NOAA Technical Memorandum NMFS-NE-123

Essential Fish Habitat Source Document:

American Plaice, Hippoglossoides

platessoides,

Life History and Habitat Characteristics

U. S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

Northeast Region

Northeast Fisheries Science Center

Woods Hole, Massachusetts

September 1999
Recent Issues

105. Review of American Lobster (Homarus americanus) Habitat Requirements and Responses to Contaminant Exposures.

By Renee Mercaldo-Allen and Catherine A. Kuropat. July 1994. v + 52 p., 29 tables. NTIS Access. No. PB96-115555.

106. Selected Living Resources, Habitat Conditions, and Human Perturbations of the Gulf of Maine: Environmental and

Ecological Considerations for Fishery Management. By Richard W. Langton, John B. Pearce, and Jon A. Gibson, eds.

August 1994. iv + 70 p., 2 figs., 6 tables. NTIS Access. No. PB95-270906.

107. Invertebrate Neoplasia: Initiation and Promotion Mechanisms -- Proceedings of an International Workshop, 23 June

1992, Washington, D.C. By A. Rosenfield, F.G. Kern, and B.J. Keller, comps. & eds. September 1994. v + 31 p., 8 figs.,

3 tables. NTIS Access. No. PB96-164801.

108. Status of Fishery Resources off the Northeastern United States for 1994. By Conservation and Utilization Division,

Northeast Fisheries Science Center. January 1995. iv + 140 p., 71 figs., 75 tables. NTIS Access. No. PB95-263414.

109. Proceedings of the Symposium on the Potential for Development of Aquaculture in Massachusetts: 15-17 February 1995,

Chatham/Edgartown/Dartmouth, Massachusetts. By Carlos A. Castro and Scott J. Soares, comps. & eds. January 1996.

v + 26 p., 1 fig., 2 tables. NTIS Access. No. PB97-103782.

110. Length-Length and Length-Weight Relationships for 13 Shark Species from the Western North Atlantic. By Nancy E.

Kohler, John G. Casey, Patricia A. Turner. May 1996. iv + 22 p., 4 figs., 15 tables. NTIS Access. No. PB97-135032.

111. Review and Evaluation of the 1994 Experimental Fishery in Closed Area II on Georges Bank. By Patricia A. Gerrior,

Fredric M. Serchuk, Kathleen C. Mays, John F. Kenney, and Peter D. Colosi. October 1996. v + 52 p., 24 figs., 20 tables. NTIS

Access. No. PB98-119159.

112. Data Description and Statistical Summary of the 1983-92 Cost-Earnings Data Base for Northeast U.S. Commercial

Fishing Vessels: A Guide to Understanding and Use of the Data Base. By Amy B. Gautam and Andrew W. Kitts. December

1996. v + 21 p., 11 figs., 14 tables. NTIS Access. No. PB97-169320.

113. Individual Vessel Behavior in the Northeast Otter Trawl Fleet during 1982-92. By Barbara Pollard Rountree. August 1997.

v + 50 p., 1 fig., 40 tables. NTIS Access. No. PB99-169997.

114. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments -- 1996. By Gordon T. Waring, Debra L. Palka, Keith

D. Mullin, James H.W. Hain, Larry J. Hansen, and Kathryn D. Bisack. October 1997. viii + 250 p., 42 figs., 47 tables. NTIS

Access. No. PB98-112345.

115. Status of Fishery Resources off the Northeastern United States for 1998. By Stephen H. Clark, ed. September 1998. vi

+ 149 p., 70 figs., 80 tables. NTIS Access. No. PB99-129694.

116. U.S. Atlantic Marine Mammal Stock Assessments -- 1998. By Gordon T. Waring, Debra L. Palka, Phillip J. Clapham, Steven

Swartz, Marjorie C. Rossman, Timothy V.N. Cole, Kathryn D. Bisack, and Larry J. Hansen. February 1999. vii + 182 p., 16

figs., 56 tables. NTIS Access. No. PB99-134140.

117. Review of Distribution of the Long-finned Pilot Whale (Globicephala melas) in the North Atlantic and Mediterranean.

By Alan A. Abend and Tim D. Smith. April 1999. vi + 22 p., 14 figs., 3 tables. NTIS Access. No. PB99-165029.

118. Tautog (Tautoga onitis) Life History and Habitat Requirements. By Frank W. Steimle and Patricia A. Shaheen. May 1999.

vi + 23 p., 1 fig., 1 table. NTIS Access. No. PB99-165011.

119. Data Needs for Economic Analysis of Fishery Management Regulations. By Andrew W. Kitts and Scott R. Steinback.

August 1999. iv + 48 p., 10 figs., 22 tables. NTIS Access. No. PB99-171456.

120. Marine Mammal Research Program of the Northeast Fisheries Science Center during 1990-95. By Janeen M. Quintal and

Tim D. Smith. September 1999. v + 28 p., 4 tables, 4 app. NTIS Access. No. PB2000-100809.
U. S. DEPARTMENT OF COMMERCE

William Daley, Secretary

National Oceanic and Atmospheric Administration

D. James Baker, Administrator

National Marine Fisheries Service

Penelope D. Dalton, Assistant Administrator for Fisheries

Northeast Region

Northeast Fisheries Science Center

Woods Hole, Massachusetts

September 1999

Essential Fish Habitat Source Document:

American Plaice, Hippoglossoides platessoides,

Life History and Habitat Characteristics

Donna L. Johnson, Peter L. Berrien, Wallace W. Morse,

and Joseph J. Vitaliano

National Marine Fisheries Serv., James J. Howard Marine Sciences Lab., 74 Magruder Rd., Highlands, NJ 07732

This series represents a secondary level of scientifiic 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-123
Editorial Notes on Issues 122-152

in the

NOAA Technical Memorandum NMFS-NE Series

Editorial Production

For Issues 122-152, staff of the Northeast Fisheries Science Center's (NEFSC's) Ecosystems Processes Division have

largely assumed the role of staff of the NEFSC's Editorial Office for technical and copy editing, type composition, and

page layout. Other than the four covers (inside and outside, front and back) and first two preliminary pages, all preprinting

editorial production has been performed by, and all credit for such production rightfully belongs to, the authors and

acknowledgees of each issue, as well as those noted below in "Special Acknowledgments."

Special Acknowledgments

David B. Packer, Sara J. Griesbach, and Luca M. Cargnelli coordinated virtually all aspects of the preprinting editorial

production, as well as performed virtually all technical and copy editing, type composition, and page layout, of Issues

122-152. Rande R. Cross, Claire L. Steimle, and Judy D. Berrien conducted the literature searching, citation checking,

and bibliographic styling for Issues 122-152. Joseph J. Vitaliano produced all of the food habits figures in Issues 122-

152.

Internet Availability

Issues 122-152 are being copublished, i.e., both as paper copies and as web postings. All web postings are, or will soon

be, available at: www.nefsc.nmfs.gov/nefsc/habitat/efh. Also, all web postings will be in "PDF" format.

Information Updating

By federal regulation, all information specific to Issues 122-152 must be updated at least every five years. All official

updates will appear in the web postings. Paper copies will be reissued only when and if new information associated with

Issues 122-152 is significant enough to warrant a reprinting of a given issue. All updated and/or reprinted issues will retain

the original issue number, but bear a "Revised (Month Year)" label.

Species Names

The NMFS Northeast Regions policy on the use of species names in all technical communications is generally to follow

the American Fisheries Societys lists of scientific and common names for fishes (i.e., Robins et al. 1991a), mollusks (i.e.,

Turgeon et al. 1998b

), and decapod crustaceans (i.e., Williams et al. 1989c), and to follow the Society for Marine

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

).

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

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.

c

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.

d

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

e

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

Fish. Bull. (U.S.) 96:686-726.
Page iii

FOREWORD

One of the greatest long-term threats to the viability of

commercial and recreational fisheries is the continuing

loss of marine, estuarine, and other aquatic habitats.

Magnuson-Stevens Fishery Conservation and

Management Act (October 11, 1996)

The long-term viability of living marine resources

depends on protection of their habitat.

