Errata for NOAA Technical Memorandum NMFS-NE-180

1. Pg. 5, col. 2, para. 3: After “(Umminger and Mahoney 1972),” insert

“A more comprehensive analysis of Hudson-Raritan Estuary winter flounder hematological

variables (Mahoney and McNulty 1992) showed hemoglobin and hematocrit values to be

high from October to April and low from June through September; values in May were

transitional.”

2. Pg. 6, col. 1, para. 1: After last sentence, insert

“Mean MCHC in winter flounder from the Hudson-Raritan Estuary was generally higher

during the period October through April as compared to May through September (Mahoney

and McNulty 1992).”

3. Pg. 9, col. 2: After “Lux” entry, insert

“Mahoney, J.B.; McNulty, J.K. 1992. Disease-associated blood changes and normal

seasonal hematological variation in winter flounder in the Hudson-Raritan Estuary.

Trans. Am. Fish. Soc. 12:261-268.”
NOAA Technical Memorandum NMFS-NE-180

Variability in Blood Chemistry

of Yellowtail Flounder,

Limanda ferruginea,

with Regard to Sex, Season,

and Geographic Location

U. S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Northeast Fisheries Science Center

Woods Hole, Massachusetts

September 2003
155. Food of Northwest Atlantic Fishes and Two Common Species of Squid. By Ray E. Bowman, Charles E. Stillwell, William

L. Michaels, and Marvin D. Grosslein. January 2000. xiv + 138 p., 1 fig., 7 tables, 2 app. NTIS Access. No. PB2000-106735.

156. Proceedings of the Summer Flounder Aging Workshop, 1-2 February 1999, Woods Hole, Massachusetts. By George

R. Bolz, James Patrick Monaghan, Jr., Kathy L. Lang, Randall W. Gregory, and Jay M. Burnett. May 2000. v + 15 p., 5 figs.,

5 tables. NTIS Access. No. PB2000-107403.

157. Contaminant Levels in Muscle of Four Species of Recreational Fish from the New York Bight Apex. By Ashok D.

Deshpande, Andrew F.J. Draxler, Vincent S. Zdanowicz, Mary E. Schrock, Anthony J. Paulson, Thomas W. Finneran, Beth

L. Sharack, Kathy Corbo, Linda Arlen, Elizabeth A. Leimburg, Bruce W. Dockum, Robert A. Pikanowski, Brian May, and

Lisa B. Rosman. June 2000. xxii + 99 p., 6 figs., 80 tables, 3 app., glossary. NTIS Access. No. PB2001-107346.

158. A Framework for Monitoring and Assessing Socioeconomics and Governance of Large Marine Ecosystems. By

Jon G. Sutinen, editor, with contributors (listed alphabetically) Patricia Clay, Christopher L. Dyer, Steven F. Edwards, John

Gates, Tom A. Grigalunas, Timothy Hennessey, Lawrence Juda, Andrew W. Kitts, Philip N. Logan, John J. Poggie, Jr.,

Barbara Pollard Rountree, Scott R. Steinback, Eric M. Thunberg, Harold F. Upton, and John B. Walden. August 2000. v

+ 32 p., 4 figs., 1 table, glossary. NTIS Access. No. PB2001-106847.

159. An Overview and History of the Food Web Dynamics Program of the Northeast Fisheries Science Center, Woods

Hole, Massachusetts. By Jason S. Link and Frank P. Almeida. October 2000. iv + 60 p., 20 figs., 18 tables, 1 app. NTIS

Access. No. PB2001-103996.

160. Measuring Technical Efficiency and Capacity in Fisheries by Data Envelopment Analysis Using the General

Algebraic Modeling System (GAMS): A Workbook. By John B. Walden and James E. Kirkley. October 2000. iii + 15 p.,

9 figs., 5 tables. NTIS Access. No. PB2001-106502.

161. Demersal Fish and American Lobster Diets in the Lower Hudson - Raritan Estuary. By Frank W. Steimle, Robert

A. Pikanowski, Donald G. McMillan, Christine A. Zetlin, and Stuart J. Wilk. November 2000. vii + 106 p., 24 figs., 51 tables.

NTIS Access. No. PB2002-105456.

162. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments – 2000. Edited by Gordon T. Waring, Janeen

M. Quintal, and Steven L. Swartz, with contributions from (listed alphabetically) Neilo B. Barros, Phillip J. Clapham, Timothy

V.N. Cole, Carol P. Fairfield, Larry J. Hansen, Keith D. Mullin, Daniel K. Odell, Debra L. Palka, Marjorie C. Rossman, U.S.

Fish and Wildlife Service, Randall S. Wells, and Cynthia Yeung. November 2000. ix + 303 p., 43 figs., 55 tables, 3 app. NTIS

Access. No. PB2001-104091.

163. Essential Fish Habitat Source Document: Red Deepsea Crab, Chaceon (Geryon) quinquedens, Life History and

Habitat Characteristics. By Frank W. Steimle, Christine A. Zetlin, and Sukwoo Chang. January 2001. v + 27 p., 8 figs.,

1 table. NTIS Access. No. PB2001-103542.

164. An Overview of the Social and Economic Survey Administered during Round II of the Northeast Multispecies Fishery

Disaster Assistance Program. By Julia Olson and Patricia M. Clay. December 2001. v + 69 p., 3 figs., 18 tables, 2 app.

NTIS Access. No. PB2002-105406.

165. A Baseline Socioeconomic Study of Massachusetts’ Marine Recreational Fisheries. By Ronald J. Salz, David K.

Loomis, Michael R. Ross, and Scott R. Steinback. December 2001. viii + 129 p., 1 fig., 81 tables, 4 app. NTIS Access. No.

PB2002-108348.

166. Report on the Third Northwest Atlantic Herring Acoustic Workshop, University of Maine Darling Marine Center,

Walpole, Maine, March 13-14, 2001. By William L. Michaels, editor and coconvenor, and Philip Yund, coconvenor.

December 2001. iv + 18 p., 14 figs., 2 app. NTIS Access. No. PB2003-101556.

Recent Issues in This Series:
U. S. DEPARTMENT OF COMMERCE

Donald L. Evans, Secretary

National Oceanic and Atmospheric Administration

Vice Admiral Conrad C. Lautenbacher, Jr., USN (ret.), Administrator

National Marine Fisheries Service

William T. Hogarth, Assistant Administrator for Fisheries

Northeast Fisheries Science Center

Woods Hole, Massachusetts

September 2003

Renee Mercaldo-Allen1,2, Margaret A. Dawson1,

Catherine A. Kuropat1,3, and Diane Kapareiko1,4

This series represents a secondary level of scientific publishing. All issues employ

thorough internal scientific review; some issues employ external scientific review.

Reviews are -- by design -- transparent collegial reviews, not anonymous peer

reviews. All issues may be cited in formal scientific communications.

NOAA Technical Memorandum NMFS-NE-180

Variability in Blood Chemistry

of Yellowtail Flounder, Limanda ferruginea,

with Regard to Sex, Season, and Geographic Location

Postal Address: 1National Marine Fisheries Serv., Milford Lab., 212 Rogers Ave., Milford, CT 06460

E-Mail Address: 2Renee.Mercaldo-Allen@noaa.gov

3Catherine.Kuropat@noaa.gov

4Diane.Kapareiko@noaa.gov
Editorial Notes

Species Names: The NEFSC Editorial Office’s policy on the use of species names in all technical communications is

generally to follow the American Fisheries Society’s lists of scientific and common names for fishes (i.e., Robins et al.

1991aa

,bb) mollusks (i.e., Turgeon et al. 1998c), and decapod crustaceans (i.e., Williams et al. 1989d), and to follow the

Society for Marine Mammalogy's guidance on scientific and common names for marine mammals (i.e., Rice 1998e).

Exceptions to this policy occur when there are subsequent compelling revisions in the classifications of species, resulting

in changes in the names of species (e.g., Cooper and Chapleau 1998f, McEachran and Dunn 1998g).

Statistical Terms: The NEFSC Editorial Office’s policy on the use of statistical terms in all technical communications is

generally to follow the International Standards Organization’s handbook of statistical methods (i.e., ISO 1981h

).

