NOAA Technical Memorandum NMFS-NE-125

Essential Fish Habitat Source Document:

Atlantic Halibut, Hippoglossus

hippoglossus,

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:

Atlantic Halibut, Hippoglossus hippoglossus,

Life History and Habitat Characteristics

Luca M. Cargnelli, Sara J. Griesbach, 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-125
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.........................................................................................................................................................................3

Status of the Stocks ...................................................................................................................................................................................4

Research Needs .........................................................................................................................................................................................4

Acknowledgments.....................................................................................................................................................................................4

References Cited .......................................................................................................................................................................................4

Tables

Table 1. Age and size at maturity of Atlantic halibut, Hippoglossus hippoglossus...............................................................................7

Table 2. Summary of life history and habitat parameters for Atlantic halibut, Hippoglossus hippoglossus..........................................8

Figures

Figure 1. The Atlantic halibut, Hippoglossus hippoglossus (from Goode 1884)..................................................................................10

Figure 2. Abundance (% occurrence) of the major prey items in the diet of Atlantic halibut from NEFSC trawl surveys...................11

Figure 3. Distribution and abundance of Atlantic halibut from Newfoundland to Cape Hatteras during 1975-1994...........................12

Figure 4. Distribution of Atlantic halibut larvae collected during NEFSC ichthyoplankton surveys, 1977-1991................................13

Figure 5. Distribution of juvenile and adult Atlantic halibut collected during NEFSC bottom trawl surveys, 1963-1997 ..................14

Figure 6. Abundance of juvenile and adult Atlantic halibut relative to water temperature and depth based on NEFSC surveys.........15

Figure 7. Commercial landings and survey indices for Atlantic halibut in the Gulf of Maine and Georges Bank................................16

Figure 8. Length distribution of Atlantic halibut caught in NEFSC trawl surveys during 1988-1998 .................................................17
Page 1

INTRODUCTION

The Atlantic halibut, Hippoglossus hippoglossus, is

the largest of all flatfish (Figure 1). It is found on both

sides of the North Atlantic Ocean and in parts of the

Arctic Ocean. A directed fishery for Atlantic halibut in

U.S. waters began in the early 19th century and peaked

from 1845 to 1900 (A.B. Howe, Massachusetts Division

of Marine Fisheries, personal communication). By the

1940’s it had collapsed and for many years there was no

directed Atlantic halibut fishery in U.S. waters.

Consequently, no management plan was developed for the

species.

Currently, a small-scale fishery for “chicken” halibut

(3.6-6.8 kg) exists off the coast of Maine. The September

1997 ‘Status of Fisheries of the United States’ (National

Marine Fisheries Service 1997) reports that the U.S.

Atlantic halibut population is currently in an overfished

condition, and the New England Fishery Management

Council intends to place Atlantic halibut within the

Northeast Multispecies Fishery Management Plan

(NEFMC 1996).

This Essential Fish Habitat Source Document

provides information on the life history and habitat

characteristics of Atlantic halibut.

LIFE HISTORY

A synopsis of the life history of Atlantic halibut is

presented here. More detailed information is provided in

reviews by Haug (1990), Trumble et al. (1993), and

Collette and Klein-MacPhee (in prep.).

EGGS

The halibut egg is among the largest of planktonic

fish eggs (Russell 1976). Fertilized halibut eggs in the

western Atlantic have a diameter of 3-4 mm (Fahay 1983;

Scott and Scott 1988; Miller et al. 1991). In Norway,

eggs range from 2.86-2.98 mm (Trumble et al. 1993) to

3.06-3.49 mm (Haug et al. 1984).

The eggs are bathypelagic, floating not at the surface,

but rather, suspended in the water column at depths

ranging from 54 m (Scott and Scott 1988) to 200 m

(Blaxter et al. 1983). In the eastern Atlantic, eggs rise for

2-4 days after deposition to a depth of neutral buoyancy

(Haug 1990; Trumble et al. 1993). Laboratory studies

indicate that eggs are neutrally buoyant at salinities of 35-

37 ppt (Blaxter et al. 1983; Trumble et al. 1993);

however, this is considerably higher than salinities found

on the continental shelves of the North Atlantic. Thus,

eggs are negatively buoyant due to their high organic

matter content (Riis-Vestergaard 1982) and sink towards

the bottom where development is thought to proceed

(Blaxter et al. 1983). In northern Norway, eggs were

found at intermediate depths, temperatures of 4.5-7o

C, and

salinities of 33.8-35.0 ppt (Haug et al. 1984). The

incubation period is strongly temperature-dependent,

lasting from 13-20 days at 4.7-7o

C (Miller et al. 1991;

Collette and Klein-MacPhee, in prep.).