NMFS Strategic Plan for Fisheries

Research (February 1998)

The Magnuson-Stevens Fishery Conservation and

Management Act (MSFCMA), which was reauthorized

and amended by the Sustainable Fisheries Act (1996),

requires the eight regional fishery management councils to

describe and identify essential fish habitat (EFH) in their

respective regions, to specify actions to conserve and

enhance that EFH, and to minimize the adverse effects of

fishing on EFH. Congress defined EFH as “those waters

and substrate necessary to fish for spawning, breeding,

feeding or growth to maturity.” The MSFCMA requires

NMFS to assist the regional fishery management councils

in the implementation of EFH in their respective fishery

management plans.

NMFS has taken a broad view of habitat as the area

used by fish throughout their life cycle. Fish use habitat

for spawning, feeding, nursery, migration, and shelter, but

most habitats provide only a subset of these functions.

Fish may change habitats with changes in life history

stage, seasonal and geographic distributions, abundance,

and interactions with other species. The type of habitat,

as well as its attributes and functions, are important for

sustaining the production of managed species.

The Northeast Fisheries Science Center compiled the

available information on the distribution, abundance, and

habitat requirements for each of the species managed by

the New England and Mid-Atlantic Fishery Management

Councils. That information is presented in this series of

30 EFH species reports (plus one consolidated methods

report). The EFH species reports comprise a survey of the

important literature as well as original analyses of fisheryJAMES J. HOWARD MARINE SCIENCES LABORATORY

HIGHLANDS, NEW JERSEY

SEPTEMBER 1999

independent data sets from NMFS and several coastal

states. The species reports are also the source for the

current EFH designations by the New England and MidAtlantic Fishery Management Councils, and have

understandably begun to be referred to as the “EFH source

documents.”

NMFS provided guidance to the regional fishery

management councils for identifying and describing EFH

of their managed species. Consistent with this guidance,

the species reports present information on current and

historic stock sizes, geographic range, and the period and

location of major life history stages. The habitats of

managed species are described by the physical, chemical,

and biological components of the ecosystem where the

species occur. Information on the habitat requirements is

provided for each life history stage, and it includes, where

available, habitat and environmental variables that control

or limit distribution, abundance, growth, reproduction,

mortality, and productivity.

Identifying and describing EFH are the first steps in

the process of protecting, conserving, and enhancing

essential habitats of the managed species. Ultimately,

NMFS, the regional fishery management councils, fishing

participants, Federal and state agencies, and other

organizations will have to cooperate to achieve the habitat

goals established by the MSFCMA.

A historical note: the EFH species reports effectively

recommence a series of reports published by the NMFS

Sandy Hook (New Jersey) Laboratory (now formally

known as the James J. Howard Marine Sciences

Laboratory) from 1977 to 1982. These reports, which

were formally labeled as Sandy Hook Laboratory

Technical Series Reports, but informally known as “Sandy

Hook Bluebooks,” summarized biological and fisheries

data for 18 economically important species. The fact that

the bluebooks continue to be used two decades after their

publication persuaded us to make their successors – the 30

EFH source documents – available to the public through

publication in the NOAA Technical Memorandum NMFSNE series.

JEFFREY N. CROSS, CHIEF

ECOSYSTEMS PROCESSES DIVISION

NORTHEAST FISHERIES SCIENCE CENTER
Page v

Contents

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

Life History ...............................................................................................................................................................................................1

Habitat Characteristics ..............................................................................................................................................................................3

Geographical Distribution.........................................................................................................................................................................4

Status of the Stocks ...................................................................................................................................................................................5

Research Needs .........................................................................................................................................................................................6

Acknowledgments.....................................................................................................................................................................................6

References Cited .......................................................................................................................................................................................6

Tables

Table 1. The age and length at maturity of female American plaice, Hippoglossoides platessoides, in the northwest Atlantic............9

Table 2. Summary of life history and habitat parameters for American plaice, Hippoglossoides platessoides...................................10

Table 3. Distribution and relative abundance of American plaice in North Atlantic estuaries and rivers by life history stage ...........12

Figures

Figure 1. The American plaice, Hippoglossoides platessoides (from Goode 1884) .............................................................................14

Figure 2. Distribution and abundance of American plaice from Newfoundland to Cape Hatteras .......................................................15

Figure 3. Abundance of the major prey items in the diet of American plaice based on NEFSC trawl survey data...............................16

Figure 4. Water temperature and depth associated with collections of American plaice eggs during MARMAP surveys ...................17

Figure 5. Water temperature and depth associated with collections of American plaice larvae during MARMAP surveys.................18

Figure 6. Distribution of juvenile and adult American plaice in relation to bottom temperature and depth from NEFSC surveys ......19

Figure 7. Distribution of juveniles and adults in relation to bottom temperature and depth from Massachusetts trawl surveys ..........20

Figure 8. Distribution and abundance of American plaice eggs during MARMAP ichthyoplankton surveys......................................21

Figure 9. Distribution and abundance of American plaice larvae during MARMAP ichthyoplankton surveys ...................................25

Figure 10. Distribution and abundance of juvenile and adult American plaice from NEFSC bottom trawl surveys ..............................27

Figure 11. Distribution and abundance of juvenile and adult American plaice from Massachusetts inshore bottom trawl surveys.......29

Figure 12. Commercial landings and survey indices for American plaice from Gulf of Maine-Georges Bank region, 1963-1996........30

Figure 13. Distribution and abundance of juveniles and adults during low and high abundance periods from NEFSC surveys ...........31
Page 1

INTRODUCTION

The American plaice, Hippoglossoides platessoides,

is an arctic-boreal pleuronectid flatfish that inhabits both

sides of the North Atlantic (Figure 1). In Europe, it is

known as the long rough dab and occurs from Iceland and

Spitzbergen south to the North Sea, the western Baltic,

and as far south as the English Channel. In the western

Atlantic, it is common from the outer coast of Labrador,

south from Hamilton Inlet, Newfoundland, on the Grand

Banks, in the Gulf of St. Lawrence, west and south to

Cape Cod (Figure 2; Bigelow and Schroeder 1953; Smith

et al. 1975). It occurs as far south as Montauk Point, NY.

In Canadian waters, American plaice have been

exploited since the start of the otter trawl fishery in 1947.

It is one of four major species contributing to the

Newfoundland and Labrador fisheries and is the most

abundant flatfish species in the northwest Atlantic

(Bowering and Brodie 1991). In U.S. waters, the fishery

for American plaice started to develop around 1975 in the

Gulf of Maine as the abundance of other commercially

desirable flatfish, such as yellowtail flounder, winter

flounder, and summer flounder, began to decrease

(Sullivan 1981). Prior to 1973, the primary use of

American plaice caught on Georges Bank was for bait

(Lange and Lux 1978).

LIFE HISTORY

EGGS

American plaice spawn buoyant eggs which lack oil

globules. The eggs have a characteristically large,

transparent perivitelline space, which is formed from

water entering between the egg and its membrane

(Bigelow and Schroeder 1953). The average diameter of

an egg is 2.5 mm (range 1.38-3.2 mm). Eggs incubate

from 11 to 14 days at 3.9o

C (Bigelow and Schroeder

1953). During development, the embryo is covered with a

scattered pigment.

In the northwest Atlantic, plaice eggs have been

collected during all months of the year (Berrien and

Sibunka 1999). In the Gulf of Maine and on the Scotian

Shelf, egg abundance peaks in early April and May (Smith

et al. 1975; Neilson et al. 1988).

LARVAE

American plaice larvae hatch at 2.4 mm SL (Fahay

1983) and development of five clusters or groups of

pigment begins at 4-6 mm (Klein-MacPhee, in prep.).

Yolk absorption is complete about 5 days after hatching

when the larva is 6.2-7.5 mm long. Transformation of the

larva and migration of the left eye begins when the larva is

approximately 20 mm. Although the duration of the

transformation process varies with temperature, it is

usually complete when the larva is 30-40 mm (Colton and

Marak 1969).

Sullivan (1981) found that larval plaice were

transported by currents southwest along the coast; some

were retained in the Gulf of Maine while others were

transported to Georges Bank. Changes in circulation

patterns also lead to large numbers of pelagic larvae being

transported off Georges Bank (Colton and Temple 1961;

Sullivan 1981). Larval plaice that drift into the slope

water zone along the southern edge of Georges Bank are

susceptible to transport in a northeasterly direction away

from Georges Bank and the continental shelf. Differences

in temperature between the coastal and slope water zones

could affect the transported larvae by subjecting them to

thermal stress. Plaice larvae were found in relatively

shallow waters on Georges Bank, in Massachusetts Bay,

and along coastal Maine (Smith et al. 1975).