Internet Availability: This issue of the NOAA Technical Memorandum NMFS-NE series is being copublished, i.e., as

both a paper and Web document. The Web document, which will be in HTML (and thus searchable) and PDF formats,

can be accessed at: http://www.nefsc.noaa.gov/nefsc/publications/.

a

Robins, C.R. (chair); Bailey, R.M.; Bond, C.E.; Brooker, J.R.; Lachner, E.A.; Lea, R.N.; Scott, W.B. 1991. Common and scientific names

of fishes from the United States and Canada. 5th ed. Amer. Fish. Soc. Spec. Publ. 20; 183 p.

b

Robins, C.R. (chair); Bailey, R.M.; Bond, C.E.; Brooker, J.R.; Lachner, E.A.; Lea, R.N.; Scott, W.B. 1991. World fishes important to

North Americans. Amer. Fish. Soc. Spec. Publ. 21; 243 p.

c

Turgeon, D.D. (chair); Quinn, J.F., Jr.; Bogan, A.E.; Coan, E.V.; Hochberg, F.G.; Lyons, W.G.; Mikkelsen, P.M.; Neves, R.J.; Roper, C.F.E.;

Rosenberg, G.; Roth, B.; Scheltema, A.; Thompson, F.G.; Vecchione, M.; Williams, J.D. 1998. Common and scientific names of aquatic

invertebrates from the United States and Canada: mollusks. 2nd ed. Amer. Fish. Soc. Spec. Publ. 26; 526 p.

d

Williams, A.B. (chair); Abele, L.G.; Felder, D.L.; Hobbs, H.H., Jr.; Manning, R.B.; McLaughlin, P.A.; Pérez Farfante, I. 1989. Common

and scientific names of aquatic invertebrates from the United States and Canada: decapod crustaceans. Amer. Fish. Soc. Spec. Publ. 17;

77 p.

e

Rice, D.W. 1998. Marine mammals of the world: systematics and distribution. Soc. Mar. Mammal. Spec. Publ. 4; 231 p.

f

Cooper, J.A.; Chapleau, F. 1998. Monophyly and interrelationships of the family Pleuronectidae (Pleuronectiformes), with a revised

classification. Fish. Bull. (Washington, DC) 96:686-726.

g

McEachran, J.D.; Dunn, K.A. 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs

(Chondrichthyes: Rajidae). Copeia 1998(2):271-290.

h

ISO [International Organization for Standardization]. 1981. ISO standards handbook 3: statistical methods. 2nd ed. Geneva, Switzerland:

ISO; 449 p.
Page iii

Contents

Abstract ................................................................................................................................................................................ v

Introduction ........................................................................................................................................................................... 1

Materials and Methods .......................................................................................................................................................... 1

Results ................................................................................................................................................................................... 2

Sex-Related Differences in Blood Chemistry ................................................................................................................ 2

Seasonal Differences in Blood Chemistry .................................................................................................................... 2

Location-Related Differences in Blood Chemistry as Compared to Georges Bank....................................................... 3

Discussion ............................................................................................................................................................................. 3

Seasonal and Sex-Related Differences in Blood Chemistry ......................................................................................... 3

Location-Related Differences in Blood Chemistry as Compared to Georges Bank....................................................... 6

Conclusions ........................................................................................................................................................................... 7

Acknowledgments ................................................................................................................................................................. 8

References Cited .................................................................................................................................................................... 8

Figures

Figure 1. Stations for trawl collection of adult yellowtail flounder in the Northwest Atlantic during 1978-85..................vi

Tables

Table 1. General coordinates of stations, and numbers of adult yellowtail flounder collected at those stations, during

1978-85 .............................................................................................................................................................. 11

Table 2. Pearson product moment correlations for Northwest Atlantic hydrographic conditions and blood constituent

levels in trawl-collected adult yellowtail flounder during 1978-1985 ................................................................. 12

Table 3. MANCOVA results for blood constituent levels in trawl-collected adult yellowtail flounder from the Northwest

Atlantic during 1978-1985 ................................................................................................................................. 13

Table 4. Blood osmolality in adult yellowtail flounder trawl-collected from the Northwest Atlantic during 1978-1985 .. 14

Table 5. Blood sodium concentrations in adult yellowtail flounder trawl-collected from the Northwest Atlantic during

1978-1985 .......................................................................................................................................................... 15

Table 6. Blood potassium concentrations in adult yellowtail flounder trawl-collected from the Northwest Atlantic during

1978-1985 .......................................................................................................................................................... 16

Table 7. Blood calcium concentrations in adult yellowtail flounder trawl-collected from the Northwest Atlantic during

1978-1985 .......................................................................................................................................................... 17

Table 8. Hematocrit in adult yellowtail flounder trawl-collected from the Northwest Atlantic during 1978-1985 ........... 18

Table 9. Hemoglobin concentrations in adult yellowtail flounder trawl-collected from the Northwest Atlantic during 1978-

1985 ................................................................................................................................................................... 19

Table 10. Mean corpuscular hemoglobin concentration in adult yellowtail flounder trawl-collected from the Northwest

Atlantic during 1978-1985 ................................................................................................................................. 20

Common and Scientific Names of Species Discussed

Atlantic halibut ........................................................................................................................... Hippoglossus hippoglossus

Brook trout ............................................................................................................................................. Salvelinus fontinalis

Channel catfish ........................................................................................................................................Ictalurus punctatus

English sole ................................................................................................................................................. Parophrys vetula

Eurasian perch .............................................................................................................................................. Perca fluviatilis

European flounder ...................................................................................................................................... Platichthys flesus

Lake trout .......................................................................................................................................................... S. namaycush

Largescale blackfish ..................................................................................................................................... Girella punctata

Madai .................................................................................................................................................................Pagrus major

Mummichog .........................................................................................................................................Fundulus heteroclitus
Page iv

Pinfish ................................................................................................................................................... Lagodon rhomboides

Plaice .................................................................................................................................................... Pleuronectes platessa

Rainbow trout ...................................................................................................................................... Oncorhynchus mykiss

Redear sunfish ...................................................................................................................................... Lepomis microlophus

Rock bass.............................................................................................................................................. Ambloplites rupestris

Smallmouth bass ................................................................................................................................. Micropterus dolomieu

Striped bass ................................................................................................................................................. Morone saxatilis

Striped mullet ................................................................................................................................................. Mugil cephalus

Summer flounder ..................................................................................................................................Paralichthys dentatus

Windowpane ..................................................................................................................................... Scophthalmus aquosus

Winter flounder ...................................................................................................................Pseudopleuronectes americanus

Yellowtail flounder .................................................................................................................................. Limanda ferruginea

Acronyms

MCHC .............................................................................................................. mean corpuscular hemoglobin concentration

NEFSC .............................................................................................................................. Northeast Fisheries Science Center

NEMP..................................................................................................................................... Northeast Monitoring Program

OPP ........................................................................................................................................................Ocean Pulse Program
Page v

ABSTRACT

Yellowtail flounder, Limanda ferruginea, were collected from six locations along coastal New England (i.e., Cape Cod

Bay, Georges Bank, Massachusetts Bay, mouth of the Merrimack River, Mud Patch (south of Marthas Vineyard), and New

York Bight), and were monitored for blood chemistry and hematology. Plasma osmolality, sodium, potassium, calcium,

hemoglobin, hematocrit, and mean corpuscular hemoglobin concentration (MCHC) were measured.

Osmolality and sodium concentrations were frequently reduced during spring. Potassium was generally elevated during

spring and/or summer, and reduced during fall and/or winter. Calcium was usually highest during fall. The hematological

indices of hematocrit, hemoglobin, and MCHC showed an overall elevation during winter as compared to fall. Fish from the

inshore locations of Cape Cod Bay, Massachusetts Bay, Merrimack River, Mud Patch, and New York Bight differed

significantly from fish from the offshore reference location of Georges Bank for particular blood parameters during certain

seasons.

These data provide a baseline range for blood constituents of yellowtail flounder over an annual cycle and at key

locations in the Northeast U.S. Shelf Ecosystem. These results present evidence of possible anthropogenic effects on the

blood chemistry and hematology of yellowtail flounder collected from inshore areas. Variability in blood chemistry appears

to be regulated by seasonally-induced physiological and/or environmental factors, and influenced by sex and capture

location. This information may prove to be useful in monitoring the health of field-collected yellowtail flounder and in

assessing the condition of aquacultured fish of this species.
Page vi

Figure 1. Stations for trawl collection of adult yellowtail flounder in the Northwest Atlantic during 1978-85. (Each station is

assigned to one of five inshore (Merrimack River, Massachusetts Bay, Cape Cod Bay, Mud Patch, and New York

Bight) or one offshore (Georges Bank) location.)
Page 1

INTRODUCTION

Yellowtail flounder, Limanda ferruginea, is a commercially important flatfish inhabiting Northwest Atlantic waters ranging from the Gulf of St. Lawrence to Chesapeake

Bay (Bigelow and Schroeder 1953; Collette and KleinMacPhee 2002). Evidence suggests that yellowtail flounder from Cape Cod Bay, Georges Bank, and the region encompassing Southern New England to the Mid-Atlantic

Bight represent three distinct stocks (Cadrin 2003; Cadrin

and King 2003). Yellowtail flounder are fast growing, have

high market value (Johnson et al. 1999), and have been

identified as a candidate species for aquaculture (Rabe and

Brown 2000). Despite the historical importance of yellowtail flounder as a commercial resource, relatively little information is available concerning the blood chemistry of this

species.

Blood chemistry and hematological measurements can

provide valuable tools for monitoring the health and condition of both wild and cultured fish. Physiological indices

can offer critical feedback on rearing conditions and nutritional status, and can aid in the diagnosis of disease. These

monitoring and feedback applications require an understanding of normal blood component levels specific to yellowtail

flounder, as blood chemistry concentrations are known to

vary among fish species (Larsson et al. 1976; Hardig and

Hoglund 1983; Folmar 1993). Natural changes in environmental conditions associated with season can affect blood

chemistry and hematology (Bridges et al. 1976; Warner and

Williams 1977; Lane 1979; Dawson 1990; Folmar 1993; Houston 1997; Luskova 1998; O’Neill et al. 1998; Edsall 1999).

Physiological variation in fish may be influenced by both

internal and external cues, including reproductive stage,

water temperature, dissolved oxygen, nutrient availability,

and photoperiod, all of which undergo annual cycles

(Sandstrom 1989; Dawson 1990). Seasonal changes may

also be influenced by nonenvironmental factors such as

diet, metabolic adaptations, and activity levels (Denton and

Yousef 1975).

