate culture change over long periods of time. Sites, however, are also repositories
of organic remains of past human actions, which constitute archives of past climates and environments
inadvertently preserved for us by their occupants. Sclerochronology and isotope analyses on incremental
skeletal structures, such as those of molluscan shells, offer us the possibility of attaining high-resolution
environmental and archaeological data, on yearly, seasonal, monthly, weekly or even daily scales. Highresolution data is essential to assess whether, or in what way, changes in human behavior may have been
linked to climate or changing environments, given that it is to short-term changes that humans would haveadapted to. This lecture addresses how this is currently achieved by sclero-archaeology, as well as what
methods and themes of inquiry should be developed in the future.
An immediate strategic goal is to establish as palaeo-seasonality proxies all mollusc taxa which arearchaeologically common, by studying their living counterparts. These developments should not only beaimed at reconstructing season of mollusc collection, as is usually done, but at using shells as climatic andenvironmental records relevant for understanding past human behavior. Methodological progress should bemade to improve radiocarbon dating projects based on shells and to expand the range of sclero-archaeologicalapplications to provenancing shell artefacts. In fact, despite the fact that shell ornaments are proxies of pastsymbolism, languages or exchange networks, very little effort has been devoted to unravel the life histories ofthese shell artefacts, thereby limiting their potential as invaluable proxies of human behavior.
The rewards for embarking on targeted sclerochronological and isotopic studies of shells from a variety ofarchaeological periods and cultures are there for the taking. If similar strategies are pursued, high-resolution
research may allow us to tackle the ‘grand challenges for archaeology’ (Kintigh et al. 2014) and contribute toour understanding of how people in the past responded to abrupt environmental change over the short term.

18

5th-9th June, 2016 • Portland, Maine, USA

Session 3. Growth and Bioenergetics
Brian Helmuth
Department of Marine and Environmental Sciences, Northeastern University, Boston, MA, USA
Biography:
Dr. Brian Helmuth is a Professor of Marine and Environmental Sciences at Northeastern University
in Boston, Massachusetts. He holds a B.S. in Biology from Cornell University and obtained an
M.S. in Biology at Northeastern University. He earned a Ph.D. in Zoology from the Universityof Washington. Dr. Helmuth’s research explores the effects of climate and climate change on thephysiology and ecology of marine organisms. He uses thermal engineering techniques, including a
combination of fieldwork, remote sensing and mathematical modeling, to explore the ways in which
the environment determines the body temperatures of coastal marine animals such as mussels andseastars. His students study a wide range of topics and organisms, and in recent years the emphasisof his lab has shifted to include a large focus on the development of educational tools such as virtual
reality environments and serious games to engage K-12 students and the general public in marine
biology.
Abstract: It’s not all death and destruction: Thermal performance, energetics and the key roleof monitoring growth responses to global climate change
By definition, global climate change is affecting organisms and ecosystems worldwide, but these
impacts often play out at incredibly local scales. For example, the ability of organisms to use
microclimates can lead to differences in environmental stress over the scale of tens of cm that canexceed much larger-scale patterns observed over tens of degrees of latitude. An increasing numberof studies are showing that rather than conforming to simple latitudinal gradients, many species
live along what may best be considered as geographic mosaics of environmental stress. Moreover,non-climatic and climatic stressors do not always conform to the same geographic patterns, so that
exposure to multiple stressors can be highly complex. Forecasting the likelihood of future responses
to environmental change therefore requires not only that we understand the complicated ways inwhich multiple stressors affect organisms to create “winners” and “losers,” but also that we gaina better understanding of how the temporal and spatial coincidence of these stressors will occur
in nature. Energetics modeling provides an effective means of integrating the consequences ofmultiple stressors to organismal physiology. A primary finding of many of these studies is that thefirst observable impacts of climate change are not simply the result of rare but lethal extreme events,
but also the cumulative effects of more chronic levels of stress on patterns of growth, reproduction
and fitness. The production of hindcasting and nowcasting models of nonlethal responses toenvironmental change based on first principles, which can then be validated using cutting-edgesclerochronology methods in animals such as bivalves, offers new opportunities for interdisciplinary
collaboration that will likely provide critical insights into climate change ecology.

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4th International Sclerochronology Conference, ISC 2016

Session 4. Deep-time Evolution and Ecology
Seth Finnegan

Department of Integrative Biology, University of California, Berkeley, CA, USA
Biography:

Dr. Seth Finnegan is an Assistant Professor of Integrative Biology at the University of California, Berkeley.
He holds a B.S. from the University of Chicago and obtained an M.S. and Ph.D. in Geological Sciences fromthe University of California, Riverside. Dr. Finnegan’s research integrates data from a variety of sources
including field observations, lab work, and literature databases to study the nature of organism-environment
interactions through time. He investigates patterns of extinction selectivity, environmental proxies, andmethods to reconstruct the structure and function of marine ecosystems through time, with a recent focus on
the Ordovician Period (488 to 444 million years ago).

Abstract: Paleobiology needs your help

The Phanerozoic marine fossil record presents many striking patterns that remain poorly understood despite
decades of study. Many long-term macroevolutionary and paleoecological trends are thought to have been
driven by organism-environment interactions, but understanding of these trends is hampered by lack of
information about both the environments in which early animals evolved and the metabolisms of theseanimals. Because they focus on the intersection of organismal growth and environment, sclerochronologicalstudies have enormous potential to bring clarity to these and other paleobiological controversies. My agenda
in attending this meeting is, first, to learn from the sclerochronology community, and second, to bring someoutstanding problems to your attention. I will focus on two broad problems, though there are many otherareas in which sclerochronological studies can contribute to our understanding of deep-time paleobiologicalpatterns. Our knowledge of deep-time climate changes comes primarily from the oxygen isotope record (δ18O)of biogenic carbonates and phosphates. Classic studies by Veizer and colleagues established that the average
preserved δ18O values of tropical-subtropical shallow-water calcifiers rose by ~6‰ from the Cambrian tothe present. Taken as a record of sea surface temperatures this implies that early animals routinely survived
temperatures in excess of 50˚C. Alternative interpretations include pervasive diagenetic alteration of ancientfossils and progressive δ18O enrichment of the marine oxygen reservoir through time. The latter model is
not supported by recent clumped isotope studies, but these studies themselves suffer from necessarily coarse
sampling and consequent inability to resolve signals in single growth increments. Determining the properinterpretation of the Phanerozoic δ18O trend is of first-order importance for understanding the nature of
the environments in which early animals arose and evolved, and sclerochronology can play a critical role
in resolving this debate. The mean body size of fossilized marine animals has also increased through thePhanerozoic. Along with concomitant increases in motility, proportion of predators, and the compositionof primary producer communities this has been taken as evidence that mean per-capita metabolic rates
have increased. On shorter timescales, many lineages exhibit reduced size in the aftermath of major mass
extinction events. Changes in mean size can result from changes in lifespan or in growth rate, and thesehave quite different implications regarding the process(es) driving evolutionary trends. However, little is
known about growth rates or lifespans in the great majority of extinct clades. Even in modern calcifying
groups, comparatively little is known about the controls on growth rate: are growth rates more strongly
determined by extrinsic environmental conditions such as temperature and productivity or by intrinsic aspectsof physiology that may be conserved across broad phylogenetic groups? Such uncertainties hamper efforts
to reconstruct ancient ecosystems and to understand the environmental drivers of macroevolutionary trends.
Sclerochronologists have developed a mature set of tools that, carefully applied, can shed considerable lighton the evolution of marine ecosystems through time.

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Session 5. Climate and Oceans: Past and Present
Dr. Kim Cobb
School of Earth and Climate Sciences, Georgia Institute of Technology, Atlanta, GA, USA
Biography:

Dr. Kim Cobb’s research uses corals and cave stalagmites to probe the mechanisms of past, present, andfuture climate change. She received her B.A. from Yale University in 1996, and her Ph.D. in Oceanography
from the Scripps Institute of Oceanography in 2002. She spent two years at Caltech in the Department of
Geological and Planetary Sciences before joining the faculty at Georgia Tech in 2004. Dr. Cobb has sailed on
oceanographic cruises to the deep tropics and led caving expeditions to the rainforests of Borneo in support ofher research. Dr. Cobb has received numerous awards for her research, most notably a NSF CAREER Awardin 2007, and a Presidential Early Career Award for Scientists and Engineers in 2008. She is an Editor for
Geophysical Research Letters, and sits on the international CLIVAR Pacific Panel, and the Advisory Council
for the AAAS Leshner Institute for Public Engagement. As a mother to four, Dr. Cobb is a strong advocate
for women in science. She is also devoted to the clear and frequent communication of climate change to the
public through speaking engagements and social media.

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4th International Sclerochronology Conference, ISC 2016

Session 6. Environmental Monitoring and Conservation
Paleobiology
Dr. Greg Dietl
Paleontological Research Institution, Ithaca, NY, USA
Biography:
Dr. Gregory P. Dietl is Curator of Cenozoic Invertebrates at the Paleontological Research Institution(PRI) and an Atkinson Center for a Sustainable Future Faculty Fellow at Cornell University in
Ithaca, New York. Prior to coming to PRI and Cornell, he was a Gaylord Donnelley Environmental
Fellow at Yale University. His innovative and cross-disciplinary research in ecology, paleontology,
and conservation biology has been published in the leading peer-reviewed journals in science andenvironmental studies, as well as in popular magazines. His current research emphasis centerson efforts in the emerging field of conservation paleobiology, which applies paleontological data,
theories and methods to understand and solve conservation problems.
Abstract: Conservation biology meets sclerochronology
Conservation paleobiology is a rapidly expanding discipline of conservation science that applies
the theories and analytical tools of paleontology to conserve and restore biodiversity and ecosystemservices. Sclerochronological records archived in the skeletal remains of organisms with accretionary
growth are currently underutilized in the field. In this presentation I will focus on selected casestudies that highlight the potential of sclerochronological records to give voice to a variety of pastsignals of change, which are as relevant to the many concerns, needs, and goals of conservation
biology today as they are in navigating an uncertain, rapidly changing future. My overall goal
is to raise awareness of the many opportunities that exist for closer collaboration between
sclerochronologists and conservation paleobiologists. I will also offer practical advice to thosewishing to develop conservation-relevant sclerochronological science.

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Session 7. Fisheries Ecology and Management
Dr. John MorrongielloSchool of BioSciences, University of Melbourne, Melbourne, VIC, Australia

Biography:

Dr. John Morrongiello is a Lecturer in the School of BioSciences at the University of Melbourne (Australia).
He holds a B.A./B.S. with Honors in Marine Ecology and Physical Geography from the University of
Melbourne and obtained a Ph.D. in Zoology and Animal Biology at Monash University (Australia). After
his PhD, Dr. Morrongiello completed a post-doc with CSIRO in Hobart, Australia where he worked with Dr
Ron Thresher exploring the impacts of climate change and fisheries on marine productivity using otolithbased growth histories. Following this, he briefly worked as research scientist in freshwater ecology with theVictorian State Government before commencing his lectureship at Melbourne. Dr. Morrongiello works inmarine and freshwater systems investigating how aquatic organisms, primarily fish, respond to environmental
change on contemporary and evolutionary time scales using field-based and experimental techniques. He
is also interested in the impacts of, and adaptations to, natural and human-induced flow variability, fishery
activity, and climate change. He has an active research interest in the development of statistical methods
and interpretation of data from biological hard-parts, primarily otoliths. Dr. Morrongiello uses this insightto provide a valuable long-term perspective to the causes and consequences of biological change in aquatic
environments, ranging from individuals to assemblages.

Abstract: Otoliths: From individuals to assemblages in a changing world

Growth is a fundamental biological process, driven by a multitude of intrinsic (within-individual) andextrinsic (environmental) factors, which underpins individual fitness, population demographics, andassemblage productivity. Growth is not only responsive to ecological factors such as resource availability
and environmental conditions, but is also a trait under contemporary evolutionary selection. Fish growth istherefore an ideal metric with which to study the impacts of natural and anthropogenic environmental change
across all levels of biological organisation.
Otoliths provide fish ecologists and fisheries managers with an enviable source of biological data. Whilst
we have long taken advantage of the periodically formed increments within otoliths to provide an estimateof fish age that can be readily used in stock assessment models, it is only more recently that we have begun
to interpret the growth information that these increments represent. These aquatic biochronologies haveenabled researchers to ask questions at daily to centennial time scales, in lakes to reefs to across large marine
ecosystems, providing valuable ecological insight to fisheries ecology and management.
Here, I will discuss my recent work investigating the eco-evolutionary drivers of fish growth using
information naturally archived in otoliths. I will highlight how this data can be used to explore a hierarchy ofgrowth variation, ranging from within- and among-individual responses to temperature and fishing selectivity,
to species-wide and assemblage-level assessments of fisheries, climatic, and oceanographic impacts. I will
also present examples of how age information can readily be used to recreate recruitment indices and indata poor fisheries. Throughout, I will make reference to statistical models that facilitate the extraction andinterpretation of biological insight from hardparts. I will finish by exploring exciting opportunities for theuse of otolith-derived growth information, including the estimation of age at maturity and the developmentof improved predictions of fisheries productivity. Otoliths have, and will continue to play, a vital role infurthering our ecological and evolutionary understanding of aquatic systems, and thus the management of ourmarine and freshwater resources.

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Coastal Maine, USA24

5th-9th June, 2016 • Portland, Maine, USA

Abstracts25

4th International Sclerochronology Conference, ISC 201626

Peaks Island, Maine, USA5th-9th June, 2016 • Portland, Maine, USA

Reconstructing Holocene temporal hydrographic variability
in Scottish Shelf Seas using dog cockle shells (Glycymeris
glycymeris)
Stella J. Alexandroff1*, James D. Scourse1, Paul G. Butler1, Bernd R. Schöne2
Bangor University, Bangor, Wales, UK, 2Institute of Geosciences, University of Mainz, Mainz, Gemany1*corresponding author: stella.alexandroff@gmail.com

The long-lived (>190 years) bivalve Glycymeris glycymeris is an annually resolved palaeoclimate
archive for the eastern North Atlantic and adjacent shelf seas. G. glycymeris sclerochronologies
have already been published for the Inner Hebrides, Scotland, and the Irish Sea, as well as otherareas. The aim of this study is to detect a signal of Atlantic hydrographic variability in Scottish
Shelf Seas that is as far as possible uncontaminated by other influences. In May 2014, we collecteddead valves and young live specimens of G. glycymeris from St Kilda, Outer Hebrides, Scotland.
This area is of particular interest as it is close to the Scottish shelf margin, has negligible freshwater
input and is thought to represent open-ocean North Atlantic signals well. We here present two
floating chronologies, each spanning >200 years, built from dead-collected G. glycymeris shells
from St. Kilda. All the shells in these chronologies were assigned radiocarbon ages between 37003300 cal yr BP. The radiocarbon ages confirm our findings by grouping the shells into two distinct
age bands consistent with our two floating chronologies. This archive provides the potential tocompare hydrographic conditions between the present and earlier in the Holocene. We present subannual δ18O data of these floating chronologies as well as of modern specimens from St. Kilda andinstrumental data to compare changes in mean state and seasonality between the present and thefourth millennium BP.

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4th International Sclerochronology Conference, ISC 2016

Archaeological applications of molluscan nitrogen isotope
analyses
Fred Andrus1*, Taylor Payne1, Heather Black2
University of Alabama, Tuscaloosa, AL, USA, 2Florida International Univsersity, Miami, FL, USA1*corresponding author: fandrus@ua.edu

Measurements of nitrogen isotopes (δ15N) in the organic fraction of mollusk shells are increasingly
used to assess temporal change in ecosystems related to anthropogenic impacts. The relative
durability of molluscan organic matter preserved in archaeological middens permits analysis of
δ15N over longer time periods, however applications have been few. In part this is due to uncertainty
concerning the effects of diagenesis and/or cooking on shell organic matrices and their nitrogenisotope records. Perhaps more significantly however, archaeologists are not familiar with this new
tool, therefore its application to anthropologically-relevant questions have not been extensively
explored. This presentation will describe the current state of knowledge regarding the impact of
cooking and post-depositional processes on shell δ15N records and describe some key questions
that remain. Additionally, published and new δ15N data measured in modern and ancient shellsof eastern oysters (Crassostrea virginica) and quohog clams (Mercenaria spp.) will be compared
between environments with different natural and human histories. These environments will range
from the densely populated upper Chesapeake Bay region to the less developed northern Gulf of
Mexico estuaries, and span the past 3000 years or more. Additionally, the potential utility of longlived Unionid mussels as archives of δ15N data in differing freshwater habitats will be compared todetermine the likelihood of reconstructing anthropogenic impacts near interior archaeological sites.
These data collectively suggest that even though shell organic material may be lost rapidly after
deposition, the human impact to nitrogen loading in coastal ecosystems was detectable as early as
pre-industrial historical time periods in some locales. This method may be developed to become auseful tool to aid understanding human population dynamics and economic activity over time.

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Environmental factors driving the valve gape activity of thebivalve Arctica islandica in Northern Norway
Irene Ballesta-Artero1*, Rob Witbaard1, Michael Carroll2, Jaap van der Meer1
Netherlands Institute for Sea Research (NIOZ), Texel, Netherlands, 2Akvaplan-niva, Tromsø, Norway

1*corresponding author: irene.ballesta.artero@nioz.nl

The bivalve Arctica islandica (Linnaeus 1767), also known as the ocean quahog, is the longestlived non-colonial animal known at present. It inhabits coastal waters in the North Atlantic andits annual shell increments are widely used for paleoclimatic reconstructions. However, there isno consensus about the intra-annual timing of growth and length of the period over which growthincrement formation takes place. Our research aims to identify the main environmental driversof A. islandica activity patterns, in order to clarify the ambiguity surrounding its growth and tounderstand the seasonality of signals enclosed within the carbonate shell. A lander was deployedon the sea bottom at Ingøya in Northern Norway containing 16 living Arctica islandica specimens
in individual containers. Each individual was wired with an electrode unit that measured gaping
activity (distance between electrodes mounted on both valves) every minute. The lander was also
equipped with instruments to simultaneously monitor environmental conditions (Temperature,
Salinity, Chlorophyll-a, Turbidity, and Light conditions) and coincident with the valve gape activity.
The seasonal activity of these bivalves were examined between February 2014 and September 2015.
There were clear seasonal patterns of valve gape activity, with average values from 0.2 to 0.8. The
population was inactive between October and January (valve gape <0.2). The main driver of thispopulation activity appeared to be food availability (measured as Chlorophyll-a). This experimental
setup provided insight into the variability of A. islandica activity patterns between individuals andover the seasons, key factors for paleoclimatic reconstructions.

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4th International Sclerochronology Conference, ISC 2016

Development of a species-specific oxygen isotope transfer
function for Arctica islandica shells: Insights from atemperature experiment
Jared Ballew1*, Alan Wanamaker1
Iowa State University, Ames, IA, USA1*corresponding author: jbballew@iastate.edu

The geochemistry of aragonite shells of Arctica islandica, a long-lived marine bivalve native to theNorth Atlantic, is widely used as a proxy to reconstruct past marine conditions. Specifically, theoxygen isotope (δ18O) composition of the shell can be used to estimate hydrographic conditions,however like all biocarbonates the δ18O of shell material is influenced by seawater temperatureand the isotopic composition of seawater (δ18Owater - related to salinity). Although several
paleotemperature transfer functions have been developed for aragonitic taxa (e.g., Grossman andKu, 1986), some of these functions have somewhat large errors (> ± 1 °C) and there can be fairly
large differences in predicted temperatures (with identical shell and water isotope values) among
these different paleotemperature equations. Despite its paleoceanographic potential, to date no
species-specific transfer function has been developed to translate the δ18O of the shell material
to seawater temperature for A. islandica. In this study, we sought to develop a species-specifictransfer function for A. islandica, which may potentially reduce the errors associated with seawatertemperature reconstructions, and to further evaluate if the shells grew in oxygen isotopic equilibriumwith ambient seawater. A total of 30 juvenile A. islandica clams (~3 yr. old; average shell heightof 40 mm) were grown under temperature-controlled conditions during a 16-week period fromMarch 27 to July 21, 2011. Seawater from the Darling Marine Center in Walpole, Maine, USA was
pumped into temperature and flow controlled tanks that were exposed to ambient food and salinity
conditions. Clams were grown at 10.3 ± 0.3 °C for six weeks and then at 15.0 ± 0.4 °C for an
additional 9.5 weeks. Prior to the experiment, the clams were stained with calcein (a commonly usedbiomarker) and again when the temperature was changed from 10 to 15 °C. Salinity was monitored
hourly, with average salinity values of 30.2 ± 0.7 and 30.7 ±0.7 for the first and second phases of theexperiment, respectively. Water samples were taken approximately every two weeks to establish the
δ18O values of seawater. The average shell growth during the first phase of the experiment was 2.4
mm with a linear extension rate of 0.40 mm/week. The average shell growth during the second phaseof the experiment was 3.2 mm with an extension rate of 0.34 mm/week. After the culture period,
shell samples from the distinct temperature regimes were micromilled and measured for δ18O. A
previously developed salinity/oxygen isotope mixing line was used to model daily δ18O values ofthe seawater, and verified with actual seawater samples. Considering analytical and instrumental
uncertainties, preliminary results suggest that A. islandica precipitates its aragonitic shell in oxygenisotopic equilibrium seawater. Additional shell material, including adult individuals, will be analyzed
in the near future to refine this preliminary paleotemperature transfer function for A. islandica.

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Clams and climate: Implications for reconstructing
paleoseasonality in southern Alaska
Christine Bassett1*, Fred T. Andrus1, Catherine F. West2, Michael A. Etnier3,
University of Alabama, Tuscaloosa, AL, USA, 3Boston University, Boston, MA, USA, 5Portland State University,
Portland, OR, USA1*corresponding author: cbassett@crimson.ua.edu

The archaeological record reflects fluctuating marine conditions from the Aleutian Islands to theNorthwest Coast of North America during the Late Holocene. Though not widely tested, recent
research suggests that conditions may have cooled enough during the Late Holocene to allow
seasonal ice to accumulate as far south as Aleutian Islands. Zooarchaeological analysis supporting
this claim relies on the presence of pagophylic mammalian remains in archaeological sites from
Unalaska Island. However, disentangling behavioral changes from humans and the animals theyhunt proves difficult in this case. Sclerochronological analysis of biogenic carbonates can provide
additional paleoenvironmental information. Oxygen isotope analysis of bivalve shell yields
information on the temperature of the water in which the organism grew. However, in coastal
environments, variations in δ18O of water may complicate the interpretation of shell isotope profiles.
Measuring and comparing the length of seasonal shell growth in select species of bivalves may
complement isotopic analysis, together providing a more precise paleoclimate reconstruction. This
research utilizes the regular growth of Saxidomus gigantea, abundant both on modern and ancient
coastlines, to provide information about the length of its growing season, which is temperaturedependent. Modern samples of S. gigantea were collected from Alaska (n=20) and British Columbia(n=10) and the length of their respective growing seasons were measured by counting the numberof lunar-daily growth increments (LDGI) imaged on acetate peels between consecutive isotopically
identified periods of winter growth may indicate changes in seasonality in S. gigantea. Shells
collected from Alaska exhibited shorter growing seasons than those collected in British Columbia.
This method was then applied to five S. gigantea shells from four archaeological sites, Karluk(n=2) Rice Ridge (n=1), Settlement Point (n=1), and Uyak (n=1), to determine if the same methods
are applicable to ancient shells. Preliminary results indicate that this method does work on ancient
shells. Future analysis may potentially provide reconstructions of changes in seasonality in ancient
shells abundant throughout Alaska’s archaeological record and consequently confirm or refutefindings from previous faunal analysis on Unalaska.

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4th International Sclerochronology Conference, ISC 2016

Crossdating and preservation of signal strength in growthincrement chronologies
Bryan Black1*, Peter van der Sleen1
University of Texas at Austin, Marine Science Institute, Port Aransas, TX, USA1*corresponding author: bryan.black@utexas.edu

Proxies from the hard parts of fish, bivalves, corals, and trees are critical to establishing climategrowth relationships, identify linkages within and across ecosystems, reconstruct climate, andestimate population age structures. However, dating controls are necessary to ensure temporal
precision and accuracy; simple counts cannot ensure that all layers are placed correctly in time.
Originally developed for tree-ring data, crossdating is the only such procedure that ensures all
increments have been assigned the correct calendar year of formation. In a simulation exercise,
growth-increment data from two tree species, two marine bivalve species, and a marine fish species
are used to illustrate sensitivity of environmental signals to modest dating error rates. When falsely
added or missed increments are induced at one and five percent rates, errors propagate back throughtime and eliminate high-frequency variability, climate signals, and evidence of extreme events
while incorrectly dating and distorting major disturbances or other low-frequency processes. These
consecutive Monte Carlo experiments show that inaccuracies begin to accumulate in as little as two
decades, though consequences may be even greater in real-world scenarios. We stress that, wherever
possible, the fundamental tenets of crossdating must be applied to fully resolve environmental
signals. Situations in which crossdating may not be readily applied are also addressed, as could be
the case in sample sets with extremely low levels of interannual growth variability, limited sample
replication, or short-lived species.