JUVENILES

The body shape continues to change, flattening and

increasing in depth from side to side. As the migration of

the left eye across the top of the head to the right side

reaches completion, descent towards the bottom begins

(Huntsman 1918). Pigment patterns become more

abundant and develop on the right side of the body while

the left side remains unpigmented. Growth during the first

year is greater in warmer, southern climates. Juveniles

can reach 7.6 cm by winter.

ADULTS

The body of the adult plaice is broad with a sharp

noise and wide gaping mouth. Adults obtain average

lengths between 27-66 cm TL. It is the only Gulf of

Maine flounder that is right-handed with a large mouth,

round tail, and straight lateral line with a slight arch over

the pectoral fin (Bigelow and Schroeder 1953).

REPRODUCTION

American plaice is a bottom spawner and the eggs

drift into the upper water column after they are released

(Colton and Temple 1961). Spawning begins north of

Cape Cod in March and continues through the middle of

June (Bigelow and Schroeder 1953; Smith et al. 1975).

Spawning occurs at depths < 90 m and spawning adults

migrate from deeper depths into shoaler grounds before

spawning (Bigelow and Schroeder 1953).

Ichthyoplankton collections made in Cape Cod Bay

revealed that plaice eggs were present from January

through July, and larvae were present from January
Page 2

through August (Scherer 1984). Early stage eggs were

collected on the northern perimeter of the Bay suggesting

that it was a spawning site. The southern distribution of

late-stage eggs suggested displacement by counterclockwise drift patterns in the Bay. It is believed that the

American plaice eggs may have been spawned outside of

Cape Cod Bay and drifted into the Bay by prevailing

currents. The eggs could have drifted as much as 49.0 km

from their original spawning location (Scherer 1984).

Smith et al. (1975) determined from the low larval

occurrence and the prevailing circulation patterns off

southern New England that spawning had occurred along

the southern edge of Georges Bank and that the larvae

were subsequently transported by currents into the Middle

Atlantic Bight.

MATURITY

The median age at maturity for females in the Gulf of

Maine is 3.6 years (O’Brien et al. 1993). Growth rates

are higher and maturity is reached earlier in the southern

areas (Scotian Shelf, Gulf of Maine) than in the north.

The lowest growth rates occurred in St. Mary’s Bay while

the fastest growth rates occurred in the Gulf of Maine

(Table 1). Powles (1965) noted that slower growth rates

were observed in deeper waters. Differences also

occurred between gender and after four years of age,

females grew faster than males and both sexes grew faster

in southern regions.

Water temperatures control spawning in American

plaice resulting in varied times and locations in the

northwest Atlantic (Bowering and Brodie 1991). They

can thrive in temperatures ranging from -0.5 to 13.0o

C

(Bigelow and Schroeder 1953; Bowering and Brodie

1991). Water temperatures from 1.7 to 7.7°C represent

conditions where highest development occurs.

Areas of maximum spawning occur in the western

Gulf of Maine and over southeastern Georges Bank;

optimum spawning temperatures range between 3-6o

C.

These bottom water temperatures exist throughout much

of the spawning period within the 100 m isobath from

Cape Cod to New Jersey (Colton 1972). Outside this

southern boundary, temperatures are too high for survival

rather than too high for reproduction (Colton 1972).

FOOD HABITS

American plaice larvae feed on plankton, diatoms,

and copepods. Prior to settling, juveniles feed on small

crustaceans, polychaetes, and cumaceans (Bigelow and

Schroeder 1953). Feeding competition exists between

young plaice and cod (Powles 1965). Diets of adults are

primarily echinoderms, chiefly sand dollars, sea urchins,

and brittle stars (Huntsman 1918; Pitt 1973; Sullivan

1981). The brittle star, Ophiura sarsi, makes up 65% of

the plaice diet at some locations in the Gulf of Maine

(Klein-MacPhee, in prep.). The diets of plaice collected

during Northeast Fisheries Science Center (NEFSC)

bottom trawl surveys were dominated by echinoderms,

arthropods, annelids, and mollusks (Figure 3) [see Reid et

al. (1999) for a discussion of methods].

Plaice are opportunistic feeders and flexible in their

dietary habits, and will take whatever is most abundant or

accessible (Langton and Bowman 1981; Macdonald and

Green 1986; Langton and Watling 1990; Keats 1991;

Zamarro 1992; Klemetsen 1993; Ntiba and Harding 1993;

Martell and McClelland 1994; Packer et al. 1994;

Berestovskiy 1995). The stomach contents of plaice from

western Nova Scotia, Gulf of Maine, Georges Bank, and

southern New England are generally similar (Powles

1965; Minet 1973; Pitt 1973; Langton and Bowman 1981)

although the specific prey consumed can vary

geographically.

In southern New England, plaice consume large

quantities of amphipods, shrimp (Crangon), polychaetes,

and bivalves (Klein-MacPhee, in prep.). On Georges

Bank, their diet consists primarily of sand dollars, brittle

stars, bivalves, pandalid shrimp, and polychaetes

(Bigelow and Schroeder 1953). In Sheepscot Bay, Maine,

polychaetes, mysids, amphipods, sand shrimp (Crangon

septemspinosa), and Atlantic herring are important prey

(Langton and Watling 1990; Packer and Langton, in

prep.). Offshore in the Gulf of Maine, the brittle star

Ophiura sarsi is one of the dominant epifaunal taxa

(Watling et al. 1988) and is the primary prey of plaice;

crustaceans (euphausiids and pandalid shrimp), bivalve

mollusks (Yoldia spp., Chlamys islandica, Cerastoderma

pinnulatum), and tube-dwelling polychaetes are of

secondary importance (Langton and Bowman 1981;

Bowman and Michaels 1984; Packer et al. 1994). In

Passamaquoddy Bay, Canada, amphipods, mysids,

euphausiids, polychaetes, bivalve mollusks and Atlantic

herring are the major prey of plaice (Tyler 1971, 1972;

Macdonald and Green 1986; Macdonald and Waiwood,

1987).

American plaice can undergo a size-related shift in

their diets. Smaller (< 25-30 cm) individuals feed

predominately on mysids, amphipods, polychaetes, small

brittle stars, and some mollusks. Larger individuals (> 25-

30 cm) feed primarily on fish, brittle stars and other

echinoderms, and bivalve mollusks (Huntsman 1918;

Powles 1965; Pitt 1973; Langton and Bowman 1981;

Bowman and Michaels 1984; Martell and McClelland

1994). Bowman and Michaels (1984) report that

polychaetes are especially important prey of plaice < 20

cm and note that the largest fish feed mostly on

echinoderms. In Sheepscot Bay, Maine, mysids generally

decreased in importance with increasing predator size and

polychaetes appeared to increase (Packer and Langton, in

prep.).

There is little or no feeding during January and

February. This is followed by a rapid increase of feeding
Page 3

in May, which continues through September (Powles

1965). The highest feeding rates occur during the summer

enabling high-energy production for metabolic use and

gonad maturation (MacKinnon 1972).

PREDATION

Plaice ≤ 35 cm are frequently preyed on by cod and

other bottom feeding species (Powles 1965; Bowman and

Michaels 1984). Adults are consumed by Greenland

sharks (Bigelow and Schroeder 1953), goosefish, and

spiny dogfish. Plaice larvae are commonly consumed by

redfish (Klein-MacPhee, in prep.). Along the Scotian

Shelf and in the Gulf of St. Lawrence, grey seals are the

primary predators of plaice (Benoit and Bowen 1990).

MIGRATION

In U.S. and Canadian waters, American plaice is

regarded as a sedentary species migrating only for

spawning and feeding (Pitt 1969; Colton 1972; Bowering

and Brodie 1991).

STOCK STRUCTURE

American plaice is managed as one stock under the

Multispecies Fishery Management Plan of the New

England Fishery Management Council (NEFMC 1993).

The principal gear used to harvest it is the otter trawl;

recreational and foreign catches are insignificant. Since

the mid-1970s, landings from the Gulf of Maine have

exceeded those from Georges Bank. In 1993 the catch in

the Gulf of Maine was more than twice as large as the

catch from Georges Bank (O’Brien 1995).

