NOAA Technical Memorandum NMFS-NE-131

Essential Fish Habitat Source Document:

Pollock, Pollachius virens,

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:

Pollock, Pollachius virens,

Life History and Habitat Characteristics

Luca M. Cargnelli, Sara J. Griesbach, David B. Packer,

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

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-131
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 ..............................................................................................................................................................................2

Geographical Distribution.........................................................................................................................................................................3

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

Research Needs .........................................................................................................................................................................................5

Acknowledgments.....................................................................................................................................................................................5

References Cited .......................................................................................................................................................................................5

Tables

Table 1. Size and age at maturity of U.S. pollock, Pollachius virens.......................................................................................................8

Table 2. Summary of life history and habitat parameters for pollock, Pollachius virens.........................................................................9

Figures

Figure 1. The pollock, Pollachius virens (from Goode 1884) ..............................................................................................................11

Figure 2. Summary of the early life history of pollock .........................................................................................................................12

Figure 3. Pollock spawning locations based on the distribution of eggs and larvae from ichthyoplankton surveys.............................13

Figure 4. Abundance of the major prey items in the pollock diet from NEFSC bottom trawl survey data on food habits ...................14

Figure 5. Distribution and abundance of polluck from Newfoundland to Cape Hatteras during 1975-1994 .......................................15

Figure 6. Distribution of pollock eggs collected during NEFSC MARMAP offshore ichthyoplankton surveys..................................16

Figure 7. Abundance of pollock eggs relative to water temperature and depth based on NEFSC MARMAP surveys.........................19

Figure 8. Distribution of pollock larvae collected during NEFSC MARMAP offshore ichthyoplankton surveys ...............................20

Figure 9. Abundance of pollock larvae relative to water temperature and depth based on NEFSC MARMAP surveys ......................23

Figure 10. Distribution of juveniles and adults collected during NEFSC trawl surveys.........................................................................24

Figure 11. Abundance of juvenile and adult pollock relative to water temperature and depth based on NEFSC surveys......................26

Figure 12. Distribution of juvenile and adult pollock collected during Massachusetts inshore trawl surveys........................................27

Figure 13. Abundance of juvenile and adult pollock relative to water temperature and depth based on Massachusetts surveys ...........28

Figure 14. Occurrence of pollock in Narragansett Bay during 1990-1996 based on Rhode Island bottom trawl surveys......................29

Figure 15. Commercial landings and survey indices of pollock for Gulf of Maine, Georges Bank and the Scotian Shelf.....................30
Page 1

INTRODUCTION

The pollock, Pollachius virens (Figure 1), is a gadoid

species inhabiting both sides of the North Atlantic. In the

northwest Atlantic they are most common on the Scotian

Shelf, Georges Bank, in the Great South Channel, and in

the Gulf of Maine. There is considerable movement of

the species between the Scotian Shelf, Georges Bank and

the Gulf of Maine. Thus, although some differences in

meristic and morphometric characters have been shown,

there are no significant genetic differences among areas

(Mayo et al. 1989). As a result, the Scotian Shelf,

Georges Bank and the Gulf of Maine pollock (NAFO

divisions 4V, 4W, 4X and subareas 5, 6) are assessed as a

single unit. In U.S. waters, the species is managed under

the New England Fishery Management Council’s

Northeast Multispecies Fishery Management Plan

(NEFMC 1993).

This Essential Fish Habitat source document provides

information on the life history and habitat requirements of

pollock inhabiting the Gulf of Maine, Georges Bank, and

the Scotian Shelf.

LIFE HISTORY

A brief synopsis of the life history characteristics of

pollock is provided in Amendment #5 to the Northeast

Multispecies Fishery Management Plan (NEFMC 1993).

More detailed information is provided here and in reviews

by Bigelow and Schroeder (1953), Hardy (1978), and

Collette and Klein-MacPhee (in prep.).

EARLY LIFE HISTORY

Pollock eggs are buoyant, rising into the water

column after fertilization. The pelagic larval stage lasts

for three to four months, at which time the small juveniles

or “harbor pollock” migrate inshore where they inhabit

rocky subtidal and intertidal zones. They undergo a series

of inshore-offshore movements linked to temperature

(Ojeda and Dearborn 1990; Rangeley and Kramer 1995;

Collette and Klein-MacPhee, in prep.) until near the end

of their second year (summarized in Figure 2). At this

point the juveniles move offshore where they remain

throughout the adult stage.

ADULTS

Adult pollock can attain maximum lengths of 120 cm,

but are usually less than 110 cm (Collette and KleinMacPhee, in prep.). A maximum age of 18 years has been

recorded, although the major portion of the catch consists

of 3-6 year old fish (Mayo 1994). Growth rate is rapid

until sexual maturity, at which time it declines (Steele

1963). Pollock are a schooling species and are found

throughout the water column (Hardy 1978). With the

exception of short migrations due to temperature changes

and north-south movements for spawning, pollock are

fairly stationary in the Gulf of Maine and along the Nova

Scotian coast (Hardy 1978; Collette and Klein-MacPhee,

in prep.).

REPRODUCTION

Male pollock reach sexual maturity at a larger size

and older age than females (Table 1). Age and size at

maturity of pollock have declined in recent years, a trend

which has also been reported in other marine fish species

(e.g., haddock, witch flounder). During 1985-1990, male

and female pollock attained sexual maturity more than a

year earlier than during 1970-1984. Data from the Bay of

Fundy (Steele 1963) provide further evidence of a decline:

during 1960-1961, females attained maturity at 62.5 cm

and 5-7 years, and males attained maturity at 58 cm and 4-

7 years. The decline in size and age at maturity is

potentially an effect of size-selective overfishing and/or

recent declines in stock abundance or density (see Status

of the Stocks below).

The principal pollock spawning sites in the northwest

Atlantic are in the western Gulf of Maine, Great South

Channel, Georges Bank, and on the Scotian Shelf (Figure

3). In the Gulf of Maine, spawning is concentrated in

Massachusetts Bay, Stellwagen Bank, and from Cape Ann

to the Isle of Shoals (Steele 1963; Hardy 1978; Collette

and Klein-MacPhee, in prep.). Spawning is believed to

occur throughout the Scotian Shelf; Emerald, LaHave, and

Browns banks are the principal sites (Mayo et al. 1989).

Spawning takes place from September to April.

Spawning time is more variable in northern sites than in

southern sites. In the Gulf of Maine spawning occurs

from November to February (Steele 1963; Colton and

Marak 1969), peaking in December (Collette and KleinMacPhee, in prep.). On the Scotian Shelf, spawning

occurs from September to April (Markle and Frost 1985;

Clay et al. 1989) and peaks from December to February

(Clay et al. 1989).