LARVAE

Information on larvae is scarce since they have been

difficult to catch in sufficient numbers (Haug 1990;

Trumble et al. 1993). The 6 to 7 mm long larvae

(Lonning et al. 1982; Blaxter et al. 1983) hatch at an early

stage of development, with no pigment, functional eyes or

mouth, and possess a very large yolk sac (Blaxter et al.

1982; Lonning et al. 1982; Haug 1990). Little

information on the distribution of the pelagic stages is

known, but larvae are thought to remain close to the water

surface until metamorphosis (Nickerson 1978). Browns

Bank may be a significant rearing area for young Atlantic

halibut (Neilson et al. 1993).

The larval development period is long. Exogenous

feeding commences 28-35 days after hatching, and the

yolk sac is completely absorbed 50 days after hatching at

5.3o

C (Blaxter et al. 1983), at which point the larvae are

11.5-13.0 mm in length (Pittman et al. 1987).

Metamorphosis begins with the migration of the left eye

about 80 days after hatching, at a length of about 20 mm

at 6o

C (Pittman et al. 1987). Settlement occurs at 34-40

mm, prior to completion of eye movement and

metamorphosis is complete by approximately 50 mm

(Haug 1990). However, Nickerson (1978) reports that the

left eye completes its migration one year after hatching, at

a length of 10 cm, at which point settlement to the bottom

occurs.

JUVENILES

In the western Atlantic, juveniles are known to exist

in distinct nursery grounds (Haug 1990; Miller et al.

1991). Metamorphosis into the adult stage begins at a

length of approximately 24 mm and, depending on

temperature, after approximately 90 days of development.

Transformation is complete by 4-10 cm, and may take up

to one year (Miller et al. 1991).

ADULTS

Atlantic halibut show considerable sexual

dimorphism in size at length, with females attaining a

substantially larger size than males (McCracken 1958;

Bowering 1986). Sizes as large as 3 m in length and 300

kg in weight, and ages of 50 years have been documented

(Trumble et al. 1993). During the height of the halibut

fishery in the 19th century, the average size of females
Page 2

was 100 to 150 pounds and males rarely exceeded 50

pounds (Goode 1884). More recent studies report smaller

sizes: Bowering (1986) reported captures of males up to

189 cm and females up to 229 cm in length off

Newfoundland, and Miller et al. (1991) reported females

up to 220 cm and 35 years of age. Most halibut caught in

recent years weighed less than 100 kg (Nickerson 1978).

In the northeast Atlantic, adults are thought to leave

spawning areas and disperse randomly, apparently in

search of food (Haug 1990), to shallow and deep waters

as well as inshore and offshore areas (Godø and Haug

1988). Similar observations have been made in North

American waters (McCracken 1958; Bowering 1986).

Stobo et al. (1988) hypothesized that larger, sexually

mature halibut (i.e., adults) exhibit limited dispersal and

an annual return migration to spawning grounds.

REPRODUCTION

The age and size at maturity of Atlantic halibut vary

considerably; females mature at a much larger size and

older age than males (Table 1).

Atlantic halibut are annual, group-synchronous

spawners (Neilson et al. 1993). Females are batch

spawners, able to ovulate several batches of eggs in a

single reproductive season (Methven et al. 1992).

Depending on body size, females can produce from 0.5-7

million eggs in a single season (Haug and Gulliksen

1988). Spawning in the western Atlantic is believed to

occur on the slopes of the continental shelf and on the

offshore banks (McCracken 1958; Nickerson 1978;

Neilson et al. 1993), at depths of at least 183 m (Scott and

Scott 1988), over rough or rocky bottom (Collins 1887).

In Norwegian coastal waters, halibut spawning has been

reported over soft clay or mud bottom, in deepwater (300-

700 m) locations at temperatures ranging from 5-7o

C and

salinities of 34.5-34.9 ppt (Haug 1990).

Spawning occurs during late winter and early spring

(McCracken 1958; Scott and Scott 1988; Miller et al.