HABITAT CHARACTERISTICS

The habitat characteristics of American plaice are

summarized by life history stage in Table 2. Data from

the following surveys were used to determine habitat

characteristics: (1) National Marine Fisheries Service

(NMFS), Northeast Fisheries Science Center (NEFSC)

Marine Monitoring Assessment and Prediction

(MARMAP) ichthyoplankton survey, (2) NMFS, NEFSC

bottom trawl survey, (3) Massachusetts Division of

Marine Fisheries (MDMF) bottom trawl survey, and (4)

the NEFSC Food Habits Investigation. A description of

survey methods and materials is found in Reid et al.

(1999).

EGGS

Plaice eggs were collected at temperatures ranging

from about 1-12o

C (Figure 4). During February through

April, most eggs were collected at 2-6o

C. During May to

July the majority of eggs were found at 5-8o

C. From

August to December, eggs were found at higher

temperatures, with most eggs found at 9-11o

C.

Eggs were found over depths ranging from 10-180 m,

with the majority occurring between 50-90 m.

LARVAE

Plaice larvae were captured at temperatures ranging

from 4-14o

C (Figure 5). Larvae were most abundant at 6-

8o

C from March through June and 10-12oC during July

and August.

Larvae were found over depths ranging from 30-210

m, with most occurring at 50-90 m except for August,

where about 45% also occurred at 130 m.

JUVENILES

In the Northeast Fisheries Science Center spring

bottom trawl survey, juvenile American plaice were found

in large numbers at temperatures ranging from 4-6o

C with

an overall range of 2-10o

C (Figure 6). During autumn,

large catches were made in areas with temperatures of 6-

11o

C. They occurred at depths ranging from 15-200 m in

the spring and 50-275 m in the autumn. The majority

occurred at shallower depths of 50-100 m during the

spring to slightly deeper areas of 100-175 m during the

autumn.

In the Massachusetts Division of Marine Fisheries

bottom trawl survey, juvenile plaice were collected at

temperatures ranging from 2-12o

C during the spring and

5-17o

C during the autumn (Figure 7). They were most

abundant at 4-6o

C in the spring and 7-10oC in the autumn.

In the spring, they were found over depths ranging from

10-80 m, with the majority occurring between 45-60 m.

During autumn they were found from 20-80 m with the

majority again occurring between 45-60 m.

ADULTS

The geographic boundaries of American plaice

distribution appear to be defined by warm summer and fall

temperatures. Since the early 1940s, coastal warming and

cooling trends have been observed in waters between

Cape Sable and Long Island (Colton 1972). These trends

are related to changes of subsurface water. Cold years are

defined as years when coastal water from Labrador

displaces slope water. Warm years occur when there is a

low ratio of coastal to central Atlantic water and slope
Page 4

water borders the 200 m isobath.

Huntsman (1918) noted that the maturity of plaice

varied as much as 11 years and depended on the water

temperatures. The highest temperature, 10o

C, for

Passamaquoddy Bay and the Cape Cod region had the

shortest time of development to maturity (3-5 years). The

lowest temperature recorded was 0o

C for Newfoundland

(Bay of Islands) and plaice had the longest development

time (10-13 years) (Huntsman 1918; Bigelow and

Schroeder 1953). On the Scotian Shelf, American plaice

ranged between 0-13o

C with preferences between 1-4oC

(Scott 1982a).

Dow (1977) found that water temperatures influence

the abundance of American plaice in a study of climatic

effects on relative abundance and availability. There were

significant positive correlations between the annual catch

of fish off the Maine coast and mean annual surface

temperatures. These results imply that temperature is a

limiting factor in the abundance of American plaice.

On the Scotian Shelf American plaice range between

27-366 m, with preferences between 55-128 m (Scott

1982a). United States research vessel surveys and

commercial catch statistics confirm similar movement and

depth preferences in the Gulf of Maine (Colton 1972).

Plaice normally occur in waters 25-180 m deep, however

they have been captured at depths > 800 m (Iglesia et al.

1996). They are also found in shoal waters when

temperatures are severely cold (Bigelow and Schroeder

1953). In the Gulf of Maine, plaice occur at depths of 15-

200 m, more frequently at 30-50 m (Klein-MacPhee, in

prep.). With the exception of witch flounder, plaice is

considered the most abundant of all flatfish in the Gulf of

Maine at depths between 54-90 m (Klein-MacPhee, in

prep.). They are also widespread on Georges Bank in 27-

366 m of water.

American plaice occur at mean salinities of 20-22 ppt

in Hamilton Inlet, Labrador (Backus 1957), 30 ppt or

lower in Baltic areas, 32.8 ppt in the Gulf of Maine, and

34 ppt in offshore Atlantic waters (Bigelow and Schroeder

1953).

During a study of fishes of the Scotian Shelf, Scott

(1982a) found American plaice had salinity preferences

between 31-34 ppt; highest abundance occurred at 33 ppt.

Of the 31 species studied by Scott (1982a), American

plaice displayed the widest salinity, depth, and

temperature ranges.

American plaice are frequently found on fine sand or

gravel bottoms (Scott and Scott 1988; Bowering and

Brodie 1991). On the Scotian Shelf, plaice were most

abundant on sand and gravel substrates (Scott 1982b).

They were found in lesser numbers on sand, silt, and clay

and were rare on Scotian Shelf drift (a mixed substrate).

In eastern Newfoundland, plaice were frequently collected

where sandy substrates bordered areas of bedrock. It is

believed that their occurrence near bedrock is because

bedrock is the preferred habitat of an important prey,

green sea urchins, Strongylocentrotus droebachiensis

(Keats 1991). In some areas, their distribution has been

correlated with mud substrates (Walsh 1996; Packer and

Langton, in prep.).

In the Northeast Fisheries Science Center spring

bottom trawl survey, adults appeared to have similar

temperature preferences to juveniles with most found at

temperatures from 4-6o

C with an overall range of 1-12oC

(Figure 6). In autumn, plaice were also mostly found at

temperatures of 4-6o

C. American plaice were collected at

15-300 m deep in the spring and autumn; they were most

abundant between 50-175 m.

In the Massachusetts Division of Marine Fisheries

bottom trawl survey, adults had similar temperature

preferences to juveniles (Figure 7). Adult plaice were

collected at temperatures from 2-9o

C during spring

surveys and 5-14o

C during autumn. Most were found

between 4-6o

C in the spring and 7-10oC in the autumn.

Adults in both spring and autumn were found over depths

ranging from 20-80 m, with most occurring at 45-75 m.

GEOGRAPHICAL DISTRIBUTION

American plaice occur on both sides of the North

Atlantic. On the western side of the Atlantic, it is

common from the outer coast of Labrador, Newfoundland,

the Grand Banks, and the Gulf of St. Lawrence west and

south to Cape Cod; its southern limit is Montauk Point,

NY (Figure 2; Bigelow and Schroeder 1953; Smith et al.

1975). It also occurs in North Atlantic estuaries and rivers

where it ranges from highly abundant to rare (Jury et al.

1994; Table 3).

EGGS

The NEFSC MARMAP ichthyoplankton survey

(1978-1987) captured eggs throughout the year (Figure 8).

During February and March, eggs were collected on

Stellwagen Bank, off Cape Ann, on Jeffreys Ledge, along

coastal Maine, and on Georges Bank. During April and

May, the highest egg concentrations occurred in the mixed

waters and eastern edge of Georges Bank and along the

coastal areas off eastern Massachusetts, the Gulf of

Maine, southwest Nova Scotia, and Browns Bank. From

June through December, eggs were collected almost

exclusively along the coastal areas of in the Gulf of

Maine; some eggs were collected on Georges Bank and

the Scotian Shelf.

LARVAE

Larvae were first captured in the NEFSC MARMAP

ichthyoplankton survey (1977-1987) in small numbers

during March on the southeastern flank of Georges Bank

(Figure 9). By April, numbers increased throughout
Page 5

Georges Bank and larval distributions spread towards the

Great South Channel and onto Nantucket Shoals. Peak

abundance occurred during May from Georges Bank as

far south as Delaware. The highest May abundance

occurred around Cape Cod Bay and along the 60 m

contour on Georges Bank. Larval abundance decreased

dramatically in June and continued to decline in August.