Spawning occurs over hard, stony or rocky bottom

(Hardy 1978). Spawning activity begins when the water

column cools to near 8o

C, and peaks when temperatures

are approximately 4.5-6o

C (Collette and Klein-MacPhee,

in prep.). Thus, most spawning occurs within a

comparatively narrow range of temperatures. There is

little information on salinity, but in Massachusetts Bay,

spawning is reported to occur at salinities of 32-32.8 ppt

(Collette and Klein-MacPhee, in prep.).
Page 2

FOOD HABITS

Pollock initially inhabit the water column and

therefore feed on pelagic prey. The primary prey of small

larvae (4-18 mm) are larval copepods (Marak 1960;

Steele 1963) while larger larvae (> 18 mm) feed primarily

on adult copepods (Marak 1960). The primary prey of

juvenile pollock are crustaceans. Euphausiids, in

particular Meganyctiphanes norvegica, are the most

important crustacean prey of juveniles (Tyler 1972;

Bowman and Michaels 1984; Collette and KleinMacPhee, in prep.). Fish and mollusks make up a smaller

proportion of the juvenile diet (Bowman and Michaels

1984); however, in some cases fish may play a more

important role in the diet. For example, Ojeda and

Dearborn (1991) reported that the diet of subtidal

juveniles in the Gulf of Maine was dominated by fish,

especially young Atlantic herring (Clupea harengus). The

diet of adults is comprised of, in order of decreasing

importance, euphausiids, fish and mollusks (Steele 1963;

Bowman and Michaels 1984; Collette and KleinMacPhee, in prep.). M. norvegica is the single most

important prey item and Atlantic herring is the most

important fish species. Bowman and Michaels (1984)

found that the diet preferences of adults vary with size:

crustaceans were the most important prey item among

smaller adults (41-65 cm), fish were most important

among medium size adults (66-95 cm), and mollusks (the

squid Loligo) were the most important prey among the

largest adults (> 95 cm).

The 1973-1990 Northeast Fisheries Science Center

(NEFSC) bottom trawl survey data on food habits [see

Reid et al. (1999) for details] verify that crustaceans,

especially M. norvegica, are the most important prey item

of juvenile and adult pollock (Figure 4). The 1973-1980

data indicate that juveniles fed primarily on crustaceans

(56%), but also on nematodes (10%), fish (9%) and

annelids (4%) (Figure 4a). Crustaceans were also the

most important food item of adults. However, they were

less common than for juveniles (37% vs. 56%), while fish

(16%) and nematodes (15%) were more common in the

adult diet. The 1981-1990 data also indicate that

crustaceans are the most important food item of pollock,

and that fish are more important in the diet of adults than

juveniles (Figure 4b). Crustaceans (mostly euphausiids)

made up 69% of the juvenile diet and 60% of the adult

diet. Fish comprised only 12% of the juvenile diet, but

made up 28% of the adult diet. Sand lance (Ammodytes

sp.) was the most common fish prey for both juveniles and

adults, and Atlantic herring were also common.

STOCK STRUCTURE

Tagging studies have shown that there is considerable

movement of pollock across the Scotian Shelf and the

Gulf of Maine (Mayo et al. 1989). For most of the year,

adult pollock undergo minor inshore-offshore movements

linked to temperature (Collette and Klein-MacPhee, in

prep.). However, mixing of stocks occurs in winter when

adults undergo migrations to the spawning grounds. For

example, Bay of Fundy pollock are thought to migrate

south or southeast and spawn with fish from the Gulf of

Maine and possibly the Scotian Shelf (Steele 1963). Eggs

and larvae undergo significant movement away from the

spawning area as they drift with currents (Hardy 1978).

For example, larvae from the northern Gulf of Maine are

thought to originate from spawning grounds in the

southern Gulf of Maine (Bigelow and Schroeder 1953).

Thus, although some morphometric and meristic

differences have been reported among pollock from

different areas, electrophoretic analyses show no

significant genetic differences (Mayo et al. 1989).

There is evidence that different age classes do not

mix, forming large size-segregated schools throughout the

water column (Hardy 1978). In the Bay of Fundy, 0+ and

1+ schools are distinct, with 1+ juveniles inhabiting

slightly deeper water (Steele 1963).

HABITAT CHARACTERISTICS

Information on the habitat characteristics of pollock

is presented here and is summarized in Table 2. This

information is restricted to pollock inhabiting U.S. waters

and the Scotian Shelf in Canadian waters since they are

considered a single stock for assessment and management

purposes (Mayo et al. 1989). Information from other

stocks (e.g., European) was not considered.

EGGS

Pollock eggs are spawned over broken substrate at

salinities of 32-32.8 ppt (Collette and Klein-MacPhee, in

prep.). They are pelagic and free-floating, usually found

in water 50-250 m in depth (Hardy 1978).

Pollock eggs taken during NEFSC Marine Resources

Monitoring, Assessment and Prediction (MARMAP)

ichthyoplankton surveys (see Geographical Distribution

below) were at temperatures ranging from 2-17o

C,

although most were at temperatures of 5-11o

C. Eggs were

taken at depths ranging from 30-270 m, but most were at

50-90 m (Figure 7).

LARVAE

Larvae are also pelagic, commonly found at

temperatures of 3-9o

C (Bigelow and Schroeder 1953), and

normally occur from the shore out to the 200 m depth

contour, but have been reported in waters as deep as 1550

m (Hardy 1978).

Pollock larvae taken during MARMAP
Page 3

ichthyoplankton surveys (see Geographical Distribution

below) were at temperatures ranging from 2-17o

C, but this

varied seasonally and temperatures of 5-10o

C were most

common. Larvae were taken at depths ranging from 10 to

> 1000 m, but most were at 50-90 m (Figure 9).

JUVENILES

Juveniles have been reported over a wide variety of

substrates, including sand, mud, or rocky bottom and

vegetation (Hardy 1978). They are found at temperatures

ranging from 0-16o

C and prefer salinities of around 31.5

ppt (Hardy 1978). Inshore subtidal and intertidal zones

are utilized by age 0+ and 1+ juveniles and serve as

important nursery areas (Steele 1963; Ojeda and Dearborn

1990; Rangeley and Kramer 1995). Age 2+ juveniles

move offshore, inhabiting depths of 130-150 m (Steele

1963).

Juvenile haddock taken during NEFSC trawl surveys

(see Geographical Distribution below) were at

temperatures ranging from 1-18o

C, but most were taken at

3-12o

C. They were taken at depths ranging from 5-125 m,

but most were taken at 25-75 m (Figure 11). Juveniles

taken during Massachusetts trawl surveys (see

Geographical Distribution below) were at 6-13o

C and 0-

75 m (Figure 13).

ADULTS

Adults show little preference for bottom type (Scott

1982b). They are found at high salinities, 31-34 ppt

(Scott 1982a), and temperatures of 0-14o

C (Hardy 1978;

Scott 1982a; Collette and Klein-MacPhee, in prep.),

although they tend to avoid temperatures > 11o

C and <

3o

C. They inhabit a wide range of depths, 35-365 m

(Hardy 1978; Scott 1982a), but most occur within the 137

m depth contour and depths of 100-125 m are preferred

(Hardy 1978). Adults tend to inhabit deeper waters in

spring and summer than in winter and they are typically

found further offshore than juveniles (Mayo et al. 1989;

Collette and Klein-MacPhee, in prep.).

Adult haddock taken during NEFSC trawl surveys

(see Geographical Distribution below) were at

temperatures ranging from 1-12o

C, but most were taken at

6-8o

C. Adults were taken at depths ranging from 15-325

m, but most were taken at 75-175 m (Figure 11). Most

adults taken during Massachusetts trawl surveys (see

Geographical Distribution below) were at 5-7o

C and 10-

30 m (Figure 13).

GEOGRAPHICAL DISTRIBUTION

Pollock in the northwest Atlantic were distributed

from the Delmarva Peninsula north to the Gulf of St.

Lawrence and the Grand Banks during 1975-1994 (Figure

5). The areas of highest abundance of the species are the

Scotian Shelf and the Gulf of Maine.