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A 388-year Arctica islandica shell-based chronology from theFaroese Shelf: Implications for a better understanding of thenatural climate variability of the Faroe Current
FabianBonitz1*, Carin Andersson1, Tamara Trofimova1
1

Uni Research Climate, Bjerknes Centre for Climate Research, Bergen, Norway*corresponding author: fabian.bonitz@uni.no

In this study we aim to investigate the natural marine climate variability of the Faroe Current bybuilding and analyzing a multi-centennial chronology from shells of the bivalve species Arctica
islandica from the Faroese Shelf. The Faroe Current is one of the main inflow branches of warmer
water masses into Northern Europe and the Arctic and is therefore of great importance for the
climate development in these regions. The area around the Faroe Islands is an excellent study area
because it is located in the middle of the Faroe Current and terrestrial and coastal interferenceis small. Since the species A. islandica is forming annual growth increments, its shells provide
information of climate conditions on an annual scale. Here we present the first multi-centennial
absolutely dated chronology from the Faroese Shelf covering the time period from 2013 – 1625
and discuss its potential for providing a reliable annually resolved paleo record in the this area.
The chronology derives from shell material from the eastern side of the Faroe Islands from around
100 meter water depth and consists of 4 live-collected, 12 articulate and 18 sub-fossil specimens.
All specimens cross-match well and radiocarbon dating of the sub-fossil specimens confirms theirplace in the chronology. The good cross-matching shows that the specimens share a common
signal of an external forcing and that molluscan sclerochronological studies can be applied on the
Faroese Shelf. The standardized growth indices of the chronology moderately anti-correlate with
April – August sea-surface and air temperatures from this area for the last 100 years that indicatesfavorable conditions for growth when temperatures are lower. A comparison of the standardized
growth indices with primary productivity data from the Faroese Shelf shows a strong positive
relationship meaning that higher primary productivity rates result in wider growth increments. Since
the main primary production event takes place in spring and summer the main growing season in
A. islandica shells from the Faroese Shelf most likely occurs during this time. This is supported byseveral δ18O measurements from the growth increments of the years 2013 – 2001 as the δ18O-based
temperature reconstructions from these growth increments correlate best with spring and summer
sea surface temperatures. Moderate correlations between the standardized growth indices and multidecadal oscillations such as NAO and AMO can also be found especially for the last 100 years. In
conclusion, our results suggest that the growth increments in A. islandica from the Faroese Shelf
reflect changes in primary productivity and temperatures and also that the shells capture longterm signals. Further, δ18O measurements in the shells lead to robust results and can potentially be
used for temperature reconstructions for time periods beyond instrumental observations. Thus ourchronology has the potential to contribute to a better understanding of the natural climate variabilityof the Faroe Current.

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4th International Sclerochronology Conference, ISC 2016

Temperature reconstructions based on δ18O measurements inbivalve shells from the Faroese Shelf
Fabian Bonitz1*, Carin Andersson1, Tamara Trofimova1
Uni Research Climate, Bjerknes Centre for Climate Research, Bergen, Norway

1*corresponding author: fabian.bonitz@uni.no

Annually resolved temperature records before instrumental observations are scarce in the marine
realm, especially at higher latitudes. The geochemical analysis of growth increments in bivalve
shells have the potential to close this gap and to provide past sea-surface temperature reconstructions
on an annual time scale. In this study, we investigate the oxygen isotopic composition in annuallyformed growth increments in the bivalve species Arctica islandica and apply δ18O-based paleothermometry. The analyzed shell material was collected east of the Faroe Islands from water depthsof around 100m in 2014. The samples for the δ18O analysis were extracted from 2 live-collected
shells by micro-drilling. Depending on the size of the growth increment, between 4 and 10 samples
were collected from every growth increment from 2002 – 2013. The reconstructed temperatures
based on the δ18O values range from about 6°C to 10°C in a single growth increment with lower
temperatures at the beginning of the growth increment and higher temperatures towards the endof the growth increment. This indicates that a seasonal temperature signal is preserved in the δ18O
composition of the growth increments. Further, the reconstructed temperatures correlate best withobserved sea-surface temperatures from around April to July. This is in agreement with the main
growing season of phytoplankton on the Faroese Shelf and suggests elevated primary productivity to
be one of the most important driving factors for the shell growth in A. islandica. The analysis of δ18O
values in the growth increments and the comparison with instrumental temperature data show thatthe bivalve species A. islandica captures the spring/summer temperature signal in its oxygen isotopic
composition and has the potential to be used for time periods prior instrumental observations.

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5th-9th June, 2016 • Portland, Maine, USA

Isotope sclerochronology and hunter-gatherer seasonality:
Archaeological landscapes from the Pacific and Atlantic coastsof Canada
Meghan Burchell1*, Aubrey Cannon2, Matthew Betts3, Bernd R. Schöne4
Memorial University, St. John’s, NL, Canada, 2McMaster University, Hamilton, ON, Canada, 3Canadian Museum ofHistory, Gatineau, QC, Canada, 4University of Mainz, Mainz, Germany
1*corresponding author: mburchell@mun.ca

Stable oxygen isotope (δ18O) analysis of shell has been a component of understanding seasonalpatterns of hunter-gatherer shellfish harvesting for almost 40 years, but only recently havearchaeologists begun to use more sophisticated methods to derive seasonality estimates. The
integration of high-resolution δ18Oshell data with macro-growth features and fortnightly/lunar daily
growth increments (F/LDGI) permits a precise seasonality estimate that can control for the opposing
effects of temperature and salinity. This is critical for shell seasonality estimates from archaeologicalsites, since the majority of archaeological sites are in close proximity to seasonal freshwater sourcesthat contribute to sub-annual fluctuations in temperature salinity.
This paper explores three case studies in Canadian archaeology from the Pacific and Atlantic
coasts of Canada from ~4000 years BP to the 18th century with an emphasis on coastal British
Columbia, Nova Scotia and Newfoundland. We argue that the analytical scale used to derive
δ18Oshell must ensure the precision of the seasonality estimate, while also considering the cultural,
historical and temporal contingencies that shaped hunter-fisher-gatherer landscapes. In all threestudies, both live-collected and archaeological specimens were micro-milled in 100-micron steps
at the ventral margin to obtain δ18Oshell values that were aligned to either F/LDGI or macrogrowth structures. The study of Saxidomus gigantea from British Columbia provides an exemplarymodel of a regional and temporal scale study in seasonality through the alignment of F/LDGI with
δ18Oshell from 139 individual shells from nine shell midden sites. These sites, consisting of camps,
villages and specialized shellfish camps are located in the traditional territory of the Heiltsuk First
Nation, spanning over 4000 years. Moving east, Mya arenaria from Nova Scotia were analyzed
from two sites in the traditional territory of the Mi’kmaq, dating from 1500 - 400 years BP.
From Newfoundland, the analysis of Mytilus edulis from a 16th - 18th century Inuit winter sod
house informed the interpretation of the seasonal range of landscape use. Coincidentally, in all
three studies, the seasonal emphasis on shellfish harvesting falls in the spring and autumn. Whileunderstanding the spectrum of seasonal subsistence and settlement activities of a site cannot be
achieved from shell analysis alone, the incorporation of shell seasonality data challenges notions
about site use, and contributes to a nuanced understanding of subsistence and settlement patterns.
The three studies illustrate how the precision of high-resolution sampling for δ18O is negotiatedwith the number of individual shell samples to develop meaningful interpretations of past landscapeuse, site function, and seasonal patterns of shellfish harvest while further understanding the role ofshellfish in hunter-fisher-gatherer societies.

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4th International Sclerochronology Conference, ISC 2016

The regulatory context of the use of biochronologies forbaseline environmental monitoring
Paul Butler1*, Juliane Steinhardt2
Bangor University, Bangor, Wales, UK, 2Hartley Anderson LTD, Aberdeen, Scotland, UK

1*corresponding author: p.g.butler@bangor.ac.uk

The commercial application of sclerochronological techniques to environmental monitoringis intimately related to the regulatory framework, since such monitoring does not in itself add
economic value to the final product. In turn, approaches to environmental regulation assume or
propose particular desirable states, in the past, present or future, that are to be sustained or targeted.
The goal of marine environmental monitoring in the commercial sector is the assessment of theextent to which these states are achieved in the contexts of (i) the impact of individual marine
infrastructure developments and (ii) the integrated impact of all human activity in the marine
environment. The unique selling point of sclerochronology is its potential for the reconstructionof long baselines of environmental variables and hence for the ability to compare pre- and postindustrial conditions. However, the identification of indicators of the pre-industrial condition of
the environment does not in itself define a “pristine” environment that can be targeted for theachievement of “good” environmental status (in the context of the European Union’s Marine
Strategy Framework Directive). More realistically, the definition of such a status will require theidentification of some acceptable degree of variability in the ecosystem response. It is this degree ofvariability that can be assessed with the help of biochronologies drawn from multiple sources (egbivalve molluscs, fish otoliths, corals). Here, we will discuss the regulatory frameworks in whichmarine biochronologies can function as environmental monitors, especially those contexts related tobaseline environmental monitoring and the concept of good environmental status.

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5th-9th June, 2016 • Portland, Maine, USA

Shell growth and environmental control of methane-associatedThyasirid bivalves from Svalbard cold seeps
Michael Carroll1*, Emmelie Åström2, William Ambrose3, William Locke4, Graham
Oliver5, Wei-Li Hong6, JoLynn Carroll6
Akvaplan-niva, Tromsø, Norway, 2University of Tromsø, Tromsø, Norway, 3Bates College, Lewiston, ME, USA, 4Bates
College, Lewiston, Maine, 5National Museum of Wales, Cardiff, Wales, UK, 6CAGE - University of Tromsø, Tromsø,
Norway1*corresponding author: mc@akvaplan.niva.no

The analysis of molluscan shell material (sclerochronology) can provide information about anorganism’s age, growth history, and environmental conditions during its lifetime. Bivalve molluscs
are common members of hydrothermal vents and methane cold seeps communities where, supported
by chemosynthetic symbionts, they can reach high density and biomass. But little is known about
methane-associated bivalve populations inhabiting high Arctic cold seeps, and sclerochronologicalanalysis of methane-influenced bivalves is rare. We measured growth rates and chemical and isotopic
shell signatures in a newly discovered species of bivalve (Thyasiridae) from cold seeps at 350-390m
depth southwest of Svalbard. First discovered in 2014, shells of Thyasira capitanea sp.nov. were
found at 2 seep systems in Storfjordrenna. Mean shell carbon isotopic ratios from inorganic δ13C(-4.8‰) and organic δ13C (-26.9‰) fractions indicate a methane influenced habitat and food source.
Shell mineral ratios sampled along the axis of growth with laser-ablated ICP-MS exhibit variability
through time and between sites, suggesting that concentrations of these elements that are affectedby methane emissions. The mineralogical data also elucidates the internal pattern of shell deposition
and growth checks, and combined with the isotopic and growth rate data, enables us to interpret thetemporal history of methane release from these locations.

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4th International Sclerochronology Conference, ISC 2016

Recent decline in skeletal density and calcification rates ofsubarctic crustose coralline algae
Phoebe Chan1*, Jochen Halfar1, Walter Adey2, Phillip Lebednik3, Robert Steneck4,
Chris Norley5, David Holdsworth5
University of Toronto, Mississauga, ON, Canada, 2Smithsonian National Museum of Natural History, Washington DC,
USA, 3Lebcon Environmental Services, San Francisco, CA, USA, 4Darling Marine Center, Walpole, ME, USA, 5Western
University, London, ON, Canada
1*corresponding author: phoebetw.chan@utoronto.ca

Warming surface ocean temperatures combined with the continued invasion of atmospheric CO2 into seawater
are increasing physiological stresses on calcareous marine organisms. Ocean acidification has been shownto have detrimental impacts on marine carbonate organisms in tropical and temperate localities. However,greater oceanic CO2 uptake in higher latitudes suggests that calcareous organisms in the Arctic and Subarctic
are even more susceptible to acidifying conditions than those residing in lower latitudes. This is especiallytrue for coralline algae Clathromorphum, a dominant calcifier in Arctic/Subarctic hard-bottom communities
that build their skeletons using high Mg-calcite, which is even more soluble than aragonite in corals. Here
we present an annually-resolved growth, density, and calcification rate record from crustose coralline alga
Clathromorphum collected from the Subarctic North Pacific, a region that has undergone a long-term declineof 0.08 ± 0.01 pH units since the late 19th century.
Coralline algal calcification rates display distinct multidecadal variability that is inversely related to the
Arctic Oscillation Index (AO). Alternations between positive (negative) AO phases are closely linked withstrengthening (weakening) of the Northern Hemisphere polar vortex, which regulates the frequency andintensity of storm events. During the positive AO phase, anomalously low pressure dominates the Polarregions, steering clouds and stormy weather northward. This induces wind mixing and upwelling, increasing
surface water production (which intercepts solar insolation available for coralline algal photosynthesis),
thereby resulting in reduced algal growth and calcification rates.
In contrast, while algal skeletal density also shows pronounced multidecadal variability, values have enteredan unprecedented decline since 1980. The ecological benefits of sustained vertical growth in coralline
algae may allow organisms to quickly heal and regenerate skeletal/thallus mass from damaging disturbance
events such as wave action and herbivore grazing, both of which are common features of the Aleutian Island
nearshore ecosystem. However, the metabolic trade-offs associated with maintaining algal calcification
through continued growth may have translated into the production of weaker (less dense) skeletons resulting
in a loss in structural integrity, and increasing susceptibility to erosional processes.
Diminishing algal density may also be associated to temperature stress resulting from increasing regional sea
surface temperatures (SST) recorded in the Aleutian Island region. Regression analysis between algal density
and Hadley Centre SST 1° x 1° reconstruction (HadISST) indicates a strong negative relationship, such that
coralline algal skeletal density increases (decreases) with cooler (warmer) SST. While the exact mechanisms
responsible for the here observed declines in algal growth parameters are uncertain, our study reveals that inaddition to acidification, sunlight availability and temperature stress may also be factors that influence theability of corallines to calcify.

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5th-9th June, 2016 • Portland, Maine, USA39

4th International Sclerochronology Conference, ISC 2016

Diet of fossil and modern bivalves and gastropods revealed bycarbon and nitrogen isotopes of shell-associated organic matter
Shibajyoti Das1*, Christopher K. Junium1, Linda C. Ivany1
Syracuse University, Syracuse, NY, USA1*corresponding author: sdas100@syr.edu

The carbon and nitrogen isotopic compositions of an organism’s tissues are representative of its
diet (DeNiro and Epstein, 1978; DeNiro and Epstein, 1981). Hence, stable isotopic analysis has
become a powerful tool to determine the diets of organisms with poorly understood ecologies(Peterson and Fry 1987; Hentschel 1998; Vander Zanden and Rasmussen 1999). This approach has
been extended to the fossil record in a few cases (Ostrom et al., 1993), but the potential exists for agood deal more clarity on the diets of fossil animals and trophic relations among them. Preservationof organic matter from the extracellular matrix is possible in the shells of fossil mollusks, andthis material can be used for stable isotopic analysis. Here we explore variation in the carbon andnitrogen isotopic composition of shell organic matter for several bivalve and gastropod taxa, bothmodern and fossil. Because organisms are known to change their feeding behavior over ontogeny,
we will use sclerochronological techniques to assess both taxonomic and ontogenetic variation in
the isotopic composition of shell organic matter. We test this approach on modern and Pliocene
suspension-feeding bivalves and carnivorous gastropods. The techniques developed for these more
recent materials will be applied to the reconstruction of ancient trophic strategies and ultimately
food web reconstruction using specimens from the Late Cretaceous (Campanian/Maastrichtian)Lopez de Bertodano Formation exposed on the Antarctic Peninsula. Specimens were obtained
from the Zinsmeister Collection housed at the Paleontological Research Institution in Ithaca, NY.
The collection comprises of a broad group of near-shore organisms including bivalves, gastropods,
ammonites, corals and calcareous worms, all co-occurring at one of several individual collection
localities. The long-term goal of this project is to apply these techniques to examine how marine
communities respond to significant environmental perturbations such as Oceanic Anoxic Events or
the Paleocene-Eocene Thermal Maximum.

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5th-9th June, 2016 • Portland, Maine, USA

Salinity shifts in the southwest tropical Pacific from the Little
Ice Age to the 20th century
Kristine DeLong1*, Terrence Quinn2, Chuan-Chou Shen3, Frederick Taylor2
Louisiana State University, Baton Rouge, LA, USA, 2Institute for Geophysics, Jackson School of Geosciences, Universityof Texas at Austin, Austin, TX, USA, 3Department of Geosciences, National Taiwan University, Taipei, Taiwan, 4Institutefor Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, TX, USA1*corresponding author: kdelong@lsu.edu

During the Little Ice Age, South Pacific SSTs were, on average, 1ºC colder than the 20th century
with evidence of more saline surface waters in the southwest tropical Pacific from low-resolution
coral δ18O and Sr/Ca records. Here we present monthly-resolved coral δ18O and Sr/Ca determinations
from Porites lutea colonies offshore of Amédée Island, New Caledonia (22º28.8ʹS, 166º27.9ʹE)in the southwest tropical Pacific to investigate shifts in SST and sea surface salinity (SSS) from1649 to 1999 CE. Coral Sr/Ca is a function of SST and coral δ18O varies with SST and the δ18Oof seawater (δ18Osw), which reflects changes in SSS, such that paired analysis of these two proxies
allows us to quantify SSS shifts. Coral δ18O variations from 1649 to 1900 CE contain interannual tobidecadal variations larger than those observed from 1900 to 1999 CE and in the coral Sr/Ca-SST
reconstruction, suggesting large SSS shifts on those time scales. The coral Sr/Ca-SST reconstruction
co-varies with the South Pacific Decadal Oscillation, for which SST anomalies in the southwest
Pacific are linked to precipitation anomalies in the western equatorial Pacific. Furthermore, thisdecadal-scale SST variability changed in periodicity and strength before 1893 CE, suggesting a shift
in natural SST variability for this location. Comparison of coral δ18O-SST and Sr/Ca-SST anomalies
reveals a persistent +0.3‰ divergence in coral δ18O or an ~0.8 psu shift to saltier SSS prior to ~1900
CE in which relatively 18O-rich surface waters are present as the result of more evaporation than
precipitation. The shift to saltier conditions coincides with the shift in coral Sr/Ca-SST decadal
periodicity and strength suggesting a change in oceanic-atmospheric processes in the southwest
tropical Pacific during the transition from the Little Ice Age to anthropogenic warming in the 20th
century.

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4th International Sclerochronology Conference, ISC 2016

Save our Marine Annually Resolved Proxy Archives (MARPA)!
Kristine DeLong1*, Emilie Dassié2, Kelly Hali Kilbourne3, Branwen Williams4
Louisiana State University, Baton Rouge, LA, USA, 2Université Pierre et Marie Curie, Paris, France, 3University of
Maryland Center for Environmental Science, Cambridge, MD, USA, 4Claremont McKenna-Pitzer-Scripps Colleges,
Claremont, CA, USA1*corresponding author: kdelong@lsu.edu

Funding agencies, such as the National Science Foundation (NSF), require detailed DataManagement Plans (DMP) for proposals that include plans for archiving data and physical samples
yet there is no guidance on what is acceptable for a given community. Several groups are working on
improving platforms for sharing data (NOAA Paleoclimate, Pangaea, EarthCube, and Linked Earth);
however, no efforts are being made for curation of physical samples for our community. This is thetime for the Sclerochronology community to join this initiative and to work on defining the standards
needed for our field in order to curate physical samples, data derived from those physical samples,and metadata from both to promote the expansion of research while giving the original researchers
credit and recognition for their work. Marine Annually Resolved Proxy Archives (MARPA) is
a grass roots effort created under the EarthCube umbrella (http://earthcube.org) that is currently
working on recommendations for physical samples to include in DMPs by identifying current
resources that can be used by researchers.
There are several resources for curating physical samples currently in place that the MARPA
working group reviewed. The System for Earth Sample Registration (SESAR; http://www.
geosamples.org/) is a NSF-funded cyberinfrastructure that provides a registry for physical samples
with their metadata. SESAR offers tools and services for users to manage their physical sample
metadata and obtain International Geo Sample Numbers (IGSN; www.igsn.org) for citationof physical samples. The IGSN was developed by SESAR and has become an internationallyrecognized standard for sample identification. Several publishers, including AGU journals andPalaeogeography, Palaeoclimatology, Palaeoecology (Elsevier), are now requiring the use of IGSN
in their publications. The MARPA working group is developing a web site (marpasite.wordpress.
com/) with pertinent information for the community including a tutorial for entering physical sample
metadata in SESAR, sample DMPs for proposals and grant reports, and our white paper reviewing ofphysical sample curation and geochemical data with recommendations. Additionally, we are seeking
feedback on a template for data sharing for the sclerochronology community, likely in Excel format,
complete with standardized vocabulary that could be stored locally offline with each researcher
before submitting to a permanent repository (NOAA Paleoclimate and/or Pangaea). This effort will
help the Sclerochronology community share their data with the wider community for data synthesis
projects, such as Oceans2K and Iso2K, while receiving credit for their work.

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5th-9th June, 2016 • Portland, Maine, USA

Conservation paleobiology meets sclerochronology
Greg Dietl1*
Paleontological Research Institution, Ithaca, NY, USA1*corresponding author: gpd3@cornell.edu

Conservation paleobiology is a rapidly expanding discipline of conservation science that applies
the theories and analytical tools of paleontology to conserve and restore biodiversity and ecosystemservices. Sclerochronological records archived in the skeletal remains of organisms with accretionary
growth are currently underutilized in the field. In this presentation I will focus on selected casestudies that highlight the potential of sclerochronological records to give voice to a variety of pastsignals of change, which are as relevant to the many concerns, needs, and goals of conservation
biology today as they are in navigating an uncertain, rapidly changing future. My overall goal
is to raise awareness of the many opportunities that exist for closer collaboration between
sclerochronologists and conservation paleobiologists. I will also offer practical advice to thosewishing to develop conservation-relevant sclerochronological science.

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4th International Sclerochronology Conference, ISC 2016

Testing the effect of climate warming on oyster life history
using geohistorical records
Stephen Durham1*, Gregory Dietl2
Cornell University, Ithaca, NY, USA, 2Paleontological Research Institution, Ithaca, NY, USA1*corresponding author: srd77@cornell.edu

The metabolic theory of ecology (MTE) proposes that variations in metabolic rate—which scaleswith an organism’s body mass and temperature—are responsible for many patterns in ecology,
including covariations in lifespan, body size, and temperature. If temperature and mass estimates
are available, predicting shifts in biological rates and times (e.g. lifespan) with temperature change
is possible, making MTE a potentially powerful tool for examining LH responses to climatechange in the fossil record. The MTE predicts that even modest increases in temperature (~1°C)
can reduce ectotherm lifespans by between 3% and 19%. To test this prediction, we collectedbody size and lifespan data for 3,110 and 1,207 oysters (Crassostrea virginica) from Pleistocene
fossil deposits and modern reef death assemblages, respectively, in South Carolina. Lifespans were
estimated using models based on sclerochemical analyses of 55 fossil and 49 Recent specimens. The
lithology, associated fauna, and information from the shells themselves (e.g., height-length ratios
and attachment scar lengths) suggest that the fossil and Recent environments are similar. However,amino acid racemization dating suggests that the Pleistocene oysters lived during marine isotope
stage 9 (MIS 9), when sea surface temperatures were ~2°C warmer and sea level was several meters
higher than today, making this an opportunity to compare LH of oysters living in different climates.
Our data show that the average size of the largest 50% of Pleistocene oysters was smaller than the
average size of the largest 50% of Recent oysters (t(5.97) = -2.36, p = 0.057). Growth models (powerfunctions) derived from the sclerochemical profiles were used to estimate size-at-age relationships
for all measured oysters, and analysis of the oldest 50% of Pleistocene and Recent oysters suggeststhat Pleistocene oysters were also shorter-lived than Recent oysters in South Carolina (t(5.5) = -1.94,
p=0.105). Finally, the slope of a plot of log average lifespan of Pleistocene and Recent oysters versus
inverse temperature (assuming an average temperature difference of 2°C) was 1.005—within the
MTE-predicted range of 0.2-1.2. Thus, the results are consistent with general expectations from
MTE and LH theory, suggesting that studying LH changes in the fossil record may yield useful
information for managing natural oyster populations in the coming decades as the climate warms.

44

5th-9th June, 2016 • Portland, Maine, USA

Evaluating the strength and temperature variability of
the North Atlantic Current for the second half of the last
millennium using an Arctica islandica-derived increment series
Juan Estrella-Martínez1*, Paul Butler1, James Scourse1, Christopher Richardson1,
Bernd Schöne2
Bangor University, School of Ocean Sciences, Menai Bridge, Wales, UK, 2University of Mainz, Mainz, Germany

1*corresponding author: oss417@bangor.ac.uk

Although they are important for planetary climate modulation, the high latitudes are not well
represented by high resolution palaeoceanography. Since the marine conditions in these latitudes
are unsuitable for the development of natural archives like corals and varved sediments, muchof the published literature consists of records with, at best, decadal resolution. The annuallydeposited increments of the mollusk Arctica islandica can help fill this void, allowing us to studyhydrographic conditions in greater detail. A strongly crossmatched increment series provides anabsolute (no uncertainty) age model on which to base geochemical results obtained from the analysisof shell material. We present an extension back to 1543 of a previously-published A. islandica shellchronology for the Fladen Ground in the northern North Sea. Because it is subject to inflow of North
Atlantic Current waters, this area is representative of the greater North Atlantic from the Labrador
Sea to the Faroe Islands. Based on modelled results, we relate the width of the growth increments
to the strength of the winter and spring inflow of North Atlantic waters into the North Sea throughthe Fair Isle Channel with a one-year lag from 1959 to 2001 (r = -0.41, p<0.01) which affects the
distribution of nutrients over the Fladen Ground. We use these results along with geochemical
analysis of shell material and publicly available 20th century oceanographic data to construct a local
δ18O-carbonate to temperature calibration and develop a continuous annual temperature record fromthe mid-19th century until 2003, which will later be extended for the full length of the chronology.
This reconstruction will be an excellent resource for climate model comparisons, enabling more
tightly constrained projections of future climate variability.