JUVENILES

In the NEFSC bottom trawl survey, juvenile

American plaice occurred from coastal Maine north

towards the Bay of Fundy, west to the Scotian Shelf and

Georges Bank, and south from Cape Cod, the Great South

Channel, and Georges Bank (Figure 10). During winter,

juveniles were caught at scattered locations throughout the

Gulf of Maine. Juveniles were present in only a few

locations along the Great South Channel and the northeast

sector of Georges Bank. In the spring, juveniles were

abundant between Cape Cod and Cape Ann, out to

Stellwagen Bank, and onto Jeffreys Ledge. Juveniles

were captured in lower numbers throughout the Gulf of

Maine. In the summer, juveniles were found in the

inshore and coastal areas of Maine, the Gulf of Maine,

along its western perimeter, and within Cape Cod Bay.

By autumn the center of abundance was located between

Cape Cod and Cape Ann, and along the western part of

the Gulf of Maine; a few juveniles were collected on

Georges Bank and the northeast sector of the Middle

Atlantic Bight. Dense pockets were found within various

basins, the northern end of the Great South Channel, and

along the 100 m contour.

In the Massachusetts Division of Marine Fisheries

bottom trawl survey, juvenile American plaice were

abundant around Cape Ann and in Cape Cod Bay during

spring and autumn (Figure 11).

ADULTS

In the NEFSC bottom trawl survey, adult American

plaice were scattered throughout the Gulf of Maine, the

Great South Channel, Georges Bank and Browns Bank in

the winter (Figure 10). Their distribution was similar in

spring. Larger catches occurred along the Maine coast,

Jeffreys Ledge, and Stellwagen Bank. In the summer and

autumn, adults appeared to leave Georges Bank. Many

were present along the Gulf of Maine, its western

perimeter, and within Cape Cod Bay. Those that

remained on Georges Bank occurred only on the outer

edges of the bank away from the 60 m shoal areas and the

eastern edge of the Middle Atlantic Bight. During

autumn, large catches occurred within various basins, the

northern end of the Great South Channel, and along the

100 m contour.

In the Massachusetts Division of Marine Fisheries

bottom trawl survey, American plaice adults occurred in

significant numbers around Cape Ann during the spring

and autumn (Figure 11).

STATUS OF THE STOCKS

The Gulf of Maine accounts for approximately 72%

of the American plaice landings since 1976. The

remaining U.S. catch originates mainly on Georges Bank;

< 1% of the catch is taken from western Nova Scotia,

southern New England, and the Middle Atlantic Bight

(Sullivan 1981).

From 1963 through 1974, catches from Georges Bank

averaged 2,706 metric tons (mt) or 69% of the U.S. catch

(Figure 12). From 1975 to 1979, landings from Georges

Bank nearly tripled (O’Brien et al. 1992) while catches in

the Gulf of Maine increased from 1,507 to 8,835 mt.

Landings declined in 1986 and continued to drop through

1990 when landings reached an historic low of 637 mt on

Georges Bank. Subsequent increases in landings are

probably due to improved recruitment, an increase in

spawning stock biomass, and an increase in fishing effort

as opposed to an increase in abundance (Sullivan 1981;

O’Brien et al. 1992). The spawning stock biomass

dropped from 41,400 mt in 1980-1982 to 7,700 mt in

1987-1989. By 1991, the presence of the strong 1987

year class raised biomass to 13,400 mt.

Low population indices for the Gulf of Maine and

Georges Bank occurred in 1991-1992, but they increased

dramatically in 1993 due to the 1989 and 1990 year

classes (O’Brien 1995). In 1995, it was estimated that the

American plaice stock would remain overexploited due to

low abundance, increased fishing effort, and increased

discard mortality (O’Brien 1995). In a recent report to

Congress from the Secretary of Commerce (National

Marine Fisheries Service 1997), the American plaice

stock within the jurisdiction of the New England Fisheries

Management Council was classified as “overfished.”

The distribution of American plaice was compared

between years of low abundance (1985-1989) and high

abundance (1976-1981) (Figure 13). When the

population was at low levels, juveniles and adults were

infrequently caught during spring trawl surveys in the Gulf

of Maine and on Georges Bank. Larger catches were only

encountered from Cape Cod to Cape Ann. Strong

recruitment occurred from 1976 to 1981. Large catches of

juveniles and adults occurred in coastal Gulf of Maine and

there were scattered catches along Browns Bank and

Georges Bank. Adults were caught more frequently in the

shoal waters (60 m) of Georges Bank, while the juveniles

were caught more frequently along the northern edge of

Georges Bank.
Page 6

RESEARCH NEEDS

• Determination of how depth, temperature, and bottom

type control the spatial and temporal distribution of

plaice; this is especially important for U.S.

populations where little research has been conducted.

• Confirmation of vertical migration and seasonal

distribution patterns of early life stages.

• Age and growth determination based on otolith

microstructure.

• The strength of habitat dependency and/or interaction

for juveniles and adults.

• Determination of adult migration patterns (i.e.,

tagging studies).

ACKNOWLEDGMENTS

Special acknowledgment goes to reviewers from the

Woods Hole Laboratory, Michael Pentony, members of

the New England Fishery Management Council, and Dr.

Jeffrey Cross for critical reviews and comments. We also

thank librarians Judy Berrien, Rande Ramsey-Cross, and

Claire Steimle for invaluable assistance with literature

searches and style suggestions.

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Page 9

Table 1. The age (A) and length (L) at which 50% of the female American plaice, Hippoglossoides platessoides, are

mature in the northwest Atlantic.

Area A50

(yrs)

L50

(cm)

Year Source

Labrador 8.11 45.84 1978-1988 Bowering and Brodie (1991)

Northern Grand Bank 13.98 42.14 1961-1965 Pitt (1975)

Northern Grand Bank 10.57 40.36 1969-1972 Pitt (1975)

St. Mary’s Bay, Newfoundland 15.20 54.00 1964 Pitt (1966)

Flemish Cap 7.80 40.00 1964 Pitt (1966)

Southeastern Grand Bank 8.79 41.45 1971 Pitt (1975)

St. Pierre Bank 9.48 48.26 1978-1988 Bowering and Brodie (1991)

Scotian Shelf 6.00 31.00 1970-1974 Beacham (1983)

Scotian Shelf 4.70 30.80 1975-1979 Beacham (1983)

Nova Scotia to Cape Hatteras - - 33.60 1979 Morse (1979)

Atl. Coast of N. Am. (77’ - 42’) 8.00 30.00 1991 Miller et al. (1991)

Gulf of Maine 3.80 29.70 1980 Sullivan (1981)

Gulf of Maine 3.60 26.80 1986-1990 O’Brien et al. (1993)
Page 10

Table 2. Summary of life history and habitat characteristics for American plaice, Hippoglossoides platessoides. (NTS =

NMFS Trawl Survey; MITS = Massachusetts Inshore Trawl Survey).

Life Stage Size Range Time of Year

Distribution

Habitat/Location Substrate Temperature

Spawning

Adults 1

March - mid

June, (peak

spawning AprilMay)

American plaice in general

occur along the continental shelf

from southern Labrador to

Montauk Pt. NY. Within

Massachusetts Bay, coastal Gulf

of Maine, and shelf.

March to June 2.7-4.4o

C

Eggs 2

1.5 to 3.0 mm Gulf of Maine:

Jan - Dec

Georges Bank:

Jan - June, Dec.

Pelagic, within the 100 m

contour, along the coast of

Maine, Massachusetts, inshore

and shoal waters of Georges

Bank.

Nursery area = shelf.

Range 1-12o

C

(most 4-8o

C)

Larvae 3

4 to 6 mm at

hatching;

5.1 to 16.4 mm

March - August

(peak = May)

Pelagic, within the 100 m

contour, along the coast of

Maine, Massachusetts, inshore

and shoal waters of Georges

Bank.

Nursery area = shelf.

Range 4-14o

C

(most 5-10o

C)

Juveniles 4

18 to 34 mm at

metamorphosis; 3

cm to < 27cm

(Trawl Surveys)

January –

December

Latitude range (77°, 42°) Strong

concentrations inside and

around the 100m isobath in

western Gulf of Maine during

the spring and autumn surveys.

Scattered abundance in deeper

waters of western and central

Gulf of Maine and the northern

sector of Georges Bank.

Fine sand

and gravel.

NTS Spring 2-10o

C

(most 4-6o

C);

Autumn 4-15o

C (most 6-

11o

C);

MITS Spring 2-12o

C

(most 4-6o

C);

Autumn 5-17o

C (most 7-

10o

C)

Adults 5

≥ 27 cm to 66 cm

(Trawl Surveys);

max size = 81 cm

January -

December

Both sides of the North Atlantic,

latitude range (77°, 42°) boreal.