EGGS

The 1978-1987 MARMAP offshore ichthyoplankton

surveys [see Reid et al. (1999) for details] collected eggs

during October to June from off Delaware Bay to

southwest Nova Scotia (Figure 6). Highest monthly mean

egg densities occurred in November (24.4 eggs/10 m2

),

December (36.8 eggs/10 m2

), January (86.1 eggs/10 m2)

and February (19.6 eggs/10 m2

) in Massachusetts Bay,

Georges Bank, and Browns Bank. Egg densities were

considerably lower in months prior to and after this period

(≤ 1.40 eggs/m2

). This concurs with reports that peak

spawning occurs during November to February (Hardy

1978; Fahay 1983; Clay et al. 1989).

Eggs were collected at temperatures ranging from

about 2-17o

C (Figure 7). From October to February, eggs

were found at increasingly lower temperatures, with most

eggs found at 10-11o

C in October and most eggs found at

5-6o

C in February. From March to June the majority of

eggs were found at temperatures from around 5-7o

C.

Optimal development of eggs occurs at 3.3-8.9o

C (Hardy

1978).

Eggs were found over depths ranging from 30-270 m,

but the majority of eggs were collected at a more

restricted range, 50-90 m (Figure 7). Hardy (1978)

reported that eggs are found in water 50-250 m deep.

LARVAE

The 1977-1987 MARMAP offshore ichthyoplankton

surveys [see Reid et al. (1999) for details] found larvae

during September to July from off Chesapeake Bay to

southwest Nova Scotia (Figure 8). The highest monthly

mean larval densities occurred in December (3.6 larvae/10

m2

), January (9.0 larvae/10 m2) and February (10.3

larvae/10 m2

). Larval densities were considerably lower

in months prior to and after this period (≤ 0.72 larvae/10

m2

). This corresponds to peak spawning occurring from

November to February (Hardy 1978; Fahay 1983; Clay et

al. 1989). The highest densities in December and January

appear to be in Massachusetts Bay, Georges Bank, and the

western edge of Browns Bank; by Febraury the highest

abundances are in Massachusetts Bay, off the east coast of

Cape Cod, and in the vicinity of Jeffreys Ledge.

Larvae were collected within a temperature range of

about 2-17o

C (Figure 9). There appears to be a seasonal

difference in larval occurrence with bottom temperatures.
Page 4

In fall, larvae were found at temperatures of 8-17o

C.

Larvae were bimodally distributed relative to temperature

in October and November. In winter, larvae were found at

colder temperatures, approximately 2-13o

C. In spring and

summer larvae were collected in slightly warmer

temperatures ranging from 3-15o

C, although the majority

were at 5-10o

C.

Larvae were collected at depths ranging from 10-250

m from October to July (Figure 9). For most of the year,

the majority of larvae were found at 50-90 m. Hardy

(1978) reported that larvae are normally found out to the

200 m depth contour, but that they have been found as

deep as 1550 m.

JUVENILES

NEFSC Bottom Trawl Surveys

In the winter, NEFSC bottom trawl surveys [see Reid

et al. (1999) for details] captured juveniles from

throughout the Gulf of Maine, Browns Bank, and along

the edges of Georges Bank (Figure 10). In summer, they

were spread along the inshore areas of the Gulf of Maine,

off the coast of Rhode Island and Long Island, the western

edge of the Great South Channel, off Massachusetts, and

the northern edge of Georges Bank. In spring, the highest

densities of pollock were found along the fringes of the

Gulf of Maine, as well as the western edge of the Great

South Channel, the northeastern edge of Georges Bank,

Browns Bank, and southwest Nova Scotia. Densities were

similar in the autumn, with highest densities in

Massachusetts Bay.

Juveniles were found at temperatures ranging from 1-

18o

C, although most were found at 4-12oC (Figure 11).

There is a slight seasonal difference in juvenile

occurrence with bottom temperatures: juveniles were

found at colder temperatures in spring than in autumn. In

the spring > 60% were collected at temperatures of around

4-6o

C, while in autumn > 60% were collected at

temperatures of 8-11o

C (Figure 11). Murawski and Finn

(1988) found a similar trend for age 0+ and age 1+

juveniles.

In the spring and fall, juveniles were caught at depths

ranging from 5-250 m, but most were found between 25-

75 m (Figure 11).

Massachusetts Inshore Trawl Survey

In spring, the 1978-1996 Massachusetts inshore

surveys [see Reid et al. (1999) for details] captured high

densities of juveniles north of Cape Ann, in the vicinity of

Boston Harbor, and the western shore of Martha’s

Vineyard (Figure 12). In the autumn, densities were lower

and juveniles were concentrated around the tip of Cape

Cod (Figure 12). Juveniles were more abundant in

inshore Massachusetts waters in spring than in autumn.

There is a seasonal difference in juvenile occurrence

with bottom temperature. Juveniles were found over a

wider range of temperatures in spring than in autumn. In

the spring, juveniles occurred primarily between 6-13o

C,

while in the fall they occurred mostly at temperatures

between 8 and 11o

C (Figure 13).

There is also a seasonal difference in juvenile

occurrence with depth, with slightly deeper waters

inhabited in autumn. In the spring, juveniles were found

from 0-75 m, but roughly 90% of juveniles were caught at

depths of # 20 m. In autumn they occurred from 0-70 m

with 40% caught at 45 m (Figure 13).

Rhode Island Bottom Trawl Survey

A total of only 336 pollock, all juveniles, were caught

in Narragansett Bay from 1990-1996 [see Reid et al.

(1999) for details]. They were caught in all seasons, but

the vast majority (97%) were caught in spring (Figure 14).

Connecticut Fisheries Division Survey

Pollock are not commonly caught in the surveys of

Long Island Sound, and none have been recorded since

1989 (Gottschall et al., in review). In surveys conducted

from 1984-1990 throughout Long Island Sound, just 24

juveniles were caught. All were caught during summer

(July-August), at all depths and bottom types except sand.

ADULTS

NEFSC Bottom Trawl Survey

In winter, NEFSC bottom trawl surveys [see Reid et

al. (1999) for details] captured adults mostly in the

offshore regions of the Gulf of Maine, Great South

Channel, and along the northern edges of Georges Bank

(Figure 10). The distribution of adults was similar in

summer, although they were also present in nearshore

areas of the Gulf. In spring, adult pollock were spread

throughout the Gulf of Maine with highest densities in the

central Gulf, along the northeastern edge of Georges

Bank, the Great South Channel, and Browns Bank. In

autumn, the highest densities of adults were in the

southwestern Gulf of Maine, the northeastern edge of

Georges Bank, and Browns Bank. Adults were distributed

further south in winter and spring than in summer and

autumn.

Adults were found at temperatures of 1-12o

C (Figure

11). There does not appear to be a significant seasonal

difference in adult occurrence with bottom temperature,

although in spring most adult pollock were found at 6-7o

C

while in autumn most were found at 8o

C. These results
Page 5

support previous reports that adults occur from 1-14o

C

and that temperatures > 3.3o

C are optimal (Collette and

Klein-MacPhee, in prep.).

There also does not appear to be a major seasonal

difference in adult occurrence with depth. Adults were

caught at depths ranging from about 15-325 m, with the

majority at 75-175 m (Figure 11).

Massachusetts Inshore Trawl Survey

Few adults were caught during the spring 1978-1996

Massachusetts inshore surveys [see Reid et al. (1999) for

details]. Those that were caught were mostly found north

of Cape Ann; lower numbers were found in Massachusetts

Bay and around Cape Cod (Figure 12). No adults were

caught in the autumn surveys.

In the spring, adults occurred at temperatures ranging

from 3-13o

C, but approximately 60% were caught at

temperatures of around 5-7o

C (Figure 13). Approximately

55% of adult pollock were caught at depths ranging from

10-30 m, while the remainder were found at 45-75 m

(Figure 13).