Hematological measures, which can be affected by exposure to chemical pollutants (Heath 1995), are useful indicators of sublethal environmental stress in fish (Bridges et

al. 1976; Warner and Williams 1977; Folmar 1993). Yellowtail flounder demonstrate strong site fidelity, are found both

inshore and offshore (Royce et al. 1959; Lux 1964; Johnson

et al. 1999; Cadrin 2003; Cadrin and King 2003), and live on

or close to bottom sediments where contaminant loading

occurs. Resident bottom-dwelling organisms, such as flatfish, often exhibit environmentally-induced disease

(Ziskowski et al. 1987), making them potential indicator species for monitoring of anthropogenic effects. Before blood

constituent data can be applied as a diagnostic tool, however, general patterns related to season, sex, and collection

location need to be well documented and understood

(Bridges et al. 1976; Courtois 1976; Hardig and Hoglund

1983; Folmar 1993).

The goal of this study was to determine baseline levels

of blood parameters for yellowtail flounder. Blood chemistry and hematological measurements of osmolality, potassium, sodium, calcium, hematocrit, hemoglobin, and mean

corpuscular hemoglobin (MCHC) were determined for fish

collected from various locations in the Northeast U.S. Shelf

Ecosystem. Blood measurements were compared with regard to fish sex, season, and collection location.

MATERIALS AND METHODS

Yellowtail flounder were collected from Northwest Atlantic waters between 1978 and 1985 aboard National Marine Fisheries Service, Northeast Fisheries Science Center

(NEFSC) cruises. Nearly all fish were collected on cruises

associated with the NEFSC’s Ocean Pulse Program (OPP)

and Northeast Monitoring Program (NEMP); a few fish were

collected on cruises associated with the NEFSC’s Bottom

Trawl Survey Program. (The OPP and NEMP were the same

fundamental program; the name changed from the former to

the latter early in the effort, though.) The focus of NEMP

was assessment of ecological, genetic, pathological, and

physiological changes in coastal and shelf organisms of

the Northeast U.S. Shelf Ecosystem, which had been potentially exposed to the effects of contaminant stress (Pearce

1998).

Yellowtail flounder were collected using a “3⁄4 Yankee”

(or “No. 36") otter trawl towed for a 30-min period (Survey

Working Group, Northeast Fisheries Center 1988). Animals

were obtained from five nearshore locations, including Cape

Cod Bay, Massachusetts Bay, mouth of the Merrimack River,

Mud Patch (south of Marthas Vineyard on the continental

shelf), and New York Bight, as well as from an offshore

location, Georges Bank (Figure 1). Table 1 shows the general coordinates (i.e., latitude and longitude) of the collection stations, as well as the number of adult yellowtail flounder collected at each station. For the Georges Bank, Mud

Patch, and New York Bight locations, fish caught at adjacent stations within a given location were pooled to increase sample size for statistical analysis. Environmental

conditions (e.g., depth, substrate, temperature) at these

adjacent stations were fundamentally similar.

Fish were transferred to flowing seawater aboard ship

and processed immediately to minimize stress-induced

changes associated with capture (Larsson et al. 1976;

Wedemeyer and Yasutake 1977; Dawson 1990). Changes in

blood concentrations can occur within hours to days of

collection (Umminger 1970; Wedemeyer and Yasutake 1977;

Bourne 1986); therefore, it was critical that samples collected at sea be processed without delay. Blood was collected by cardiac puncture using a 3-ml plastic syringe with

a 22-ga needle and transferred gently into an 8-ml glass vial

coated with 150 units of dried ammonium heparin as an

anticoagulant. Hemoglobin (g/100 ml) was determined by

the cyanmethemoglobin method using Hycel reagents and
Page 2

a Bausch and Lomb Spectronic 20 spectrophotometer. (Note:

Use of trade names does not imply endorsement by NMFS.)

Hematocrit was determined by collecting blood in microhematocrit tubes, which were then centrifuged at 13,500 × g

for 5 min and read. Hematrocrit was expressed as a percentage of the volume of the whole blood sample. The remainder

of each blood sample was centrifuged at 12,000 × g, and the

resulting plasma was frozen until further analyses could be

conducted. The MCHC, the ratio between hemoglobin and

hematocrit, was expressed as g/100 ml of packed red blood

cells, and was calculated by the formula: MCHC = hemoglobin/hematocrit × 100. Plasma osmolality was determined

using an Advanced 3L or 3C2 Cryomatic Osmometer and

Advanced Instruments freezing-point calibration standards.

Sodium, potassium, and calcium (mEq/L) were determined

using a Perkin Elmer Coleman 51 Flame Photometer.

Sampling dates were assigned to a season according

to calendar designations: winter (December 22 - March

19), spring (March 20 - June 20), summer (June 21 - September 22), and fall (September 23 - December 21). Some

locations and seasons were sampled more frequently than

others because of problems often associated with extensive field sampling at sea, such as equipment failure, inclement weather, and variation in fish availability. Occasionally, a sample was not obtained for a given season.

Small sample sizes were included in a data set when information was available for other seasons at that location.

A Pearson product moment correlation was used to

determine whether hydrographic characteristics such as

temperature, salinity, and dissolved oxygen are associated

with blood chemistry values. A multivariate analysis of

variance was conducted to determine effects of sex, location, and season on osmolality, sodium, potassium, calcium,

hemoglobin, hematocrit, and MCHC. These seven blood

parameters served as the dependent variables. Independent variables for the model included sex (males and females), location (Cape Cod Bay, Georges Bank, Massachusetts Bay, Merrimack River, Mud Patch, and New York Bight),

season (winter, spring, summer, and fall), sex × location, sex

× season, and sex × location × season. Fish length was

used as a covariate. Post-hoc tests consisted of multiple

pairwise comparisons of least square means for significant

effects (P<0.05). Statistical comparisons were limited to

seasons and locations containing a sample size of N>5.

The significant differences which have been reported, but

based on small sample sizes, should be interpreted conservatively. All statistical analyses were performed using PCSAS Software Version 8.3 (SAS Institute 1989).

RESULTS

Two of the three hydrographic parameters correlated

highly with blood indices. Salinity correlated positively

with MCHC (Table 2). Dissolved oxygen correlated positively with hemoglobin and MCHC, and negatively with

osmolality and sodium. There were also relationships between certain blood parameters. Sodium correlated positively with osmolality, and negatively with MCHC. Hemoglobin correlated positively with hematocrit and MCHC. A

significant difference was observed for sex × location ×

season for all seven blood parameters (Table 3). Following

are results for differences related to sex, season, and location. Location-related differences are limited to a comparison of results from the five inshore locations versus those

from Georges Bank, the offshore reference location.

SEX-RELATED DIFFERENCES IN BLOOD

CHEMISTRY

Significant differences in blood parameters were observed between males and females within the same season

at Georges Bank (8 instances), New York Bight (5), Mud

Patch (5), and Merrimack River (2), and are shown underlined in Tables 4-10. These differences were observed most

frequently during spring (8), but were also observed during

summer (6), winter (4), and fall (2). Male and female blood

chemistry concentrations differed significantly from one

another for hemoglobin (6), osmolality (4), hematocrit (4),

calcium (3), potassium (2), and MCHC (1).

Mud Patch males had significantly greater hematocrit

during winter, and hematocrit, hemoglobin, and osmolality

during spring, than females. Mud Patch females had significantly greater hemoglobin during summer than males.

Merrimack River females had significantly greater calcium

during spring and summer than males. New York Bight

males had significantly greater hematocrit and osmolality

during winter, hemoglobin and osmolality during spring,

and potassium during fall, than females. Georges Bank males

had significantly greater hemoglobin during winter, hematocrit and hemoglobin during spring, hemoglobin, potassium, and MCHC during summer, and osmolality during fall,

than females; however, females had significantly greater

calcium during summer than males.

SEASONAL DIFFERENCES IN BLOOD CHEMISTRY

Overall, osmolality showed few significant differences

among seasons, although there was a minor trend toward

reduced osmolality during spring, as observed in both males

and females from Georges Bank (Table 4). Fall osmolality in

Mud Patch fish was significantly greater than summer osmolality in males, and spring osmolality in females. Osmolality in New York Bight males was significantly elevated

during winter and spring, and reduced during fall.

Generally, sodium concentrations were significantly

lower during spring, as observed in males from Georges

Bank, Merrimack River, Mud Patch, and New York Bight,

and in females from Georges Bank and Mud Patch (Table 5).

Potassium concentrations were often significantly

higher during spring or summer, and significantly lower

during fall or winter (Table 6). Potassium showed signifi-
Page 3

cantly higher levels during spring in males from Merrimack

River, and in females from Georges Bank and Mud Patch.

Summer levels were significantly higher in fish of both sexes

from Georges Bank and Mud Patch. Potassium was significantly lower during fall than spring and/or summer in males

from Georges Bank, Merrimack River, and Mud Patch, and

in females from Georges Bank. Winter potassium was significantly lower than summer for females from Georges Bank

and Mud Patch.

Calcium concentrations were generally higher during

fall, as observed in fish of both sexes from George Bank and

Mud Patch, and in females from New York Bight (Table 7). A

highly elevated calcium concentration during spring was

documented in females from Merrimack River.

Yellowtail flounder demonstrated a trend toward significantly higher hematocrit during spring, as compared with

fall (Table 8). Hematocrit was significantly greater during

spring than fall in fish of both sexes from Merrimack River,

Mud Patch, and New York Bight, and in males from Georges

Bank. Winter hematocrit concentration was significantly

greater than fall concentration in females from Georges Bank.

Hemoglobin showed a similar pattern to that observed

for hematocrit, but the results were less consistent (Table

9). Hemoglobin tended toward significantly greater concentrations during winter and/or spring than fall. Hemoglobin in fish of both sexes from Georges Bank and Merrimack

River was significantly higher during winter than fall, while

spring levels were significantly higher than fall levels in

males and females from Merrimack River, Mud Patch, and

New York Bight, and in males from Georges Bank.