Fine sand

and gravel.

NTS Spring 1-12o

C

(most 4 to 6o

C);

Autumn 3-11o

C (most 4-

6o

C);

MITS Spring 2-9o

C

(most 4-6o

C);

Autumn 5-14o

C (most 7-

10o

C).

1.7-7.7o

C highest

development;

-1.5o

C lower

temperature limit; 10-

13o

C upper temperature

limit

1 Bigelow and Schroeder 1953, Sullivan 1981, Miller et al. 1991 2 Sullivan 1981, Fahay 1983, Miller et al. 1991 3 Smith et al. 1975, Sullivan 1981 4 Sullivan 1981, Miller et al. 1991, Wigley and Gabriel 1991 5 Miller et al. 1991
Page 11

Table 2. cont’d.

Life Stage Salinity Bottom Depth Estuarine Use Notes

Spawning

Adults 1

32.8 ppt MarchApril, Gulf of

Maine

< 90 m Inshore and shoal

areas, largely an

oceanic nursery

(see Table 3)

Spawning adults migrate from

greater depths into shoaler

grounds before spawning.

Eggs 2

32.8 ppt MarchApril, Gulf of

Maine

Pelagic 10-325 m

(most 30-90 m)

Inshore and shoal

areas, largely an

oceanic nursery

(see Table 3)

Spherical with smooth shell. Only

Pleuronectid known to have a very

wide perivitelline space, no oil

globule. 11-14 day incubation

duration.

Larvae 3

32.8 ppt MarchApril, Gulf of

Maine

30-210 m

(most 50-90 m)

Inshore and shoal

areas, largely an

oceanic nursery

(see Table 3)

Transformation occurs between

18-34 mm (usually > 25 mm SL).

Juveniles 4

32.8 ppt MarchApril Gulf of

Maine

Pelagic-shallow

shelf (36-713 m);

NTS Spring 15-200

m (most 50-100 m);

Autumn 50-275 m

(most 100-170 m);

MITS Spring 10-80

m (most 45-60 m);

Autumn 20-80 m

(most 45-60 m)

Inshore and shoal

areas, largely an

oceanic nursery

(see Table 3)

Larval - juvenile migration =

pelagic to shallow shelf.

Adults 5

32.8 ppt MarchApril Gulf of

Maine; 30 ppt

Baltic, 34 ppt open

Atlantic, 20-22 ppt

Hamilton Inlet,

Labrador

NTS Spring 15-275

m (most 50-175 m);

Autumn 25-300 m

(most 50-175 m);

MITS Spring 5-80 m

(most 45-75 m);

Autumn 20-80 m

(most 45-55, 70 m)

Inshore and shoal

areas, largely an

oceanic nursery

(see Table 3)

1 Bigelow and Schroeder 1953, Sullivan 1981, Miller et al. 1991 2 Sullivan 1981, Fahay 1983, Miller et al. 1991 3 Smith et al. 1975, Sullivan 1981 4 Sullivan 1981, Miller et al. 1991, Wigley and Gabriel 1991 5 Miller et al. 1991
Page 12

Table 3. Distribution and relative abundance of American plaice in North Atlantic estuaries and rivers by life history

stage (from Jury et al. 1994). (*** = Highly Certain; ** = Moderately Certain; * = Reasonable Inference).

Distribution and Relative Abundance

Estuaries and Rivers Life Stage Mixing Seawater

Months of

Occurrence

Data

Reliability

Passamaquoddy Bay Adults (A) Common March - Nov **

 Spawning adults (S) Common March - May **

 Juveniles (J) Common Common March - Nov *

 Larvae (L) Common April - June **

 Eggs (E) Common March - May **

Englishman / Machias Bay A Common March - Nov *

 S Common March - May *

 J Common Common March - Nov *

 L Common April - June *

 E Common March - May *

Narraguagus Bay A Common March - Nov *

 S Common March - May *

 J Common Common March - Nov *

 L Common April - June *

 E Common March - May *

Blue Hill Bay A Common March - Nov *

 S Common March - May *

 J Common Common March - Nov *

 L Common April - June *

 E Common March - May *

Penobscot Bay A Common March - Nov **

 S Common March - May **

 J Common Common March - Nov **

 L Common April - June **

 E Common March - May **

Muscongus Bay A Abundant March - Nov **

 S Common March - May *

 J Common Highly Abundant March - Nov *

 L Rare Common April - June *

 E Common March - May *

Damariscotta River A Abundant March - Nov **

 S Common March - May **

 J Common Highly Abundant March - Nov *

 L Rare Common April - June *

 E Common March - May **

Sheepscot River A Abundant March - Nov ***

 S Common March - May ***

 J Common Highly Abundant March - Nov ***

 L Rare Common April - June ***

 E Common March - May **

Kennebec / Androscoggin Rivers A Abundant March - Nov **

 S Common March - May *

 J Common Highly Abundant March - Nov *

 L Rare Common April - June *

 E Common March - May *

Casco Bay A Abundant March - Nov *

 S Common March - May *

 J Common Highly Abundant March - Nov *

 L Rare Common April - June *

 E Common March - May *
Page 13

Table 3. cont’d.

Distribution and Relative Abundance

Estuaries and Rivers Life Stage Mixing Seawater

Months of

Occurrence

Data

Reliability

Saco Bay A Abundant March. - Nov. *

 S Common March - May *

 J Common Highly Abundant March. - Nov. *

 L Rare Common April - June *

 E Common March - May *

Wells Harbor A *

 S **

 J Rare June - Oct. *

 L Rare April - June *

 E Rare March - May *

Great Bay A Rare March - Nov. *

 S **

 J Rare March - Nov. *

 L Rare April - July *

 E Rare March - June *

Merrimack River A *

 S **

 J Rare March - Sept. *

 L Rare April - July *

 E Rare March - June *

Massachusetts Bay A Highly Abundant Jan. - Dec. ***

 S Highly Abundant Feb. - June **

 J Highly Abundant Jan. - Dec. ***

 L Abundant March - July *

 E Abundant Feb. - June *

Boston Harbor A Abundant Jan. - Dec. **

 S Common Feb. - June *

 J Abundant Jan. - Dec. *

 L Rare Common March - July *

 E Rare Common Feb. - June *

Cape Cod Bay A Abundant Jan. - Dec. **

 S Highly Abundant Feb. - May **

 J Highly Abundant Jan. - Dec. **

 L Rare Highly Abundant March - July **

 E Rare Highly Abundant Feb. - July **
Page 14

Figure 1. The American plaice, Hippoglossoides platessoides (Fabricius 1780) (from Goode 1884).
Page 15

Figure 2. Distribution and abundance of American plaice from Newfoundland to Cape Hatteras based on research trawl

surveys conducted by Canada (DFO) and the United States (NMFS) from 1975-1994 (http://www-orca.nos.noaa.gov/

projects/ecnasap/ecnasap_table1.html).
Page 16

Figure 3. Abundance (percent occurrence) of the major prey items in the diet of American plaice based on NEFSC trawl

survey data on food habitats during 1973-1980 and 1981-1990. Methods for sampling, processing, and analysis of

samples differed between the time periods [see Reid et al. (1999) for details]. The category “animal remains” refers to

unidentifiable animal matter.

Echinodermata 25.6% Annelida 20.5%

Arthropoda 17.7%

Animal Remains 12.3% Mollusca 7.2%

Aschelminths 6.3%

Platyhelminthes 5.1%

Miscellaneous 3.8%

Other Prey 1.5%

Echinodermata 54.7%

Animal Remains 13.7%

Arthropoda 11.6%

Mollusca 7.4%

Annelida 6.3%

Fish 5.3%

Cnidaria 1.1%

a) 1973-1980

n = 764

b) 1981-1990

n = 88
Page 17

Figure 4. Mean water column temperature (to a maximum of 200 m) and bottom depth associated with collections of

American plaice eggs during MARMAP ichthyoplankton surveys, 1978-1987. Open bars represent the proportion of all

stations which were surveyed, while solid bars represent the proportion of the sum of all standardized catches

(number/10 m2

).