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4th International Sclerochronology Conference, ISC 2016

Multiproxy reconstruction of seawater temperature in the Bayof Brest using shells of dog cockles, Glycymeris glycymeris
Amy Featherstone1*, Melita Peharda2, Bernd Schöne3, Paul Butler4, Laurent Chauvaud1,
Julien Thébault1,
Université de Brest - CNRS, 29280 Plouzané, Brest, France, 2Institute of Oceanography and Fisheries, Split, Croatia,
Universität Mainz, Mainz, Germany, 4School of Ocean Sciences, College of Natural Sciences, Bangor University, Menai
Bridge, Wales, UK
13*corresponding author: amy.featherstone1@gmail.com

Since the end of the 20th century, global climate change has become a major focus of politicians
and scientists worldwide, the consensus being that human activities are influencing environmental
changes and affecting the Earth’s ecosystems. To establish the full extent of human influence,
it is therefore necessary to reliably differentiate between natural variations in climate andanthropogenic influences. In order to do this, we must build a record of past long-term naturalvariability in the environment. In recent years bivalve mollusc shells have been successfully usedas paleoenvironmental and paleoclimatic archives through the analysis of their growth increment
patterns and their geochemical composition. Glycymeris glycymeris is a bivalve found in coarsegrained subtidal sediments, with a wide distribution from Cape Verde to Norway. Thanks to its
remarkable longevity (up to 200 years in the northern part of its geographical distribution area),
it has a strong potential for building chronologies extending over several centuries, making it avaluable resource for long-term climate reconstructions in temperate settings.
Here, we developed a cross-dated chronology of over 30 years based on internal growth increments
in G. glycymeris specimens collected both live and dead from the Bay of Brest, Brittany, France. The
Standardised Growth Increment (SGI) chronology, developed from thirty-five individuals (averageage 20 years), was found to be statistically robust (Expressed Population Signal (EPS)>0.85).
In addition to growth increment analysis, eighteen specimens were investigated for their stable
isotope composition. Aragonite samples were micromilled in early ontogeny growth increments ofseveral specimens with overlapping lifespans, and subsequently analysed for their oxygen isotope
composition. The continuous time-series of oxygen isotope ratios was then compared to in situ
temperature and salinity data from the SOMLIT monitoring station, which was established in 1998,
in order to calibrate and build a localised paleotemperature equation. This specific equation was thenused to estimate sea surface temperatures in the Bay of Brest from 1969 to 2011.
Overall, this study demonstrates that G. glycymeris can be used for decadal scale, high-resolution,
reconstructions of past sea surface temperatures in the coastal waters of the Bay of Brest for periods
before the availability of instrumental measurements.

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5th-9th June, 2016 • Portland, Maine, USA

Paleobiology needs your help
Seth Finnegan1*
UC Berkeley, Berkeley, CA, USA1*corresponding author: sethf@berkeley.edu

The Phanerozoic marine fossil record presents many striking patterns that remain poorly understooddespite decades of study. Many long-term macroevolutionary and paleoecological trends are thought
to have been driven by organism-environment interactions, but understanding of these trends ishampered by lack of information about both the environments in which early animals evolved andthe metabolisms of these animals. Because they focus on the intersection of organismal growthand environment, sclerochronological studies have enormous potential to bring clarity to these andother paleobiological controversies. My agenda in attending this meeting is, first, to learn from thesclerochronology community, and second, to bring some outstanding problems to your attention. I
will focus on two broad problems, though there are many other areas in which sclerochronologicalstudies can contribute to our understanding of deep-time paleobiological patterns. Our knowledgeof deep-time climate changes comes primarily from the oxygen isotope record (δ18O) of biogenic
carbonates and phosphates. Classic studies by Veizer and colleagues established that the average
preserved δ18O values of tropical-subtropical shallow-water calcifiers rose by ~6‰ from theCambrian to the present. Taken as a record of sea surface temperatures this implies that early animals
routinely survived temperatures in excess of 50˚C. Alternative interpretations include pervasive
diagenetic alteration of ancient fossils and progressive δ18O enrichment of the marine oxygen
reservoir through time. The latter model is not supported by recent clumped isotope studies, butthese studies themselves suffer from necessarily coarse sampling and consequent inability to resolve
signals in single growth increments. Determining the proper interpretation of the Phanerozoic δ18O
trend is of first-order importance for understanding the nature of the environments in which earlyanimals arose and evolved, and sclerochronology can play a critical role in resolving this debate. The
mean body size of fossilized marine animals has also increased through the Phanerozoic. Along withconcomitant increases in motility, proportion of predators, and the composition of primary producer
communities this has been taken as evidence that mean per-capita metabolic rates have increased.
On shorter timescales, many lineages exhibit reduced size in the aftermath of major mass extinction
events. Changes in mean size can result from changes in lifespan or in growth rate, and these havequite different implications regarding the process(es) driving evolutionary trends. However, little
is known about growth rates or lifespans in the great majority of extinct clades. Even in modern
calcifying groups, comparatively little is known about the controls on growth rate: are growth
rates more strongly determined by extrinsic environmental conditions such as temperature andproductivity or by intrinsic aspects of physiology that may be conserved across broad phylogenetic
groups? Such uncertainties hamper efforts to reconstruct ancient ecosystems and to understand theenvironmental drivers of macroevolutionary trends. Sclerochronologists have developed a mature setof tools that, carefully applied, can shed considerable light on the evolution of marine ecosystems
through time.

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4th International Sclerochronology Conference, ISC 2016

Seasonal patterns in shells of Concholepas concholepas andits application at the archaeological site of Camarones 14(Camarones River Valley, Chile)
Teresa C. B. Franco1*
Department of Anthropology, Vanderbilt University, Nashville, TN, USA1*corresponding author: tfranco@gmail.com

The Chinchorro culture of the north coast of Chile (7000-3500 BP) is best known for its maritime
economy and mummification of the dead. Not known is how the Chinchorro people articulatedwith and managed both the maritime and desert coast of the region to develop their complex
culture and whether these people had a sedentary lifeway. In this presentation I show the results ofgrowth-ring analyses of the shells of the marine gastropod Concholepas concholepas that have been
excavated from cultural deposits at the coastal site of Camarones 14 in the Camarones River Valley
to document occupational seasonality and possible long-term occupation. The approach is basedon seasonal patterns observed in the direction of the angles formed by the internal growth lines onmodern shells of Concholepas concholepas and compared with the archaeological samples. Although
this is a new approach it shows potential use to estimate seasonality of site occupation.

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5th-9th June, 2016 • Portland, Maine, USA

Evidence for growth rate nonlinearity in bamboo corals
Megan Maria Freiberger1*, Hannah Miller1, Tessa M. Hill2, Ann McNichol3, Mary
Lardie Gaylord4, Michele LaVigne1
Bowdoin College, Brunswick, ME, USA, 2UC Davis Bodega Marine Laboratory and Department of Earth and Planetary
Sciences, Bodega Bay, CA, USA, 3Woods Hole Oceanographic Institution, Woods Hole, MA, USA, 4National Ocean
Sciences Accelerator Mass Spectrometry Facility, Woods Hole Oceanographic Institution, Woods Hole, MA, USA1*corresponding author: mfreiber@bowdoin.edu

Bamboo corals, long-lived gorgonian octocorals living at depths of ~700-2000 m, represent uniquearchives of intermediate water conditions. These Isididae corals are characterized by alternatingorganic nodes and calcitic internodes, which give them an appearance reminiscent of a bamboo
shoot. While coral internodes can be analyzed by LA-ICP-MS to obtain proxy data, constructing
firm chronologies for these samples is difficult. The anthropogenic 14C bomb spike recorded in coral
organic nodes provides tie points for calculating radial growth rates, but low sampling resolution has
led to the convention of applying a single growth rate to an entire bamboo coral record. In this studyof radiocarbon-based chronologies in 6 bamboo coral samples from the California Margin, nodes
were sampled at high enough resolution (<0.5 mm) to resolve the entire 14C bomb spike (including
three tie points linked to the initial 14C rise in 1957, 14C peak at 1970 and collection date at 2007) for
four samples collected live, as well as a partial spike in two samples which were not collected live.
Radial growth rates ranged from 10 μm year-1 to 204 μm year-1, with a growth rate decline between
1957-1970 and 1970-2007 indicative of declining growth rates with specimen age and size. This was
confirmed by a strong negative correlation between growth rate and coral radius (R2 = 0.5 for linear
regression with corals with > 2 tie points). To provide a mechanistic basis for these observations,a simple mathematical model was used to predict radial growth rates as a function of radius under
the assumption of limited food supply where a constant volume of organic material is deposited
with time. Although the nonlinear, near exponential decline in growth rate illustrated by this model
fell within the 95% confidence interval of the linear regression, reconstructing the 14C bomb spikeusing nonlinear and linear growth rate models revealed that only the nonlinear model accurately
reconstructed the expected 14C curve. The implication of these findings for paleoceanographersinterested in utilizing bamboo corals is that chronologies incorporating a nonlinear decline in growthrate with coral radius, driven by a constant increase in node volume with time, are likely more
precise than those built on the assumption of constant radial growth rates.

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4th International Sclerochronology Conference, ISC 2016

Upwelling seasonality in the Iberian upwelling system fromshell δ13C records in the bivalve Glycymeris glycymeris
Pedro Freitas1*, Carlos Monteiro1, David Reynolds2, Paul Butler3, Christopher
Richardson3, Miguel Gaspar1, James Scourse3
Instituto Português do Mar e da Atmosfera (IPMA), Lisbon, Portugal, 2School of Earth and Ocean Sciences, Universityof Cardiff, Cardiff, Wales, UK, 3School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK
1*corresponding author: pedro.freitas@ipma.pt

Eastern Boundary Upwelling Systems (EBUS’s) are among the most diverse and productive marine systems.
Knowledge of past upwelling variability is essential to correctly predict the environmental and economic
impacts of EBUS’s in future climate change scenarios. The seasonally variable Iberian Upwelling System(IUS), the northern section of the Canary Current Eastern Boundary Upwelling Ecosystem (CUE), which
albeit placed at a crucial climatic boundary position, lacks well-dated high-resolution proxy records ofpast environmental variability that can be extend to periods before instrumental records. Variability in the
IUS is complex, with upwelling intensity and sea surface temperature shown to oscillate at sub-decadal tomulti-decadal time scales in association with the Eastern Atlantic Pattern and the Atlantic Multi-Decadal
Oscillation.
Bivalve shells contain annually- and sub annually-resolved records of shell growth (sclerochronology)
that provide robust high-resolution archives of oceanographic and climatic data variability. However,sclerochronological studies have largely focused on shells from coastal waters in northern and temperate
latitudes. Such studies in shells from southern European coastal shelf seas have been limited by the rarityof long-lived bivalve species (i.e. several decades to hundreds of years). The dog cockle, Glycymeris
glycymeris, with a longevity >100 years, provides a novel sclerochronological archive for reconstructing pastenvironmental variability in the CUE. In this study, carbon stable isotope (δ13C) profiles in G. glycymeris
shells from the IUS were obtained at sub-monthly and annual resolutions to determine the potential of shell
δ13C as a proxy for changes in upwelling conditions in the IUS.
Profiles at sub-monthly resolution demonstrated that shell δ13C variation is inversely synchronous to
upwelling intensity and is likely explained by seasonal changes in upwelling-related ventilation of surface
waters with lower δ13CDIC subsurface waters, i.e. higher upwelling during spring-summer lowers surface water
δ13CDIC, and thus lowers shell δ13C.
Profiles of annually-resolved δ13C records from 1955 to 2013 CE showed a marked and stable ontogenetic
decreasing trend. However, removal of the ontogenetic trend to extract higher frequency δ13C variability
produced a mean annual δ13C index which had a similar variation to the inverted amplitude in upwelling
intensity (AUI) between the high and low upwelling seasons (JAS-DJF). A potential mechanism is proposed
where AUI changes the seasonal growth bias in the seawater δ13CDIC signal integrated by annual shell δ13C.
Consequently, high (low) AUI would bias shell growth towards the high (low) upwelling season, and thus
lower (higher) δ13CDIC and ultimately lower (higher) shell δ13C. Replication and the extension of δ13C records
are needed, as well as validation of the mechanism linking shell δ13C to UI and δ13CDIC seasonality, to confirm
G. glycymeris shell δ13C as a valid proxy for seasonality in the IUS.
This study was financed by the Portuguese FCT as part of the frame of GLYCY Project (contract PTDC/AACCLI/118003/2010).

50

5th-9th June, 2016 • Portland, Maine, USA

Trace and major element ratios in Elliptio dilatatus shells as
indicators of surface water quality in western Pennsylvania
Thomas Geeza1*, Nathaniel Warner1
Penn State University, State College, PA, USA1*corresponding author: tjg5157@psu.edu

Centralized waste treatment facilities in western Pennsylvania accept, treat, and discharge
conventional oil and gas wastewaters. This wastewater contains elevated levels of Cl, Br, Ba, Sr, andRa among other trace elements. Prior to 2012, these facilities also accepted unconventional flowback
and produced water. While unit processes in these treatment plants are designed to remove many
species, some elevated loads of Cl, Br, Sr, and Ra are discharged into waterways. Previous researchon these waterways suggests that discharge from these facilities has led to accumulation of radium
in sediments and has possibly contributed to habitat loss and further decline of multiple endangered
mussel species including Epioblasma torulosa rangiana and Lampsilis abrupta. Mussels are used
as a bio indicator species in waterways due to their ability to sequester and incorporate many trace
metals into their biomass and shell. This work analyzes concentrations of metals in shells of mussels
as an indicator of water quality and to determine if accumulation of elements present in the dischargeof brine treatment facilities are bioaccumulating in the nearby environment. We measured major andtrace element ratios by laser ablation inductively coupled plasma mass spectroscopy (LA-ICPMS)
in shells of Elliptio dilatatus, a member of a common genus of mussel. Combining element ratioswith 18O/16O ratios (δ18O) we can observe seasonal trends along the growth bands of the shells andmore accurately date changes in concentration within the shells. We can also use 87Sr/86Sr ratios
measured by multi-collector ICP-MS (MC ICP-MS) to indicate the likely origin of the strontium(e.g., mine drainage, oil and gas wastewater). Elevated ratios of Ba/Ca, Na/Ca, and Sr/Ca in theshells of Elliptio dilatatus collected downstream of one wastewater treatment facility correspond toperiods of the highest reported discharge from that facility (2009-2012). Sediment cores collectedfrom a lake downstream of a similar facility has confirmed both elevated strontium concentrationsin the sediment deposited during the time period of highest discharge as well as exhibiting a87
Sr/86Sr indicative of unconventional oil and gas activity. Future work will look to more completely
characterize the spatial extent and determine fate and transport of metals within the local ecosystem.

51

4th International Sclerochronology Conference, ISC 2016

Reconstructing hydrological changes over the past century inCentral Africa using freshwater bivalve shells
David Gillikin1*, Zita Kelemen2, Holly Havel1, Lauren Graniero3, Athanase Yambélé4,
Steven Bouillon5
Union College, Schenectady, NY, USA, 2KU Leuven, Leuven, Belgium, 3University of North Carolina, Chapel Hill,
NC, USA, 4Service de l’Agrométéorologie et de Climatologie, Direction de la Météorologie Nationale, Bangui, Central
African Republic, 5KU Leuven, Department of Earth & Environmental Sciences, Leuven, Belgium

1*corresponding author: gillikid@union.edu

Bivalve shell oxygen isotope ratios (δ18Os) record both water oxygen isotope values (δ18Ow) andwater temperature. However, in the tropics, temperature variations are minimal and variations inδ18Ow values dominate the shell signal. Therefore shells can be used as archives of variations inδ18Ow values. δ18Ow values in turn predictably vary with changes in the hydrologic cycle – including
precipitation and evaporation. We investigate δ18Os values of Chambardia wissmanni shells collectedfrom the Oubangui River (Bangui, Central African Republic) over several years between 1908 and2013 (one shell from 1908, two from 1914, one from the 1950s, and nine shells collected between
2011 and 2013). One Aspatharia rochebrunei shell from the Ibéléké River in the Ngotto rainforest
about 160 Km west of Bangui (a tributary of the Lobaye, which meets the Oubangui downstreamof Bangui) was also included in the analysis. Biweekly water samples and in-situ measurements
collected over a period of 2 years (2010-2012) allowed a direct comparison with proxies recordedin shells. Seasonal minima and maxima in δ18Oshell (-5.1 to +0.2 ‰) agreed well with predictedvalues calculated based on temperature and δ18Ow (see Kelemen et al. in this abstract volume).
Archived museum specimens from the Oubangui River cover the time periods between 1891 andthe 1950s. δ18Os analyses on all pre-1950s specimens show that seasonal maxima in δ18Oshell are
significantly lower (~-2.5 ‰) than in recent shells (+0.2 ‰), while seasonal minima (-4.3 ‰) arein closer agreement with recent shells. This strongly suggests the dry season in the upper Oubangui
basin has become drier in recent decades, which confirms decreased river discharge over this time.
Interestingly, the shell collected just 160 Km to the west in the rain forest is similar to the pre-1950sshells. This suggests that the drier conditions in the Bangui region seen post 1950s is a regional
phenomenon and is likely driven by precipitation-evaporation (P-E) budgets and not necessarily
by changes in rainfall δ18O values. Changes in P-E can be caused by land-use change or increased
evaporation from warmer air temperatures. This suggests that land-use change and/or climate change
is significantly threatening local water resources in Central Africa.

52

5th-9th June, 2016 • Portland, Maine, USA

Paleoclimate reconstruction from oxygen isotopes in a coralskeleton from East Africa
David Gillikin1*, Anouk Verheyden1
Union College, Schenectady, NY, USA1*corresponding author: gillikid@union.edu

We present a lab activity that both illustrates how marine paleoclimate records are reconstructedfrom biological carbonates and strengthens student’s spreadsheet and basic statistical skills. Students
use published coral isotope data downloaded from the National Oceanographic and Atmospheric
Administration Paleoclimate Database to develop a paleotemperature equation from oxygen isotope
data paired with sea surface temperature (SST) data. They then use this equation to hindcast SST
back to the beginning of the coral record in 1801. Students are exposed to isotope geochemistry (at abasic level), as well as error analysis, and how paleoclimate data are generated.

53

4th International Sclerochronology Conference, ISC 2016

Detecting seasonal variations in nitrogen and carbon sources toan impacted river and its estuary using bivalve shell δ15N andδ13C values
Lauren Graniero1*, Donna Surge1, David Gillikin2
Dept of Geological Sciences, University of North Carolina Chapel Hill, Chapel Hill, NC, USA, 2Dept of Geology, Union
College, Schenectady, NY, USA1*corresponding author: graniero@live.unc.edu

Estuaries are dynamic ecosystems susceptible to the combined effects of anthropogenic influenceand global climate change. In particular, excess nutrient inputs cause eutrophication and overallwater quality degradation. In the Neuse River Basin, NC, excess nutrients enter waters via effluent
from several concentrated animal feeding operations (CAFOs), atmospheric deposition, fertilizer
use, and wastewater treatment plants. These sources have distinguishable δ15N, δ13C, and C:Nvalues due to predictable fractionations in N and C isotope ratios. The combined seasonal andspatial variations in the biogeochemistry of water and bivalve shells allows for chronologicalmonitoring and assessment of these sources to the Neuse River and its estuary. Preliminary bivalveorganic matter (muscle, mantle, gill, and stomach) data suggests that there is measurable spatial
heterogeneity in nutrient sources to the Neuse River and its estuary. Average freshwater mussel tissue
values from two Elliptio complanata indicate that upriver sites (δ15N=8.0±0.8‰, δ13C=-31.4±0.6‰)
are isotopically distinguishable from downriver sites (δ15N=9.9±0.7‰, δ13C=-32.6±0.4‰). Average
estuarine bivalve tissues from ten Rangia cuneata exhibit higher δ15N (11.5±0.8‰) and δ13C(-30.3±0.4‰) values compared to riverine sites. The C:N ratios between riverine and estuarine
bivalve organic matter are indistinguishable. In R. cuneata, the range in mantle and gill δ15N values
for shells collected on the same day (n=5) are similar, whereas muscle tissues have notably higher
δ15N values and stomach tissues have lower δ15N values. In E. complanata, there are not enoughspecimens to make a sufficient distinction. Further research will determine whether serially sampled
bivalve shell δ15N and δ13C values record temporal and spatial variations in riverine and estuarine N
and C sources and biogeochemical cycling.

54

5th-9th June, 2016 • Portland, Maine, USA

Coralline algal paleoclimatology – A review of current status
and challenges
Jochen Halfar1*
University of Toronto, Mississauga, ON, Canada

1*corresponding author: jochen.halfar@utoronto.ca

Coralline algae are a globally distributed group of shallow marine benthic calcifiers that canform annual growth increments in a high-Mg calcite skeleton. Over the past 15 years a numberof both free-living and encrusting coralline algal genera have been tested for their suitability as
climate recorders and to date several multicentury long reconstructions of ocean climate have been
generated. Coralline algal proxy studies span regions ranging from the tropics to arctic latitudes,with most studies focussing on mid- and high-latitude regions of the Northern Hemisphere. In highlatitudes coralline algae are considered to be the single most abundant shallow benthic marine
calcifier, sometimes covering up to 100% of the seafloor in the shallow photic zone. Proxy studies
include both free-living rhodolith nodules and attached crusts forming build-ups on hard substrate.
Environmental interpretation of rhodoliths, which are generally found on soft-substrate seafloor, iscomplicated by the fact that rhodoliths are overturned at infrequent intervals by water movement
and benthic organisms, with opposite nodule sides receiving contrasting light conditions at any
given time. This severely limits proxy reconstructions, since skeletal growth and trace element
incorporation of the photosynthetic coralline algae is primarily controlled by light and temperature
variability. In contrast, crusts of the massive growing coralline alga Clathromorphum sp., that forms
abundant build-ups throughout the Subarctic and Arctic including regions seasonally covered bysea ice, remain in a fixed position throughout their up to 650 year long lifespan, while faithfullyrecording environmental conditions. With an absence of an ontogenetic growth decline and annual
growth rates varying between 80-400 µm as a function of temperature and light variability, seasonal
to annual resolution proxy reconstructions have been possible in regions as far as 73°N. To date,
Clathromorphum sp. has yielded interpretations of past ocean temperature, cloud cover, freshwater
influx, ocean pH and sea-ice conditions. The latter application is currently the focus of intense
research, since the Arctic-wide occurring Clathromorphum is the only annual resolution marine
sea ice proxy available to date. However, our understanding of Clathromorphum proxy recording
has been hampered by an inability to achieve representative algal growth in controlled mesocosm
experiments. Those experiments were designed to gain a better understanding of the relative
influence of temperature and light on the photosynthetic proxy, evaluate interspecimen variability as
well as to shed light onto calcification mechanisms, which to date are poorly understood. In addition
to ongoing efforts of proxy calibration, basic questions such as distribution and occurrence ofClathromorphum buildups suitable for sclerochronological work are being addressed by upcoming
expeditions to the core Arctic.

55

4th International Sclerochronology Conference, ISC 2016

Sclerochronology of a large predatory gastropod (Busycon
sinistrum) to determine late prehistoric seasonality at St.
Joseph Bay, Florida
Ryan Harke1*, Gregory Herbert1, Nancy White1, Jennifer Sliko4
University of South Florida, Tampa, FL, USA, 2Pennsylvania State-Harrisburg, Middletown, PA, USA,1

*corresponding author: ryanh2@mail.usf.edu

Recent archaeological investigations indicate that coastal Fort Walton cultures in the St. Joseph
Bay region of northwest Florida emphasized marine and estuarine foraging. These late prehistoric,
Mississippi-period (A.D. 1000-1500) peoples collected fish, shellfish, and other aquatic resources.
At the Richardson’s Hammock site (8Gu10), radiocarbon-dated to about A.D. 1300, large,
predatory gastropods were a major subsistence component. This adaptation is in sharp contrast
with that of contemporaneous inland Fort Walton societies, who relied on maize agriculture, andraises the question whether coastal groups were separate hunter-gatherer-fisher populations or
migrated seasonally from inland farming villages. We perform stable oxygen and carbon isotope
sclerochronology on lightning whelks (Busycon sinistrum) to determine the seasonality of Fort
Walton foraging and to compare the environment of prehistoric St. Joseph Bay with that of themodern bay. Oxygen isotope profiles suggest that shellfish collecting was relegated primarily tothe summer months, producing a scheduling conflict with the primary growing season for maize
in northwest Florida. Thus, coastal and inland Fort Walton sites could represent separate culturegroups. The relationship between δ18Oshell and δ13Cshell indicates similar environmental and climaticconditions between prehistoric St. Joseph Bay and today. However, modern whelks are depleted in
13
C compared to Fort Walton whelks, which reflects both twentieth century CO2 emissions and yearsof dredging and wastewater pollution entering the bay.

56

5th-9th June, 2016 • Portland, Maine, USA

It’s not all death and destruction: Thermal performance,energetics and the key role of monitoring growth responses toglobal climate change
Brian Helmuth1*
Northeastern University, Boston, MA, USA1*corresponding author: b.helmuth@neu.edu

By definition, global climate change is affecting organisms and ecosystems worldwide, but these
impacts often play out at incredibly local scales. For example, the ability of organisms to use
microclimates can lead to differences in environmental stress over the scale of tens of cm that canexceed much larger-scale patterns observed over tens of degrees of latitude. An increasing numberof studies are showing that rather than conforming to simple latitudinal gradients, many species
live along what may best be considered as geographic mosaics of environmental stress. Moreover,non-climatic and climatic stressors do not always conform to the same geographic patterns, so that
exposure to multiple stressors can be highly complex. Forecasting the likelihood of future responses
to environmental change therefore requires not only that we understand the complicated ways inwhich multiple stressors affect organisms to create “winners” and “losers,” but also that we gaina better understanding of how the temporal and spatial coincidence of these stressors will occur
in nature. Energetics modeling provides an effective means of integrating the consequences ofmultiple stressors to organismal physiology. A primary finding of many of these studies is that thefirst observable impacts of climate change are not simply the result of rare but lethal extreme events,
but also the cumulative effects of more chronic levels of stress on patterns of growth, reproduction
and fitness. The production of hindcasting and nowcasting models of nonlethal responses toenvironmental change based on first principles, which can then be validated using cutting-edgesclerochronology methods in animals such as bivalves, offers new opportunities for interdisciplinary
collaboration that will likely provide critical insights into climate change ecology.