MCHC was generally higher during winter than spring,

as observed at Georges Bank and Merrimack River for males,

and at Merrimack River and New York Bight for females

(Table 10). Winter also tended to have higher MCHC than

fall, as seen at Georges Bank and Merrimack River for males,

and at Merrimack River and Mud Patch for females.

LOCATION-RELATED DIFFERENCES IN BLOOD

CHEMISTRY AS COMPARED TO GEORGES BANK

Blood parameters in fish from the inshore locations were

compared to such parameters in fish from Georges Bank,

the reference location. During winter, osmolality in female

yellowtail flounder from Merrimack River was significantly

lower. During spring, osmolality in both sexes from New

York Bight and in males from Cape Cod Bay was significantly higher. During summer, osmolality in both sexes

from Merrimack River and in males from Mud Patch was

significantly lower. During fall, osmolality in males from

Merrimack River, Mud Patch, and New York Bight was significantly lower (Table 4).

During winter, Merrimack River, Mud Patch, and New

York Bight sodium concentrations in females were significantly reduced. During spring, sodium in females from

Massachusetts Bay, males from Cape Cod Bay, and both

sexes from New York Bight was significantly elevated. Fall

sodium concentrations were reduced in both sexes from

Merrimack River (Table 5).

Reduced potassium was observed during spring in males

from Cape Cod Bay and in females from Massachusetts

Bay and New York Bight. Merrimack River showed elevated

potassium during spring in males. Significantly reduced

potassium was measured in Merrimack River males during

summer. Females from Merrimack River and Mud Patch

and both sexes from New York Bight had elevated fall potassium (Table 6).

Females from Merrimack River and Massachusetts Bay

had significantly higher calcium during spring. Summer

calcium was reduced in female fish from Mud Patch. Calcium concentrations during fall were significantly lower in

both sexes from Merrimack River and in males only from

Mud Patch (Table 7).

During winter, hematocrit was significantly lower in

males from Cape Cod Bay and in females from Mud Patch.

During spring, hematocrit was significantly higher in both

sexes from Merrimack River, and in females from New York

Bight. During summer, hematocrit was significantly higher

in females from New York Bight (Table 8).

During winter, hemoglobin in males from Cape Cod Bay

and New York Bight, and in both sexes from Mud Patch,

was significantly reduced. Merrimack River females had

greater winter hemoglobin. During spring, hemoglobin was

reduced in female fish from Massachusetts Bay and elevated

in females from Merrimack River. Summer hemoglobin was

reduced in Mud Patch males. Fall hemoglobin in New York

Bight and Mud Patch males was significantly higher (Table

9).

Males from Cape Cod Bay and New York Bight had

significantly lower winter MCHC, while in females from

Merrimack River, MCHC was significantly greater. During

summer, males from Merrimack River and females from New

York Bight had significantly reduced MCHC. Male fish

from Merrimack River, Mud Patch, and New York Bight had

significantly higher MCHC during fall (Table 10).

DISCUSSION

SEASONAL AND SEX-RELATED DIFFERENCES IN

BLOOD CHEMISTRY

Blood chemistry and hematological measurements are

significantly affected by the wide range of natural environmental conditions experienced by fish over the course of a

year (Bridges et al. 1976; Warner and Williams 1977; Lane

1979; Dawson 1990; Folmar 1993; Houston 1997; Luskova

1998; O’Neill et al. 1998; Edsall 1999). Changes in temperature (Powers 1980) and season (Shell 1961) are known to

affect oxygen metabolism and hematology. Variations in

blood constituents may be related to natural physiological

cycles, environmental stimuli, or both (Bridges et al. 1976;

Luskova 1998). Metabolic fluctuations in fish such as

growth, activity, and feeding are strongly influenced by
Page 4

environmental cues (Barnhart 1969; Fletcher 1977). Reproductive cycles, associated with season, can place fish under extremes of metabolism and osmoregulation (Courtois

1976), and may alter the content of fish blood (Nagler et al.

1987; Sandstrom 1989; Bjornsson et al. 1998; Luskova 1998).

Osmolality

Yellowtail flounder experienced only minor seasonal fluctuations. In several cases, osmolality values were reduced

during spring. Windowpane (Scophthalmus aquosus) also

experience significantly lower osmolality during spring than

summer and fall (Dawson 1990). In a laboratory study, however, no significant differences were observed in the serum

osmolality of winter flounder (Pseudopleuronectes

americanus) held at –1° and 15°C (Umminger 1970).

The significantly elevated osmolality observed during

winter and spring in males from New York Bight in our study

has some adaptive significance. Pearcy (1961) suggests

that elevated osmotic pressure in flounder during cooler

weather may protect against freezing in fishes inhabiting

cold shallow waters. Serum osmolality was also highest in

winter flounder during the winter months, just prior to

spawning (Pearcy 1961; Umminger and Mahoney 1972).

Osmolality in mummichog (Fundulus heteroclitus) was

found to increase significantly at colder water temperatures

(Umminger 1969).

Seasonal differences in osmotic pressure may be caused

by osmotic imbalance or other factors (Pearcy 1961). An

increase in serum constituents other than the major ions,

such as a buildup of organic and inorganic materials, can

elevate osmolality during cold weather (Pearcy 1961;

Umminger 1969; Umminger and Mahoney 1972). An increase in serum electrolytes may be a compensatory mechanism used by fish to maintain the total number of osmotically active particles in the plasma (Shell 1961). In several

instances, males showed significantly greater osmolality

than females during winter and/or spring. Perhaps females

are undergoing osmotic changes, specifically hemodilution,

related to preparations for late spring spawning.

In our study, osmolality and sodium were highly positively correlated. This high positive correlation would be

expected, as sodium is an important osmotic constituent.

In our study, both of these parameters had similar patterns

of reductions during spring. Also in our study, dissolved

oxygen and osmolality were highly negatively correlated,

which suggests that the reduced osmolality during spring

may be associated with the elevated dissolved oxygen levels following spring turnover.

Sodium

Marine fish exposed to low seawater temperatures often experience increased sodium (Umminger 1969; Murphy

and Houston 1977; Sandstrom 1989). Increases in freezing

point depression of winter flounder blood serum during the

winter months can be attributed in part to elevated plasma

sodium (Fletcher 1981). Winter flounder sampled in Newfoundland had significantly higher sodium during winter

than summer (Fletcher 1977), while sodium in winter flounder from New England was also higher during late winter

(Pearcy 1961; Fletcher 1977). Winter-collected windowpane

had significantly higher sodium than summer and autumn

fish (Dawson 1990). Interestingly, Umminger and Mahoney

(1972) noted no seasonal change in sodium among winter

flounder collected from New Jersey.

In measurements on freshwater fish, sodium levels in

the Eurasian perch (Perca fluviatilis) reached their maximum during mid-winter (Sandstrom 1989), and in rainbow

trout (Oncorhynchus mykiss) were higher during both fall

and winter than during summer (Houston et al. 1968). In

our study, dissolved oxygen concentrations were correlated

negatively with both sodium and osmolality. This correlation suggests a possible disruption of osmoregulatory function at reduced oxygen levels.

Potassium

The significantly reduced potassium levels during cold

weather, which were observed in our study, have also been

described in winter flounder, and may be related to a decline

in metabolism and feeding at lower temperatures (Umminger

and Mahoney 1972; Bentinck-Smith et al. 1987). Reduced

blood potassium concentrations during winter may also be

attributed to a loss of potassium from the cells of body

tissues in response to the cold (Umminger 1969). Potassium in the windowpane was also found to be higher during

summer than fall and winter (Dawson 1990).

Changes in blood potassium levels have also been observed in freshwater fish. Rainbow trout collected during

fall-winter had reduced levels as compared to those fish

collected during summer (Houston et al. 1968). Elevated

potassium levels were also observed at high water temperatures in smallmouth bass (Micropterus dolomieu) (Shell

1961), rainbow trout (Murphy and Houston 1977), channel

catfish (Ictalurus punctatus) (Ellsaesser and Clem 1987),

Eurasian perch (Sandstrom 1989), and madai (Pagrus major) (Woo 1990).

Increased plasma potassium may result from disruption

of potassium regulatory ability at either the external level

(i.e., between the fish and seawater) or internal level (i.e.,

between the intracellular and extracellular fluid), with a resulting release of potassium into the blood. Serum potassium levels may increase in response to elevated tissue

catabolism, or due to osmotic adjustment when compensating for a decline in other serum components (Shell 1961).

Calcium

Calcium plays an important role in osmoregulation (Shell

1961), and is a critical component in the reproductive pro-
Page 5

cesses of fish. In our study, calcium concentrations were

generally higher during fall and lower during spring. This

trend toward calcium being elevated during fall and depressed during spring may reflect the spring and summer

spawning pattern of yellowtail flounder, which peaks during late May (Bigelow and Schroeder 1953; Royce et al.

1959; Fahay 1983; Collette and Klein-MacPhee 2002; Cadrin

and King 2003). Also in our study, a contrasting pattern

was observed in females from Merrimack River; they showed

significantly elevated calcium during spring which may be

related to anthropogenic, rather than seasonal, influences.

In our study, female fish from Georges Bank and

Merrimack River had significantly elevated spring and/or

summer calcium levels as compared to males. These elevated calcium levels in females are most likely related to

hormonal changes linked to spawning activity. In freshwater fish also, calcium concentrations in females during the

spawning period were significantly higher than in males for

lake trout (Salvelinus namaycush)(Edsall 1999), brook trout

(Salvelinus fontinalis)(Booke 1964), and rock bass

(Ambloplites rupestris)(Bidwell and Heath 1993).