January

0

10

20

30

90

100

Stations

Egg Catch

April

0

10

20

30

40

May

0

10

20

40

50

June

Percent

0

10

20

30

40

50

July

0

10

20

30

40

50

August

0

20

40

60

October

0

10

90

100

American Plaice Eggs

September

0

10

20

30

40

February

0

10

20

30

40

50

March

0

20

40

60

November

0

10

20

70

80

December

Water Temperature (0 to 200m, C)

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

0

10

20

30

90

100

January

0

10

20

30

40

50

Stations

Egg Catch

April

0

10

20

30

October

0

10

20

80

American Plaice Eggs

September

0

10

20

30

May

0

10

20

30

40

50

June

Percent

0

10

20

30

40

50

July

0

10

20

30

40

August

0

20

40

60

December

Bottom Depth (m), Interval Midpoint

10

30

50

70

90

110

130

150

170

190

210

230

250

270

290

325

375

450

750

1250

1750

>2000

0

10

20

80

100

November

0

10

20

50

60

March

0

10

20

30

40

50

February

0

10

20

30

40

50
Page 18

Figure 5. Mean water column temperature (to a maximum of 200 m) and bottom depth associated with collections of

American plaice larvae during MARMAP ichthyoplankton surveys, 1977-1987. Open bars represent the proportion of

all stations which were surveyed, while solid bars represent the proportion of the sum of all standardized catches

(number/10 m2

).

April

0

10

20

30

60

70

80

May

0

10

20

30

40

June

Percent

0

10

20

30

July

0

10

20

30

August

Water-Column Temperature (0-200m, C)

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28

0

5

10

35

40

45

American Plaice Larvae

March

0

10

20

30

40

50

Stations

Larva Catch

April

0

10

20

30

40

50

American Plaice Larvae

May

0

10

20

30

40

50

June

Percent

0

10

20

30

July

0

10

20

30

40

August

Bottom Depth (m), Interval Midpoint

10

30

50

70

90

110

130

150

170

190

210

230

250

270

290

325

375

450

750

1250

1750

>2000

0

10

20

30

40

50

March

0

10

20

30

40

50

Stations

Larva Catch
Page 19

Figure 6. Distribution of juvenile and adult American plaice in relation to bottom temperature and depth based on spring

(1968-1997) and autumn (1963-1996) NEFSC bottom trawl surveys. Open bars represent the proportion of all stations

surveyed, while solid bars represent the proportion of the sum of all standardized catches (number/10 m2

).

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

0

10

20

30

40

50

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

0

4

8

12

16

20

0

10

20

30

40

0

10

20

30

0

4

8

12

16

20

0

5

10

15

20

25

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

0

10

20

30

40

Juveniles Adults

Stations

Catches

Spring Spring

Spring Spring

Autumn Autumn

Autumn Autumn

Bottom Depth (m) Bottom Depth (m)

Bottom Depth (m) Bottom Depth (m)

Bottom Temperature (°C) Bottom Temperature (°C)

Bottom Temperature (°C) Bottom Temperature (°C)

NMFS Bottom Trawl Surveys

American Plaice
Page 20

Figure 7. Distribution of juvenile and adult American plaice in relation to bottom temperature and depth based on spring

and autumn Massachusetts inshore bottom trawl surveys, 1978-1996. Open bars represent the proportion of all stations

surveyed, while solid bars represent the proportion of the sum of all standardized catches (number/10 m2

).

1 3 5 7 9 11 13 15 17 19 21 23 0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21 23 0

10

20

30

0

5

10

15

20

25

0

5

10

15

20

25

0

5

10

15

20

25

0

5

10

15

20

25

1 3 5 7 9 11 13 15 17 19 21 23 0

10

20

30

40

1 3 5 7 9 11 13 15 17 19 21 23 0

10

20

30

40

Juveniles Adults

Stations

Catches

Spring Spring

Spring Spring

Autumn Autumn

Autumn Autumn

Bottom Depth (m) Bottom Depth (m)

Bottom Depth (m) Bottom Depth (m)

Bottom Temperature (C) Bottom Temperature (C)

Bottom Temperature (C) Bottom Temperature (C)

Mass. Inshore Trawl Surveys

American Plaice
Page 21

Figure 8. Distribution and abundance of American plaice eggs during MARMAP ichthyoplankton surveys, January to

December, 1978-1987.

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

January to December; 1978 to 1987

Number of Tows = 9478; with Eggs = 416

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

Eggs / 10m2

1 to <10

10 to <100

100 to <1000

1000 to 1703

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

January; 1978 to 1987

Number of Tows = 433; with Eggs = 2

None

1 to 6

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

February; 1978 to 1987

Number of Tows = 459; with Eggs = 31

None

1 to <10

10 to <100

100 to 137

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

March; 1978 to 1987

Number of Tows = 853; with Eggs = 39

None

1 to <10

10 to <100

100 to 254

Eggs / 10m2
Page 22

Figure 8. cont’d.

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

April; 1978 to 1987

Number of Tows = 1020; with Eggs = 187

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to 1703

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

May; 1978 to 1987

Number of Tows = 1085; with Eggs = 77

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to 1074

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

June; 1978 to 1987

Number of Tows = 709; with Eggs = 52

None

1 to <10

10 to <100

100 to 539

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

July; 1978 to 1987

Number of Tows = 781; with Eggs = 8

None

1 to <10

10 to <100

100 to 238

Eggs / 10m2
Page 23

Figure 8. cont’d.

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

August; 1978 to 1987

Number of Tows = 863; with Eggs = 11

None

1 to <10

10 to <100

100 to 116

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

September; 1978 to 1987

Number of Tows = 747; with Eggs = 3

None

1 to 6

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

October; 1978 to 1987

Number of Tows = 1044; with Eggs = 2

None

1 to <10

10 to 42

Eggs / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

November; 1978 to 1987

Number of Tows = 915; with Eggs = 3

None

1 to 10

Eggs / 10m2
Page 24

Figure 8. cont’d.

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

American Plaice

Eggs

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

December; 1978 to 1987

Number of Tows = 569; with Eggs = 1

None

1 to 7

Eggs / 10m2
Page 25

Figure 9. Distribution and abundance of American plaice larvae during MARMAP ichthyoplankton surveys, March to

August, 1977-1987.

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

MARMAP Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

March to August (1977 to 1987)

American Plaice

Number of Tows = 6763, with larvae = 210

1 to < 10

10 to < 100

100 to 509

Number of Larvae / 10m2

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

March (1977 to 1987)

Number of Tows = 1031, with larvae = 6

Number of Larvae / 10m2

None

1 to < 10

10 to 60

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

April (1977 to 1987)

Number of Tows = 1281, with larvae = 50

Number of Larvae / 10m2

None

1 to < 10

10 to < 100

100 to 364

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

May (1977 to 1987)

Number of Tows = 1472, with larvae = 96

Number of Larvae / 10m2

None

1 to < 10

10 to < 100

100 to 509
Page 26

Figure 9. cont’d.

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

June (1977 to 1987)

Number of Tows = 893, with larvae = 40

Number of Larvae / 10m2

None

1 to < 10

10 to 72

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

July (1977 to 1987)

Number of Tows = 938, with larvae = 13

Number of Larvae / 10m2

None

1 to < 10

10 to 27

76 75 74 73 72 71 70 69 68 67 66 65

35

36

37

38

39

40

41

42

43

44

45

August (1977 to 1987)

Number of Tows = 1148, with larvae = 5

Number of Larvae / 10m2

None

1 to < 10

10 to 46
Page 27

Figure 10. Distribution and abundance of juvenile and adult American plaice from winter (1964-1997), spring (1968-

1997), summer (1963-1995), and autumn (1963-1996) NEFSC bottom trawl surveys. Densities are represented by dot

size in spring and autumn plots, while only presence and absence are represented in winter and summer plots [see Reid et

al. (1999) for details].

NMFS Trawl Surveys

Winter 1964 - 97

Juveniles (<27cm)

 = Total Tows

 = Positive Tow

American Plaice

NMFS Trawl Surveys

Summer 1963 - 95

Juveniles (<27cm)

= Absent

 = Present

American Plaice

Number/Tow

 1 to 25

 25 to 100

 100 to 200

 200 to 400

 400 to 615

NMFS Trawl Surveys

Spring 1968 - 97

Juveniles (<27cm)

American Plaice

Number/Tow

 1 to 25

 25 to 100

 100 to 200

 200 to 400

 400 to 657

NMFS Trawl Surveys

Autumn 1963 - 96

Juveniles (<27cm)

American Plaice
Page 28

Figure 10. cont’d.