STATUS OF THE STOCKS

Commercial catches from the entire Scotian Shelf,

Gulf of Maine and Georges Bank increased from an

annual average of 38,200 mt during 1972-1976 to 68,900

mt during 1986, but have since steadily declined to

historic lows. The total landings in 1996 were 12,300

metric tons (mt), a 7.5% decrease from 1995 (13,300 mt),

a 35% decrease from 1994 (18,900 mt), and a 82%

decrease from the 1986 peak (Figure 15; Mayo 1998).

Total stock size, after increasing throughout the late

1970’s and early 1980’s, has since markedly declined.

Biomass indices for the Gulf of Maine-Georges Bank

increased during the mid-1970’s but declined sharply

during the early 1980’s and have remained low.

Spawning stock biomass increased from 90,000 mt in

1974 to over 200,000 mt in 1985; SSB declined by 36%

between 1986-1991 (Mayo 1995).

The September 1997 report to congress “Status of

Fisheries of the United States” (National Marine Fisheries

Service 1997) reports that the state of overfishing of U.S.

pollock stocks is currently unknown.

RESEARCH NEEDS

Many details of the biology of pollock from the

northwest Atlantic are not well known. No information is

available on the actual spawning event. This is potentially

important information for understanding or modelling the

genetics and population dynamics of pollock stocks.

Information on predation of the various life history stages

is lacking, and data on species interactions in general are

needed. More information is needed on the importance of

inshore areas, specifically rocky subtidal and intertidal

zones and salt marshes, as nursery grounds for juvenile

pollock. A better understanding of the role of these areas

to recruitment and year-class strength is necessary. These

habitats may be critical bottleneck areas.

Finally, the genetic differentiation of stocks should be

investigated further using more advanced and powerful

genetic (e.g., microsatellite DNA markers) and

biochemical (e.g., elemental fingerprinting of otoliths)

techniques. Currently, the management of Gulf of Maine

area pollock as a single unit stock is based on allozyme

electrophoresis analyses which indicate that the stocks are

genetically uniform (Mayo et al. 1989). Newer, more

powerful methods may reveal significant differences.

Most of the available information on northwest

Atlantic pollock is restricted to distribution and

abundance (EFH Level 2). Growth and survival (Level 3)

and production rates (Level 4) by habitat are necessary in

order to accurately designate the essential habitat of

pollock.

ACKNOWLEDGMENTS

The literature review was greatly aided by the draft

update to the Bigelow and Schroeder (1953) section on

pollock provided by Bruce Collette. Joseph Vitaliano

provided gut contents data from the food habits database.

The authors also wish to thank C. Steimle, J. Berrien, and

R. Ramsey-Cross for help with the literature reviews.

REFERENCES CITED

Bigelow, H.B. and W.C. Schroeder. 1953. Fishes of the

Gulf of Maine. U.S. Fish Wildl. Serv., Fish. Bull. 53.

577 p.

Bowman, R.E. and W.L. Michaels. 1984. Food of

seventeen species of northwest Atlantic fish. NOAA

Tech. Mem. NMFS-F/NEC-28. 183 p.

Campana, S.E. 1989. Otolith microstructure of three larval

gadids in the Gulf of Maine, with inferences on early

life history. Can. J. Zool. 67: 1401-1410.

Clay, D., W.T. Stobo, B. Beck, and P.C.F. Hurley. 1989.

Growth of juvenile pollock (Pollachius virens L.)

along the Atlantic coast of Canada with inferences of

inshore-offshore movements. J. Northwest Atl. Fish.

Sci. 9: 37-43.

Collette, B.B. and G. Klein-MacPhee. In preparation.

Pollock, Pollachius virens. In B.B. Collette and G.

Klein-MacPhee eds. Bigelow and Schroeder’s fishes

of the Gulf of Maine. Smithsonian Institution Press,

Washington, DC.

Colton, J.B., Jr. and R.R. Marak. 1969. Guide for

identifying the common planktonic fish eggs and
Page 6

larvae of continental shelf waters, Cape Sable to

Block Island. U.S. Bur. Comm. Fish. Biol. Lab.

Woods Hole Lab. Ref. No. 69-9. 43 p.

Fahay, M.P. 1983. Guide to the early stages of marine

fishes occurring in the western North Atlantic Ocean,

Cape Hatteras to the southern Scotian Shelf. J.

Northwest Atl. Fish. Sci. 4: 1-423.

Goode, G.B. 1884. The fisheries and fishery industries of

the United States. Section I: Natural history of useful

aquatic animals. Govt. Print. Office, Washington,

DC. Plates.

Gottschall, K., M.W. Johnson, and D.G. Simpson. In

review. The distribution and size composition of

finfish, American lobster, and long-finned squid in

Long Island Sound, based on the Connecticut

Fisheries Division bottom trawl survey, 1984-1994.

NOAA Tech. Rep.

Hardy, J.D., Jr. 1978. Development of fishes of the MidAtlantic Bight: An atlas of egg, larval and juvenile

stages. Vol. 2 Anguillidae through Syngnathidae.

U.S. Fish Wildl. Serv. Biol. Serv. Prog. FWS/OBS78/12. 458 p.

Hoberman, J.M. and A.C. Jensen. 1962. The growth rate

of New England pollock. Trans. Am. Fish. Soc. 91:

227-228.

Langton, R.W. and R.E. Bowman. 1980. Food of fifteen

northwest Atlantic gadiform fishes. NOAA Tech.

Rep. SSRF-740. 23 p.

MacDonald, J.S., M.J. Dadswell, R.G. Appy, G.D.

Melvin, and D.A. Methven. 1984. Fishes, fish

assemblages, and their seasonal movements in the

lower Bay of Fundy and Passamaquoddy Bay,

Canada. Fish. Bull. (U.S.) 82: 121-139.

Marak, R.R. 1960. Food habits of larval cod, haddock and

coalfish in the Gulf of Maine and Georges Bank area.

J. Cons. Int. Explor. Mer 25: 147-157.

Markle, D.F. and L.-A. Frost. 1985. Comparative

morphology, seasonality, and a key to planktonic fish

eggs from the Nova Scotian shelf. Can. J. Zool. 63:

246-257.

Maurer, R.O., Jr. and R.E. Bowman. 1975. Food habits of

marine fishes of the northwest Atlantic – data report.

U.S. Natl. Mar. Fish. Serv. Northeast Fish. Cent.

Woods Hole Lab. Ref. Doc. 75-3. 90 p.

Mayo, R. 1994. Life histories and habitat requirements of

demersal fishes. In R.W. Langton, J.B. Pearce, and

J.A. Gibson eds. Selected living resources, habitat

conditions, and human perturbations of the Gulf of

Maine: Environmental and ecological considerations

for fishery management. p. 2-3. NOAA Tech. Mem.

NMFS-NE-106.

Mayo, R. 1995. Pollock. In Conservation and Utilization

Division, Northeast Fisheries Science Center eds.

Status of the fishery resources off the northeastern

United States for 1994. p. 61-63. NOAA Tech. Mem.

NMFS-NE-108.

Mayo, R. 1998. Pollock. In S.H. Clark ed. Status of the

fishery resources off the northeastern United States

for 1998. p. 67-69. NOAA Tech. Mem. NMFS-NE115.

Mayo, R.K., J.M. McGlade, and S.H. Clark. 1989.

Patterns of exploitation and biological status of

pollock (Pollachius virens L.) in the Scotian Shelf,

Georges Bank, and Gulf of Maine area. J. Northwest

Atl. Fish. Sci. 9: 13-36.