Blood calcium has been shown to follow spawning patterns in numerous fish including brook trout (Booke 1964),

rainbow trout (Nagler et al. 1987), English sole (Parophrys

vetula)(Johnson et al. 1991), striped mullet (Mugil

cephalus), pinfish (Lagodon rhomboides) (Folmar et al.

1992), rock bass (Bidwell and Heath 1993), and Atlantic halibut (Hippoglossus hippoglossus) (Bjornsson et al. 1998).

Blood calcium in rainbow trout rises in connection with

yolk synthesis and reaches maximum levels just prior to

spawning (Hille 1982). High spring calcium levels observed

in windowpane (Dawson 1990) appear to correspond with a

late spring and summer spawning season (Bigelow and

Schroder 1953). Calcium varied irregularly in the Eurasian

perch, with fluctuations increasing sharply before and after

spring spawning (Sandstrom 1989). Variations in blood calcium of fish appear to be tied more closely to reproductive

changes than to seasonality or hematopoiesis (i.e., blood

formation) (Luskova 1998).

Hematocrit, Hemoglobin, and MCHC

Hematocrit and Hemoglobin

Hematocrit provides a measurement of red blood cells

(erythrocytes) in whole blood, while the hemoglobin within

those erythrocytes is the main transport mechanism for oxygen and carbon dioxide in the blood. Alterations in blood

oxygen capacity reflect seasonal adjustment in oxygen

transport (Cameron 1970; Anderson et al. 1985). Elevations

in spring hematocrit and hemoglobin are likely due, in part,

to an increase in oxygen consumption and metabolic rates

corresponding to a rise in water temperatures (Powers 1980;

Dwyer et al. 1983; Zanuy and Carrillo 1985; Martinez et al.

1994). Spring hemoconcentration of the blood may also

contribute to elevated hematological levels (Preston 1960).

In addition to these seasonal rhythms, sex also appears

to play a role in hematocrit and hemoglobin levels. In our

study, males sometimes showed higher hematocrit and hemoglobin levels than females during winter and spring. Lane

(1979) also observed significantly higher hematocrit and

hemoglobin levels in male versus female rainbow trout.

These differences in hematology with regard to males and

females may be related to differential oxygen demand by

sex, which in turn may be related to reproductive activity.

Elevations in hematocrit and hemoglobin of rock bass

seemed to occur in relation to the onset of spawning (Bidwell

and Heath 1993).

The fall reduction in yellowtail flounder hematocrit and

hemoglobin levels observed in our study may reflect a corresponding hemodilution of the blood which results in decreased hematological parameters and/or a reduction in

hemopoetic capacity (Preston 1960). Rhythms in hematocrit and hemoglobin concentration may also result from

changes in plasma volume or erythrocyte volume (Sandstrom

1989), for example, an expansion of plasma volume reduces

the density of circulating red blood cells, thereby decreasing hematocrit (Courtois 1976). Changes in metabolism and

hormonal activity, triggered by cooler water temperatures

and declining photoperiod during fall, may result in anemia

(Lane 1979) and reduced erythropoetic production (Lane

1979; Zanuy and Carrillo 1985). Physiological stresses associated with fasting and spawning can trigger a decline in

fish condition (Bridges et al. 1976; Sano 1960ab; Lane 1979;

Zanuy and Carrillo 1985).

Seasonal hematological patterns vary among species.

In plaice, Pleuronectes platessa, hematocrit was lowest

during winter, increased through the spring into summer,

and declined again into fall. Hemoglobin levels in that species were high at the end of winter, were lowest during

spring, were again high during the summer, and had a further decline during late fall (Preston 1960). In windowpane,

Dawson (1990) found significantly lower winter hematocrit.

Winter flounder from Maine had the lowest levels of hematocrit and hemoglobin during winter and early spring

(Bridges et al. 1976), while winter flounder from New Jersey

had lower levels of hemoglobin during late winter (Umminger

and Mahoney 1972). Tun and Houston (1986) found increased hematocrit and hemoglobin in rainbow trout exposed to summer versus winter conditions. An overall trend

toward increased hemoglobin was observed in pinfish and

striped mullet held at high temperatures (Cameron 1970).

Hematocrit and hemoglobin in striped bass (Morone

saxatilis) were highest during fall and winter and lowest

during summer (Lochmiller et al. 1989). Haider (1969) found

hemoglobin in rainbow trout to be highest during winter

and lowest during fall.

MCHC

Changes in the hemoglobin content of the blood in response to the environment might come about either by a
Page 6

change in the number of erythrocytes or by a change in the

hemoglobin concentration of the individual cells (Anthony

1961). MCHC, the amount of hemoglobin in a given number

of red blood cells, was generally higher during winter than

spring and fall. Since MCHC values are directly related to

erythrocyte maturation, the relatively high proportion of

newly proliferated young erythrocytes during late spring

-- when fish are in a state of rapid growth -- is associated

with relatively low MCHC values (Denton and Yousef 1975;

Hardig and Hoglund 1983). MCHC corresponded with hematocrit and hemoglobin in striped bass, being highest

during fall and winter and lowest during summer (Lochmiller

et al. 1989). MCHC in the largescale blackfish (Girella

punctata), increased during spring and decreased during

fall (Kakuno and Koyama 1994). Dawson (1990) observed

no seasonal or location differences in MCHC among windowpane collected from various locations in Long Island

Sound.

 As hemoglobin is a measure of the amount of oxygen

carried in the blood, the strong positive correlation observed

in our study between dissolved oxygen and two hematological indices, hemoglobin and MCHC, would be expected.

Similarly, Kakuno and Koyama (1994) observed a strong

positive correlation between hematological parameters and

dissolved oxygen in teleost fishes. Also in our study, MCHC

correlated positively with salinity and negatively with sodium concentration. These results suggest that hematological indices may be affected by seasonal changes in hydrographic conditions.

LOCATION-RELATED DIFFERENCES IN BLOOD

CHEMISTRY AS COMPARED TO GEORGES BANK

One of the most important potential uses of blood chemistry data from a toxicological perspective is to assess environmental quality by comparing animals from different locations (i.e., reference versus contaminated locations)

(Folmar 1993). Physiological biomonitoring, using hematological and metabolic indices to assess stress, could provide an alternative to traditional population-based approaches (Lochmiller et al. 1989). A knowledge of normal

physiological values is necessary to evaluate the health of

fish with respect to their physiological responses to a stimulus or stress which affects homeostasis (Luskova 1998). A

variety of environmental pollutants, such as certain chlorinated hydrocarbons and heavy metals, have been shown

to affect osmotic and ionic regulation in fish (Haux 1979;

Heath 1995).

Differences in blood parameters between yellowtail

flounder from inshore locations and those from Georges

Bank, the offshore location, suggest a possible anthropogenic effect at several inshore locations. Blood constituents that are significantly elevated or reduced in inshore

fish as compared to Georges Bank fish may indicate a physiologically stressed condition (Reid et al. 1987). By virtue of

location, the Georges Bank location experiences minimal

input from anthropogenic sources, whereas the inshore locations are known to contain contaminated sediments

(Boehm 1983). In a summary of the NEMP, Reid et al. (1987)

documented elevated trace metals in the sediments from

New York Bight, Mud Patch, and Massachusetts Bay, as

well at the mouths of coastal estuaries. New York Bight had

the highest measurements of polychlorinated biphenyls,

while the incidence of fin rot at that location was found to

be significantly greater than at other Northwest Atlantic

locations (Ziskowski et al. 1987).

Osmolality and Sodium

Significantly lower osmolality levels in Merrimack River,

Mud Patch, and New York Bight male yellowtail flounder

during fall, and significantly lower sodium levels in

Merrimack River males and females during the same season, suggest reduced osmoregulatory capacity, and may

indicate an anthropogenic effect, as chronic low osmolality

levels are thought to result from exposure to contaminants

(Wedemeyer and Yasutake 1977). Dawson (1990) documented significantly reduced osmolality in windowpane from

a polluted harbor in Long Island Sound as compared to fish

from other, less impacted areas. European flounder

(Platichthys flesus) exposed to titanium dioxide industrial

effluent experienced reductions in osmolality and blood

sodium (Larsson et al. 1980). Reduced blood sodium was

documented in rainbow trout exposed to chlorine (Zeitoun

et al. 1977). Leakage of sodium and other ions from extracellular fluids, or decreased uptake of these ions through

the gills, can contribute to impaired osmoregulatory ability

(Pearcy 1961; Larsson et al. 1980).

The significantly elevated spring osmolality and blood

sodium levels observed in New York Bight male and female

yellowtail flounder may indicate a pollutant effect. Windowpane exposed to mercury in the laboratory showed elevated sodium concentrations (Dawson 1990). A marked

increase in blood sodium was observed in seawater-acclimated rainbow trout exposed to bunker C oil, most likely

resulting from direct interference of the oil with the sodium

transport system of the gills (McKeown and March 1978).

Potassium

Significantly elevated potassium levels were observed

during fall in yellowtail flounder males and females from

New York Bight, and in females from Merrimack River and

Mud Patch. These elevated levels may result from impaired

uptake of potassium ions through the gills, disruption of

food absorption in the intestinal mucosa, or defective renal

function and impaired reabsorption of potassium ions in

the renal tubes (Larsson et al. 1981).