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4th International Sclerochronology Conference, ISC 2016

Reproducibility of Clathromorphum compactum coralline algal
Mg/Ca ratios and calibration to high-resolution sea surface
temperature data
Steffen Hetzinger1*, Jochen Halfar2, Andreas Kronz3, Klaus Simon3, Walter Adey4,
Robert Steneck5
GEOMAR Helmholtz-Centre for Ocean Research Kiel, Kiel, Germany, 2University of Toronto, Mississauga, ON,
Canada, 3University of Göttingen, Göttingen, Germany, 5Smithsonian Institution, Washington, DC, USA, 6Darling
Marine Center, University of Maine, Walpole, ME, USA1*corresponding author: shetzinger@geomar.de

Crustose coralline algae are important shallow-marine calcifiers that grow attached to the seafloor.
Their potential as high-resolution archives of past ocean variability has only recently beenrecognized. Coralline algae of the genus Clathromorphum form annual growth increments in theirhigh-Mg calcite skeleton and have been successfully utilized to reconstruct paleoclimate in mid- tohigh-latitude oceans over multicentury time spans. However, few calibration studies of coralline
algal proxies are available from these climatically important regions which have experienced drasticchanges in recent decades, even rarer are well replicated records from individual sites. Of particularinterest are records of temperature-dependent algal Mg/Ca ratios, which have previously been shown
to track ambient sea surface temperature (SST) and thus can serve as a paleotemperature proxy.
Here we present new Mg/Ca records from a number of Clathromorphum compactum specimens(Gulf of Maine, North Atlantic). Sections from C. compactum algal mounds were analyzed using
Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) yielding continuous
individual Mg/Ca records of up to 30 years in length. We first assess signal reproducibility and showthat algal Mg/Ca ratios are well reproducible both along several shorter transects within individual
sample specimens and between different samples from the same study site on seasonal to interannual
timescales. In addition to the testing of intra- and intersample signal replication, LA-ICP-MS-derived
Mg/Ca ratios are compared to electron microprobe (EMP) analyzed algal Mg/Ca on the longest-lived
sample specimens and were found to be within analytical error. Second, we calibrate our monthly
resolved records with in situ oceanographic data in order to achieve a reliable assessment of thepotential for paleotemperature reconstruction. We show that relationships to SST can be improved
when using sample composites (averaging of multiple transects per sample) and by averaging of Mg/
Ca records from multiple algal specimens. Sample composites and intersample averages generally
yield stronger relationships to SST data than Mg/Ca records derived from individual samples.
In summary, this study shows that reproducibility of algal Mg/Ca ratios is high within the tested
specimens of C. compactum and when comparing between individual samples. Thus, calibration ofalgal Mg/Ca ratios to SST data can be improved by using sample composites and by averaging datafrom several samples within a study site.

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5th-9th June, 2016 • Portland, Maine, USA

Paleoecological implications of nitrogen and carbon isotopic
data from organic material in Devonian rugose corals
Alaina Hickey1*, Chris Junium1, Linda Ivany1
Syracuse University, Syracuse, NY, USA1*corresponding author: anhickey@syr.edu

The Rugosa, an extinct order of coral, were dominant reef builders from the Middle Ordovician to
the Late Permian. There has been little research done on their paleoecology, particularly their feeding
habits and growth rates, and the aim of our research is to investigate stable isotope signatures fromboth extracted organic material of Middle Devonian rugose corals and their calcium carbonate
skeletons to provide insight into these unknowns. Corals were sampled from the Joshua Coral Bed
in the Hamilton Group in Central, NY. These coral beds range in thickness form ~1 m to as many as
20 m and may have covered several hundred square kilometers of the sea floor. Represented genera
include Cystiphylloides, Siphonophrentis, Bethanyphyllum, Heliophyllum and Heterophrentis. Corals
were physically and chemically cleaned to ensure that exogenous organic matter from host shales
was removed. Organic material is present in thin sections as thin filaments and remains as whispy
organic filaments in acidified residuals. The nitrogen and carbon isotopic compositions of preserved
organic material could provide substantial new insight into the diets and physiological processes of
Paleozoic rugosans. I will also report on oxygen isotopic ratios sampled from the calcium carbonate
shells for paleotemperature data, as well as carbon isotopic compositions to show the effects ofclimate variability on the mechanisms by which rugose corals construct their inorganic skeletons.

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4th International Sclerochronology Conference, ISC 2016

Micro-scale chemical analysis of statoliths from the whelk
Buccinum undatum: validation of a novel age determination
method for fisheries management
Phil Hollyman1*, Simon R. Chenery2, EIMF 3, Melanie J. Leng4, Konstantin Ignatyev5,David Righton6, Chris A. Richardson7
Bangor University, Bangor, Wales, UK, 2Centre for Environmental Geochemistry, British Geological Survey,
Nottingham, England, UK, 3Edinburgh Ion Microprobe Facility, University of Edinburgh, Edinburgh, Scotland, UK,
4
NERC Isotope Geosciences Facilities, British Geological Survey, Nottingham, England, UK., 5Science Division,
Diamond Light Source, Harwell Science and Innovation Campus, Didcot, England , UK., 6Centre for Environment,
Fisheries and Aquaculture Science (CEFAS), Lowestoft, England, UK, 7School of Ocean Sciences, Bangor University,
Menai Bridge, Wales, UK
1*corresponding author: osp20b@bangor.ac.uk

The whelk Buccinum undatum is commercially important in the North Atlantic; however, monitoring
populations has been problematic for fisheries scientists due to the lack of a robust age determination
method. We validated the periodicity of dark growth rings present in the calcium carbonate statoliths
located in the foot of field-collected and laboratory reared whelks using microscale measurementsof trace element geochemistry. Analogous in function to the fish otolith, a statolith contains a highresolution archive of past growth. Whelk statoliths were sampled from 3 locations spanning thelength of the UK (Shetland Isles = North; the Menai Strait (North Wales) = Mid; Jersey = South).
Using Secondary Ion Mass Spectrometry (SIMS), annual trace element profiles were reconstructed
at a 2 µm resolution. Clear cycles of 24 Mg concentrations are present with minimum values that
correspond with the visible dark statolith rings. Statoliths from 1 and 2 year old laboratory cultured
whelks of known age and life history contain 1 and 2 24 Mg cycles respectively. The reconstructionof seasonal seawater temperatures from oxygen isotope profiles from the matching shells show
annual temperature cycles that match the numbers of statolith 24 Mg cycles. The timing of statolithring formation appears to be during the winter season. The results obtained from the chemical
analyses of the shells and statoliths confirm the robustness of the statolith rings in estimating whelk
age and have allowed the construction of site specific growth curves using statolith age. µXRD at
2 µm spatial resolution show the statoliths are wholly aragonite in structure and thus trace element
variation is not the result of possible variations in polymorphs of the statolith CaCO3. The validationof the annual periodicity of statolith growth rings provides a robust and novel age determination
technique that could potentially lead to improved management of B. undatum stocks.

605th-9th June, 2016 • Portland, Maine, USA

Growing a sea monster: Isotope ecology of a giant heteromorphammonite
Linda Ivany1*, Emily Artruc1
Syracuse University, Syracuse, NY, USA,1

*corresponding author: lcivany@syr.edu

Diplomoceras maximum is a large, hamitcone heteromorph ammonite with a shell that resembles agiant paperclip. A 1.5 meter long specimen representing more than 3 meters of linear shell growthfrom the late Cretaceous Lopez de Bertodano Formation of Seymour Island, Antarctica, now resides
at the Paleontological Research Institution (PRI) in Ithaca, NY. Its growth rate and ecology havebeen the subject of much discussion but are completely unknown. Stable carbon and oxygen isotope
analysis of serially sampled shell material can provide insight into the growth and habitat of thesepeculiar cephalopods. A roughly half-meter section of shell containing a hook and both adjoining
portions of shafts, with aperture diameter ~15 cm, was sampled at a resolution of 5 samples per
sculptural rib on the shell (total of 145 analyses). δ18O values vary between +1.9 to -1.7‰, roughly
the same range expressed by co-occurring benthic mollusks. A 15-point moving average defines abroad sinusoid that likely reflects ~1.5 years of shell growth. If so, and if accretion were constant,
the PRI animal would have been about 9 years old at death. Superimposed on this sinusoid isregular variation of up to 2‰ that corresponds to sculptural ribs and covaries with δ13C, suggesting
the potential for disequilibrium effects during precipitation of ribs or, potentially, repeated verticalmigrations through the water column. Carbon isotope values overlap those of typical benthic
mollusks and other ammonites, but also include extremely negative values (+1.7 to -30‰). Values
are low between ribs and higher on them; regular swings to low values become significantly more
extreme in the hook than they are in the shafts. If related to disequilibrium and/or incorporationof metabolic CO2, this suggests more rapid growth in the hook section. Exceedingly negative δ13C
values may also reflect precipitation in the presence of methane, as suggested in the literature byunusual carbonate precipitates, chemosymbiotic cold-seep bivalve taxa, and very low δ13C valuesof cemented burrow fills. Taken together, the data suggest a pelagic habit near the bottom closely
associated with methane seeps. Shell growth is fast, consistent with living coleoids, and large
individuals are likely less than 10 years old at death.

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4th International Sclerochronology Conference, ISC 2016

Evidence, cause and consequence of exceptionally rapid growthamongst Pliocene scallops of the US eastern seaboard
Andrew Johnson1*, Annemarie Valentine2, Melanie Leng3, Hilary Sloane3,
Bernd Schöne4, Donna Surge5
University of Derby, Derby, England, UK, 2Southampton Solent University, Southampton, England, UK, 3British
Geological Survey, Nottingham, England, UK, 4University of Mainz, Mainz, Germany, 5University of North Carolina,
Chapel Hill, NC, USA1*corresponding author: A.L.A.Johnson@derby.ac.uk

Scallops are amongst the fastest growing of bivalves, with many species growing in the order of
40 mm per annum in early ontogeny, and reliable evidence of early ontogenetic growth-rates up
to 70 mm per annum in wild populations of certain species. From the evidence of oxygen isotope(δ18O) sclerochronology, modern examples of the western Atlantic genus Placopecten grow about
40 mm per annum in early ontogeny. The same approach reveals similar growth rates in Pliocene
examples from Virginia and North Carolina. By contrast Pliocene examples of the extinct genera
Chesapecten and Carolinapecten from Virginia grew at least 75 mm per annum, faster than has
been recorded in any wild modern scallop, and examples of Carolinapecten from Florida grew up
to 140 mm per annum, twice the maximum rate in wild modern scallops. The rapid overall growthof Carolinapecten is matched by exceptionally large microgrowth increments. In specimens withthe fastest overall growth the number of increments approximately equals the number of days
indicated by the oxygen isotopic data (e.g. c. 180 over half an oxygen isotope cycle), implying that
deposition was daily. Specimens with slower overall growth do not have smaller increments but
have substantially fewer than the number of days indicated by δ18O evidence, showing that reduced
overall growth was a consequence of periodic interruptions rather than permanently less favourable
conditions. Since few individuals lived more than a year, rapid somatic growth must have beenaccompanied by gamete production, implying abundant food resources. Intervals of particularly
rapid growth (largest microgrowth increments) are fairly closely correlated with increases in δ13C, asmight have been caused by phytoplankton blooms. However, there is little evidence that these were
stimulated by upwelling since there are few indications of a matching increase in δ18O (i.e. colder
water). Instead, primary productivity may have been enhanced by nutrient supply from the land.
Whatever the cause of high primary productivity in the Pliocene of the US eastern seaboard, thesubsequent demise of two scallop genera with exceptionally rapid growth seems as likely to relate toa decline in productivity as to a fall in temperature.

62

5th-9th June, 2016 • Portland, Maine, USA

Seasonal variation in temperature and precipitation during
Eocene cooling inferred from Antarctic bivalves
Emily J. Judd1*, Nicole M. Miklus1, Linda C. Ivany1, Willem P. Sijp2, Hagit P. Affek3
Syracuse University, Syracuse, NY, USA, 2University of New South Wales, Sydney, NSW, Australia, 3The Hebrew
University of Jerusalem, Jerusalem, Israe1

1*corresponding author: ejjudd@syr.edu

Climate change is one of the most pressing issues facing societies around the globe, yet changes
in seasonality and precipitation that accompany greenhouse conditions are still poorly understood.
Because global warming is amplified at the poles, studying high-latitude settings during warm
intervals in Earth’s geologic past can provide insights about future conditions. Several recent
studies have reported increased seasonal precipitation in high latitudes during the globally warm
Eocene Epoch (55-34 Ma), suggesting the possibility of monsoon-like conditions near the poles
during greenhouse climate regimes and hence a significant departure from the present-day climate
system. Climate model results suggest that increased summer precipitation and runoff would
create a brackish, isotopically negative lens on the surface of nearshore environments, prohibiting
vertical mixing within the water column and keeping shallow marine waters warm. With cooling,
precipitation and runoff would decrease, allowing for more consistent vertical mixing of cooler,deeper, marine water and resulting in a collapse in seasonal amplitude of temperature, withoverall cooling. Such a hypothesis is only testable with the high temporal resolution afforded by asclerochronological approach. We use seasonally resolved δ18Oaragonite data from fossil bivalves fromthe La Meseta Formation, Seymour Island, Antarctica, a nearshore shallow-marine succession,
to test for evidence of seasonal runoff of freshwater. Specimens from the genera Cucullaea
and Eurhomalea are sampled on a MicroMill using software that allows for 3D digitizing andmicrosampling of growth increments on shell exteriors rather than polished cross sections, resulting
in higher precision and larger sample sizes. To account for the variability in annual and ontogenetic
growth rate, and to resolve the issues related to time averaging biases created when serially samplingclams at a fixed interval, we employ a synthetic clam growth model coupled with temperature.
Samples from the late Eocene yield a more attenuated seasonal amplitude and higher average δ18O
value than those from the middle Eocene, consistent with the hypothesis that high-latitude marine
seasonality decreases with decreasing mean annual temperature, with cooling mostly in summer. By
augmenting these oxygen isotope data with seasonally resolved clumped isotope thermometry, we
can determine water temperature during seasonal extremes and thereby calculate the composition of
the water in both summers and winters, giving insights into runoff and hence precipitation regime.

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4th International Sclerochronology Conference, ISC 2016

Reconstructing past variability in African hydrology using
freshwater bivalve shell geochemistry: a multi-year calibrationfrom the Oubangui and Niger Rivers
Zita Kelemen1*, David Gillikin2, Lauren Graniero2,3, Holly Havel2, Athanase Yambélé4,
Steven Bouillon1
KU Leuven, Department of Earth & Environmental Sciences, Leuven, Belgium, 2Union College, Department of Geology,
Schenectady, NY, USA, 3University of North Carolina Chapel Hill, Chapel Hill, NC, USA, 4Service de l’Agrométéorologie
et de Climatologie, Direction de la Météorologie Nationale, Bangui, Central African Republic
1*corresponding author: zita.kelemen@kuleuven.be

We examined if African freshwater bivalve shells can be used as a proxy of oxygen stable isotope signaturesof river water (δ18Owater) and discharge. Daily discharge and sub-monthly δ18Owater data were collected over
several years from two contrasting African river systems: the Oubangui River at Bangui, Central African
Republic, and the Niger River at Niamey, Niger. For the Oubangui, δ18Owater data cover a period of five
years at two-weekly to monthly resolution, while for the Niger our dataset covers two years at a two-weekly
resolution. Nine specimens of Chambardia wissmanni, collected in the Oubangui, and five shells from theNiger River (one Aspatharia chaiziana, two Chambardia wissmanni, and two Aspatharia dahomeyensis,)
were analyzed for both δ13C and δ18O values along their growth axis; all shells collected have at least partial
overlap between their growth and the period of water sampling. In both river systems, water δ18O values
varied seasonally and were negatively correlated with discharge, with a logarithmic relationship (R2 ~ 0.75),
and with an overall large seasonal amplitude (-3.7 to +2.6 ‰ and -4.3 to +6.1 ‰ for the Oubangui and Niger,
respectively), while water temperature variations remained small. Based on measured δ18Owater values andwater temperature, we calculated the δ18O values for a ‘model’ shell assuming that carbonate is precipitatedin oxygen isotope equilibrium with the river water. For both river systems, δ18Oshell data matched model shelldata very well, and different species and/or specimens of the same species closely matched each other. Some
individuals, however, showed clear periods of growth cessation or reduction, and such growth gaps wereobserved during both high and low discharge periods. However, accurately reconstructing river discharge
based on shell δ18O data was only possible for periods of low discharge. δ18Owater values shift significantly
towards higher values during low flow conditions, resulting in a logarithmic relationship between dischargeand δ18Owater with little change in δ18Owater above a certain threshold discharge.
While δ13Cshell data typically show a similar seasonality as observed in δ18Oshell data, δ13Cshell data did not
closely match values expected based on riverine δ13CDIC (dissolved inorganic carbon) data, and a decrease
through ontogeny was also observed. This suggests that DIC is not the only source of C for the shell andthat metabolic C is likely incorporated into the shells as has been noted in other studies. In conclusion, ourextensive calibration study demonstrates that freshwater African bivalves secrete their shell in oxygen isotope
equilibrium with the ambient water, but suggests that the reliability of δ18Oshell values to reconstruct riverdischarge will depend on the local δ18Owater/discharge correlation. For the Oubangui and Niger River, our datasuggest that freshwater shells should be sensitive recorders of long-term changes in low flow conditions, but
are unlikely to accurately record changes in peak discharge regimes.

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5th-9th June, 2016 • Portland, Maine, USA

Reconstructing environmental histories of Atlantic cod in the
Gulf of Maine
Lisa Kerr1*, Zachary Whitener1, Graham Sherwood1, Steven Cadrin2, David Goethel3,
Adrienne Kovach4, Doug Zemeckis2
Gulf of Maine Research Institute, Portland, ME, USA, 2University of Massachusetts, Dartmouth, School for Marine
Science & Technology, Dartmouth, MA, USA, 3F/V Ellen Diane, 4University of New Hampshire, Dept. of Natural
Resources & the Environment, Durham, NH, USA1*corresponding author: lkerr@gmri.org

The study of fish otolith chemistry can provide information on the environment experienced by afish over its lifetime. Two major spawning complexes of Atlantic cod have been identified within
the Gulf of Maine: 1) the spring spawning complex, which spawns primarily in Ipswich and
Massachusetts Bay in the spring and, 2) the winter spawning complex which spawns in the same
region in winter months. Winter and spring spawning fish are genetically distinct and may exhibit
differences in the scale of their spatial behavior and habitat use. The goal of this research was
to characterize differences in the environmental histories of the two major spawning complexes(winter and spring) of Atlantic cod in the Gulf of Maine. Spawning fish were collected in winterand spring in the Gulf of Maine from Ipswich and Massachusetts Bays. Otolith thin-sections wereaged and analyzed across the longest growth axis of otoliths for a suite of isotopes, including
25
Mg, 55Mn, 43Ca, 138Ba, 88Sr, 63Cu, and 68Zn, using laser ablation inductively coupled plasma mass
spectrometry. The analysis of transects across the growth axis of the otolith provided the opportunity
to compare the chemical signature of the core (indicative of natal origin), the integrated transect
across the whole otolith (fingerprint of lifetime habitat use), and the transect profile (providing a highresolution environmental chronology that can be related to both year and age of the fish). Significant
differences in otolith elemental ratios were identified based on spawning time (winter and spring) as
well as location of spawning (Massachusetts and Ipswich Bay) early in life and across the lifetimeof fish. Significant differences in lifetime otolith growth were also identified between winter andspring spawners and spawners collected at different locations. Chemical chronologies were alignedwith the age of the fish and year during which growth occurred and chemistry and growth patterns
were compared across spawning groups. Differences in lifetime otolith elemental chronologies imply
different environmental histories and consequently can serve as an indicator of stock identity or life
history type. Increased understanding of differences in the spatial behavior of cod in the Gulf ofMaine will provide information relevant to preserving within species diversity in the Gulf of Maine.

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4th International Sclerochronology Conference, ISC 2016

Geochemical evidence for the presence of photosymbiosis in
Early Jurassic Lithiotid bivalve
Daniel Killam1*, Matthew Clapham1, Marco Franceschi2, Renato Posenato2
UC Santa Cruz, Santa Cruz, CA, USA, 2University of Ferrara, Ferrara, Italy1*corresponding author: dekillam@ucsc.edu

The Lithiotid bivalves (Lithiotis, Cochlearites and Lithioperna) were an aberrant bivalve groupwhich arose during the Pliensbachian stage of the Early Jurassic, following a 10 million year postTriassic extinction “reef gap”. During this period of the near-complete eradication of reef-building
corals, the Lithiotids became the dominant calcifiers in shallow tropical settings. Cochlearites
and Lithiotis have been proposed to harbor photosymbionts because of their large size, flattenedmorphology, tropical distribution and aggregate lifestyle. We have gathered shells of each genus
from the Trento Platform in Northern Italy and used stable isotopic sclerochronology to attempt
to determine whether Lithiotis shows a photosymbiotic vital effect similar to the one displayed by
known symbiotic groups such as the giant clams. If Lithiotis was photosymbiotic, we should seea δ13C enrichment in summer months when its proposed symbionts would have been most active,
as they preferentially fixing light 12C through photosynthesis. This would manifest as a negative
correlation between δ13C and δ18O sampling along a transect in shell carbonate (as δ18O values arelower during times of high summer temperatures). Preliminary results suggest that Lithiotis does not
display this negative relationship and does not have a highly accelerated growth rate, showing 2.5
cm/yr of growth, more in line with heterotrophic oysters than photosymbiotic giant clams. However,a longer transect needs to be collected along the longest axis of growth, collecting a longer isotopic
transect in order to determine whether a phase lag is present between the C and O isotope results,
and whether growth is faster in the vertical direction. When enough data is gathered, we will be able
to determine whether Lithiotis, previously considered a strong candidate for symbiosis, actuallydisplays a sclerochronological signal confirming this hypothesis.

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5th-9th June, 2016 • Portland, Maine, USA

Southeast Gulf of Mexico corals reveal annual barium cycles
Michèle LaVigne1*, Kristine DeLong2
Bowdoin College, Brunswick, ME, USA, 2Louisiana State University, Baton Rouge, LA, USA1*corresponding author: mlavign@bowdoin.edu

The coral skeleton barium to calcium ratio (Ba/Cacoral) has been shown to reliably record dissolved
barium concentrations (BaSW) in seawater. Ba/Cacoral has been used as a tracer of upwelling basedon the “nutrient like” BaSW depth profile, as well as a recorder of terrestrial runoff in some coastal
locations. However, a fifteen year long Siderastera siderea coral record from Dry Tortugas National
Park, FL (DRTO), a region of the Gulf of Mexico where upwelling and terrigenous influences areminimal, reveals large annual-scale variations in Ba/Cacoral (~7-20 μmol/mol). The application ofrecently published Ba/Ca calibrations derived from Pacific Porites and Pavona corals to the DRTO
S. siderea record suggests that these annual cycles correspond to changes in BaSW from ~60
nmol/kg (winter) to ~180 nmol/kg (summer). Although large in comparison to open ocean values,
previous studies have explained Gulf of Mexico BaSW concentrations of this magnitude as a resultof offshore drilling effluent discharge. The Ba/Ca maxima and minima lead those of SST by ~3months (as inferred from Sr/Ca measurements of sample splits), and the magnitude of the Ba/Cacoralcycles overwhelm any temperature influence, indicating that SST does not drive these changes. The
timing of the Ba/Ca maxima and minima does, however, align with the timing of annual chlorophylland δ13C minima and maxima, respectively, suggesting that this annual barium cycle is linked tobiological productivity. During the high productivity winter months, barium could be removed
from the dissolved pool either via direct cellular uptake or indirectly via barite precipitation withthe decomposition of large phytoplankton blooms. In addition to this biological cycling of barium,
submarine groundwater discharge, estuarine barium sourced from the Mississippi River, and therelease of drilling effluent on the Louisiana shelf could influence the Ba/Ca cycles recorded by thesecorals. Taken together, these results demonstrate the dynamic nature of barium cycling in surface
waters and the utility of a multi-proxy approach to trace biogeochemical cycling in the past.

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4th International Sclerochronology Conference, ISC 2016

Shellfishing through the Holocene in British Columbia:
Insights from oxygen isotope sclerochronology
Natasha Leclerc1*, Anna Sparrow1, Meghan Burchell1
Memorial University, St. John’s, NL, Canada

1*corresponding author: ndhlnl2@mun.ca

Shell middens from coastal British Columbia (BC), Canada, provide both cultural and biologicalinsights into past human-environmental interactions, and the direct analysis of shells provides
information about seasonality and local harvesting pressure. Previous analyses of macro-growthlines from butter clams (Saxidomus gigantea) distributed along 10,000 km of mainland and island
coastline provided a foundation to interpret the role of shellfish in local and regional economies overa 6000-year period. Combined with high-resolution stable oxygen isotope (δ18Oshell) and fortnightly/
lunar daily growth increment (F/LDGI) analysis revealed regional variation in seasonal shellfish
harvesting.
This poster synthesizes δ18Oshell from over 135 individual shells from 17 different sites, and growthincrement analysis of over 5000 S. gigantea shell fragments from 37 archaeological sites on the BC
coast. The results reveal region- and site-specific diachronic trends in shellfish harvesting strategies.
Since the cultural and geographic scope of this study is so large, understanding different growth rates
and salinity regimes is critical for applying stable oxygen isotope sclerochronology to understandpatterns of seasonal shellfish collection. This will be critical as seasonality research using δ18Oshell
expands into new geographical and cultural areas of BC, specifically within Sechelt inlet sincesummer salinity values are as low as 15 PSU compared to other study areas on the coast where
salinity ranged from 22-25 PSU.
The integration of new data from the southern region of BC, specifically from Sechelt inlet in
the traditional territory of the shíshálh Nation, adds to our understanding of seasonal subsistence
practices by comparing it with shellfish data from the traditional territories of the Coast Tsimshian,Haida Gwaii, Heiltsuk and Coast Salish peoples. The continued alignment of F/LDGI will ensure
continuity in our methodology and contribute towards a pan-coastal understanding of shellfishing
through the Holocene.

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5th-9th June, 2016 • Portland, Maine, USA

Losing track of time: Is hypoxia in part to blame for Baltic codaging problems?
Karin Limburg1*, Karin Hussy2
SUNY College of Environmental Science and Forestry, SUNY, Syracuse, NY, USA, 2DTU-Aqua, Charlottenlund,
Denmark

1*corresponding author: klimburg@esf.edu

Cod, a primary fishery species in the Baltic Sea since prehistoric times, has recently experienced
marked declines in size and condition. This is due to a combination of worsening water quality
conditions from hypoxia intensification, reduction in prey availability even as cod densities haverisen, and increased occurrence of parasites and disease. One of the net results of this has been adecrease in formation of clear annual growth rings in otoliths of Eastern Baltic Cod. Otoliths (earstones) are part of the hearing and balance system in fishes, and grow incrementally as a fish grows.
In seasonal environments, growth bands are laid down, much like tree rings. But in Eastern Baltic
cod it has become increasingly difficult to “read” otoliths and determine ages. This is a serious
problem, because age is a key variable used in stock assessment for the management of exploited
populations, including quota-setting. In 2014 the situation became so dire that the stock assessment
was not approved for this stock. Solutions are clearly needed. We are developing new methods toassist in solving the “aging problem” using a combination of otolith microchemistry, optical imagery
and direct increment counts, and dynamic models. Developing novel ratios of trace elements andisotopes that enhance seasonal signatures appears promising. We are also tracking the intensity ofhypoxia with a proxy (Mn:Ca ratios) as described in Limburg et al. 2015 (J. Mar. Sys. 141: 167-178).
This study explicitly links hypoxia with a metric (otolith Mn:Ca ratios) that also has a physiologicalbasis; preliminary results suggest our approach to deal with aging fishes badly impacted by hypoxia
is broadly applicable across marine to freshwater ecosystems.