Murawski, S.A. and J.T. Finn. 1988. Biological bases for

mixed-species fisheries: species co-distribution in

relation to environmental and biotic variables. Can. J.

Fish. Aquat. Sci. 45: 1720-1735.

National Marine Fisheries Service. 1997. Report to

Congress. Status of fisheries of the United States:

Report on the status of fisheries of the United States.

September 1997. [Homepage of the National Marine

Fisheries Service]. [Online]. Available: http://www.

nmfs.gov/sfa/Fstatus.html.

[NEFMC] New England Fishery Management Council.

1993. Final amendment #5 to the Northeast

Multispecies Fishery Management Plan incorporating

the supplemental environmental impact statement.

Vol. I. September 1993. NEFMC. [Saugus, MA.] 361

p.

O’Brien, L., J. Burnett, and R.K. Mayo. 1993. Maturation

of nineteen species of finfish off the Northeast coast

of the United States, 1985-1990. NOAA Tech. Rep.

NMFS 113. 66 p.

Ojeda, F.P. and J.H. Dearborn. 1990. Diversity,

abundance, and spatial distribution of fishes and

crustaceans in the rocky subtidal zone of the Gulf of

Maine. Fish. Bull. (U.S.) 88: 403-410.

Ojeda, F.P. and J.H. Dearborn. 1991. Feeding ecology of

benthic mobile predators: experimental analyses of

their influence in rocky subtidal communities of the

Gulf of Maine. J. Exp. Mar. Biol. Ecol. 149: 13-44.

Rangeley, R.W. and D.L. Kramer. 1995. Use of rocky

intertidal habitats by juvenile pollock Pollachius

virens. Mar. Ecol. Prog. Ser. 126: 9-17.

Reid, R., F. Almeida, and C. Zetlin. 1999. Essential fish

habitat source document: Fishery independent

surveys, data sources, and methods. NOAA Tech.

Mem. NMFS-NE-122. 39 p.

Rountree, R.A. and K.W. Able. 1992. Fauna of polyhaline

subtidal marsh creeks in southern New Jersey:

composition, abundance and biomass. Estuaries 15:

171-185.

Scott, J.S. 1980. Occurrence of pollock, Pollachius

virens, and sand lance, Ammodytes sp., larvae in the

Bay of Fundy. J. Northwest Atl. Fish. Sci. 1: 45-48.

Scott, J.S. 1982a. Depth, temperature and salinity

preferences of common fishes of the Scotian Shelf. J.

Northwest Atl. Fish. Sci. 3: 29-39.

Scott, J.S. 1982b. Selection of bottom type by

groundfishes of the Scotian Shelf. Can. J. Fish.

Aquat. Sci. 39: 943-947.

Steele, D.H. 1963. Pollock (Pollachius virens (L.)) in the
Page 7

Bay of Fundy. J. Fish. Res. Board Can. 20:

1267-1314.

Tyler, A.V. 1972. Food resource division among northern

marine demersal fishes. J. Fish. Res. Board Can. 29:

997-1003.
Page 8

Table 1. Size and age at maturity of U.S. pollock, Pollachius virens.

Time Period L50 (cm) A50 (years) Reference

Male Female Male Female

1986-1988 41.8 39.1 2.3 2.0 O’Brien et al. 1993

1970-1984 50.5 47.9 3.5 3.2 Mayo et al. 1989
Page 9

Table 2. Summary of life history and habitat parameters for pollock, Pollachius virens. ‘MARMAP’ and ‘NEFSC’ refer

to data discussed in the Geographical Distribution section of this report.

Life

Stage

Size Range and Growth Habitat Substrate Temperature

Eggs 1

Egg diameter ranges from 1.0-

1.22 mm, mean = 1.14 mm.

Eggs are pelagic; usually in water 50-250 m deep.

MARMAP: found at 30-270 m, but most at

50-90 m.

Incubation time ranges from 5 to 15

days; 9-12 days at 6-7o

C, 6 days at

9.4oC; optimal development at 3.3-

8.9oC.

MARMAP: found at 2-17oC, but

most at 5-11oC.

Larvae 2

Size at hatch ranges from 3.0-4.2

mm; mean = 4.0 mm. Size at

transformation ranges from 23-30

mm.

Youngest larvae found nearest the surface.

Normally occur from shore out to the 200 m line,

but reported as deep as 1550 m.

MARMAP: found at 10-1250 m, most at 50-90 m.

From Jan-Feb are found in southern Gulf of Maine

and Cape Cod; from Mar-May are found

throughout the Gulf of Maine and south and east

of Cape Cod.

On the Scotian Shelf, larvae (0.3-1.1 cm) are

offshore in Nov; by May the largest (4.2 cm) start

to move inshore.

One study has reported larvae in the Bay of Fundy;

may be limited to years with high larval

abundance.

In Massachusetts Bay, newly

hatched larvae found in

temperatures ranging from 3-9oC.

MARMAP: found at 2-17oC, most at

5-10oC.

Yolk sac is absorbed in 5 days at

6.1o

C.

Juveniles 3

Overall size range is

approximately 2.5-40 cm.

Descend to bottom at 3-4 months

(< 50 mm length).

Two distinct length groups

inshore during July to November:

(1) first year fish (mean 17-18 cm

by end of 1st year); and (2)

second year fish (mean 27-30 cm

by end of 2nd year).

Average depths inhabited on Georges Bank (m):

age 0: spring: 73, summer: 191, fall: 69; age 1+:

winter: 132, spring: 106, summer: 109, fall: 136.

NEFSC: found at 5-250 m, but most at 25-75 m.

Young juveniles typically found inshore but can

also be found on offshore banks.

In MA Bay swarm at inshore areas after early

April; move offshore in June to avoid warm temps;

return again in fall. But remain abundant inshore

during summer/fall from Cape Ann to Nova

Scotia; seek deeper water in winter.

On the Scotian Shelf, 7-11cm juveniles are inshore

in July; remain inshore until temp drops to < 4o

C

from Jan-April (16-24 cm); return inshore in May

and remain until ~30 cm in their 2nd year.

In the Bay of Fundy, 0+/1+ fish are in the shallow

sublittoral zone by first summer; 20-25 cm fish

move away to deeper water. 2+ fish are found

nearshore or on offshore banks in 130-150 m of

water; move offshore after first summer.

Overwinter in large pelagic schools.

In southern New Jersey, YOY were prominent in

spring collections in subtidal marsh creeks.

Juveniles have

been reported

over substrates

varying from

sand, mud, rocky

bottom or aquatic

vegetation.

In the NW Atlantic, juveniles occur

from 0-15.6o

C.

Average water temp (o

C) for

Georges Bank: age 0: spring 4.4,

summer 8.2, autumn 11.5; age 1+:

winter 4.8, spring 5.5, summer 6.8,

autumn 7.5.

NEFSC: most found at 4-6o

C in

spring and 8-11oC in autumn.

There is evidence for seasonal

inshore-offshore migration linked to

temperature - juveniles in the Gulf

of Maine are more abundant inshore

in summer/fall (warm) than in

winter/spring (cold). Juveniles enter

rocky subtidal zone when

temperatures increase to 8-12o

C and

reach maximum abundance in

midsummer or early fall.

Adults 4

Maximum length is 120 cm, but

usually < 110 cm. Mean length

(1969-1972) in Gulf of Maine

(66.4 cm) was greater than

Georges Bank (38.2 cm) and

western Nova Scotia (44.6 cm).

Sexual maturity:

Bay of Fundy (1960-1961):

female 5-7 yrs, 55-70 cm; male 4-

7 yrs, 50-65 cm.