Elevated potassium is also known to result from chlorine exposure in rainbow trout (Zeitoun et al. 1977). European flounder exposed to sublethal cadmium concentra-
Page 7

tions showed a dose-dependent reduction in potassium

concentration (Larsson et al. 1981).

Calcium

Calcium was significantly elevated in Massachusetts

Bay and Merrimack River females during spring, while levels were significantly reduced in females from Mud Patch

during summer, and in fish of both sexes from Merrimack

River and males from Mud Patch during fall. These values

differed significantly from Georges Bank, perhaps symptomatic of impaired physiological processes. Larsson et al.

(1981) speculates that a disturbance in calcium metabolism

of fish may be caused by defective calcium absorption or

impaired calcium reabsorption in the renal tubes, or a combination of these effects.

In laboratory exposures, windowpane exposed to mercury (Dawson 1990) and European flounder exposed to cadmium experienced reduced calcium concentration (Larsson

et al. 1981).

Hematocrit, Hemoglobin, and MCHC

With only one exception, yellowtail flounder from Cape

Cod Bay had the lowest levels of hematocrit, hemoglobin,

and MCHC by sex during winter. These levels for Cape Cod

Bay fish were also among the lowest levels over all seasons

and locations in our study. Mud Patch females had the

lowest level of winter hematocrit; they also had the next-tolowest level of winter hemoglobin. Similarly, anemic summer flounder (Paralichthys dentatus), winter flounder, and

windowpane were also collected from Cape Cod Bay and

Mud Patch during NEMP cruises (Reid et al. 1987). Reduced hematocrit and/or hemoglobin can indicate physiological stresses such as anemia, dehydration, and hemodilution resulting from either gill damage (Wedemeyer and

Yasutake 1977) or increased red blood cell breakdown in the

spleen (Larsson et al. 1980). Reduced MCHC suggests

disruption of the hemoglobin-forming process as opposed

to the rate of blood cell production (Heath 1995). Reduced

hematocrit, hemoglobin, and MCHC were documented in

redear sunfish (Lepomis microlophus) collected next to a

selenium discharge site; the selenium appeared to interfere

with normal hemoglobin formation, evidenced by the disproportionate reduction in hemoglobin as compared to red

blood cells (Sorensen and Bauer 1983). European flounder

exposed to cadmium in the laboratory experienced significant reductions in hematocrit and hemoglobin with no associated change in MCHC. In this case, the cadmium-induced anemic response may be due to increased blood

plasma volume, accelerated loss or destruction of erythrocytes, and/or decreased rate of erythrocyte production

(Johansson-Sjobeck and Larsson 1978).

During spring, elevated hematocrit was noted in yellowtail flounder males and females from Merrimack River,

and females from New York Bight; it likely represents a swelling of cells in response either to high blood levels of carbon

dioxide or to low pH rather than an increase in the number

of circulating erythrocytes (Heath 1995), as no significant

difference was noted in MCHC. Hematocrit may increase in

response to stress at a different rate than that of the hemoglobin contained in the erythrocytes (Wells et al. 1986).

During fall, males from Mud Patch and New York Bight

showed elevated hemoglobin, possibly a response to anthropogenic factors. Abnormally elevated hematocrit or

hemoglobin may be related to hemoconcentration, dehydration stress, or polycythemia (Wedemeyer and Yasutake

1977), or to osmoregulatory dysfunction (Heath 1995). Also

during fall, significantly elevated MCHC was measured in

males from Merrimack River, Mud Patch, and New York Bight,

and may indicate a greater amount of hemoglobin per unit

of red blood cells and possibly swollen erythrocytes. Windowpane from a polluted harbor in Long Island Sound had

significantly higher hematocrit and hemoglobin than other

less-impacted areas, suggesting increased hematopoiesis

(Dawson 1990). Larsson et al. (1980) also saw increased

hematocrit and hemoglobin in female European flounder

exposed to titanium dioxide industrial effluent in the field,

and noted that flounder may try to compensate for impaired

oxygen uptake by a release of erythrocytes from the spleen.

Increased hematocrit was observed in rainbow trout stressed

by chlorine exposure (Zeitoun et al. 1977).

CONCLUSIONS

Seasonally-induced variability was observed in yellowtail flounder blood constituent levels. This variability suggests that blood chemistry values are best defined in terms

of a physiological reference range (Luskova 1998).

Seasonal patterns were not always consistent among

the study locations and may reflect natural variability

among locations (Bidwell and Heath 1993). This variability

may result from inherent differences in regional oceanographic conditions, such as temperature and salinity, but

may also be influenced by handling stress, and/or stockrelated variations or a combination of these factors

(McCarthy et al. 1973; Hille 1982).

Our results present some evidence for possible anthropogenic effects on certain blood chemistry parameters of

yellowtail flounder collected from inshore locations. Perhaps the most valuable aspect of this study, though, is that

it presents a benchmark for changes due to environmental

factors or anthropogenic influences over an annual cycle at

key locations in the Northeast U.S. Shelf Ecosystem.
Page 8

ACKNOWLEDGMENTS

The authors thank Anthony Calabrese, Ronald

Goldberg, and Frederick Thurberg for editorial assistance,

Suellen Fromm for providing the NEMP hydrographic data,

Christine Zetlin for designing Figure 1, and Jose Pereira and

Dee Tucker for technical assistance.

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Table 1. General coordinates (latitude and longitude) of stations, and numbers of adult yellowtail flounder collected at those stations, during 1978-85

Coordinates

Location Station No. Latitude Longitude No. of Fish

Georges Bank

17 42° 00'N 67° 00'W 3520 40° 58'N 67° 33'W 122

24 40° 20'N 69° 00'W 1184 40° 48'N 67° 41'W 18

261 40° 48'N 68° 38'W 20264 40° 35'N 69° 31'W 13

Merrimack River 13 42° 48'N 70° 45'W 184

Massachusetts Bay 14 42° 19'N 70° 36'W 34Cape Cod Bay 15 42° 09'N 70° 25'W 34Mud Patch

27 40° 29'N 70° 12'W 2035 40° 41'N 71° 22'W 143

237 40° 43'N 70° 11'W 15250 40° 27'N 70° 14'W 20254 40° 50'N 70° 32'W 20

New York Bight

40 40° 26'N 73° 11'W 4842 40° 25'N 73° 46'W 1047 40° 01'N 73° 25'W 76

235 40° 19'N 72° 07'W 20

Page 11
Table 2. Pearson product moment correlations for Northwest Atlantic hydrographic conditions and blood constituent levels in trawl-collected adult yellowtail flounder during 1978-85. (Sample

sizes ranged from 268 to 830. R-values >0.4, shown in bold, were considered significant.)

Temperature Salinity Dissolved Oxygen Osmolality Sodium Potassium Calcium Hematocrit Hemoglobin MCHC

Temperature -

Salinity 0.11 -Dissolved Oxygen -0.15 0.22 -Osmolality -0.01 -0.12 -0.65 -

Sodium 0.11 -0.38 -0.57 0.56 -

Potassium 0.38 -0.08 -0.02 0.14 0.16 -

Calcium 0.15 0.00 -0.03 0.33 0.27 0.01 -Hematocrit -0.01 0.01 0.08 0.08 0.00 0.04 0.11 -Hemoglobin -0.23 0.33 0.57 -0.12 -0.22 -0.03 0.06 0.74 -

MCHC -0.14 0.52 0.98 -0.36 -0.44 -0.03 -0.08 -0.23 0.53 -

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Table 3. MANCOVA results for blood constituent levels in trawl-collected adult yellowtail flounder from the Northwest Atlantic during 1978-85

Constituent

Variable Osmolality Sodium Potassium Calcium Hematocrit Hemoglobin MCHC

Sex 0.1884 0.1475 0.8539 0.3480 0.2809 0.1525 0.6788Site <0.0001 <0.0001 0.0110 0.0041 <0.0001 <0.0001 0.0012Season 0.8979 0.0002 <0.0001 <0.0001 <0.0001 <0.0001 <0.001Sex × Site 0.0183 0.6918 0.2616 0.0018 0.2501 0.1291 0.6750Sex × Season 0.5923 0.1028 0.1669 0.5396 0.0024 0.0179 0.0522

Sex × Site × Season 0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001 <0.0001Length 0.0331 <0.0001 <0.0001 0.0218 0.0137 0.0063 0.4442

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Table 4. Blood osmolality (ls mean mOsm/kg ± s (N)) in adult yellowtail flounder trawl-collected from six Northwest Atlantic locations during 1978-85. (Station-related

differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read horizontally).Season-related differences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with the sameor no superscript are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station and season areindicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York Bight

Male

Winter 494.16 ± 18.43 (4) 418.49 ± 13.01 (8) 431.70 ± 15.07 (6) 503.39 ± 18.41 (4) 454.29 ± 13.95 (7) 463.40 ± 9.98 (14)a

Spring 440.14 ± 6.97 (28)a 429.47 ± 16.47 (5) 430.09 ± 26.19 (2) 485.76 ± 10.21 (13) 450.00 ± 7.91 (22) 476.44 ± 7.22 (27)aSummer 472.57 ± 10.21 (13)b 426.77 ± 8.93 (17) nd nd 436.58 ± 8.39 (20)a nd

Fall 487.10 ± 9.89 (14)b 412.47 ± 6.54 (32) nd nd 461.67 ± 6.67 (32)b 436.02 ± 10.27 (14)b

Female

Winter 447.68 ± 7.80 (24)a 410.44 ± 13.91 (7) 455.36 (1) 495.49 ± 26.03 (2) 435.45 ± 10.21 (13) 434.33 ± 9.22 (16)

Spring 425.17 ± 6.36 (35)b 436.45 ± 16.51 (5) 454.18 ± 13.93 (7) 488.45 ± 18.57 (4) 428.86 ± 6.66 (32)a 453.83 ± 8.24 (20)Summer 450.51 ± 5.62 (44)a 423.31 ± 10.30 (13) nd nd 440.05 ± 8.67 (18) 448.31 ± 21.45 (3)Fall 436.43 ± 11.27 (11) 415.25 ± 5.23 (53) nd nd 451.65 ± 5.15 (51)b 434.85 ± 9.99 (14)

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Table 5. Blood sodium concentration (ls mean mEq/L ± s (N)) in adult yellowtail flounder trawl-collectedfrom six Northwest Atlantic locations during 1978-85. (Station-related

differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read horizontally).