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4th International Sclerochronology Conference, ISC 2016

Otolith biochronologies reveal latitudinal differences in growthof Bering Sea yellowfin sole Limanda aspera
Mary Elizabeth Matta1*, Thomas Helser1, Bryan Black2
Alaska Fisheries Science Center (NMFS/NOAA), Seattle, WA, USA, 2Marine Science Institute, University of Texas atAustin, Port Aransas, TX, USA1*corresponding author: beth.matta@noaa.gov

Because they accrete continuously and deposit annual growth increments over the lifetime ofa fish, otoliths (“ear stones”) act as chronometers of a fish’s life history. Growth-increment
biochronologies are often related to factors in the physical environment such as temperature. The
otoliths of yellowfin sole Limanda aspera are particularly suited to biochronology applications dueto the general clarity of their growth increments and relatively long life span. In a previous study,
a strong positive relationship was observed between a yellowfin sole otolith biochronology andbottom temperature in the southeastern Bering Sea. The aim of the present study was to determine
whether this biochronology-growth relationship is maintained in yellowfin sole at higher latitudes.
Two new biochronologies were developed from specimens collected near St. Matthew Island andthe Bering Strait and compared with the previously developed Southeast Bering Sea biochronology.
Despite large distances (600 km) apart, a high degree of synchrony was observed among all threebiochronologies. However, subtle differences among biochronologies were observed upon closer
examination. The St. Matthew chronology had the highest variability among individuals, possibly
due to differences in oceanography and productivity in that region. The relative amplitude of otolith
growth differed among the chronologies; stronger negative anomalies were observed in the south
whereas stronger positive anomalies were observed in the north. Differences in average length atage were also detected, with fish growing slower to larger lengths with increasing latitude. The
Bering Strait biochronology had the weakest and most localized relationship with climate variables,
suggesting that effects of climate are not felt uniformly across the regions examined. Differencesamong the three chronologies are discussed with respect to ecological and physical factors in thethree regions of interest.

705th-9th June, 2016 • Portland, Maine, USA

The challenges of a high-resolution archaeology:sclerochronological and isotopic approaches in perspective
Marcello A. Mannino1, 2*
Department of Archaeology, School of Culture and Society, Aarhus University, Højbjerg, Denmark, 2Department of
Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany

1*corresponding author: marcello.mannino@cas.au.dk

The palimpsest nature of archaeological deposits and their often coarse temporal resolution (e.g. in
the order of decades, centuries or millennia) allow us to study phenomena and processes at broad
scales of observation, which is useful to evaluate culture change over long periods of time. Sites,
however, are also repositories of organic remains of past human actions, which constitute archives ofpast climates and environments inadvertently preserved for us by their occupants. Sclerochronology
and isotope analyses on incremental skeletal structures, such as those of molluscan shells, offer
us the possibility of attaining high-resolution environmental and archaeological data, on yearly,
seasonal, monthly, weekly or even daily scales. High-resolution data is essential to assess whether, orin what way, changes in human behavior may have been linked to climate or changing environments,
given that it is to short-term changes that humans would have adapted to. This lecture addresses
how this is currently achieved by sclero-archaeology, as well as what methods and themes of inquiry
should be developed in the future.
An immediate strategic goal is to establish as palaeo-seasonality proxies all mollusc taxa which arearchaeologically common, by studying their living counterparts. These developments should not only beaimed at reconstructing season of mollusc collection, as is usually done, but at using shells as climatic andenvironmental records relevant for understanding past human behavior. Methodological progress should bemade to improve radiocarbon dating projects based on shells and to expand the range of sclero-archaeologicalapplications to provenancing shell artefacts. In fact, despite the fact that shell ornaments are proxies of pastsymbolism, languages or exchange networks, very little effort has been devoted to unravel the life histories ofthese shell artefacts, thereby limiting their potential as invaluable proxies of human behavior.
The rewards for embarking on targeted sclerochronological and isotopic studies of shells from a variety ofarchaeological periods and cultures are there for the taking. If similar strategies are pursued, high-resolution
research may allow us to tackle the ‘grand challenges for archaeology’ (Kintigh et al. 2014) and contribute toour understanding of how people in the past responded to abrupt environmental change over the short term.

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4th International Sclerochronology Conference, ISC 2016

Isotope sclerochronology and season of annual growthformation in the marine bivalve, Astarte borealis, from Arctic
and cold-temperate seas
Justin McNabb1*, Donna Surge1, Michael Zettler3
University of North Carolina, Chapel Hill, NC, USA, 2Leibniz Institute for Baltic Research, Rostock, Germany

1*corresponding author: jmcnabb@live.unc.edu

Astarte borealis shells are well suited to investigate links between environmental change andbiological consequences in high-latitude regions because of their long lifespans and abundance inboreal and arctic seas. These traits make A. borealis a useful tracker of the rapid climate changes
in the Arctic, a region experiencing double the global rate of temperature change. Therefore, it isimperative to understand the isotope sclerochronology of these shells to quantify how factors, suchas lifespan, are affected by climate change. Using isotope sclerochronology, we test the hypothesisthat this mid- to high-latitude species form winter growth checks in their shells similar to other midto high-latitude venerid clams (Mercenaria mercenaria) and patelloid limpets (Patella vulgata).
Specimens were collected alive from Kiel Bay, Germany (cold-temperate zone) and the White
Sea, Russia (boreal zone). Oxygen isotope data show that shells from the Kiel Bay populationof A. borealis slow growth in winter similar to other mid- to high-latitude molluscs most likely
representing cold-temperature stress. In contrast, shells from the White Sea slow growth during thesummer unlike other mid- to high-latitude molluscs. There are several factors that may contributeto the unexpected timing of slowed growth in the White Sea population, such as reproductive
processes, food supply, temperature thresholds, and salinity. We can rule out reproduction as acontributing factor because A. borealis has fertile gonads all year round. Nutrient restriction is
also unlikely because phytoplankton blooms occur from April to October. Summer temperatures
would not trigger slowed growth because typical values for the White Sea do not exceed maximum
temperature tolerances. The White Sea experiences pulses of meltwater during the early summers
which drop salinity to less than 8 psu (practical salinity unites) in some areas. This decrease insalinity is below the tolerance threshold for A. borealis and is a likely cause for the observed slow
summer growth.

725th-9th June, 2016 • Portland, Maine, USA

Marine climate variability of the Irminger Current based on
growth increments in the bivalve Arctica islandica: a molluscan
sclerochronological approach
Vilde Melvik1*, Carin Andersson2
University of Bergen, Bergen, Norway, 2UNI Climate, Bergen, Norway

1*corresponding author: vilde@melvik.no

The lack of high-resolution marine proxy records from higher latitudes limits our understanding of
natural climate change in these areas. Systematic instrumental observations of the ocean is available
from the last 50 years, only, and annually resolved climate archives such as corals are only sparsely
available in higher latitudes. In this study, we will examine the annual resolved growth incrementsof specimens of the bivalve ocean quahog (Arctica islandica), aiming to decipher environmental
change in the Irminger Current. The Irminger Current, a branch of the North Atlantic Current,
transports relatively salty and warm water westward along the south coast of Iceland. The changesof the different environmental parameters, such as temperature, salinity and primary productivity
that have occurred in the past will have had an impact on the living marine organisms in the northernareas, as well as various effects on the atmospheric climate. At northern latitudes, the changes inenvironmental parameters of the ocean are linked to the climatic conditions in the cryosphere.
Consequently, sea ice cover and glaciers on Iceland will be affected by changes in the Irminger
Current, and these fluctuations are possible to reconstruct using paleo archives from this area.
Synchronised response to changes in the environment within a population of A. islandica enables
cross-matching of the growth increment patterns of live-collected and sub-fossil specimens from thesame location. By implementing this method, it is possible to create a continuous multi-centennial
master chronology, which can be compared with both instrumental records of e.g. temperature andprimary productivity, and historical records. The growth increments will be measured along theventral margin in the direction of the maximum shell height as well as in the umbo. So far, thirteen
live-collected specimens of different sizes, collected from 104-meter water depth off the west coastof Iceland, have been processed. It remains to see if there is an adequate correlation between thespecimens to create a master chronology. To extend this study it would be interesting to compare thespecimens collected at deep water with specimens from more shallow water, to investigate to what
extent the signals correspond between different water depths.

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4th International Sclerochronology Conference, ISC 2016

Using shell-based proxy records from northern Norway toevaluate high latitude impacts of the Atlantic Multidecadal
Oscillation
Madelyn Mette1*, Alan D. Wanamaker Jr.1, Michael Carroll2, Michael Retelle3, William
Ambrose3
Iowa State University, Ames, IA, USA, 2Akvaplan-niva, Tromsø, Norway, 3Bates College, Lewiston, ME, USA1*corresponding author: mmette@iastate.edu

The Atlantic Multidecadal Oscillation (AMO) is thought to be a persistent feature of North Atlantic
Ocean climate variability, switching between warm and cool periods on the order of 60-80 years. The
lack of long-term, high-resolution surface ocean records, however, hinders a complete understandingof its persistence, interactions with other climate modes, and possible forcing mechanisms. Evidence
for the AMO’s influence and persistence at high northern latitudes is especially scarce (Drinkwater
et al., 2014). Arctica islandica shell-growth and geochemical records from northern Norway show
significant correlations with the AMO index over the past 112 years (r2 = 0.39). Running correlations
with the North Atlantic Oscillation vary in sign coincidently with AMO phases, suggesting complex
air-sea interactions at high latitudes. Extending the shell-growth and geochemical records for several
centuries will provide insight into the AMO’s influence in the Barents Sea, and help establish thelong-term dynamics and persistence of the AMO.

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5th-9th June, 2016 • Portland, Maine, USA

Mechanical and structural response of Cerastoderma edule
shell to acidification
Stefania Milano1*, Bernd R. Schöne1 Schunfeng Wang1, Werner E. Müller1
University of Mainz, Mainz, Germany

1*corresponding author: smilano@uni-mainz.de

Rising levels of carbon dioxide (CO2) emissions to the atmosphere have resulted in an increased
ocean pCO2, lower seawater pH and decreased carbonate saturation state. This condition potentiallyrepresents a major thread to calcifying organisms such as mollusks. The present study focuseson the impact of elevated pCO2 on shell microstructural and mechanical properties of the cockle,
Cerastoderma edule. Specimens were collected in the Baltic Sea and kept in tanks at six different
pCO2 levels ranging between 900 µatm (control) and 24,400 µatm. Extreme CO2 levels were used
to simulate the effects of potential leaks from the carbon capture and sequestration sites whereconsiderable quantities of CO2 are kept in sub-seabed geological formations. Two approaches werecombined to determine the effects of the experiment: (1) Scanning electron microscopy (SEM)
was used to analyze shell microstructures and dissolution damage and (2) nanoindentation wasused to test shell hardness and wear resistance. Size and shape of microstructural units in the outershell layer as well as shell hardness do not change significantly in response to acidified conditions.
However, ontogenetically younger portions of the shell were more affected by dissolution
pCO2 increased. Irrespective of pCO2, strong negative correlations exist between prism size andshell mechanical properties (hardness and wear resistance) in natural and artificial conditions.
An additional sample from the North Sea confirmed this result. Our findings suggest that the
microstructures and mechanical properties of C. edule are not significantly influenced by pCO2
variations. Furthermore, our study indicates that shell mechanical properties depend on the shellarchitecture at the µm-scale.

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4th International Sclerochronology Conference, ISC 2016

Otoliths: from individuals to assemblages in a changing world
John Morrongiello1*
University of Melbourne, Melbourne, VIC, Australia

1*corresponding author: john.morrongiello@unimelb.edu.au

Growth is a fundamental biological process, driven by a multitude of intrinsic (within-individual)
and extrinsic (environmental) factors, which underpins individual fitness, population demographics,
and assemblage productivity. Growth is not only responsive to ecological factors such as resource
availability and environmental conditions, but is also a trait under contemporary evolutionary
selection. Fish growth is therefore an ideal metric with which to study the impacts of natural andanthropogenic environmental change across all levels of biological organisation.
Otoliths provide fish ecologists and fisheries managers with an enviable source of biological data.
Whilst we have long taken advantage of the periodically formed increments within otoliths toprovide an estimate of fish age that can be readily used in stock assessment models, it is only more
recently that we have begun to interpret the growth information that these increments represent.
These aquatic biochronologies have enabled researchers to ask questions at daily to centennial timescales, in lakes to reefs to across large marine ecosystems, providing valuable ecological insight tofisheries ecology and management.
Here, I will discuss my recent work investigating the eco-evolutionary drivers of fish growth using
information naturally archived in otoliths. I will highlight how this data can be used to explore ahierarchy of growth variation, ranging from within- and among-individual responses to temperatureand fishing selectivity, to species-wide and assemblage-level assessments of fisheries, climatic, andoceanographic impacts. I will also present examples of how age information can readily be used
to recreate recruitment indices and in data poor fisheries. Throughout, I will make reference tostatistical models that facilitate the extraction and interpretation of biological insight from hardparts.
I will finish by exploring exciting opportunities for the use of otolith-derived growth information,
including the estimation of age at maturity and the development of improved predictions of fisheries
productivity. Otoliths have, and will continue to play, a vital role in furthering our ecologicaland evolutionary understanding of aquatic systems, and thus the management of our marine andfreshwater resources.

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5th-9th June, 2016 • Portland, Maine, USA

Latitudinal variation of lifespans and growth rates in modern
marine bivalves
David Moss1*, Linda Ivany1
Syracuse University, Syracuse, NY, USA1*corresponding author: dkmoss@syr.edu

Mean body size in marine animals has increased more than 100 fold since the Cambrian, a discovery
that brings to attention the key life history parameters of lifespan and growth rate that ultimately
determine the sizes attained by organisms. The longest lived non-colonial animal on the planet
today, Arctica islandica, is a bivalve with a maximum reported lifespan of 507 years. In addition
to Arctica, at least nine modern taxa are known to attain lifespans in excess of 100 years. Whatfactors might be involved in this impressive longevity? A handful of mostly species-specific studies
suggest that the longest lived individuals tend to be found at the highest latitudes of their geographic
range – implying a role for the environment. However, the pattern across the Bivalvia has not been
fully documented. Here, we present a new global database of maximum reported lifespan (MLSP)
and shell growth for 1,381 populations of marine bivalves and show that 1) lifespan increases, andgrowth rate decreases, with latitude, both across the group as a whole and within individual wellsampled taxa, and 2) that growth rate, and hence metabolic rate, correlates inversely with lifespan.
An environmental parameter related to latitude and therefore insolation, such as temperature or
primary production/food availability, acting through its effect(s) on metabolic rate, likely explains
the observed trends.
Our data set lays the ground work for testing hypotheses about relationships between life history
traits and spatio-temporal macroevolutionary trends using the modern and fossil record. If cold
temperatures at the poles is the main driver of today’s observed latitudinal pattern, we would
predict a change in intensity of that pattern in response to greenhouse versus icehouse conditions.
Alternatively, if the suggestion that food and nutrient availability in marine settings has increased
over the Phanerozoic is in fact true, we might expect to see an increase in von Bertalanffy k values(as a proxy for metabolic rate) as well. Despite the relative ease with which bivalve lifespans can be
determined from their shells, the longevities of fossil bivalves have only been reported in a handfulof studies. Discovering patterns of life history evolution in deep time using sclerochronology may be
the next frontier of paleobiological research.

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4th International Sclerochronology Conference, ISC 2016

Application of clumped isotopes in shell midden
sclerochronology
Peter Müller1*, Philip T. Staudigel2, Sean T. Murray2, Hildegard Westphal1,
Peter K. Swart2
Leibniz Center for Tropical Marine Ecology (ZMT) Bremen, Germany, 2Rosenstiel School of Marine and Atmospheric
Science (RSMAS), Miami, FL, USA, 2Rosenstiel School of Marine and Atmospheric Science (RSMAS), Miami, FL, USA,1

*corresponding author: peter.mueller@zmt-bremen.deGeochemical analyses of calcareous skeletal structures such as fish otoliths or mollusk shells fromarcheological sites provide sub-seasonally resolved records of paleoenvironmental conditions.
However, many prehistoric settlements were located in coastal or estuarine environments inwhich biotic or abiotic seawater conditions underwent large seasonal fluctuations (e.g. primary
production or salinity/δ18OWater) which complicates the straight forward interpretation of most
paleoenvironmental proxies. Carbonate clumped isotope thermometry represents a promising
analytical approach as it represents a direct measure of carbonate precipitation temperature
independent from the isotopic composition of the ambient water. However, recent studies haveshown that in particular aragonite is characterized by fast re-equilibration rates of 13C-18O bonds
due to closed systems isotope exchange reactions. Thus, clumped isotope thermometry might besusceptible to short-term heating events such as prehistoric cooking. To test this hypothesis, wemeasured the clumped isotopic composition of modern bivalve shells (Mercenaria campechiensis)
which were experimentally exposed to different prehistoric cooking methods. Our data clearlyshow that prehistoric cooking causes a considerable alteration of clumped isotopes as a function of
exposure time and cooking temperature. However, all cooking methods produced a characteristic
clumped isotopic signature primarily dependent on the cooking temperature showing that clumped
isotopes can be used to reconstruct prehistoric cooking methods in aragonitic shell midden
constituents. This is of particular importance because our data also show that all cooking methods
also caused a considerable alteration to other commonly used paleoenvironmental proxies even
without any conversion of the initial aragonite into secondary calcite. Thus, clumped isotope
thermometry represents a powerful tool to detect and reconstruct prehistoric cooking practices but
should also be considered for assessing sample preservation to prevent misinterpretations of ancient
climate conditions if samples were altered by prehistoric cooking methods prior to deposition.

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Understanding cellular-scale controls on Mg uptake in crustosecoralline algae
Merinda Nash1*, Walter Adey2, Jochen Halfar2
Smithsonian Institution, Washington, DC, USA, 2University of Toronto, Mississauga, ON, Canada

1*corresponding author: merinda.nash@anu.edu.au

Interpretations of past temperature are increasingly being made using changes in magnesium
content together with annual growth banding of crustose coralline algae (CCA). However, theseinterpretations can be limited by the lack of understanding as to how magnesium is incorporated
into the. Often published results for cold water CCA show unexplained spikes in Mg content thatare above values found in tropical CCA. Our recent research shows that the strongest control on
Mg incorporation is not temperature, but instead the Mg content is heavily dependent on the type of
calcification and cell growth mode. Mg content is higher in cell walls than the interfilament (between
cells). This offset has been found in both tropical and cold water CCA and the difference ranges from
5-8 mol% MgCO3. Furthermore, wound repair and basal hypothallial cells can also have elevated
Mg relative to the typical perithallial cells. These cellular scale controls can result in Mg contents inparts of cold water CCA being as high as tropical CCA. Prior to using CCA as a proxy, the different
types of cell growth need to be identified so that analyses can be restricted to only one cell type area.
Even within the one cell type, seasonal changes in relative amounts of cell wall to interfilament
can influence the total measured magnesium content. These biological controls do not prohibit theuse of Mg content in CCA as a paleo temperature proxy, but an understanding of the cellular scale
controls is necessary in order to make reliable interpretations using Mg content. Our results to dateshow that the tightest correlations for Mg and temperature are for temperatures less than 10 degrees
celsius. In contrast, the correlation weakens as temperatures increase to tropical. This shows the
CCA can be reliably used for cold water temperature reconstruction, however the correlation does
not consistently hold through temperatures up to the tropics.

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4th International Sclerochronology Conference, ISC 2016

Sclerochronological comparison of two dog cockle (Glycymeris
glycymeris L.) populations from the southeastern North
Atlantic
Alexandra Németh1*, Victor Quintino2, Zoltán Kern1
Hungarian Science Academy, Institute for Geological and Geochemical Research, Budapest, Hungary, 2University of
Aveiro, Aveiro, Portugal

1*corresponding author: nemethalexandra89@gmail.com

The use of the abundant dog cockle (Glycymeris glycymeris L.) in sclerochronological studies is provento be a valid method to reconstruct oceanographic variability in the North Atlantic Ocean, however, thesclerochronological potential of the species has not been investigated at the southern limit of its distribution.
The aim of our study was to analyse growth patterns of G. glycymeris specimens from near the southernborder of their species’ distribution and to compare the synchronous annual growth indices from twoenvironmentally different (sub-littoral and open marine) sampling localities to check whether the sameenvironmental variables affected the shells’ growth. The studied populations include a group of abandoned
shells that were collected offshore of the Desertas Islands, Madeira in 2013 at 80-300 m water depth range
together with two live-caught specimens and a second group of 13 shells that were collected alive in 2002 at
30 m water depth near Aveiro, Portugal. While these two collection sites represent two distinct habitats due totheir depths, they are both situated in regions affected by the Canary Current System and seasonally variable
upwelling systems.
The live collected shells from Aveiro were relatively young (the oldest specimen lived for 34 years). While
the abandoned shells from the Madeiran group proved to have very high ontogenetic ages (the oldest
specimen lived for 164 years). Both groups showed similar ontogenetic trends, however the average growthrate in the sub-littoral environment was three times higher in the first four years of their lives than it was in the
deeper collection site.
Subsets of the Madeira (n=18) and the Aveiro samples (n=6) could be collected into robust site chronologies
and negative exponential fitting was applied to derive standardized growth indices from the raw increments.
A good agreement was found (EPS>0.8 during 1950-2000) for the Madeira-group which suggests an external
effect on their growth. Their composite chronology exhibited negative correlation (r=0.4-0.5, p < 0.1.)
with the April-May HadISST1 SST fields around Madeira. The Aveiro composite chronology (EPS>0.85
between 1981 and 2001) also exhibited negative correlation with the May-June HadISST1 SST fields near thePortugese shores (r=0.4-0.6, p < 0.1). Earlier studies reported positive correlation between the growth indicesof G. glycymeris shells and seawater temperature, however our results suggests that in these southern sample
locations lower water temperature was not a limiting environmental variable and other external effect could
affect the shells growth.
Due to the seasonal variability of the Canary Current System the direction and strength of local currents andthe chlorophyll-a content of the surface seawater change during the year. The latter exhibits a maximum in
April when the currents from the NE direction become stronger and deliver cooler, nutrient rich water toMadeira. According to this, the positive correlation found between the Madeira composite chronology and theinterannual variations in regional mean meridional current velocity during the early summer months between
1993 and 2003 can point to a physiologically plausible relationship.

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The impacts of ocean acidification and increasing temperatureon shell properties of intertidal bivalve molluscs
Richard Patton1*, Christopher Richardson1, Andrew Davies1, Simon Chenery2
School of Ocean Sciences, Bangor University, Menai Bridge, Wales, UK, 2British Geological Survey, Nottingham,
England, UK
1*corresponding author: r.patton@bangor.ac.uk

The progressive increase in atmospheric carbon dioxide in the Anthropocene is causing potentiallycatastrophic changes in coastal marine systems. The world’s oceans have absorbed over 30% ofemitted CO2 since the beginning of the industrial revolution, thus mitigating part of the warming
effect, but resulting in a continuous decline in surface-ocean pH. Current models predict a reduction
in surface-ocean pH from 8.1 to 7.68 by the end of the century, with a simultaneous increase in meansurface-ocean temperatures of 2-4°C. As a result of increasing seawater pCO2, saturation states ofthe major calcium carbonate polymorphs (e.g. calcite and aragonite) are becoming lower, leading
calcifying organisms such as bivalve molluscs to be potentially vulnerable to the effects of ocean
acidification. We report on laboratory studies into the effects of ocean acidification and increases
in ambient seawater temperature on the incremental growth, shell thickness, shell microstructure,and physiological condition of juvenile blue mussel, Mytilus edulis and European common cockles,
Cerastoderma edule held under controlled conditions of tidal emersion and OA under a seasonaltemperature cycle.

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4th International Sclerochronology Conference, ISC 2016

The bivalve Glycymeris pilosa as a multidecadal environmentalarchive for the Adriatic and Mediterranean Seas
Melita Peharda1*, Bryan A. Black2, Ariadna Purroy1, Sanja Puljas3, Kresimir Markulin1,
Hrvoje Mihanovic1
Institute of Oceanography and Fisheries, Split, Croatia, 2The University of Texas at Austin, Marine Science Institute,
Port Aransas, TX, USA, 3University of Split, Split, Croatia,
1*corresponding author: melita@izor.hr

We evaluated the potential of G. pilosa as an environmental indicator for the Mediterranean region
by applying sclerochronological techniques. A sample set of shells (N=50) was live-collected from
Pašman Channel in the middle Adriatic Sea with individuals ranging in age from 24 to 69 years(N=44, x=45.6±11.4 years), 5 of which were older than 60. There was strongly synchronous growthamong individuals, though increments in 18 samples were not clear enough for crossdating and werediscarded from further analysis. Once visual crossdating was completed, growth-increment widths
in the remaining 26 individuals were measured. Mean sensitivity was 0.178, mean segment series
length was 37.3 years, and interseries correlation, representing the mean correlation between eachsample and the average of all others, was 0.592. A master chronology was developed by detrending
each measurement time series with a negative exponential function (N=23) or 50-year 50%
frequency cutoff cubic spline (N=3). A running EPS calculated over a 30-year window indicated thechronology was robust from 1969 - 2013, though the oldest G. pilosa was measured back to 1948.
The chronology significantly and negatively correlated with local summer sea temperatures (ST),
especially between August (r=-0.464, p=0.017) and September (r=-0.442, p=0.024). There wasalso a correlation with a multivariate index of circulation (cyclonic vs. anticyclonic patterns) in thenorthern Ionian Sea (r=-0.536, p=0.012). In summary, reduced growth tends to occur under warm,
saline, periods typical of cyclonic regimes. There was also an apparent terrestrial influence in which
growth significantly and positively correlated with November precipitation (r=0.410, p=0.020). Thisis typically the wettest period of the year during which terrestrial inputs would be at a maximum andmost likely to influence nearshore processes.
Live and dead G. pilosa shells were also collected from the northern Adriatic Sea, and preliminary
analysis indicates the longevity of dead-collected individuals is > 100 yr. Given this longevity,
clarity of annual increments, and broad geographic distribution, G. pilosa has considerable potential
to test hypotheses relating to environmental variability and biological response in the Mediterranean.
Indeed, the power of such analysis could be further expanded if chronologies from the closely
related Glycymeris bimaculata and Callista chione, for which preliminary data are promising, can beincorporated.