NMFS Trawl Surveys

Winter 1964 - 97

Adults (>=27cm)

 = Total Tows

 = Positive Tow

American Plaice

Number/Tow

 1 to 25

 25 to 50

 50 to 100

 100 to 150

 150 to 179

NMFS Trawl Surveys

Spring 1968 - 97

Adults (>=27cm)

American Plaice

NMFS Trawl Surveys

Summer 1963 - 95

Adults (>=27cm)

= Absent

 = Present

American Plaice

Number/Tow

 1 to 25

 25 to 50

 50 to 100

 100 to 150

 150 to 165

NMFS Trawl Surveys

Autumn 1963 - 96

Adults (>=27cm)

American Plaice
Page 29

Figure 11. Distribution and abundance of juvenile and adult American plaice from the Massachusetts inshore bottom

trawl surveys, 1978-1996.

American Plaice

Mass. Inshore Trawl Survey

 Spring 1978 - 1996

 Juveniles (<27cm)

Number/Tow

 1 to 100

 100 to 250

 250 to 750

 750 to 1000

 1000 to 1788

American Plaice

Mass. Inshore Trawl Survey

 Autumn 1978 - 1996

 Juveniles (<27cm)

Number/Tow

 1 to 100

 100 to 250

 250 to 500

 500 to 1000

 1000 to 1288

American Plaice

Mass. Inshore Trawl Survey

 Spring 1978 - 1996

 Adults (>=27cm)

Number/Tow

 1 to 50

 50 to 100

 100 to 200

 200 to 300

 300 to 317

American Plaice

Mass. Inshore Trawl Survey

 Autumn 1978 - 1996

 Adults (>=27cm)

Number/Tow

 1 to 50

 50 to 100

 100 to 200

 200 to 300

 300 to 432
Page 30

Figure 12. Commercial landings and survey indices for American plaice from the Gulf of Maine-Georges Bank region,

1963-1996.

Gulf of Maine - Georges Bank

Year

1960 1965 1970 1975 1980 1985 1990 1995 2000

Landings (mt x 1000)

0

2

4

6

8

10

12

14

16

Stratified mean catch/tow (kg)

0

1

2

3

4

5

6

7

Commercial landings (mt)

Survey index (kg)

Smoothed survey index (kg)
Page 31

Figure 13. Distribution and abundance of juvenile and adult American plaice during a period of low abundance (1985-

1989) and a period of high abundance (1976-1981), from spring NEFSC bottom trawl surveys.

Number/Tow

 1 to 25

 25 to 50

 50 to 100

 100 to 200

 200 to 481

NMFS Trawl Surveys

Spring 1985 - 89

Juveniles (<27cm)

Low Abundance

American Plaice

Number/Tow

 1 to 25

 25 to 50

 50 to 75

 75 to 100

 100 to 148

NMFS Trawl Surveys

Spring 1985 - 89

Adults (>=27cm)

Low Abundance

American Plaice

Number/Tow

 1 to 25

 25 to 50

 50 to 100

 100 to 200

 200 to 481

NMFS Trawl Surveys

Spring 1976 - 81

Juveniles (<27cm)

High Abundance

American Plaice

Number/Tow

 1 to 25

 25 to 50

 50 to 75

 75 to 100

 100 to 148

NMFS Trawl Surveys

Spring 1976 - 81

Adults (>=27cm)

High Abundance

American Plaice

NORTHEAST FISHERIES SCIENCE CENTER

Dr. Michael P. Sissenwine, Science & Research Director

CAPT John T. Moakley, Operations, Management & Information Services Staff Chief

Teri L. Frady, Research Communications Unit Chief

Jon A. Gibson, Biological Sciences Editor & Laura S. Garner, Editorial Assistant

Publishing in NOAA Technical Memorandum NMFS-NE

Manuscript Qualification

This series represents a secondary level of scientific publishing in the National Marine Fisheries Service (NMFS). For

all issues, the series employs thorough internal scientific review,

but not necessarily external scientific review. For most issues,

the series employs rigorous technical and copy editing. Manuscripts that may warrant a primary level of scientific publishing

should be initially submitted to one of NMFSs primary series

(i.e., Fishery Bulletin, NOAA Technical Report NMFS, or Marine Fisheries Review).

Identical, or fundamentally identical, manuscripts should

not be concurrently submitted to this and any other publication

series. Manuscripts which have been rejected by any primary

series strictly because of geographic or temporal limitations may

be submitted to this series.

Manuscripts by Northeast Fisheries Science Center

(NEFSC) authors will be published in this series upon approval

by the NEFSC's Deputy Science & Research Director. Manuscripts by non-NEFSC authors may be published in this series if:

1) the manuscript serves the NEFSCs mission; 2) the manuscript meets the Deputy Science & Research Directors approval; and 3) the author arranges for the printing and binding

funds to be transferred to the NEFSCs 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.

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 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 most recent edition of the

Serial Sources for the BIOSIS Previews Database (Philadelphia,

PA: Biosciences Information Service). 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 Websters Third New

International Dictionary of the English Language Unabridged

(Springfield, MA: G.&C. Merriam).

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

tables and figure captions, must be converted to, or able to be

coverted to, WordPerfect. In general, keep text simple (e.g.,

dont switch fonts, dont use hard returns within paragraphs,

dont indent except to begin paragraphs). Especially, dont use

WordPerfect graphics for embedding tables and figures in text.

If the automatic footnoting function is used, also save a list of

footnotes as a separate WordPerfect file. When the final draft is

ready for review, save the text, tables, figure captions, footnotes,

and front matter as separate document files.

Tables should be prepared using all tabs or all spaces

between columnar data, but not a combination of the two.

Figures must be original (even if oversized) and on paper; they

cannot be photocopies (e.g., Xerox) unless that is all that is

available, nor be on disk. Except under extraordinary circumstances, color will not be used in illustrations.

Manuscript Submission

Authors must submit one paper copy of the double-spaced

manuscript, one magnetic copy on a disk, and original figures (if

applicable). NEFSC authors must include a completely signedoff 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

Northeast Fisheries Science Center

National Marine Fisheries Service

166 Water Street

Woods Hole, MA 02543-1026 USA
Research Communications Unit

Northeast Fisheries Science Center

National Marine Fisheries Service, NOAA

166 Water St.

Woods Hole, MA 02543-1026

NOAA Technical Memorandum NMFS-NE -- This series is issued irregularly. The series includes: data reports of longterm or large area studies; synthesis reports for major resources or habitats; annual reports of assessment or monitoring programs;

documentary reports of oceanographic conditions or phenomena; manuals describing field and lab techniques; literature surveys of major

resource or habitat topics; findings of task forces or working groups; summary reports of scientific or technical workshops; and indexed

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

free copies are available from authors or the NEFSC. Issues are also available from the National Technical Information Service, 5285

Port Royal Rd., Springfield, VA 22161.

Fishermen's Report and The Shark Tagger -- The Fishermen's Report (FR) is a quick-turnaround report on the

distribution and relative abundance of commercial fisheries 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 the FR; copies are available

through free subscription. The Shark Tagger (TST) is an annual summary of tagging and recapture data on large pelagic sharks as derived

from the NMFS's Cooperative Shark Tagging Program; it also presents information on the biology (movement, growth, reproduction, etc.)

of these sharks as subsequently derived from the tagging and recapture data. There is internal scientific review, but no technical or copy

editing, of the TST; copies are available only to participants in the tagging program.

Northeast Fisheries Science Center Reference Document -- This series is issued irregularly. The series

includes: data reports on field and lab observations or experiments; progress reports on continuing experiments, monitoring, and

assessments; background papers for scientific or technical workshops; and simple bibliographies. Issues receive internal scientific review

but no technical or copy editing. No subscriptions. Free distribution of single copies.

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-peer-reviewed 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. Those media are in three categories:

Publications and Reports

of the

Northeast Fisheries Science Center

To obtain a copy of a technical memorandum or a reference document, or to subscribe to the fishermen's report,

write: Research Communications Unit, Northeast Fisheries Science Center, 166 Water St., Woods Hole, MA

02543-1026. An annual list of NEFSC publications and reports is available upon request at the above address.

Any use of trade names in any NEFSC publication or report does not imply endorsement.

STANDARD

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