Gulf of Maine/Scotian Shelf

(1970-1984): female A50=3.2 yrs,

L50= 47.4-47.9 cm; male A50= 3.5

yrs, L50=50.5 cm.

Gulf of Maine/Georges Bank

(1986-1988): female A50=2 yrs,

L50=39.1 cm; male A50=2.3 yrs,

A50=41.8 cm.

Occur from Gulf of St. Lawrence to Cape Lookout,

NC, inshore and on offshore banks, usually at

edges of shoals and banks. Location governed by

prey movements. Commonly range from the

surface to 180 m. NEFSC: found at 15-325 m, but

most at 75-175 m.

Pollock school throughout the water column.

In the Gulf of Maine adults are further offshore

than juveniles and in more specific locations.

From Dec-March adults in western Gulf of Maine

concentrate in relatively shallow water (< 100 m);

in spring/summer they disperse to deeper offshore

waters (100-200 m).

Mean depth of occurrence is greatest in eastern

Scotian Shelf and lowest in Bay of Fundy.

Adults are segregated by size into schools: 65-85

cm off New Brunswick, 60-75 cm near Grand

Manan, NB, and 45-60 cm off western Nova

Scotia.

Pollock are

unselective for

bottom type on

the Scotian Shelf;

associated with

sediments

ranging from

gravels to clay.

Spawning is

generally over

hard bottom near

coastal slopes

and banks.

Occur from 0-14.0o

C; > 3.3oC is

optimal, preferred range 6-10oC.

Large fish avoid the surface when

temperature is > 11.1o

C. Spawning

activity starts when water column

has cooled to ~8.3o

C; peaks at 4.4-

6.1o

C; the majority of egg

production is complete before water

reaches winter minimum of 1.7-

2.2o

C. NEFSC: found at 1-12oC, but

most at 6-8o

C.

1 Colton and Marak (1969), Hardy (1978), Fahay (1983), Markle and Frost (1985), Collette and Klein-MacPhee (in prep.)

2 Bigelow and Schroeder (1953), Steele (1963), Colton and Marak (1969), Hardy (1978), Scott (1980), Fahay (1983), Clay et al. (1989) 3 Steele (1963), Tyler (1972), Hardy (1978), Fahay (1983), MacDonald et al. (1984), Murawski and Finn (1988), Clay et al. (1989), Ojeda and Dearborn (1990), Rountree

 and Able (1992), Rangeley and Kramer (1995), Collette and Klein-MacPhee (in prep.)

4

 Hoberman and Jensen (1962), Steele (1963), Hardy (1978), Langton and Bowman (1980), Scott (1982a, b), Mayo et al. (1989), O’Brien et al. (1993), Collette and Klein-

 MacPhee (in prep.)
Page 10

Table 2. cont’d.

Life

Stage

Salinity Currents Prey Spawning Notes

Eggs 1

In MA Bay,

spawning occurs

at salinities

ranging from

32-32.8 ppt.

Eggs sometimes drift far

from spawning grounds.

Eggs are buoyant, spherical,

transparent, nonadhesive and do not

possess an oil globule.

Hatching peaks in mid-November.

Larvae 2

Small larvae drift with

currents, generally away

from the spawning

grounds. Larger larvae can

direct their movements.

Counter-clockwise

spring/summer circulation

patterns in the Gulf of

Maine, suggest that larvae

off the eastern coast of

Maine probably originate

from spawning grounds off

the western coast of Maine

(south of Cape Elizabeth).

Other studies suggest that

larvae are retained within

the Gulf and on the Scotian

Shelf by the Gulf of Maine

eddy.

Size selective feeders. Larvae

generally ate the most

abundant species of prey

within the appropriate size

range. Primary prey for 4-18

mm larvae were larval

copepods; primary prey for

> 18 mm larvae were adult

copepods.

Drift patterns suggest that

larvae in the Bay of Fundy

region originate from

spawning locations outside

the Bay of Fundy, possibly

in southern Gulf of Maine

and/or the Scotian Shelf.

Pollock migrate inshore as they

grow.

Juveniles 3

In the NW

Atlantic, juveniles

have been found

at salinities

ranging from an

average of 29-32

ppt. 

Drift patterns suggest that

juveniles at the mouth of

the Bay of Fundy originate

from spawning locations

outside the Bay of Fundy,

possibly in southern Gulf

of Maine and/or the

Scotian Shelf.

Crustaceans are the most

important prey (66.1-99.9%

by weight; Euphausiids,

especially Meganyctiphanes

norvegica, are most

important), followed by fish

(0.0-31.0%) and mollusks (0-

1.1%).

Local abundance of juveniles

related to plankton

concentrations.

The intertidal zone may be an

important nursery area; juveniles

present in the shallow intertidal zone

at all stages of the tide throughout

the summer. Subtidal marsh creeks,

such as those in Little Egg Harbor,

NJ, are also seasonally important as

nursery areas.

Size segregation in the Bay of Fundy

shows schooling is an important

aspect of pollock behavior. 0+ and

1+ schools segregated by size, with

1+ in slightly deeper water.

Adults 4

Range 31-34 ppt,

mean 33.7 ppt,

preferred 33-34

ppt (lower in Bay

of Fundy).

In MA Bay,

salinity at

spawning ranges

from 32-32.8 ppt.

Major prey on Georges Bank,

western Nova Scotia and the

Bay of Fundy region are

crustaceans (primarily the

Euphausiid Meganyctiphanes

norvegica) and fish. In the

Gulf of Maine primary prey

are fish (mostly Atlantic

herring, but also pollock,

redfish, hake) and

crustaceans.

On the Scotian Shelf and

Gulf of St. Lawrence fish are

most important.

Diet varies with size of fish:

41-65 cm: crustaceans (31-

97%), fish (0.7-54%) and

mollusks (0-1%); 6-95 cm:

fish (29-74%), crustaceans

(12-63%) & mollusks (0-

12%); > 95 cm: mollusks

(76% Loligo spp.),

crustaceans (15%) & fish

(7%).

Pollock are cannibalistic.

Spawning occurs from SeptApril; peaks in early Nov to

mid-Jan.

Spawn as temperature is

falling, at depths of 42-140

m, possibly to

170 m; but generally

shallower than 110 m.

Spawning locations: from

Nova Scotia to Cape Cod, in

the vicinity of coastal slopes

and banks; highest

concentration is in MA Bay;

also Stellwagen Bank, Cape

Ann to Isle of Shoals,

western Gulf of Maine and

on the Scotian Shelf. Bay of

Fundy and northern Gulf of

Maine pollock probably

spawn in southern Gulf of

Maine and possibly on the

Scotian Shelf.

Pollock complete short migrations

linked to temperature changes and

north-south movements for

spawning. Otherwise, are fairly

stationary in the Gulf of Maine and

along the Nova Scotian coast.

In the summer, Bay of Fundy fish are

a distinct group from w. Nova Scotia

and southern Gulf of Maine fish.

However, in winter, they migrate

south, spawn & probably mix with s.

Gulf of Maine and Scotian Shelf fish.

Growth curves for pollock from the

SW Grand Banks show a faster rate

of growth than those from the Gulf of

Maine. Growth rate is rapid until

sexual maturity, then slows.

Fecundity ranges from 200,000-

8,260,000 eggs.

The primary predator of pollock is

goosefish.

1 Hardy (1978), Fahay (1983), Markle and Frost (1985), Campana (1989), Collette and Klein-MacPhee (in prep.)

2 Bigelow and Schroeder (1953), Marak (1960), Steele (1963), Hardy (1978), Scott (1980), Clay et al. (1989) 3 Steele (1963), Tyler (1972), Bowman and Michaels (1984), Ojeda and Dearborn (1991), Rountree and Able (1992), Rangeley and Kramer (1995), Collette and Klein-

 MacPhee (in prep.)