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A new method for age and growth rate determinations of theAtlantic surf clam (Spisula solidissima), based on internal
growth lines in ligament cross-sections
Pierre Poitevin1*, Julien Thébault1, Aurélie Jolivet2, Herlé Goraguer3, Pascal Lazure4,
Laurent Chauvaud5
Université de Bretagne Occidentale, Institut Universitaire Européen de la Mer, Plouzané, France, 2Bureau d’Ätude TBM
Environnement, Auray, France, 3Délégation de Saint-Pierre et Miquelon, Saint-Pierre et Miquelon, France, 4Ifremer,
Laboratoire Océan Côtier, Plouzané, France, 5Centre National de la Recherche Scientifique, Plouzané, France
1*corresponding author: poitevin.pierre@gmail.com

The Atlantic surf clam (Spisula solidissima) is an economically valuable burrowing bivalve widely distributed
along the northeastern coast of the United States and Canada. However, stock assessment surveys of Atlantic
surf clams in the Middle Atlantic Bight continental shelf show a trend of decreasing maximum shell length
over the past 30 years. This trend can be driven by fishery truncation (size selection), increasing bottom watertemperature or some combination of both. A prerequisite for any attempt to manage the fishery or monitor theenvironmental effects on this species is an understanding of Spisula solidissima growth rate.
Growth rates of bivalves not only differ among specimens, but they also vary throughout the growing
season and from year to year. This strongly suggests that shell growth of bivalves is partly governed bycommon external drivers. Moreover, many studies have already focused on the potential of marine carbonate
skeleton compositions, especially bivalve hard parts to record environmental conditions. Examination of
growth lines and increments preserved in hard structures is a relatively fast and cheap method to compare
shell growth rates in different localities. Annual lines (“annuli”) that are counted and used to age Spisulasolidissima are clearly visible in surf clam shell cross-sections (both in the outer shell layer and in the welldevelopped spoon-shaped chondrophore). However, in some cases or in some localities, disturbance lines
are undistinguishable from annual lines, thus leading to unreliable results. Further limitations occur in older
specimens because the most recently formed lines may be very close to each other, and/or the umbonal region
may be eroded thus hampering an accurate age determination. In view of these uncertainties, additional
methods for accurately interpreting these annual lines must be investigated. The internal ligament (resilium),
which is protected from damage or erosion by the valves and where distinct lines are clearly visible seems to
be a good candidate for accurate growth rate studies.
The purpose of the present communication is focused on the analysis of the surf clam population of SaintPierre and Miquelon (SPM), located 25 km off the south coast of Newfoundland, for which no growth studies
has ever been conducted. The objectives are: (i) to compare the growth lines present on the outer layer of theshell, the chondrophore, and the resilium and (ii) to describe annual growth variations using three different
hard parts of Spisula solidissima in SPM over the past 25 years. The results obtained from 30 individuals aged
from 8 to 27 years old collected in 2015, showed strong correlations between resilium growth lines and thetwo other shell parts “annuli”, especially with the chondrophore (r > 0.9). Those first results about surf clam
resilium growth lines, will provide a new reliable tool for fishery management of an economically important
species. Moreover, the associated knowledge related to the growth of this new archive (resilium) composedof oriented aragonite crystals in an elastic protein matrix, will open new fields of sclerochronological andsclerochemical studies related to Spisula solidissima environment and biology along the northeastern coast of
America.

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4th International Sclerochronology Conference, ISC 2016

The interaction of reproduction and shell growth in the bivalve
Callista chione
Ariadna Purroy1*, Melita Peharda1, Bernd R. Schöne2, Julien Thébault3,
Institute of Oceanography and Fisheries, Split, Croatia, 2University of Mainz, Mainz, Germany, 3Université de Brest,
Brest, France
1*corresponding author: ariadna.purroy@gmail.com

It is widely accepted that bivalve shell growth responds to environmental factors, however, few
studies analyze the influence of biological drivers on growth, including reproduction. We evaluatedthe reproductive cycle of Callista chione as a potential driver of shell formation rate. C. chione is
a commercially important species and due to its longevity (> 20 years) is an interesting target forsclerochronological studies. Sampling was conducted in two different environmental settings along
the eastern Adriatic coast: Pag – a semi-enclosed bay, and Cetina – a coastal site near a river mouth.
The monthly collection was carried out for a 18-month period from May 2014 until October 2015.
Temperature was measured hourly, whereas Chl a and δ13CPOM were determined monthly. Satellite
data for Chl a was also included in the study. The Gonadosomatic Index (GSI) was used as a unit ofmeasure for variation in gonadal mass. The oxygen isotope composition of several shells (δ18Oshell),once converted into seawater temperature, was used to determine the duration of the main growthseason.
Minimum monthly temperatures differed by ca. 4°C between Pag and Cetina (8.9°C and 12.7°C,
respectively), whereas maximum temperatures were similar. Chl a and δ13CPOM values showeddistinct temporal trends. A clear seasonal cycle in GSI was observed, however, it was notsynchronous between sites. In Pag, GSI started to increase in early spring and reached maximum
values during the summer, with a main spawning peak in July. In Cetina, increasing GSI values wereobserved during winter reaching maximum values in early spring, whereas spawning took place on
several occasions during late spring and summer. Based on δ18Oshell values, the fastest shell growthoccurred between the winter and summer (> 70%). The difference in temperature ranges may explain
the spawning lag observed between sites. The highest temperatures in Pag in 2015 coincided withthe main spawning peaks, while in Cetina temperature was inversely related to the GSI throughout
the year. A correlative allocation of energy to growth and reproduction was observed at both sites,with a decline in growth after spawning. The highest peaks in Chl a concentration occurred mostly
between November and April, a period with an increase in production of gonads. During this period,
an inverse relationship of Chl a and δ13CPOM values was observed. More positive δ13CPOM values,
indicative of fresh material, were related to periods following the main spawning peaks when the
GSI was low; conversely, more negative values were observed during the most ripe stages andmaximum spawning peaks. This suggests that the allocation of energy to growth was higher during
earlier reproductive stages when nutrients were more abundant, followed by a shift of energy
investment toward gonad production and a decrease in nutrients.

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5th-9th June, 2016 • Portland, Maine, USA

Test of North Atlantic sea-surface-temperature reconstructions
with pseudo proxy experiments over the last millennium
Maria Pyrina1*, Sebastian Wagner1, Eduardo Zorita1
Helmholtz Zentrum Geesthacht, Geesthacht, Germany

1*corresponding author: maria.pyrina@hzg.de

We test a Climate Field Reconstruction Method to reconstruct past sea-surface temperature in the
North Atlantic Ocean (NA) over the last 1000 years with a sparse network of proxy locations. We
use a set of climate model simulations (CMIP5 Earth System Models) and COBE2 reanalysis data ina pseudo proxy approach. With our approach we want to mimic records of an extremely long-lived
bivalve shell, Arctica islandica, and test whether this local proxy information can be used to makeinferences about the SST field of the whole North Atlantic Ocean.
For this test we use the so called Principal Component Regression analysis as one example of a
Climate Field Reconstruction (CFR). We carry out a set of calculations with pseudo-proxy locations
based on Arctica islandica’s collection sites. Practically, the pseudo proxies are the (undisturbed)
simulated or reanalyzed grid points co-located with the collection sites of the shells. Since oneof the main assumptions of CFR techniques relates to the temporal and spatial stationarity of therelationships between proxy indicators and large-scale climate patterns we tested the reconstructed
SST field evolution against different calibration periods.
We found that the evaluation of the CRF reconstruction (in terms of calibration statistics, spatial covariability structure etc) strongly depends on the individual model simulation used. The correlation
between the original and the reconstructed evolution of the SST anomalies is higher close to theproxy locations reaching values of between +0.6 and +1 over the eastern NA. In addition, thecalibration period exerts an influence on the reconstruction with the main structure of the spatial
correlation pattern between the original and the pseudo-proxy based SST field remaining the same.
Subtracting the trend of the SST anomalies in the calibration period during the 2nd half of the 20th
century does not affect the results. In future work, in contrast to the ideal pseudoproxies used here,
we will use noisy pseudoproxies for which the grid point temperatures will be contaminated with
proxy-specific noise based on the characteristics of Arctica islandica.

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4th International Sclerochronology Conference, ISC 2016

Mid and Late Holocene marine paleoenvironmental
reconstructions from Ingøya and Rolvsøya, northern
Finnmark, Norway
Michael Retelle1*, Samuel Mark1, Julia Savage1, Madelyn Mette2, Alan Wanamaker2,
Michael Carroll3, William Ambrose1
Bates College, Lewiston, ME, USA, 2Iowa State University, Ames, IA, USA, 3Akvaplan-niva, Tromsø, Norway

1*corresponding author: mretelle@bates.edu

Mid and late Holocene Arctic islandica shells from raised marine deposits were examined toreconstruct patterns in growth history related to marine conditions in northernmost coastal Norway.
Arctica shells were collected from two main sites in raised marine deposits on Ingøya (71°05 N
24°03E) and Rolvsøya (70°98 N 24°03 E). Shell-rich mid to late Holocene marine terraces andraised beaches are found from current sea level to the upper limit of the mid-Holocene Tapes
Transgression (9 meters asl on Ingøya). The mid-Holocene shells (ca. 6,000 B.P.) were collectedfrom reworked sandy marine and eolian deposits above a raised beach complex at Nordhamna on
northeastern Rolvsøya. The late Holocene (ca. 1,500 B.P.) shell samples were collected from a 3
meter high coastal bluff exposure at Østerbotn on central Ingøya in stratified gravelly and sandy
shallow marine deposits. Prior to undertaking detailed analyses, shell ages at each site weresurveyed using low precision 14C AMS then calibrated (CALIB 7.1, with Δ R of 72 ±18 years) to findshells with overlapping ages that could be used to provide crossdated records of growth increments.
The collections from Rolvsøya did not yield specimens of overlapping ages however 5 shells withoverlapping ages collected from the bluff section on Ingøya produced a 409 year shell growth seriesca. 1,400-1,800 calendar years BP.
Annual growth increments from two mid-Holocene A. islandica specimens, dated at 6,245 and
6,011 years B.P, and subsampled for interannual δ18O analysis establish an annual seasonality anddisplay a narrower range in summer to winter temperatures than currently exist in the region, which
is approximately 8°C. Furthermore, the older of the two specimens shows lower overall annual
temperatures and a greater seasonal temperature differential than the younger. The inversion oftemperature and seasonal amplitude may be a result of diminished vertical water column mixing
during warmer conditions.
Trends from both the 400-year late Holocene shell growth series and the detailed δ18O records
indicate substantial variability in the sub-decadal to multi-decal range, possibly related to largescale ocean-atmosphere dynamics. The late Holocene shell records display a pronounced seasonal
signal, with a mean seasonal variation of 4.7°C. These seasonal variations indicate an increase inseasonality through the Holocene, with mid-Holocene (~6,000 calendar year BP) shells having
the smallest range in seawater temperature seasonality. Although seasonality increased in the late
Holocene shells, modern shell values demonstrate an even larger range in seasonal temperatures.

865th-9th June, 2016 • Portland, Maine, USA

An integrated spatial data-model approach to reconstructing
and understanding Atlantic meridional overturning circulation
David Reynolds1*, Ian Hall1, James Scourse2, Paul Halloran3, Alan Wanamaker4,
Paul Butler2, Christopher Richardson2, Alexandra Nederbragy5, Jan Heinemeier5, Jón
Eiríksson6, Karen Luise Knudsen5
Cardiff University, Cardiff University, Cardiff, Wales, UK, 2Bangor University, Bangor, Wales, UK, 3Exeter University,
Exeter, England, UK, 4Iowa State University, Ames, IA, USA, 5Aarhus University, Aarhus, Denmark, 6University of
Iceland, Reykjavik, Iceland1*corresponding author: reynoldsd3@cardiff.ac.uk

Despite numerous lines of evidence there is still a great deal of uncertainty surrounding ourunderstanding of what drives variability in the Atlantic Meridional Overturning circulation (AMOC)
and what influence this variability has on the wider climate system. Here we present analyses ofannually-resolved absolutely-dated sclerochronological records spanning past centuries to millennia,
from across the western British Isles and north Iceland, along with the PMIP3 (Paleoclimate Model
Intercomparison Project phase 3) last millennium climate model simulations, to provide novel
insights into past AMOC variability. In contrast to recent AMOC records, these data highlight there
is significant multi-decadal to centennial scale variability in AMOC strength throughout the last
millennium and that a subtle reduction in AMOC strength was likely a driving force behind thetransition between the Medieval Climate Anomaly-Little Ice Age transition (along with solar andvolcanics). These data further suggest that a significant proportion of AMOC variability is externallyforced. This work highlights the potential power of large spatial networks of sclerochronologicalrecords and proxy-model integrated approaches at reconstructing and understanding past ocean
variability. These approaches will help to constrain uncertainties in the numeric climate models andultimately facilitate more accurate predictions of future climate variability.

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4th International Sclerochronology Conference, ISC 2016

Annually-resolved North Atlantic marine climate over the last
millennium: The ULTRA seriesDavid Reynolds1, James Scourse2*, Paul Halloran3, Sandra Nederbragt1, Alan
Wanamaker4, Paul Butler2, Christopher Richardson2, Jan Heinemeier5, Jón Eiríksson6,
Karen Luise Knudsen5, Ian Hall1
Cardiff University, Cardiff University, Cardiff, Wales, UK, 2Bangor University, Bangor, Wales, UK, 3Exeter University,
Exeter, England, UK, 4Iowa State University, Ames, IA, USA, 5Aarhus University, Aarhus, Denmark, 6University of
Iceland, Reykjavik, Iceland1*corresponding author: j.scourse@bangor.ac.uk

Numerical climate models predict a significant weakening (~30%) in Atlantic Meridional
Overturning Circulation (AMOC) over the 21st century in response to anthropogenic climate
forcings. However, the lack of absolutely dated oceanographic information prior to the modern
instrumental period limits the direct assessment of the mechanistic role played by North Atlantic
Ocean dynamics in previous climate transitions (e.g., Medieval Climate Anomaly-Little Ice
Age, MCA-LIA). Here we present analyses of the first millennial-length, annually resolved andabsolutely-dated marine archive from the ocean (ULTRA series). Our record of oxygen isotope ratios
in the shell of the long-lived marine bivalve Arctica islandica (δ18O-shell) from the North Icelandic
shelf demonstrates that solar and volcanic forcing coupled with ocean circulation dynamics are
key drivers of climate variability. This absolutely-dated series from the North Atlantic provides theopportunity for comparisons with annually-resolved Northern Hemisphere atmospheric series (treerings, ice cores) and provides a key, and unique, observational dataset for integration with coupled
ocean-atmosphere model simulations.

885th-9th June, 2016 • Portland, Maine, USA

Geochemical and crystallographic study of two species of coolwater bivalves (Fulvia tenuicostata and Soletellina biradiata)from southwestern Australia
Liza M. Roger1*, Annette D. George2, Jeremy Shaw1, Robert D. Hart1, Aaron Dodd1,
Malcolm Roberts1, Thomas Becker1, Noreen Evans3, Brad McDonald3
University of Western Australia, Centre for Microscopy, Characterisation and Analysis, Crawley, WA, Australia,
University of Western Australia, School of Earth and Environment, Crawley, WA, Australia, 3John de Laeter Centre,
TIGeR, Curtin University, Bentley, WA, Australia
12*corresponding author: liza.roger@reasearch.uwa.edu.au

This multi-modal study focuses on the structure and composition of two species of marine bivalvesendemic to southwestern Australia (Fulvia tenuicostata and Soletellina biradiata) to gain insight
into the physio-chemical processes involved in molluscan calcification and provide a benchmark
for monitoring global change in biogenic carbonate. Such studies of temperate Australian marine
bivalves are few despite the absence of coral and the need to use other faunal records. X-ray
diffraction and Raman spectroscopy analyses reveal that the shells of both species are composed
mainly of aragonite with minor calcite and not purely aragonitic as previously documented. Ionic
substitution of Mg2+ for Ca2+ is identified in calcite in F. tenuicostata and anisotropic distortions(stretching and shrinking) are consistent with other molluscan species. Electron probe microanalysis
and laser ablation mass spectrometry reveal correlations between Mg, S and P in F. tenuicostata,and Sr, S and Ba in S. biradiata. These results may give insight into the composition of the organic
matrix and its impact on elemental composition of the crystalline structure. The combination ofP- and S-containing organic macromolecules appears to be facilitating Mg2+ substitution in calcite,which might also explain greater lattice distortion in F. tenuicostata. The organic macromoleculesthat constitute the organic shell matrix require further investigation. Although the study of traceelement incorporation in biogenic carbonate is important, the composition of the organic molecules
is also significant considering it may exert a control on the fine-scale composition and structure ofbivalves and other biogenic carbonate.

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4th International Sclerochronology Conference, ISC 2016

Advances in developing Antarctic sclerochronogical archives
from the marine bivalve Yoldia eightsi
Alejandro Román González1*, Ian Hall1, James Scourse2, Paul Butler2, Caroline Lear1,
Lloyd Peck3, Martin Ziegler4
Cardiff University, Cardiff University, Cardiff, Wales, UK, 2Bangor University, Bangor, Wales, UK, 3British Antarctic
Survey, Cambridge, England, UK, 4Utrecht University, Utrecht, Netherlands
1*corresponding author: Roman-GonzalezA@cardiff.ac.uk

A strong warming trend in west Antarctic has been measured over at least the last 50 years, this isassociated with a shortening of the winter season, increased deglaciation and meltwater runoff andwarming and freshening of surface waters. These environmental responses are very likely to affect
Antarctic ecosystems from shallow habitats to deeper communities. However, investigation of thesechanges is limited because of a lack of long-term environmental records endemic for Antarctica
due to the isolation of the continent and for technical and economic reasons. Annually-resolved
sclerochronological archives have now the potential to fill some of the gaps in the instrumental
record and even to extend back beyond the establishment of the scientific stations. Yoldia eightsi
is an infaunal marine bivalve found in shallow waters (mostly down to 100 m) and it is believed tohave a circum-Antarctic distribution. We present five chronologies from two Antarctic locations:South Orkney Islands (Signy station) and West Antarctic Peninsula (Rothera station). Yoldia eightsi
shell growth showed a negative relationship with winter duration (r = -0.52, N=24, P≤ 0.01) andfast-ice duration (r = -0.41, N= 24, P≤ 0.05) and a positive relationship with mean annual sea surface
temperature (SST; r = 0.48, N= 24, P≤ 0.05) winter SST (r = 0.57, N= 24, P≤ 0.01) and summer SST(r = 0.46, N= 24, P≤ 0.05) between 1965 and 1988 at Signy. Chronologies developed from adjacentsampling locations at Rothera may offer insights into the local hydrography.

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5th-9th June, 2016 • Portland, Maine, USA

Bivalve Sr/Ca(shell) heterogeneity and microstructures –Are geochemical variations at the micrometer-scale masking
potential environmental signals?
Bernd R. Schöne1*, Christoph S. Füllenbach1, Liqiang Zhao1, Stefania Milano1, Regina
Mertz-Kraus1, Kotaro Shirai2, Naota Takahata2, Akizumi Ishida2, Yuji Sano2
Institute of Geosciences, University of Mainz, Mainz, Germany, 2Atmosphere and Ocean Research Institute, Universityof Tokyo, Tokyo, Japan1*corresponding author: schoeneb@uni-mainz.de

It is still controversially debated if the trace and minor elements of (aragonitic) bivalve shells serve as
environmental proxies or largely reflect changes in bivalve physiology and/or crystal kinetics. For example, incontrolled tank experiments, Sr/Ca ratios in shells of Corbicula fluminea are positively and linearly correlated
to Sr/Ca of the ambient water and negatively to temperature (Zhao et al., 2016) – which is in agreement withabiogenically precipitated aragonite. However, the Sr/Ca(shell) values remain ca. four times below that of
Sr/Ca(water), and the temperature sensitivity is only -0.02 mmol/mol/1°C as opposed to -0.04 in synthetic
aragonite (Dietzel et al., 2004) and, on average, -0.06 in tropical, shallow-water corals (Corrège, 2006). In
wild populations of many other bivalve species, distribution coefficients also deviate significantly from thatof abiogenic aragonite suggesting that Sr is not incorporated into the crystal lattice of CaCO3 in equilibriumwith the ambient water. Furthermore, Sr levels near annual growth lines were much higher than in portions
between adjacent growth lines (= growth increment), yet lower than those expected for chemical equilibrium.
Surprisingly, no uniform temperature sensitivity seems to exist in wild-grown bivalves, and some authors
were unable to identify any clear relationship between Sr/Cashell and temperature.
To study what these discrepant findings may explain, we have conducted an ultra-high resolution
mapping (electron microprobe, NanoSIMS) of strontium and sulfur (as a proxy for certain organics) inshells of Cerastoderma edule collected alive from the intertidal zone of the North Sea. Sr levels werestrongly heterogeneously distributed at the lower micrometer scale and strongly coupled to the prevalentmicrostructure (crystal fabrics, shell ultrastructure). In the outer portion of the outer shell layer for example,
Sr/Ca ratios were significantly higher at circatidal growth lines (irregular simple prismatic structure; 2.9 ±0.4 mmol/mol) and lower within circatidal increments (nondenticular prismatic structure; 2.5 ± 0.2 mmol/
mol). Shell sulphur-to-calcium ratios showed the opposite distribution patterns, i.e., high values in circatidal
increments (2.4 ± 0.3 mmol/mol), low values at circatidal growth lines (2.1 ± 0.5 mmol/mol). Both Sr/
Ca(shell) and S/Ca(shell) were at maximum values at annual growth lines (4 and 4.6 mmol/mol, respectively).
The intimate link between Sr/Ca(shell), S/Ca(shell) and shell architecture likely indicates that microstructuresor the processes controlling their formation exert a strong control over the incorporation of strontium intoshells of C. edule. Analytical techniques with lower sampling resolution, e.g., LA-ICP-MS, cannot resolve
such fine-scale Sr variations. As a result, the signal-to-noise ratio decreases and the data generated by suchtechniques do not seem to provide useful paleotemperature data. Future studies should therefore employ a
combined analysis of Sr/Ca(shell) and shell microstructures. Sr/Ca(shell) values of shell portions consisting ofdifferent microstructures should be interpreted separately.

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Spatial distribution of low molecular weight organic matter in
micrometer skeletal structure of Acropora and Porites coral
Kohki Sowa1*, Akira Ijiri2, Satoko Motai3, Fumio Inagaki2, Kosei E Yamaguchi1
Toho University, Funabashi-shi, Japan, 2JAMSTEC, Yokosuka, Japan, 3AORI, The University of Tokyo, Japan,

1*corresponding author: kouki.sowa@sci.toho-u.ac.jp

Coral skeletons consist of aragonite and organic matter (1–3 wt%) (e.g. Falini et al., 2014).
Microstructures in coral skeletons comprise two microstructural components: centers of calcification(COC), and fibers (>96 vol%) (Allison, 1996). Previous studies have focused on elemental
distribution (e.g., S, Sr, δ11B, and δ18O) in coral microstructures. Although organic matter is one of
the important chemical components for coral biomineralization, only few studies have examined
its distribution in micrometer skeletal structure (e.g. Cuif et al., 2005; Mass et al., 2014). The
information will resolve the enigma of forming different crystallographic texture of COCs and fibers.
Here, we report the first result of the spatial distribution of low molecular weight organic matter(m/z 100–1500) in coral skeletal microstructures using matrix-assisted laser desorption/ionization
MS imaging by iMScope TRIO (Shimzau Corporation) at JAMSTEC, Japan. We used branching
Acropora sp. and massive Porites sp. skeletons, collected from Okinawa and Kagoshima, Japan,
for the analysis. Coral skeletons were immersed in hydrogen peroxide and sodium hypochlorite
solutions to remove coral tissues and organic matters on the surface of coral skeletons. After washing
the coral samples via MQ, the samples were embedded in epoxy resin (E205, Nichika.Co.Ltd,
Japan). Thin sections of <0.1 mm thickness were then prepared. A matrix of 2,5-dihydroxybenzoic
acid (DHB) was vapor-deposited onto the thin section. Measurement pitch and laser diameter ofthe iMScope were set at <5 μm. Except for the strong peak of resin and glue, specific peaks foreach coral specimen were different. The prominent peaks below m/z 450 were observed in positive
ion mode for Acropora coral specimens. On the other hand, prominent peaks at m/z 300–900 andm/z 650–900 were observed in positive and negative ion modes, respectively, for Porites coral
specimens. There were no distinct differences observed between COC and fibers in both coral types
examined. Further results will be discussed regarding the m/z and composition of organic matter.

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Tides & traditions: Insights into indigenous hunter-fishergatherer shellfishing with sclerochronology
Anna Sparrow1*, Natasha Leclerc1, Meghan Burchell1
Memorial University, St. John’s, NL, Canada

1*corresponding author: ajs644@mun.ca

Hunter-fisher-gatherers on the Pacific Northwest Coast of North America are renowned for theircomplex fishing strategies that sustained a storage-based economy for over 6000 years. However, therole of shellfish has often been overlooked in archaeological interpretations. Hunter-fisher-gatherers
living on coastal landscapes incorporated shellfish into their diets throughout the course of humanhistory, and in turn, shellfish became incorporated not only as a dietary staple but also as a culturally
significant component of their everyday lives. Shellfish were gathered for consumption, constructionof shell middens, creation of artifacts, and have been included in many oral traditions, myths, songs,
and dances.
Using macro-growth line analysis, the deliberate management of butter clam (Saxidomus gigantea)
has been identified on the central coast of British Columbia in the traditional territory of the HeiltsukFirst Nation. In addition, ‘clam gardens’ have also been identified in several regions of the PacificNorthwest Coast, providing further evidence for sophisticated intertidal resource management. Thereis a saying amongst the Tlingit of Alaska and northern British Columbia that ‘When the tide is out,
the table is set’ – in this poster, we explore traditional myths, stories, songs, and art to investigate
the cultural significance of shellfish to the peoples on the Pacific Northwest Coast. Integratingsclerochronological analysis alongside Indigenous knowledge and tradition can help to refinearchaeological understandings of past shellfish use and the continuity of shellfish harvesting over
Holocene.