Season-related differences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with the same

or no superscript are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station and season areindicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York BightMale

Winter 248.84 ± 7.97 (4) 209.58 ± 5.63 (8) 206.71 ± 6.52 (6) 203.85 ± 7.96 (4) 227.16 ± 6.03 (7)a 221.64 ± 4.18 (15)Spring 205.61 ± 2.55 (39)a 201.27 ± 7.12 (5)a 217.97 ± 11.32 (2) 235.02 ± 4.41 (13) 201.26 ± 3.41 (22)b 217.18 ± 3.07 (28)a

Summer 218.72 ± 4.42 (13)b 220.44 ± 3.86 (17)b nd nd 214.28 ± 3.54 (21)a nd

Fall 223.80 ± 4.01 (16)b 200.77 ± 2.79 (33)a nd nd 215.21 ± 2.80 (34)a 229.90 ± 4.94 (11)b

Female

Winter 253.99 ± 3.30 (25)a 209.03 ± 6.02 (7) 231.85 (1) 206.50 ± 9.20 (3) 225.14 ± 4.42 (13)a 217.29 ± 3.99 (16)

Spring 204.15 ± 2.51 (42)b 205.63 ± 7.14 (5) 217.23 ± 5.65 (8) 242.67 ± 8.03 (4) 209.89 ± 2.79 (34)b 215.41 ± 3.57 (20)

Summer 213.15 ± 2.43 (44)c 216.68 ± 4.28 (14)a nd nd 218.68 ± 3.65 (19) 257.52 ± 9.27 (3)

Fall 216.82 ± 4.87 (11)c 203.65 ± 2.30 (50)b nd nd 213.85 ± 2.23 (51)b 219.30 ± 4.48 (13)

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Table 6. Blood potassium concentration (ls mean mEq/L± s (N)) in adult yellowtail flounder trawl-collectedfrom six Northwest Atlantic locations during 1978-85. (Stationrelated differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read

horizontally). Season-related differences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with

the same or no superscript are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station andseason are indicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York BightMale

Winter 4.60 ± 1.09 (4) 3.98 ± 0.77 (8)a 3.78 ± 0.89 (6) 3.56 ± 1.09 (4) 4.74 ± 0.83 (7) 2.90 ± 0.57 (15)a

Spring 4.54 ± 0.34 (39)b 6.59 ± 0.97 (5)b 3.37 ± 1.27 (3) 2.95 ± 0.63 (12) 4.87 ± 0.48 (21)b 4.45 ± 0.44 (26)bSummer 6.98 ± 0.60 (13)a 5.24 ± 0.53 (17) nd nd 6.28 ± 0.48 (21)a nd

Fall 4.30 ± 0.55 (16)b 4.31 ± 0.37 (35)a nd nd 4.93 ± 0.40 (31)b 7.62 ± 0.65 (12)c

Female

Winter 4.22 ± 0.45 (25)a 3.53 ± 0.82 (7) 4.65 (1) 4.74 ± 1.26 (3) 3.77 ± 0.60 (13)a 3.10 ± 0.55 (16)

Spring 5.30 ± 0.34 (42)b 4.16 ± 0.98 (5) 3.35 ± 0.77 (8) 2.45 ± 1.10 (4) 5.62 ± 0.39 (32)b 4.02 ± 0.50 (19)Summer 5.47 ± 0.33 (44)b 4.36 ± 0.59 (14) nd nd 6.40 ± 0.50 (19)b 11.69 ± 1.27 (3)

Fall 3.03 ± 0.67 (11)a 5.02 ± 0.32 (50) nd nd 5.36 ± 0.32 (46)b 5.68 ± 0.64 (12)

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Table 7. Blood calcium concentration (ls mean mEq/L ± s (N)) in adult yellowtail flounder trawl-collected from six Northwest Atlantic locations during 1978-85. (Stationrelated differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read

horizontally). Season-related differences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with

the same or no superscript are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station andseason are indicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York BightMale

Winter 4.19 ± 0.64 (4) 4.51 ± 0.45 (8) 4.53 ± 0.52 (6) 4.60 ± 0.64 (4) 4.52 ± 0.48 (7) 5.31 ± 0.34 (15)

Spring 4.50 ± 0.20 (39)a 4.86 ± 0.57 (5) 5.76 ± 0.91 (2) 3.79 ± 0.37 (12) 4.24 ± 0.27 (22) 5.05 ± 0.25 (28)

Summer 4.34 ± 0.35 (13)a 4.22 ± 0.31(17) nd nd 3.97 ± 0.28 (21)a nd

Fall 6.31 ± 0.34 (14)b 4.24 ± 0.24 (29) nd nd 4.78 ± 0.22 (34)b 5.33 ± 0.38 (12)

Female

Winter 4.64 ± 0.26 (25)a 4.75 ± 0.48 (7)b,c 4.77 (1) 5.08 ± 0.74 (3) 4.25 ± 0.35 (13) 4.84 ± 0.32 (16)

Spring 4.44 ± 0.20 (41)a 7.75 ± 0.52 (6)a 5.67 ± 0.45 (8) 4.66 ± 0.64 (4) 4.23 ± 0.22 (34)a 4.40 ± 0.29 (19)a

Summer 5.27 ± 0.19 (44)b 5.25 ± 0.34 (14)b nd nd 3.97 ± 0.29 (19) a 2.56 ± 0.74 (3)

Fall 5.64 ± 0.39 (11)b 4.28 ± 0.19 (47)c nd nd 4.99 ± 0.18 (51)b 5.71 ± 0.36 (13)b

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Table 8. Hematocrit (ls mean % ± s (N)) in adult yellowtail flounder trawl-collected from six Northwest Atlantic locations during 1978-85. (Station-related differences (i.e.,

between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read horizontally). Season-relateddifferences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with the same or no superscript

are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station and season are indicated by

 underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York Bight

Male

Winter 31.60 ± 2.62 (5)a,b 27.59 ± 2.07 (8)b,c 29.05 ± 2.08 (8) 20.78 ± 2.40 (6) 27.52 ± 2.22 (7)a 30.53 ± 1.45 (17)

Spring 32.05 ± 0.94 (39)a 37.32 ± 2.22 (7)a 17.84 ± 3.41 (3) nd 32.71 ± 1.20 (24)b 30.74 ± 1.09 (30)aSummer 26.91 ± 1.57 (14)b 30.07 ± 1.42 (17)c nd nd 22.49 ± 1.97 (9)a nd

Fall 23.68 ± 1.47 (16)b 23.21 ± 1.02 (33)b nd nd 25.04 ± 1.06 (32)a 26.97 ± 1.58 (15)b

Female

Winter 27.01 ± 1.26 (23)a 26.81 ± 2.39 (6)a 25.62 (1) 22.23 ± 2.93 (4) 21.21 ± 1.62 (13)a 24.58 ± 1.47 (16)b

Spring 25.54 ± 0.89 (46) 34.26 ± 2.22 (7)b 21.91 ± 2.08 (8) nd 26.82 ± 1.00 (36)b 29.20 ± 1.18 (25)aSummer 25.59 ± 0.87 (46) 26.23 ± 1.47 (16)a nd nd 26.07 ± 1.42 (17)b,c 33.76 ± 2.64 (5)aFall 22.57 ± 1.87 (10)b 24.94 ± 0.86 (49)a nd nd 24.00 ± 0.85 (47)a,c 23.56 ± 1.58 (14)b

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Table 9. Hemoglobin concentrations (ls mean g/100 ml ± s (N)) in adult yellowtail flounder trawl-collected from six Northwest Atlantic locations during 1978-85. (Stationrelated differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are indicated by bold values (read

horizontally). Season-related differences for a given station and sex are indicated by the presence or absence of superscripts for the values (read vertically); values with

the same or no superscript are not significantly different; values with different superscripts are significantly different. Sex-related differences for a given station andseason are indicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For statistical significance, P < 0.05.) 