1991; Methven et al. 1992; Trumble et al. 1993), with

peak spawning having been reported during November to

December (Neilson et al. 1993). Kohler (1964) reported

that spawning occurred during winter to early spring on

the Scotian Shelf, during February to April in the Gulf of

St. Lawrence, and during winter to late spring off

Newfoundland (Kohler 1964). In northern Norway,

spawning has been reported during December to March,

with peak spawning at the end of January/beginning of

February (Haug 1990). However, historical descriptions

of spawning have reported ripe halibut as late as August

(Goode 1884).

FOOD HABITS

The diet of Atlantic halibut changes with increasing

size. Fish up to 30 cm in length feed almost exclusively

on invertebrates, mainly annelids and crustaceans (crabs,

shrimps); those 30-80 cm in length feed on both

invertebrates (mainly crustaceans, some mollusks) and

fish; and those greater than 80 cm in length feed almost

exclusively on fish (Kohler 1967). In the Gulf of Maine,

the most important prey of adult halibut during 1977-1980

were squid (Illex), crabs (Cancer), and fish (silver hake,

northern sand lance, ocean pout, and alewife) (Collette

and Klein-MacPhee, in prep.). Maurer and Bowman

(1975) report that 91% of the stomach contents of juvenile

and adult halibut (by weight) were fish (> 50% were

longhorn sculpin and its eggs, but also cod and other

gadids), and 8% were crustaceans. Nickerson (1978)

reports that the fish prey of halibut includes cod, cusk,

haddock, ocean perch, sculpins, silver hake, herring,

capelin, skates, flounder and mackerel.

The Northeast Fisheries Science Center (NEFSC)

bottom trawl survey data on food habits [see Reid et al.

(1999) for details] show a similar ontogenetic shift in the

diet of Atlantic halibut (Figure 2). The 1973-1980 data

clearly illustrate that, while crustaceans dominate the diet

of smaller halibut, fish increase in importance with size to

dominate the diets of larger halibut (Figure 2a). Halibut

21-30 cm in length fed exclusively on crustaceans,

especially decapods. Those 31-80 cm in length fed on

crustaceans (45%, mostly decapods), fish (33%, including

gadids and clupeids), and mollusks (6.5%, all

cephalopods). The occurrence of fish and mollusks

(cephalopods) in the diet of 81-120 cm halibut increased

to 50% and 17% respectively, while the occurrence of

crustaceans decreased to 25%. The 1981-1990 data show

a similar trend (Figure 2b). The diet of 31-80 cm halibut

was dominated by crustaceans (66%, mostly decapods);

fish and mollusks comprised 25% and 4% respectively.

The diet of 81-134 cm long halibut was almost exclusively

comprised of fish (80%), but also included decapods

(20%, all Majidae).

MIGRATION

Juveniles start to emigrate from nursery areas when

the fish are 3-4 years old (Haug and Sundby 1987). They

then undergo a period during which most movement

occurs; juveniles (< 75 cm) undergo greater migrations

than adults (Stobo et al. 1988). Although most tagging

study recaptures have been made within the same main

region where the juvenile fish were tagged, very long

distance migrations have been documented from Labrador

to the western coast of Greenland (Godø and Haug 1988),

the Gulf of St. Lawrence to Iceland (McCracken and

Martin 1955), the Scotian Shelf to the Grand Bank

(Jensen and Wise 1961; Kohler 1964; Stobo et al. 1988),
Page 3

and the western coast of Greenland to the Grand Bank

(Godø and Haug 1988). Extensive migrations have also

been documented from northern Norway to the White Sea,

Iceland and Greenland, from the Faroe Islands to the

North Sea and Iceland, and from Iceland to the Faroe

Islands, Greenland and Newfoundland (Haug 1990).

HABITAT CHARACTERISTICS

Detailed information on the habitat characteristics of

Atlantic halibut follows and is summarized in Table 2.

EGGS AND LARVAE

The eggs of Atlantic halibut are spawned at

temperatures of 4-7o

C (Miller et al. 1991), depths as deep

as 700 m (Blaxter et al. 1983), salinities of # 35 ppt

(Blaxter et al. 1983; Haug et al. 1986), and on harder

substrates of sand, gravel, and clay (Collette and KleinMacPhee, in prep.). The larvae are pelagic, floating

within 50 m of the surface (Nickerson 1978), are buoyant

at salinities of 34.8-36.4 ppt, and prefer salinities in the

30-34 ppt range (Blaxter et al. 1983).