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Determining season of harvest in shells of the European limpet(Patella vulgata) from modern and medieval collections
Donna Surge1*, James H. Barrett2
University of North Carolina-Chapel Hill, Department of Geological Sciences, Chapel Hill, NC, USA, 2McDonald
Institute for Archaeological Research, University of Cambridge, Cambridge, UK

1*corresponding author: donna64@unc.edu

Shells of the European limpet, Patella vulgata, are common constituents in late Holocene
archaeological middens along eastern North Atlantic coastlines. Thus, they potentially serve as
valuable records of paleoclimate information and human activity. Oxygen isotope sclerochronology
is a powerful tool for deciphering seasonal changes in growth temperature (a proxy for seawatertemperature) and season of death. A previous calibration study on modern P. vulgata demonstrated
its utility for reconstructing seawater temperature after correcting for a predictable offset fromoxygen isotope equilibrium. Ultra high-resolution microsampling of P. vulgata shells at submonthly
scale can potentially capture the entire range of seasonal variability assuming growth rates
are greater than 1 mm per year. Using isotope sclerochronology, we evaluate the potential ofarchaeological P. vulgata shells to accurately record information on season of harvest. Modern shells
were collected alive from Rack Wick Bay off Westray in the archipelago of Orkney, Scotland on 16
August 2006, the warmest month of the year, and eight were selected for isotopic analysis. Five of
the modern shells recorded actual seawater temperature at the time of harvest within error, and six
shells reflected summer season along the growth margin. Estimated temperature along the growthmargins of the other two shells were more similar to mid-spring temperature, likely reflecting a timeaveraging bias due to slowed growth with increasing ontogenetic age. Therefore, it is critical to take
growth rate into account when estimating season of harvest. Ten archaeological shells from a nearby
midden dating to the 12th Century were selected for isotopic analysis, and all specimens had wellpreserved margins that lacked signs of abrasion. Estimated temperature from oxygen isotope ratios
recorded in the last year of growth suggest harvesting occurred year round.

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Reconstruction of humpback whale migration via isotopic
analysis of coronulid barnacle shells
Larry Taylor1*, Seth Finnegan1
University of California at Berkeley, Berkeley, CA, USA1*corresponding author: larry.taylor@berkeley.edu

The ecology of the modern great whales is defined by migration, as their immense nutritional needs
demand that they traverse thousands of miles to reach the seasonally productive waters on which
they rely. Understanding the impact that external pressures have had on migratory behaviors throughtime would offer new insight into cetacean natural history, yet little is known about whale migration
prior to the advent of whaling. A potential proxy for reconstructing whale migration may be found,however, within the calcitic shells of coronulid barnacles (Killingley, 1980). Coronulids – the epizoic
crustaceans which live attached to baleen whales – grow their shell plates in measureable daily
increments that are each deposited in isotopic equilibrium with the surrounding seawater. Thus abarnacle attached to a migrating whale will preserve within its shell growth bands a high-resolution
isotopic signature of the water through which the whale was moving, with progressive changes inoxygen-18 values largely reflecting changes in latitude. Here we present initial isotopic analysis ofcoronulid shells collected from humpback whales stranded on the coast of California. Eastern Pacificseawater isotope and temperature gradients were used in conjunction with the shell oxygen isotope
ratios to interpret the movement of the barnacles’ cetacean hosts. Preliminary results indicate that thehost whales wintered in waters south of Baja California and migrated to northern California to feedin the summer, a trajectory consistent with the migration patterns of California coast humpbacks.
Application of this method has potential use as a means of reconstructing cetacean migration in bothmodern oceans and in the prehistoric past, allowing us to pursue questions of how previous changes
in climate, ocean nutrient distribution, or other extrinsic pressures may have impacted cetacean
migratory behavior.

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Growth, longevity and stable isotope composition of European
date mussels Lithophaga lithophaga from eastern Adriatic
Melita Peharda1, Sanja Puljas2, Laurent Chauvaud3, Bernd Schöne4, Daria Ezgeta-Balić1,
Julien Thébault5*
Institute of Oceanography and Fisheries, Split, Croatia, 2Faculty of Science, University of Split, Croatia, 3Université deBrest - CNRS, Plouzané, France, 4Institute of Geosciences, University of Mainz, Mainz, Germany, 5Université de Brest,
Plouzané, France

1*corresponding author: julien.thebault@univ-brest.fr

Bivalve mollusc shells are widely used as archives of past variability in aquatic environments. Longlived species are particularly useful for long-term reconstructions of climatic and environmental
signals over decades to centuries. However, most of these species are living in cool marine waters
under temperate settings. No equivalent of northern quahogs Arctica islandica (>500 years old)or dog cockles Glycymeris glycymeris (>200 years old) has ever been found in the Mediterranean.
The European date mussel Lithophaga lithophaga (Mytilidae) is an endolithic bivalve species
boring into calcareous substrates all around the Mediterranean coasts. Although under-investigated,
this protected species (listed in the CITES Appendix II) has been suggested to live more than 50
years in the Aegan Sea, and therefore appears as a good candidate for paleo-ecological and paleoenvironmental studies.
Here, we analyzed shell growth of 71 specimens collected in July 2013 off Split (Croatia) bycounting ridges on the external shell surface. High variations in growth rates between individuals
were noted and age of analyzed shells (based on the assumption of an annual periodicity offormation of external ridges) varied from 10 to 54 years (for a shell length of 30.6 to 93.6 mm).
According to results of growth modelling using a generalized von Bertalanffy growth function,
asymptotic shell length was 107.6 mm while growth coefficient was 0.03 year-1. Both parameters
were used to calculate an overall growth performance index that was found to be similar to the one
previously calculated in a Greek date mussel population (2.54 vs. 2.42, respectively). In addition,
we analysed the oxygen and carbon isotope composition of one shell, randomly selected amongst
medium-sized shells. A total of 147 discrete carbonate samples were collected on the shell surface
using a micromilling device (2-8 samples per growth increment). Obtained δ18O results strongly
suggest that growth ridges visible on the external shell surface of L. lithophaga are formed annually
as we counted as many growth increments as δ18O cycles. The δ18O values ranged from -0.2 to 2.7‰, which equates to a temperature range of 13°C. The reconstructed seawater temperatures varied
from 12 to 25ºC, a range in good agreement with measured temperature. Stable carbon isotope
values decreased through ontogeny and ranged between -2.05 and 2.32‰. Results of this study
provide first stable isotope data for Lithophaga lithophaga shells and show potential of this species
as geochemical sclerochronological archive.

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Great scallop shells as geochemical archives of phytoplankton
dynamics in the Bay of Brest (France)
Julien Thébault1*, Aurélie Jolivet1, Sophie Sabarot1, Hélène Tabouret2,
Matthieu Waeles1, L’Helguen Stéphane1, Aude Leynaert1, Christophe Pécheyran2,
Laurent Chauvaud1
Université de Brest - CNRS, Plouzané, France, 2Université de Pau et des Pays de l’Adour - CNRS, Pau, France

1*corresponding author: julien.thebault@univ-brest.fr

It is now widely accepted that human activities affect the structure and functioning of coastal
ecosystems. One of the most significant consequences are related to changes in nutrient input that
can induce changes of trophic conditions (up to eutrophication) and disturbances of phytoplankton
dynamics, keystone of the functioning of coastal ecosystems. This includes changes in primary
production levels, in bloom frequency, and in the composition of microalgal communities.
However, this global outlook conceals major temporal and spatial disparities. As conventional
monitoring time-series are quite sparse and scattered, biological records of environmental variability
are relevant tools to gain insight into phytoplankton dynamics over larger temporal and spatial
scales. In this context, bivalve mollusk shells, and especially scallops (Pectinidae), appear as
valuable biogenic archives as they form their external calcium carbonate skeleton periodically,leading to the formation of concentric growth lines that can be used as chronological landmarks.
Here, we present results of a interdisciplinary project dealing with geochemical information archived
in shells of the great scallop Pecten maximus in the Bay of Brest (France). This species is known
to form daily growth lines between March and November visible on its calcitic shell surface. An
extensive 1-year environmental survey of physical, chemical and biological parameters was carriedout in 2011 with a weekly resolution, at the exact location of a large scallop population. Several
scallops were then collected at the end of this survey and analyzed for their shell geochemicalcomposition. We focus here on results dealing with lithium and molybdenum concentration ofseawater, soft tissues and shells.
Our results highlight that phytoplankton dynamics can explain the incorporation of these elements
in shells, both through trophic (Mo) and dissolved (Li) pathways, that can in turn be used as proxies
and archives for ecological processes in coastal waters.

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Environmental variability revealed in sclerochronologicalrecords of Arctica islandica from the northern North Sea
Tamara Trofimova1*, Carin Andersson1, Fabian Bonitz1
Uni Research Climate, Bjerknes Centre for Climate Research, Bergen, Norway

1*corresponding author: tamara.trofimova@uni.no

The shortness of the instrumental records and the lack of high resolution marine paleo records
limit our understanding of climate dynamics and climate change in the North Sea. For extratropicalmarine reconstructions bivalves have been shown to provide a useful archive with high temporal
resolution. The species, Arctica islandica is unique due to its exceptional longevity combined withsensitivity to changes in environmental conditions. It also has a wide geographical distribution, andprevious investigations have successfully shown that sclerochronological records of this species
from both sides of the North Atlantic can be used for the climatic reconstructions.
In this study we investigate the impact of climate variability on sclerochronological records of A.
islandica from the northern North Sea - the major gateway for the inflow of Atlantic water in the
North Sea. We use shells of A. islandica collected by dredging along the seabed on the Viking Bank
(North Sea) at depth around 100 meters. The growth patterns of living and subfossil specimens
were analysed using acetate replicas made from polished and etched cross-sections of individual
shells. The annual growth bands were determined and growth increments widths were measured.
By cross-matching 28 individual increment-width time series we build an absolutely dated 187year long shell-growth chronology. The relatively high Rbar (>0.5) and EPS (>0.85) values suggest
strong environmental forcing on the shell growth within the population. Therefore, ongoing work
mainly focuses on comparing the shell-growth chronology with existing observational time seriesof climatic parameters to determine controlling factors and test the use of growth chronologies forclimate reconstruction in this area. For reconstructing seasonality we analyse the stable isotope(δ18O, δ13C) composition of the shell carbonate by milling individual growth increments. Future work
includes the development of an annually resolved oxygen isotope record and subsequent temperaturereconstruction.

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Low-frequency variability in a centennial-length biochronology
of Bering Sea Pacific ocean perch (Sebastes alutus)
Peter van der Sleen1*, Matthew Dzaugis1, Christopher Gentry2, Wayne Hall1, Vicki
Hamilton3, Thomas Helser4, Mary Matta4, Christopher Underwood5, Rachel Zuercher6,
Bryan Black1
Marine Science Institute, University of Texas at Austin, Port Aransas, TX, USA, 2Department of Geosciences, Austin
Peay State University, Clarksville, TN, USA, 3Institute for Marine and Antarctic Studies, University of Tasmania, Hobart,
TAS, Australia, 4Resource Ecology and Fisheries Management Division, Alaska Fisheries Science Center, NOAA, Seattle,
WA, USA, 5Department of Geography, University of Wisconsin-Platteville, Platteville, WI, USA, 6Department of Ecology
and Evolutionary Biology, University of California, Berkeley, CA, USA1*corresponding author: j.p.vandersleen@gmail.com

Productivity and functioning of Bering Sea marine ecosystems are tightly coupled to decadal-scale
environmental variability as exemplified by the profound changes in community composition that
followed the 1976/77 shift from a cool to a warm climate regime. Longer-term ecosystem dynamics,
including the extent to which this regime shift was exceptional in the context of the past century,
remain poorly described due to a lack of multi-decadal biological time series. To address thisissue, we applied dendrochronology (tree-ring science) techniques to the otolith growth-increment
widths of Pacific ocean Perch (Sebastes alutus; POP) in the eastern Bering Sea. Two chronology
development techniques were applied: i) a regional curve standardization (RCS) approach designed
to retain as much low-frequency variability as possible, but at the expense of adding uncertainty, andii) a “negative exponential” approach that maximized ability to detect interannual variability. The
RCS chronology spanned the years 1923–2006, significantly (p < 0.001) and positively correlatedwith sea surface temperature, and was characterized by a profound, sustained shift from relatively
slow to relatively fast growth beginning at 1976/77. The years following 1976/77 were characterized
by the highest levels of growth on record, which was corroborated by the negative exponential
chronology. Ultimately, these chronologies underscore the susceptibility of fish biology to extreme
and uncommon low-frequency events, and provide clues on how future global warming may alter
growth rates of POP.

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The Mediterranean Sea during the Pleistocene – bivalve shells
and their potential to reconstruct decadal and seasonal climate
signals of the past
Gotje von Leesen1, Lars Beierlein1, Daniele Scarponi2, Bernd R. Schöne3*,
Thomas Brey1
Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany, 2University of
Bologna, Italy, 3University of Mainz, Mainz, Germany
1*corresponding author: schoeneb@uni-mainz.de

Understanding the climate of the past, in particular seasonal temperature amplitudes, is essential
to evaluate the effects of future climate change on marine ecosystems. The Mediterranean is ofparticular importance, because of its crucial role in modern ocean atmosphere phenomena such as
the North Atlantic Oscillation (NAO). We analyzed fossil shells of the bivalve Arctica islandica
collected from Pleistocene successions in Central and Southern Italy (i.e., Rome, Lecce andSicily). According to preliminary biostratigraphic data the studied deposits belong to the middle
Calabrian, between 1.2-0.9 Ma for the Sicily outcrop and 1.4-1.2 Ma for the Rome and Lecce
outcrops. Prior to isotope geochemical analysis confocal Raman microscopy measurements wereconducted to detect potential diagenetic alterations (e.g., from aragonite to calcite). The seasonal
water temperature amplitude was reconstructed using stable oxygen isotope (δ18O) values, whichwere derived by micro-milling and Isotope Ratio Mass Spectrometry. Analysis of the growth patterns(on-going research) revealed ontogenetic ages of up to 210 years. These time series are used forthe identification of multi-year (i.e., decadal) patterns, such as the NAO. First results of our study
indicate that seasonality was remarkably low during the studied geological epoch. This is in sharp
contrast to previous assumptions according to which the simultaneous occurrence of boreal (A.
islandica) and warm-water species in the Mediterranean Sea during the Pleistocene can be explainedby high seasonality. Different links and scenarios on a regional as well as a bigger scale will be
discussed.

1005th-9th June, 2016 • Portland, Maine, USA

Do oxygen isotope ratios in unionid shells reflect continental
African hydroclimate variability?
Daan Vanhove1*, David Gillikin2, Lauren Graniero3, Holly Havel2, Zita Kelemen1,
Steven Bouillon1
Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium, 2Department of Geology, Union
College, 807 Union St., Schenectady, NY 12308, 3University of North Carolina, Chapel Hill, NC, USA1*corresponding author: daan.vanhove@kuleuven.beFreshwater bivalves (unionids) are ubiquitous in many different types of river ecosystems. In
their shell carbonate, in situ changes in riverine stable isotope signatures and element abundances
are recorded. Microsampling of the growth increments in the shells allows high-resolution
reconstruction of intra-annual changes in ambient river water geochemistry. Our study evaluates
if the oxygen isotope composition in unionids can be used as proxy for variability and changes inAfrican river hydrology and precipitation, on a local to continental scale. Between 2010 and 2015,
bivalve specimens were collected from various rivers and small lakes across the African continent(Niger, Mali, Central African Republic, D.R. Congo, Kenya, Botswana, Zimbabwe, Namibia,
and South Africa). Oxygen stable isotope ratios in the shells (δ18Oshell) were measured in order toreconstruct those in ambient water (δ18Owater). Values are compared to a published model of isotopes
in precipitation (δ18Oprecipitation), and to measured δ18Owater at monitoring stations (GNIP and GNIR
data from the IAEA, Vienna; own data). A continental-scale isoscape of the amplitude of δ18Oshell
was constructed and evaluated against amplitude of δ18Oprecipitation. We find that the amplitude ofbivalve δ18Oshell tends to correlate with the amplitude of δ18Oprecipitation along a cross-continental
transect through sampling locations. Intra-annual variability of δ18Oshell in central Africa is relatively
low, between -4.0 ‰ and -2.0 ‰ around the equator and between -4.0 and 0.0 ‰ at 5° N. Towards
southern Africa, the seasonal range increases to 6.9‰, reflecting both temperature and δ18Owater variability. By contrast, specimens from Niger show a 12‰ range, from -8.0 to +4.0‰, andspecimens from an ephemeral lake tributary in Mali show previously unrecorded δ18O values ranging
up +11.3‰, reflecting contrasting humidity and highly evaporative conditions. Positive departuresfrom δ18Oprecipitation reflect evaporation during dry season (Sahel region) or lake evaporation (e.g. Nile
downstream Lake Victoria). Small negative departures probably relate to rainfall quantity duringwet-season (tropics). Secondly, we find that shell δ18O accurately reflects river water δ18O andcan be used to quantitatively reconstruct periods of low discharge (<6000 m³s-1) and qualitatively
reconstruct periods of high discharge, if the relationship between river δ18O and discharge is known.
Our data provide evidence that freshwater bivalve δ18O is an extremely valuable proxy for thereconstruction of local to continental-scale variability in African hydroclimate.

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Short-term climate variability in Central Europe during the
Oligocene – A story told by glycymerids
Eric Otto Walliser1*, Bernd R. Schöne1
Institute of Geosciences, University of Mainz, Mainz, Germany

1*corresponding author: walliser@uni-mainz.de

The Oligocene was a geological epoch during which dramatic changes occurred in the Earth system,
amongst others the onset of the Antarctic glaciation that gave rise to the present Icehouse world
climate, and the largest extinction event of the Cenozoic, the Grande Coupure. The present study
used shells of Glycymeris planicostalis and G. obovata from Lower (Rupelian) and Upper (Chattian)Oligocene strata of Germany and Belgium to shed light on the short-term climate variability ofCentral Europe during this time interval, an aspect, which remained poorly studied until now.
Glycymerids are one of the most common fossil bivalves of Cenozoic shallow water deposits ofEurope. Particularly during the Oligocene, they developed into thick-shelled and long-lived forms
that inhabited the coasts of epicontinental seas.
As indicated by seasonally resolved stable oxygen isotopes data, the studied bivalves grew theirshells during both seasonal extremes, whereas a growth cessation occurred in fall. Reconstructed
temperatures suggest environmental conditions similar to the modern northwestern Mediterranean,
with temperatures ranging between 10°C in winter and 24°C in summer. According to annual growth
patterns, the studied specimens lived for up to 155 year (on average, 70 years). Spectral analysesof standardized growth index chronologies revealed statistically significant signals on quasidecadal
time scales, mainly around 5 years, closely resembling the interannual frequencies of the El Niño
– Southern Oscillation. This points to an enhanced Pacific climate teleconnection to Europe during
the Oligocene. We further investigated the extent and the pathways of this teleconnection using
numerical climate models. Simulations indicate that the Aleutian Low and Icelandic Low werestronger linked with each other than today, which is likely related to a wider North Pacific Basin. As
a result European SST were stronger synchronized to the Pacific equatorial climate variability at that
time.

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Highly dynamic marine radiocarbon reservoir effect in the
Gulf of Maine since AD 1685
Alan Wanamaker1*, Erin Lower1, Nina Whitney1, Shelly Griffin1, Douglas Introne2,
Karl Kreutz2
Iowa State University, Ames, IA, USA, 2University of Maine, Orono, ME, USA1*corresponding author: adw@iastate.edu

Based on a multicentury, crossdated master shell growth chronology derived from annual increments
in Arctica islandica shells collected from the central coast of Maine in the Gulf of Maine (- 38m), we developed a continuous time-series of the marine radiocarbon reservoir effect to assess thevariability in the local marine radiocarbon reservoir offset (ΔR). Labrador Slope Water (LSW) andWarm Slope Water (WSW; derived from Gulf Stream waters) likely represent end-member source
waters to the Gulf of Maine. Based on 33 radiocarbon samples over a 250-year interval, this decadalscale record reveals abrupt and frequent changes in source waters to the Gulf of Maine. The median
ΔR value was 68 years with an average value of 77.8 ± 70 years, perhaps representing a typical
admixture of LSW and WSW in the Gulf of Maine. Maximum and minimum ΔR values were 222
years and -59 years, respectively, with a total range of 281 years. From AD 1685 to AD 1850 ΔR
values decreased gradually with decadal variability indicating a larger contribution of WSW into theGulf of Maine. After AD 1850, ΔR values increased rapidly suggesting a renewed influence of LSW
until AD 1900. From AD 1900 to AD 1935, ΔR values were generally around 100 years. Ongoingwork is investigating the potential relationships among the ΔR record in the Gulf of Maine and largescale ocean circulation dynamics in recent centuries. Finally, these results from the absolutely dated
master shell growth chronology indicate that using a constant ΔR value to constrain marine sedimentage/depth models via radiocarbon in the Gulf of Maine is invalid.

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Assessing seasonal variability and archaeological season of
harvest in north-central coastal Peru using the short-lived
bivalves Donax obesulus and Mesodesma donacium
Jacob Warner1*, Kristine L. DeLong1, David Chicoine1, Alan Wanamaker Jr.2,
Kaustubh Thirumalai3
Louisiana State University, Baton Rouge, LA, USA, 2Iowa State University, Ames, IA, USA, 3University of Texas atAustin, Austin, TX, USA1*corresponding author: j.warn.121@gmail.com

Archaeologically, bivalves provide information about not only local environment but also humanbehavior. Some long-lived bivalves (e.g., A. islandica, P. generosa, S. gigantea) have also beenused to provide paleoclimatic reconstructions as a time series of variability. However, longlived organisms are rare in coastal Peru requiring the use of short-lived organisms to reconstructseasonal variability for select time intervals. Monte Carlo simulations suggest short-lived bivalves
are better poised to record seasonal variability than single foraminifers (2–3 month life span) due
to their longer life span (1–3 years). Mesodesma donacium (a short-lived bivalve) has been used
to reconstruct season of harvest, which is crucial to understanding prehistoric human subsistencesystems, and the variability of past seasonal cycles. Studies in central and southern coastal Peru
using δ18O seasonal cycles in M. donacium reveal similar variability between modern and 2900
BP (δ18O seasonal cycle = ~1‰). However, M. donacium is vulnerable to die offs from warmer
sea surface temperatures (SST) during El Niño events, possibly biasing its seasonal δ18O cycle
towards La Niña conditions. Furthermore, M. donacium is functionally extinct north of ~14°S,
making modern calibrations biased toward colder surface waters. Lastly, spatial and temporal gaps
exist in previous reconstructions as they lack archaeological sites north of 10°S and M. donacium
specimens from 2900 to 800 BP. We assess the ability of M. donacium and Donax obesulus, a shortlived bivalve with warm water temperature preference, to record season of harvest and seasonal
δ18O variability on the north-central coast of Peru (9°11’30.38” 78°23’30.97”) in archaeological(2400 ±100 BP) and modern contexts. Initial δ18O results from an archaeological M. donacium
specimen (MA266-1) reveal a δ18O seasonal cycle of 1.1‰ confirming seasonal variability similar
to modern conditions noted by previous studies. We interpret the δ18O value from the ventral
margin of MA266-1 as austral spring (~25% of cycle) for seasonal of harvest. D. obesulus (lifespan 1–3 years) is an intertidal clam found in both modern and archaeological contexts at ourstudy site. The mean seasonal cycle of δ18O (0.9 ±0.46‰, 1σ) from 12 D. obesulus (6 modern, 6archaeological) specimens confirm this species’ ability to record seasonal cycles. Season of harvestfor modern specimens was austral winter (July 2012), but varies in archaeological specimens. D.
obesulus exhibit a -0.77‰ change in mean δ18O value (modern = 1.02‰, archaeological = -0.25‰)
suggesting a shift in salinity and/or temperature. The greater mean δ18O seasonal cycle range
recorded by D. obesulus archaeological specimens (1.6±0.5‰, 1σ, n=6) compared to previous
studies using only M. donacium (~1‰) indicates that climatic conditions ~2400 BP may havebeen more variable than previously understood. Our results confirm M. donacium’s cold bias,
necessitating combination of these two proxies for a complete picture of climate and human activity
in prehistoric coastal Peru.

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5th-9th June, 2016 • Portland, Maine, USA

An annually resolved, shell-derived oxygen isotope record since
the late Little Ice Age from the Gulf of Maine: Implications for
ocean circulation changes in the western North Atlantic
Nina M. Whitney1*, Alan D. Wanamaker1, Shelly M. Griffin1, Karl J. Kreutz2,
Douglas S. Introne2
Iowa State University, Ames, IA, USA, 2University of Maine, Orono, ME ,USA1

*corresponding author: nwhitney@iastate.edu

Recent studies have suggested that Gulf of Maine waters are warming faster than 99.9% of the
global ocean. However, despite the fact that it is one of the longest (110 years) on the east coastof North America, the instrumental record in the region is relatively short and therefore limits ourability to evaluate whether this recent warming is outside of the range of natural variability ofregional water temperatures. Additionally, the short instrumental record impedes our understandingof which major climate parameters may be influencing these changing hydrographic conditions.
In order to address these challenges in evaluating recent Gulf of Maine warming, we have developed
an annually resolved oxygen isotope (δ18O) record from the Gulf of Maine that spans the past 250
years. This record was developed from crossdated Arctica islandica shells collected in the western
Gulf of Maine in 38 meters water depth. The δ18O record has a strong inverse relationship with sea
surface temperatures (SSTs) recorded at Boothbay Harbor, Maine (~17 km distance) for the time
period during which the two records overlap (1906-2013), with 51% of the variance in the δ18O
being explained by the instrumental SST record. Therefore, δ18O from A. islandica shells appears to
be a suitable proxy for Gulf of Maine SSTs.
The δ18O record reveals that the Gulf of Maine had been cooling for the 150 years before the startof the instrumental record and that recent warm seawater temperatures are not unique in the last
250 years. This record has strong correlations with the Florida Straight (related to surface Atlantic
Meridional Overturning Circulation - AMOC) instrumental record (r = 0.92, p<.015, 4 year lag, 3-yr
running average) and modeled AMOC (r = 0.70, p<.015, 5 year lag, 3-yr running average, October)indicating that AMOC may be a primary driver of Gulf of Maine hydrographic dynamics. Therefore,
it seems likely that recent warming in the Gulf of Maine is due, at least in part, to a weakening of
AMOC strength, which may be related to anthropogenic climate change.