4 Hoberman and Jensen (1962), Steele (1963), Maurer & Bowman (1975), Hardy (1978), Langton and Bowman (1980), Bowman and Michaels (1984), Mayo et al. (1989),

 Collette and Klein-MacPhee (in prep.)
Page 11

Figure 1. The pollock, Pollachius virens (from Goode 1884).
Page 12

December - January

Peak Spawning

Spawning ranges from September to March1, 2, 3, 4, 5

Eggs hatch in 6-9 days after fertilization3

Resulting larvae are 3.0-4.2 mm2, 4, 6, 7

Transformation occurs at 23-30 mm5,7,8

Remain pelagic for 3-4 months9 (< 50 mm)7

May

Move Inshore

Small juveniles (mean size 3.7-4.2 cm4,10) begin to appear

in the intertidal and subtidal zones11

June

In southern Massachusetts Bay, move offshore to avoid

rising temperatures; return inshore in autumn. However,

north of Cape Ann, remain inshore5

July

Remain Inshore

Range in size from 7-11 cm4

October

Remain Inshore

Average size of 17-18 cm4,10

January

Move Offshore

In large pelagic schools1

When temperatures drop to < 4oC, move to more stable

offshore temperatures4

Range in size from 16-24 cm4

May

Return Inshore

When water temperatures have warmed up4 to > 4oC

Range in size from 20-25 cm5

Size-segregated schools (0+ and 1+ do not mix)1

October

Begin To Move Offshore

Mean length of 27-30 cm4,10 (in Bay of Fundy, 20-25 cm1)

Largest begin to move offshore permanently4,10

Figure 2. Summary of the early life history of pollock. References: 1 Steele (1963), 2 Colton and Marak (1969), 3 Markle

and Frost (1985), 4

 Clay et al. (1989), 5 Collette and Klein-MacPhee (in prep.), 6 Scott (1980), 7 Fahay (1983), 8 Hardy

(1978), 9

 Mayo et al. (1989), 10 Rangeley and Kramer (1995), 11 MacDonald et al. (1984).
Page 13

Figure 3. Pollock spawning locations based upon the distribution of eggs and larvae (number/m2

) from American and

Canadian ichthyoplankton surveys (from Mayo et al. 1989).
Page 14

Figure 4. Abundance (% occurrence) of the major prey items in the pollock diet from NEFSC bottom trawl survey data

on food habits. Methods for sampling, processing, and analysis of samples differed between the time periods [see Reid

et al. (1999) for details]. (a) 1973-1980, 0-40 cm: n=124, 41-110 cm: n=371; (b) 1981-1990, 0-40 cm: n=413, 41-110

cm, n=686. The 0-40 cm size range corresponds, at least roughly, to juveniles, and the 41-110 cm size class corresponds

to adults. The category “animal remains” refers to unidentifiable animal matter.

Crustacea 56.4%

Unkown Animal Remains 11.8%

Nematoda 10.3%

Fish 9.2%

Annelida 4.1%

All Other Groups 8.2%

Crustacea 36.6%

Unknown Animal Remains 24.4%

Fish 16.1%

Nematoda 14.8%

All Other Prey 8.1%

Crustacea 68.9%

Unknown Animal Remains 16.6%

Fish 11.9%

All Other Prey 2.6%

Crustacea 60.3%

Fish 27.9%

Unknown Animal Remains 5.1%

All Other Prey 6.8%

a) 1973-1980

b) 1981-1990

0-40 cm 41-110 cm

0-40 cm 41-110 cm
Page 15

Figure 5. Distribution and abundance of polluck from Newfoundland to Cape Hatteras during 1975-1994. Data are from

the U.S. NOAA/Canada DFO East Coast of North America Strategic Assessment Project (http://www-orca.nos.noaa.

gov/projects/ecnasap/ecnasap_table1.html).
Page 16

Figure 6. Distribution of pollock eggs collected during NEFSC MARMAP offshore ichthyoplankton surveys (October

to December and January to June, 1978-1987). Egg densities are represented by dot size [see Reid et al. (1999) for

details].

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

35

36

37

38

39

40

41

42

43

44

45

Eggs

MARMAP Ichthyoplankton Surveys

Oct to Dec, and Jan to Jun; 1978 to 1987

Number of tows = 7087; with eggs = 588

Pollock

61-cm Bongo Net; 0.505-mm mesh

Eggs / 10m2

1 to <10

10 to <100

100 to <1000

1000 to <10000

10000 to 14886

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

35

36

37

38

39

40

41

42

43

44

45

Eggs

MARMAP Ichthyoplankton Surveys

October; 1978 to 1987

Number of tows = 1044; with eggs = 45

Pollock

Monthly Mean Density = 1.40 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to 185

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

Eggs

MARMAP Ichthyoplankton Surveys

November; 1978 to 1987

Number of tows = 915; with eggs = 102

Pollock

Monthly Mean Density = 24.40 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to <10000

10000 to 10328

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

35

36

37

38

39

40

41

42

43

44

45

Eggs

MARMAP Ichthyoplankton Surveys

December; 1978 to 1987

Number of tows = 569; with eggs = 163

Pollock

Monthly Mean Density = 36.82 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to 2568
Page 17

Figure 6. 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

Eggs

MARMAP Ichthyoplankton Surveys

January; 1978 to 1987

Number of tows = 433; with eggs = 114

Pollock

Monthly Mean Density = 86.08 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to <10000

10000 to 14886

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

35

36

37

38

39

40

41

42

43

44

45

Eggs

MARMAP Ichthyoplankton Surveys

February; 1978 to 1987

Number of tows = 459; with eggs = 76

Pollock

Monthly Mean Density = 19.60 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to <1000

Eggs / 10m2

1000 to 3875

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

35

36

37

38

39

40

41

42

43

44

45

Eggs

MARMAP Ichthyoplankton Surveys

March; 1978 to 1987

Number of tows = 853; with eggs = 29

Pollock

Monthly Mean Density = 0.55 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to 53

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

Eggs

MARMAP Ichthyoplankton Surveys

April; 1978 to 1987

Number of tows = 1020; with eggs = 50

Pollock

Monthly Mean Density = 1.12 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to <100

100 to 399

Eggs / 10m2
Page 18

Figure 6. 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

Eggs

MARMAP Ichthyoplankton Surveys

May; 1978 to 1987

Number of tows = 1085; with eggs = 4

Pollock

Monthly Mean Density = 0.03 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to 15

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

Eggs

MARMAP Ichthyoplankton Surveys

June; 1978 to 1987

Number of tows = 709; with eggs = 5

Pollock

Monthly Mean Density = 0.05 eggs/10m2

61-cm Bongo Net; 0.505-mm mesh

None

1 to <10

10 to 14

Eggs / 10m2
Page 19

Figure 7. Abundance of pollock eggs relative to water temperature (to a maximum of 200 m) and depth based on

NEFSC MARMAP surveys (October to June, 1978-1987). 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

).