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York Bight

Male

Winter 6.40 ± 0.49 (5)a 6.18 ± 0.38 (8)a 5.87 ± 0.38 (8) 3.29 ± 0.44 (6)a 5.00 ± 0.41 (7)a,c 5.23 ± 0.27 (17)

Spring 5.65 ± 0.17 (40)a 6.21 ± 0.41 (7)a 3.17 ± 0.63 (3) 4.98 ± 0.30 (13)b 5.67 ± 0.22 (25)a 5.48 ± 0.19 (35)a

Summer 5.54 ± 0.31 (12)a 5.02 ± 0.26 (17)b nd nd 4.01 ± 0.24 (21)b nd

Fall 3.70 ± 0.27 (16)b 4.28 ± 0.18 (35)c nd nd 4.37 ± 0.20 (32)c 4.80 ± 0.29 (15)b

Female

Winter 5.13 ± 0.22 (26)a 6.12 ± 0.41 (7)a 6.32 (1) 3.72 ± 0.54 (4) 4.19 ± 0.30 (13) 4.60 ± 0.26 (17)

Spring 4.48 ± 0.16 (47)b 5.45 ± 0.41 (7)a 3.42 ± 0.38 (8) 4.68 ± 0.49 (5) 4.86 ± 0.19 (36)a 4.86 ± 0.22 (25)a

Summer 4.74 ± 0.18 (36) 4.41 ± 0.27 (16)b nd nd 4.75 ± 0.25 (19)a 4.79 ± 0.49 (5)

Fall 4.04 ± 0.35 (10)b 4.31 ± 0.15 (52)b nd nd 4.16 ± 0.15 (51)b 4.08 ± 0.28 (15)b

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Table 10. Mean corpuscular hemoglobin concentrations (ls mean g/100 ml packed red bloodcells ± s (N)) in adult yellowtail flounder trawl-collected from six Northwest Atlantic

locations during 1978-85. (Station-related differences (i.e., between the five inshore stations and the Georges Bank offshore station) for a given season and sex are

indicated by bold values(read horizontally). Season-related differences for a given stationand sex are indicated by the presence or absence of superscripts for the values(read vertically); values with the same or no superscript are not significantly different; values with different superscripts are significantly different. Sex-related

differences for a given station and season are indicated by underlined values (read vertically). For some stations and seasons, no data (“nd”) were available. For

statistical significance, P < 0.05.)

Offshore Station Inshore Stations

Sex Season Georges Bank Merrimack River Massachusetts Bay Cape Cod Bay Mud Patch New York BightMale

Winter 21.63 ± 1.45 (5)a 22.47 ± 1.14 (8)a 20.41 ± 1.15 (8) 16.07 ± 1.33 (6) 18.23 ± 1.22 (7) 17.20 ± 0.80 (17)

Spring 18.14 ± 0.52 (39)b 16.66 ± 1.22 (7)b,c 18.17 ± 1.88 (3) nd 17.34 ± 0.66 (24) 17.61 ± 0.60 (30)

Summer 21.16 ± 0.93 (12)a,c 16.73 ± 0.78 (17)b nd nd 19.72 ± 1.09 (9) nd

Fall 15.39 ± 0.81 (16)d 18.91 ± 0.57 (32)c nd nd 17.85 ± 0.60 (30) 18.12 ± 0.87 (15)

Female

Winter 19.14 ± 0.69 (23) 22.73 ± 1.32 (6)a 24.91 (1) 16.57 ± 1.62 (4) 19.85 ± 0.90 (13)a 19.27 ± 0.81 (16)a

Spring 17.75 ± 0.49 (46) 16.06 ± 1.23 (7)b 15.45 ± 1.15 (8) nd 18.22 ± 0.55 (36) 17.02 ± 0.65 (25)bSummer 18.20 ± 0.54 (36) 17.44 ± 0.81 (16)b nd nd 19.04 ± 0.78 (17) 14.58 ± 1.46 (5)b

Fall 17.73 ± 1.04 (10) 18.35 ± 0.47 (49)b nd nd 17.72 ± 0.47 (47)b 17.63 ± 0.88 (14)

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approval; and 3) the author arranges for the printing and binding

funds to be transferred to the NEFSC's Research Communications Unit account from another federal account. For all

manuscripts submitted by non-NEFSC authors and published

in this series, the NEFSC will disavow all responsibility for the

manuscripts' contents; authors must accept such responsibility.

The ethics of scientific research and scientific publishing

are a serious matter. All manuscripts submitted to this series

are expected to adhere -- at a minimum -- to the ethical guidelines

contained in Chapter 1 ("Ethical Conduct in Authorship and

Publication") of the CBE Style Manual, fifth edition (Chicago,

IL: Council of Biology Editors). Copies of the manual are

available at virtually all scientific libraries.

edition of the United States Government Printing Office Style

Manual. That style manual is silent on many aspects of scientific

manuscripts. NEFSC publication and report series rely more on the

CBE Style Manual, fifth edition.

For in-text citations, use the name-date system. A special

effort should be made to ensure that the list of cited works contains

all necessary bibliographic information. For abbreviating serial

titles in such lists, use the guidance of the International Standards

Organization; such guidance is easily accessed through the various

Cambridge Scientific Abstracts’ serials source lists (see http://

www.public.iastate.edu/~CYBERSTACKS/JAS.htm). Personal communications must include date of contact and full name and mailing

address of source.

For spelling of scientific and common names of fishes, mollusks, and decapod crustaceans from the United States and Canada,

use Special Publications No. 20 (fishes), 26 (mollusks), and 17

(decapod crustaceans) of the American Fisheries Society (Bethesda,

MD). For spelling of scientific and common names of marine

mammals, use Special Publication No. 4 of the Society for Marine

Mammalogy (Lawrence, KS). For spelling in general, use the most

recent edition of Webster’s Third New International Dictionary of

the English Language Unabridged (Springfield, MA: G.&C.

Merriam).

Typing text, tables, and figure captions: Text, tables, and

figure captions should be converted to WordPerfect. In general,

keep text simple (e.g., don't switch fonts and type sizes, don't use

hard returns within paragraphs, don't indent except to begin

paragraphs). Also, don't use an automatic footnoting function; all

notes should be indicated in the text by simple numerical superscripts, and listed together in an "Endnotes" section prior to the

"References Cited" section. Especially, don't use a graphics

function for embedding tables and figures in text.

Tables should be prepared with a table formatting function.

Each figure should be supplied both on paper and on disk, unless

there is no digital file of a given figure. Except under extraordinary

circumstances, color will not be used in illustrations.

Manuscript Preparation

Organization: Manuscripts must have an abstract, table

of contents, and -- if applicable -- lists of tables, figures, and

acronyms. As much as possible, use traditional scientific

manuscript organization for sections: "Introduction," "Study

Area," "Methods & Materials," "Results," "Discussion" and/

or "Conclusions," "Acknowledgments," and "References Cited."

Style: All NEFSC publication and report series are

obligated to conform to the style contained in the most recent

Northeast Fisheries Science Center

Operations, Management & Information Services Staff

Research Communications Unit

Editorial Office

Manuscript Submission

Authors must submit one paper copy of the double-spaced

manuscript, one disk copy, and original figures (if applicable).

NEFSC authors must include a completely signed-off "NEFSC

Manuscript/Abstract/Webpage Review Form." Non-NEFSC authors who are not federal employees will be required to sign a

"Release of Copyright" form.

Send all materials and address all correspondence to: Jon A.

Gibson (Biological Sciences Editor), NMFS Northeast Fisheries

Science Center, 166 Water Street, Woods Hole, MA 02543-1026.
National Marine Fisheries Service

166 Water Street

Woods Hole, MA 02543-1026

Publications and Reports

of the

Northeast Fisheries Science Center

The mission of NOAA's National Marine Fisheries Service (NMFS) is "stewardship of living marine resources for the benefit of the

nation through their science-based conservation and management and promotion of the health of their environment." As the research

arm of the NMFS's Northeast Region, the Northeast Fisheries Science Center (NEFSC) supports the NMFS mission by "planning,

developing, and managing multidisciplinary programs of basic and applied research to: 1) better understand the living marine resources

(including marine mammals) of the Northwest Atlantic, and the environmental quality essential for their existence and continued

productivity; and 2) describe and provide to management, industry, and the public, options for the utilization and conservation of living

marine resources and maintenance of environmental quality which are consistent with national and regional goals and needs, and with

international commitments." Results of NEFSC research are largely reported in primary scientific media (e.g., anonymously-peerreviewed scientific journals). However, to assist itself in providing data, information, and advice to its constituents, the NEFSC

occasionally releases its results in its own media. Currently, there are three such media:

NOAA Technical Memorandum NMFS-NE -- This series is issued irregularly. The series typically includes: data reports of

long-term field or lab studies of important species or habitats; synthesis reports for important species or habitats; annual reports

of overall assessment or monitoring programs; manuals describing program-wide surveying or experimental techniques; literature

surveys of important species or habitat topics; proceedings and collected papers of scientific meetings; and indexed and/or

annotated bibliographies. All issues receive internal scientific review and most issues receive technical and copy editing.

Northeast Fisheries Science Center Reference Document -- This series is issued irregularly. The series typically includes: data

reports on field and lab studies; progress reports on experiments, monitoring, and assessments; background papers for, collected

abstracts of, and/or summary reports of scientific meetings; and simple bibliographies. Issues receive internal scientific review,

but no technical or copy editing.

Resource Survey Report (formerly Fishermen's Report) -- This information reportis a quick-turnaround report on the distribution

and relative abundance of selected living marine resources as derived from each of the NEFSC's periodic research vessel surveys

of the Northeast's continental shelf. There is no scientific review, nor any technical or copy editing, of this report.

OBTAINING A COPY: To obtain a copy of a NOAA Technical Memorandum NMFS-NE or a Northeast Fisheries Science Center

Reference Document, or to subscribe to the Resource Survey Report, either contact the NEFSC Editorial Office (166 Water St.,

Woods Hole, MA 02543-1026; 508-495-2228) or consult the NEFSC webpage on "Reports and Publications" (http://

www.nefsc.noaa.gov/nefsc/publications/).

ANY USE OF TRADE OR BRAND NAMES IN ANY NEFSC PUBLICATION OR REPORT DOES NOT IMPLY

ENDORSEMENT.

Media

 Mail