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4th International Sclerochronology Conference, ISC 2016

Comparing climate signals obtained from encrusting and freeliving Southwest Greenland coralline algae
Siobhan Williams1*, Jochen Halfar1, Thomas Zack2, Steffen Hetzinger3,
Martin Blicher4, Thomas Juul Pedersen4, Andreas Kronz5
University of Toronto, Toronto, ON, Canada, 2University of Gothenburg, Gothenburg, Sweden, 3Geomar, 4Greenland
Institute of Natural Resources, Nuuk, Greenland, 5Georg-August-Universität Göttingen, Göttingen, Germany

1*corresponding author: siobhan.williams@mail.utoronto.ca

Coralline algae have been widely used for sclerochronological studies throughout the last decade.
These studies have focused on two different growth morphologies of the photosynthetic coralline
algae, including massive crusts forming small buildups on hard substrate, and free-living branchingalgal nodules, known as rhodoliths. The latter are generally found on soft-substrate, where they
are frequently overturned by water movement and bottom feeding organisms, leaving one side of
the rhodolith partially buried in the sediment at any given time. The purpose of this project is totest whether one of the two growth morphologies is more suitable for proxy reconstructions. For
our test we have chosen to analyse specimens of the long-lived alga Clathromorphum compactum,
a commonly used proxy archive, from Nuuk Fjord, Greenland, which is the only location known
to date where this species forms both encrusting and free-living morphologies. In addition ,Lithothamnion glaciale, a shorter lived rhodolith proxy archive was also collected in Nuuk Fjord.
Two to three transects of laser ablation ICP-MS measured Mg/Ca ratios separated by at least 3mm
and spanning 18 years of growth were analysed on sections of two encrusting C. compactum
specimens and along different sides of five C. compactum and three L. glaciale rhodoliths. Monthly
values from multiple transects within each individual were compared and significant correlations
were found in 3 of 4 encrusting C. compactum transect comparisons, 8 of 13 C. compactum rhodolithcomparisons, and 5 of 9 L. glaciale rhodolith transects. Averaged transects from each sample werecompared with other samples of the same algal morphologies. Significant correlations were foundbetween both of the two encrusting C. compactum samples, 6 of 10 C. compactum rhodoliths, andall three of the three L. glaciale rhodoliths. Finally, all of the transects from each of the three typesof coralline algae were annually averaged and the encrusting C. compactum and L. glaciale transects
correlated significantly with a sea surface temperature record (HADSST) from Nuuk Fjord, while theC. compactum rhodolith record did not. In summary, while individual coralline algal transects showhigh intertransect and interspecimen variability, averaging of multiple records reduces variability andproduces a record more consistent with regional temperature observations.

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5th-9th June, 2016 • Portland, Maine, USA

Impact of skeletal heterogeneity and treatment method oninterpretation of environmental variability from the skeletonsof deep-sea gorgonian corals
Branwen Williams1*, Kelton McMahon2, Peter Etnoyer3, Matthew McCarthy2,
Sarah Barnes4, Andrew Walnum6, Devyn Parks4
Claremont Colleges, Claremont, CA, USA, 2University of California Santa Cruz, Santa Cruz, CA, USA, 3NOAA,Charleston, SC, USA, 4Scripps College, Claremont, CA, USA, 6Pitzer College, Claremont, CA, USA1*corresponding author: bwilliams@kecksci.claremont.edu

The proteinaceous skeletons of deep-sea gorgonian corals hold a wealth of information about pastocean conditions. These long-lived corals form hard skeletons with alternating concentric growthbands of calcite and gorgonian skeleton. They act like living sediment traps, preserving isotopic
records of their food, particulate organic matter originating in surface waters, in their skeletons.
To realize the full potential of deep-sea gorgonian corals as bioarchives of past ocean conditions,
we must better understand the preservation of isotopic signals in the coral material. Here, we use
a suite of gorgonian corals collected from four sites in the NE Pacific Ocean to quantify effectsof acidification treatment to remove the calcite skeleton and intrinsic biological variability on the
carbon and nitrogen stable isotope composition of coral tissue and gorgonin skeleton. We found thatthe stable carbon isotopic composition (δ13C) was significantly higher in acidified material due to theremoval of calcite with an isotopic composition influenced by ambient dissolved inorganic carbon at
depth. The δ13C values were significantly lower in the tissue relative to the skeleton in samples withthe calcite removed. Based on compound specific isotope analyses of the individual amino acids(AAs) in the tissue and skeleton, this difference cannot be explained by differences in the essential
and non-essential AAs δ13C values between the material types but could reflect differences in AA
composition. We found that the stable nitrogen isotopic composition (δ15N) significantly differed
between acidified and non-acidified material, indicating a pretreatment effect of acidification on thegeochemistry of the coral skeleton. With either treatment, the δ15N values were significantly lower
in the skeleton than the tissue, which reflects differences in the AA composition and their respective
isotopic signatures between the material types. The average standard deviation from the acidified
skeletons of multiple specimens located at one site was 0.9‰ for δ13C and 0.8‰ for δ15N, which issignificantly higher than typical instrumental uncertainty of ±0.2‰ reported by many stable isotope
laboratories. Taken together, these results indicate caution must be taken when interpreting the bulk
stable isotope values of coral material, particularly when comparing values across treatment methods
and material types. Quantifying these isotopic offsets inherent to the coral animals will significantly
improve our ability to interpret deep-sea coral stable isotope values as paleoproxies of past ocean
conditions.

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4th International Sclerochronology Conference, ISC 2016

Seasonal timing of shell and tissue growth in Arctica islandica
Rob Witbaard1*, Irene Ballesta Artero1, Dorothee Hippler2
Netherlands Institute for Sea Research (NIOZ), Texel, Netherlands, 2 Institut für Angewandte Geowissenschaften, Graz,
Austria1*corresponding author: witbaard@nioz.nl

The bivalve Arctica islandica is a well appreciated biochronicle on basis of which climate
reconstructions are made for the shelf seas bordering the North Atlantic. The basis of thesereconstructions are the annually deposited growth lines and growth increments.
Resolution and interpretation of these studies can be improved if there is a better understanding oftiming of shell growth, tissue growth and timing of the growth line deposition.
To obtain this knowledge, we performed a series of simple growth experiments in semi natural
conditions. In the first experiment shell size of juvenile Arctica was monthly re-measured over a
period of three years. In the second experiment shell growth, tissue growth and the period of growthline formation were estimated by monthly random sampling of specimens of which shell size was
known at the start of the experiment and of which the change in body condition could be estimatedon basis of a reference group of animals. Latter shell samples were sectioned to check in whichmonth and what percentage of animals had formed the growth line.
The results show that highest shell and tissue growth rates are found in the spring bloom and earlysummer period (March-June). In this period about 50% of the annual achieved shell growth isattained. In this period the animals obtain their highest body mass condition. The sectioning ofmonthly taken samples showed that at the end of summer (August) 100% of the animals had formed
the annual growth line.

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5th-9th June, 2016 • Portland, Maine, USA

Continuous 14C analysis of marine carbonates by laser ablation
coupled with AMS
Christiane Yeman1*, Caroline Welte1, Bodo Hattendorf2, Joachim
Marcus Christl1, Lukas Wacker1, Allen Hia Andrews3, Andre Freiwald4

Koch2,

Laboratory of Ion Beam Physics, ETH Zürich, Zürich, Switzerland, 2Laboratory for Inorganic Chemistry, ETH Zürich,
Zürich, Switzerland, 3NOAA Fisheries, Pacific Islands Fisheries Science Center, Hawaii, USA, 4Senckenberg am Meer,
Marine Research Department, Wilhelmshaven, Germany

1*corresponding author: yemanc@phys.ethz.ch

A new method for direct and continuous 14C analysis of carbonates is presented, where a laser
ablation (LA) cell is coupled to the gas ion source of an accelerator mass spectrometer (AMS). By
focusing a pulsed laser beam (ArF excimer laser 193 nm, 200 – 250 Hz) on the sample surface, CO2
is produced, which is directly and continuously introduced into the gas ion source and analyzed
for radiocarbon. A positioning system allows precise movement of the sample relative to the laser
beam. Hence, scanning along the growth axis of a sample allows recording a continuous 14C profile.
In contrast to conventional methods that require discrete sampling, such as drilling and subsequentgraphitization, minimal sample preparation is required with the novel method, thus making an
exceptional sample throughput possible. This new method is a potent tool for establishing a quick
overview of the 14C signature of a sample. Accuracies on the order of 1 % for a modern sample anda spatial resolution down to 100 µm can be achieved. The mean blank level F14C of 0.013±0.004 of
the setup is determined by scanning a marble sample, enabling to measure samples as old as 35000
years.
LA-AMS can be used for the analysis of terrestrial and marine carbonate samples, such asstalagmites, corals, shells and otoliths. Here, we present the analysis of a shell section of the species
Arctica islandica. Its 14C profile covering 50 mm could be established within 40 min. Initially it
was assumed that the shell contained the bomb 14C peak. The LA-AMS analyses revealed that theshell must be substantially older, which was afterwards also confirmed by one graphite sample.
Furthermore, the otolith of a red snapper (Lutjanus campechanus) -only a few hundred micrometers
thick- was analyzed by LA-AMS and the 14C signature recorded for the lifespan of the fish. Prebomb and peak 14C were detected, indicating the fish was more than 50 years old.

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4th International Sclerochronology Conference, ISC 2016

Effects of calcium availability on shell growth rate and element
composition of Corbicula fluminea (Bivalvia)
Liqiang Zhao1*, Bernd R. Schöne1, Regina Mertz-Kraus1
Institute of Geosciences, University of Mainz, Mainz, Germany

1*corresponding author: liqiang@uni-mainz.de

Element impurities in bivalve shells potentially record physicochemical changes of the ambientenvironment during growth. Of particular interest are divalent cations that can substitute Ca2+ inthe crystal lattice. However, the underlying mechanisms responsible for their incorporation into
the shells have not yet been fully elucidated. It is commonly assumed that Ca2+ and other divalentions may share the same transport mechanisms because of similar ionic radii and electrochemical
properties. So far, little effort has been devoted to support this hypothesis. To disentangle the roleof Ca2+ in shell formation and elemental incorporation, specimens of the Asian clam (Corbicula
fluminea) were reared for four weeks in three sets of experiments: (1) different aqueous Ca2+ levels(3, 4, 5 and 6 mM); (2) the presence of Ca2+-channel blockers (lanthanum: 1 and 10 mM; Verapamil:
0.1 and 1 mM), and (3) the presence of a Ca2+-ATPase inhibitor (ruthenium red: 0.1 and 1 mM). Ourfindings demonstrate that different Ca2+ levels in the water did not significantly affect the rate ofshell growth. Likewise, the two Ca2+-channel blockers had little effect on shell production. However,exposure to 1 mM ruthenium red led to ca. 32 % reduction of the shell growth rate. On the other
hand, with increasing water Ca2+ level, the amounts of Mn, Cu and Sr incorporated into the shells
decreased, whereas the Zn, Ba and Pb contents remained relatively constant. Blocking the Ca2+channels significantly reduced the incorporation of Mn, Cu, Zn and Pb into the shells and Mn/Cashelland Cu/Cashell decreased simultaneously when inhibiting Ca2+-ATPase. Nevertheless, neither Sr/Cashellnor Ba/Cashell were changed implying intracellular Ca2+ transport mechanisms are not responsible for
their incorporation into the shells. Findings of the present study may help to better understand themechanisms responsible for the element partitioning between the ambient water and the shells.

1105th-9th June, 2016 • Portland, Maine, USA

Index of Contributing Authors111

4th International Sclerochronology Conference, ISC 2016
A
Adey, Walter 38, 58
Affek, Hagit P. 63
Alexandroff, Stella J. 27
Ambrose, William 37, 74, 86
Andersson, Carin 33, 34, 73, 98
Andrews, Allen Hia 109
Andrus, Fred T. 28, 31
Artero, Irene Ballesta 108
Åström, Emmelie 37

B
Ballesta Artero, Irene 29
Ballew, Jared 30
Barnes, Sarah 107
Barrett, James H. 94
Bassett, Christine 31
Becker, Thomas 89
Beierlein, Lars 100
Betts, Matthew 35
Black, Bryan A. 32, 70, 82, 99
Black, Heather 28
Blicher, Martin 106
Bonitz, Fabian 33, 34, 98
Bouillon, Steven 52, 64, 101
Brey, Thomas 100
Burchell, Meghan 35, 68, 93
Butler, Paul 27, 36, 45, 46, 50, 87, 88, 90CCadrin, Steven 65
Cannon, Aubrey 35
Carroll, JoLynn 37
Carroll, Michael 29, 37, 74, 86
Chan, Phoebe 38
Chauvaud, Laurent 46, 83, 96, 97
Chenery, Simon R. 60, 81
Chicoine, David 104
Christl, Marcus 109
Clapham, Matthew 66
Cobb, Kim 21, 39

D
Das, Shibajyoti 40
Dassié, Emilie 42
Davies, Andrew 81
DeLong, Kristine L. 41, 42, 67, 104
Dietl, Greg 22

112

Dietl, Gregory 43, 44
Dodd, Aaron 89
Durham, Stephen 44
Dzaugis, Matthew 99

E
EIMF 60
Eiríksson, Jón 87, 88
Estrella-Martínez, Juan 45
Etnier, Michael A. 31
Etnoyer, Peter 107
Evans, Noreen 89
Ezgeta-Balić, Daria 96

F
Featherstone, Amy 46
Finnegan, Seth 20, 47, 95
Franceschi, Marco 66
Franco, Teresa C. B. 48
Freiberger, Megan Maria 49
Freitas, Pedro 50
Freiwald, Andre 109
Füllenbach, Christoph S. 91

G
Gaspar, Miguel 50
Gaylord, Mary Lardie 49
Geeza, Thomas 51
Gentry, Christopher 99
George, Annette D. 89
Gillikin, David 52, 53, 54, 64, 101
Goethel, David 65
González, Alejandro Román 90
Goraguer, Herlé 83
Graniero, Lauren 52, 54, 64, 101
Griffin, Shelly M. 103, 105

H
Halfar, Jochen 17, 38, 55, 58, 106
Hall, Ian 87, 88, 90
Halloran, Paul 87, 88
Hall, Wayne 99
Hamilton, Vicki 99
Harke, Ryan 56Hart, Robert D. 89
Hattendorf, Bodo 109
Havel, Holly 52, 64, 101
Heinemeier, Jan 87, 88

5th-9th June, 2016 • Portland, Maine, USA
Helmuth, Brian 19, 57
Helser, Thomas 70, 99
Herbert, Gregory 56
Hetzinger, Steffen 58, 106
Hickey, Alaina 59
Hill, Tessa M. 49
Hippler, Dorothee 108
Holdsworth, David 38
Hollyman, Phil 60
Hong, Wei-Li 37
Hussy, Karin 69

I
Ignatyev, Konstantin 60
Ijiri, Akira 92
Inagaki, Fumio 92
Introne, Douglas S. 103, 105
Ishida, Akizumi 91
Ivany, Linda C. 40, 59, 61, 63, 77

J
Johnson, Andrew 62
Jolivet, Aurélie 83, 97
Judd, Emily J. 63
Junium, Christopher K. 40, 59

K
Kelemen, Zita 52, 64, 101
Kern, Zoltán 80
Kerr, Lisa 65
Kilbourne, Kelly Hali 42
Killam, Daniel 66
Knudsen, Karen Luise 87, 88
Koch, Joachim 109
Kovach, Adrienne 65
Kreutz, Karl J. 103, 105
Kronz, Andreas 58, 106

L
LaVigne, Michèle 49, 67
Lazure, Pascal 83
Lear, Caroline 90
Lebednik, Phillip 38
Leclerc, Natasha 68, 93
Leng, Melanie 60, 62
Leynaert, Aude 97
Limburg, Karin 69
Locke, William 37
Lower, Erin 103

MMannino, Marcello A. 18, 71
Mark, Samuel 86
Markulin, Kresimir 82
Matta, Mary Elizabeth 70, 99
McCarthy, Matthew 107
McDonald, Brad 89
McMahon, Kelton 107
McNabb, Justin 72
McNichol, Ann 49
Melvik, Vilde 73
Mertz-Kraus, Regina 91, 110
Mette, Madelyn 74, 86
Mihanovic, Hrvoje 82
Miklus, Nicole M. 63
Milano, Stefania 75, 91
Miller, Hannah 49
Monteiro, Carlos 50
Morrongiello, John 23, 76
Moss, David 77
Motai, Satoko 92
Müller, Peter 78
Müller, Werner E. 75
Murray, Sean T. 78

N
Nederbragt, Sandra 88
Nederbragy, Alexandra 87
Németh, Alexandra 80
Norley, Chris 38

O
Oliver, Graham 37

P
Parks, Devyn 107
Patton, Richard 81
Payne, Taylor 28
Pécheyran, Christophe 97
Peck, Lloyd 90
Pedersen, Thomas Juul 106
Peharda, Melita 46, 82, 84, 86, 96
Poitevin, Pierre 83
Posenato, Renato 66
Puljas, Sanja 82, 96
Purroy, Ariadna 82, 84
Pyrina, Maria 85

113

4th International Sclerochronology Conference, ISC 2016
Q

U

Quinn, Terrence 41
Quintino, Victor 80

Underwood, Christopher 99

R
Retelle, Michael 74, 86
Reynolds, David 50, 87, 88
Richardson, Christopher 45, 50, 60, 81, 87, 88
Righton, David 60
Roberts, Malcolm 89
Roger, Liza M. 89

S
Sabarot, Sophie 97
Sano, Yuji 91
Savage, Julia 86
Scarponi, Daniele 100
Schöne, Bernd R. 27, 35, 45, 46, 62, 75, 84, 86, 91, 96,
100, 110
Scourse, James D. 27, 45, 50, 87, 88, 90
Shaw, Jeremy 89
Shen, Chuan-Chou 41
Sherwood, Graham 65
Shirai, Kotaro 91
Sijp, Willem P. 63
Simon, Klaus 58
Sliko, Jennifer 56
Sloane, Hilary 62
Sowa, Kohki 92
Sparrow, Anna 68, 93
Staudigel, Philip T. 78
Steinhardt, Juliane 36
Steneck, Robert 38, 58
Stéphane, L’Helguen 97
Surge, Donna 54, 62, 72, 94
Swart, Peter K. 78

T
Tabouret, Hélène 97
Takahata, Naota 91
Taylor, Frederick 41
Taylor, Larry 95
Thébault, Julien 46, 83, 84, 96, 97
Thirumalai, Kaustubh 104
Trofimova, Tamara 33, 34, 98

114

V
Valentine, Annemarie 62
van der Meer, Jaap 29
van der Sleen, Peter 32, 99
Vanhove, Daan 101
Verheyden, Anouk 53
von Leesen, Gotje 100

W
Wacker, Lukas 109
Waeles, Matthieu 97
Wagner, Sebastian 85
Walnum, Andrew 107
Wanamaker Jr., Alan D. 30, 74, 86, 87, 88, 103, 104,
105
Wang, Schunfeng 75
Warner, Jacob 104
Warner, Nathaniel 51
Welte, Caroline 109
West, Catherine F. 31
Westphal, Hildegard 78
White, Nancy 56
Whitener, Zachary 65
Whitney, Nina M. 103, 105
Williams, Branwen 42, 107
Williams, Siobhan 106
Witbaard, Rob 29, 108

YYamaguchi, Kosei E 92
Yambélé, Athanase 52, 64
Yeman, Christiane 109

Z
Zack, Thomas 106
Zemeckis, Doug 65
Zettler, Michael 72
Zhao, Liqiang 91, 110
Ziegler, Martin 90
Zorita, Eduardo 85
Zuercher, Rachel 99

5th-9th June, 2016 • Portland, Maine, USA

Sponsors

115

4th International Sclerochronology Conference, ISC 2016

IOWA STATE UNIVERSITY
Geological & Atmospheric Sciences
Changing climate, dwindling energy resources, natural
hazards, and deteriorating environmental quality are among
the most challenging of societal problems.
Geoscientists, who study Earth processes and resources tounderstand and help address these and related issues, are inhigh demand. A degree in geology or meteorology opens thedoor to career opportunities that involve:• innovative technologies• outdoor adventures and world travel• work that helps sustain society and protect the planet

Department faculty members maintainwell-funded research programs in several
focus areas:
Mesoscale/Microscale Meteorology
Hydrological Sciences
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These programs fuel discovery and provide
the basis for active graduate programs ingeology and meteorology and forundergraduate research and employment
opportunities.
253 Science I • Ames, Iowa 50011
Contact us - phone: 515-294-4477, email: geology@iastate.edu

1165th-9th June, 2016 • Portland, Maine, USA

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We can provide fast, affordable and accurate stable isotope measurements.

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515.294.6090

1174th International Sclerochronology Conference, ISC 2016

UNIVERSITY OF NORTH CAROLINA Faculty
GEOLOGICAL SCIENCES
Graduate Program

LOUIS BARTEK
Ph.D., Rice University
sedimentology, stratigraphy,
marine geology
LARRY BENNINGER
Ph.D., Yale University
low-temperature geochemistry
DREW S. COLEMAN
Ph.D., University of Kansas
isotope geochemistry, geochronology
ALLEN F. GLAZNER
Ph.D., UCLA
igneous petrology, tectonics,
geoinformatics
JONATHAN M. LEES
Ph.D., University of Washington
seismology, geophysical inverse
theory, volcanology
XIAOMING LIU
Ph.D., University of Marylandgeochemistry
LAURA J. MOORE
Ph.D., University of California,
Santa Cruz
coastal processes and geomorphology
TAMLIN M. PAVELSKY
Ph.D., UCLA
global hydrology

Our research program addresses a broad range of disciplines, which focuses on low- andhigh-temperature geochemistry, paleoclimatology, coastal processes and geomorphology,
paleobiology, geochronology, seismology, petrology, hydrology, surface processes, tectonics,
and volcanology.
Funding opportunities, made possible by the Martin endowment, include summer
stipend support for all MS and PhD students, competitive Martin fellowships, researchand travel grants, and research and teaching assistantships.
Deadline
deadline must be met to be considered for Graduate School fellowships.
Application Fee. Students with a GPA of 3.2 or higher on a 4-point scale should contact
us to inquire about eligibility for waiver of the application fee.
For more information, contact:
Deborah Harris, Student Services Specialist
University of North Carolina
Department of Geological Sciences, CB#3315
Chapel Hill, NC 27599(919) 962-0679
http://www.geosci.unc.edu

118

JOSE A. RIAL
Ph.D., California Institute ofTechnology
geophysics, climatology
KEVIN G. STEWART
Ph.D., University of California,
Berkeleystructural geology
DONNA SURGE
Ph.D., University of Michigan
paleoclimatology, paleoecology5th-9th June, 2016 • Portland, Maine, USA

Sponsor of refreshment breaks at ISC 2016

ESI provides innovative, laser-based manufacturing solutions forthe microtechnology industry

Visit ESI at http://www.esi.com/

1194th International Sclerochronology Conference, ISC 2016120

5th-9th June, 2016 • Portland, Maine, USA

Advertising Sponsors

121

4th International Sclerochronology Conference, ISC 2016122

5th-9th June, 2016 • Portland, Maine, USAC

14

The National Ocean Sciences Accelerator Mass
Spectrometry Facility (NOSAMS) operates with NSF
sponsorship at the Woods Hole Oceanographic Institution.
Investigators with U.S. federal and academic research
projects are eligible for subsidized analyses, and all
investigators studying the ocean or global change areinvited to submit samples. For information on fees,scheduling , submission and processing of samples, visit
our web site:www.nosams.whoi.edu

1234th International Sclerochronology Conference, ISC 2016124

5th-9th June, 2016 • Portland, Maine, USA

The Department of Earth Sciences at Syracuse
University is a community of scholars with diverse
interests in the nature of our planet: tectonics,
paleobiology, hydrogeology, crustal evolution,
sedimentology, isotope geochemistry, paleoclimatology,
paleolimnology, and global environmental change.
Graduate study in the Department of Earth
Sciences offers students opportunities for field andlaboratory-based geological and geophysicalresearch spanning the Earth’s deep interior,lithosphere and surface on a host of timescales.
Our faculty lead domestic and international
research programs that afford our graduate
students opportunities to work in diverse parts of
the world with teams of internationally recognizedscholars.
We offer programs leading to the Master of
Science (M.S.) and Doctor of Philosophy (Ph.D.)
degrees. Our 20-25 graduate students are typicallysupported by full-tuition scholarships and stipends
through teaching assistantships, research
assistantships, or fellowships. Typically, M.S.
students receive four semesters of support, while
Ph.D. students are eligible for eight.

Resources in-house or on campus include everything needed forsclerochronological research, including a MicroMill and prep lab,state-of-the-art facilities for analysis of light stable isotopes in bothorganic matter and mineralized tissues, radiogenic isotopes, andmajor/minor/trace element chemistry, microscopy andvisualization labs, and computational resources. Funding forstudent research and travel is available.
Research Opportunities are available in a range of fields including:
Tectonics
Hydrogeology & Hydrology
Computational Geophysics
Geomorphology
Thermochronology
Isotope Geochemistry

Paleobiology
Sedimentology
Paleoclimatology
Paleoceanography
Paleolimnology
Biogeochemistry
204 Heroy Geology Laboratory / Syracuse, New York 13244-1170

Phone: 315-443-2672 Fax: 315-443-3363 Email: earthsciences@syr.edu

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1st International
Sclerochronology Conference

St. Petersburg, Florida, USA

2nd International
Sclerochronology Conference

Mainz, Germany

3rd International
Sclerochronology Conference

Caernarfon, North Wales,
United Kingdom

4th International
Sclerochronology Conference

Portland, Maine, USA