June

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

20

40

60

May

0

20

40

60

April

0

20

40

60

March

0

10

20

30

40

February

Percent

0

20

40

60

January

0

20

40

60

December

0

20

40

60

November

0

20

40

60

Pollock Eggs

October

0

10

20

30

40

50

Stations

Egg Catch

January

0

10

20

30

40

50

April

0

10

20

30

40

50

May

0

10

20

30

40

50

June

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

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

0

10

20

30

40

October

0

10

20

30

40

Stations

Egg Catch

Pollock Eggs

February

Percent

0

10

20

40

50

60

March

0

10

20

30

40

50

November

0

10

50

60

70

December

0

10

20

30

40

50
Page 20

Figure 8. Distribution of pollock larvae (< 26.0 mm) collected during NEFSC MARMAP offshore ichthyoplankton

surveys (September to December and January to July, 1977-1987). Larval densities are represented by dot size [see Reid

et al. (1999) for details].

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

Jan. - July & Sept. - Dec. (1977 to 1987)

Pollock

Number of Tows = 10290, with larvae = 407

Larvae <26.0 mm

1 to < 10

10 to < 100

100 to < 1000

1000 to 3742

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

January (1977 to 1987)

Number of Tows = 434, with larvae = 75

Monthly Mean Density = 9.02 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to < 100

100 to 476

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

35

36

37

38

39

40

41

42

43

44

45

February (1977 to 1987)

Number of Tows = 686, with larvae = 73

Monthly Mean Density = 10.29 larvae/10m2

None

1 to < 10

10 to < 100

100 to < 1000

1000 to 3742

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 = 69

Monthly Mean Density = 0.72 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 70
Page 21

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

April (1977 to 1987)

Number of Tows = 1281, with larvae = 84

Monthly Mean Density = 0.70 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 97

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 = 31

Monthly Mean Density = 0.23 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 99

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 = 3

Monthly Mean Density = 0.02 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 12

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 = 2

Monthly Mean Density = 0.01 larvae/10m2

Number of Larvae / 10m2

None

1 to 9
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

September (1977 to 1987)

Number of Tows = 774, with larvae = 1

Monthly Mean Density = 0.01 larvae/10m2

Number of Larvae / 10m2

None

1 to 7

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

35

36

37

38

39

40

41

42

43

44

45

October (1977 to 1987)

Number of Tows = 1147, with larvae = 4

Monthly Mean Density = 0.04 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 26

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

35

36

37

38

39

40

41

42

43

44

45

November (1977 to 1987)

Number of Tows = 1031, with larvae = 23

Monthly Mean Density = 0.23 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to 50

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

35

36

37

38

39

40

41

42

43

44

45

December (1977 to 1987)

Number of Tows = 603, with larvae = 42

Monthly Mean Density = 3.63 larvae/10m2

Number of Larvae / 10m2

None

1 to < 10

10 to < 100

100 to 926
Page 23

Figure 9. Abundance of pollock larvae relative to water temperature (to a maximum of 200 m) and depth based on

NEFSC MARMAP surveys (September to July, 1977-1987). 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

).

January

0

10

20

30

50

April

0

20

40

60

May

0

10

20

30

40

June

0

20

40

60

July

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

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

0

20

40

60

November

0

10

20

Pollock Larvae (<26.0 mm length)

September

0

10

90

100

Stations

Egg Catch

March

0

10

20

30

40

50

October

0

10

20

60

70

February

Percent

0

10

20

60

80

December

0

10

20

30

60

70

January

0

10

20

30

40

April

0

10

20

30

40

December

0

10

20

60

80

Pollock Larvae (<26.0 mm length)

September

0

10

20

80

100

Stations

Larva Catch

May

0

10

20

30

40

June

0

10

20

60

80

July

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

20

40

60

October

0

10

20

50

60

March

0

10

20

30

40

February

Percent

0

10

20

30

60

70

November

0

10

20

30
Page 24

Figure 10. Distribution of juveniles and adults collected during NEFSC trawl surveys (winter, spring, summer, and

autumn, 1963-1997). 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].

Number/Tow

 1 to 10

 10 to 25

 25 to 100

 100 to 500

 500 to 995

NMFS Trawl Surveys

Spring 1968 - 97

Juveniles (<39cm)

Pollock

NMFS Trawl Surveys

Winter 1964 - 97

Juveniles (<39cm)

 = Absent

 = Present

Pollock

Number/Tow

 1 to 10

 10 to 25

 25 to 50

 50 to 100

 100 to 241

NMFS Trawl Surveys

Autumn 1963 - 96

Juveniles (<39cm)

Pollock

NMFS Trawl Surveys

Summer 1963 - 95

Juveniles (<39cm)

= Absent

 = Present

Pollock
Page 25

Figure 10. cont’d.

NMFS Trawl Surveys

Winter 1964 - 97

Adults (>=39cm)

 = Total Tows

 = Positive Tow

Pollock

Number/Tow

 1 to 10

 10 to 50

 50 to 100

 100 to 500

 500 to 1028

NMFS Trawl Surveys

Spring 1968 - 97

Adults (>=39cm)

Pollock

NMFS Trawl Surveys

Summer 1963 - 95

Adults (>=39cm)

= Absent

 = Present

Pollock

Number/Tow

 1 to 10

 10 to 50

 50 to 100

 100 to 500

 500 to 1282

NMFS Trawl Surveys

Autumn 1963 - 96

Adults (>=39cm)

Pollock
Page 26

Figure 11. Abundance of juvenile and adult pollock relative to water temperature and depth based on NEFSC trawl

surveys (spring and autumn, 1963-1997). 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

).
Page 27

Figure 12. Distribution of juvenile and adult pollock collected in inshore waters of Massachusetts during Massachusetts

inshore trawl surveys (spring and autumn, 1978-1996) [see Reid et al. (1999) for details].

Pollock

Mass. Inshore Trawl Survey

 Spring 1978 - 1996

 Juveniles (<39cm)

Number/Tow

 1 to 10

 10 to 25

 25 to 100

 100 to 200

 200 to 460

Pollock

Mass. Inshore Trawl Survey

 Autumn 1978 - 1996

 Juveniles (<39cm)

Number/Tow

 1 to 5

 5 to 10

 10 to 25

 25 to 100

 100 to 196

Pollock

Mass. Inshore Trawl Survey

 Spring 1978 - 1996

 Adult (>=39cm)

Number/Tow

 1 to 2

 2 to 3

 3 to 4

 4 to 5

 5 to 6
Page 28

Figure 13. Abundance of juvenile and adult pollock relative to water temperature and depth based on Massachusetts

inshore surveys (spring and autumn, 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

).
Page 29

Figure 14. Occurrence of pollock in Narragansett Bay during 1990-1996. The numbers shown at each station are the

average catch per tow rounded to one decimal place. Data are from the Rhode Island Division of Fish and Wildlife

bottom trawl surveys conducted each month [see Reid et al. (1999) for details].

0.2

0.0

0.0

0.0

0.1

0.0

0.0

0.0

0.0

0.0

0.0

0.2 0.0

0.0

0.0

0.0

0.0

0.0

0.0

8.9

0.0

0.0

0.1

0.0

5.9 0.0

0.0

0.0

0.1

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0 0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.0

0.1

0.0

0.0 0.0

Spring

Summer Autumn

Winter

Pollock Juveniles (<39cm)

Rhode Island Division of Fish and Wildlife

Trawl Survey of Narragansett Bay 1990 - 1996
Page 30

Figure 15. Commercial landings and survey indices of pollock for Gulf of Maine, Georges Bank and Scotian Shelf,

1963-1996.

Pollock 

Scotian Shelf - Gulf of Maine - Georges Bank

Year

1960 1965 1970 1975 1980 1985 1990 1995 2000

Landings (mt x 1000)

0

10

20

30

40

50

60

70

80

Stratified mean catch/tow (kg)

0

1

2

3

4

5

6

7

8

9

Landings (mt)

Survey index (kg)

Smoothed survey index (kg)
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

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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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