JUVENILES AND ADULTS

Juvenile Atlantic halibut are quite localized, being

found in apparently well-defined nursery grounds and in

coastal areas 20-60 m deep with sandy bottoms (Haug

1990). Stobo et al. (1988) hypothesize that the area

around Sable Island Gully on the Scotian Shelf may serve

as a nursery area for juveniles before they begin their

dispersive phase. Juveniles are able to survive sub-zero

temperatures, but prefer temperatures > 2o

C (Goff et al.

1989). Adults are found over sand, gravel or clay

substrates (Collette and Klein-MacPhee, in prep.), at

temperatures ranging from -0.5 to 13.6o

C (Mahon 1997).

However, most are caught within 3-9o

C, and generally

prefer temperatures > 4o

C (McCracken 1958; Bowering

1986). They are typically found at depths of 100-700 m

(720-900 m is their depth limit) (Bowering 1986, Miller et

al. 1991), and most commercial catches are made at

depths of 200-300 m (Scott and Scott 1988).

Most of the Atlantic halibut taken during the NEFSC

trawl surveys (see Geographical Distribution below) were

at temperatures of 4-13 oC and depths of 25-200 m.

GEOGRAPHICAL DISTRIBUTION

Atlantic halibut in the northwest Atlantic were

distributed from north of Labrador south to Long Island

during 1975-1994 (Figure 3). The areas of highest

abundance of the species seem to be along the southern

edge of the Grand Bank and on the Scotian Shelf from

Browns Bank to Banquereau Bank. This corresponds to

their accepted center of abundance (Trumble et al. 1993).

In U.S. waters, halibut are found on the northeast part of

Georges Bank, Nantucket Shoals, Stellwagen Bank, and

off the coast of Maine and Massachusetts. Although

Atlantic halibut have been taken as far south as Virginia,

these are few and considered stragglers from the main

population (Smith et al. 1975).

In Canadian waters, historical distributions of

Atlantic halibut ranged along the entire coast of Labrador

and Newfoundland, the Gulf of St. Lawrence, the eastern

shores of Nova Scotia, and the Bay of Fundy. In U.S.

waters, halibut were abundant on Georges Bank,

Nantucket Shoals, and between Gloucester and Cape Cod,

Massachusetts, and were occasionally found as far south

as New Jersey (Goode 1884, 1887).

EGGS AND LARVAE

No Atlantic halibut eggs were captured during the

1977-1991 NEFSC offshore ichthyoplankton surveys.

They are negatively buoyant and thought to develop on or

near the sea bed (Riis-Vestergaard 1982; Blaxter et al.

1983) and thus are not sampled in the ichthyoplankton

surveys.

Larvae were captured at only two of 1,672 stations

sampled during the NEFSC ichthyoplankton surveys [see

Reid et al. (1999) for details], on the northeast part of

Georges Bank, and near Petit Manan Island off the eastern

coast of Maine (Figure 4). This is not surprising since

very few larvae have ever been captured in the wild (Haug

1990) and since spawning is believed to no longer occur

in the Gulf of Maine (Collette and Klein-MacPhee, in

prep.).

JUVENILES AND ADULTS

NEFSC Bottom Trawl Survey

In the western Atlantic, juveniles are typically found

on the southwestern Scotian Shelf, but rarely off

Newfoundland, supporting the view that the former is an

important rearing or nursery area (Neilson et al. 1993).

Catches of juvenile and adult Atlantic halibut from the

1963-1997 NEFSC bottom trawl surveys [see Reid et al.

(1999) for details] are presented in Figure 5. Halibut were

caught in low numbers from throughout the Gulf of Maine

area, as far south as Nantucket Shoals; a single halibut

was caught southwest of Cape Cod. The highest

concentrations were found in Canadian waters, on Browns

Bank and off southwestern Nova Scotia. In U.S. waters,

lower concentrations were found on the northern slope of

Georges Bank, Nantucket Shoals, Stellwagen Bank, and

off the coast of Maine. There does not appear to be a
Page 4

significant seasonal effect on distribution and abundance

(Figure 5).

There was a definite seasonal effect on the

temperature inhabited by Atlantic halibut (Figure 6). In

spring, > 70% of halibut were caught at 4-6o

C, while in

autumn, > 65% were caught at 9-13o

C. Similarly, Scott

and Scott (1988) found that commercial catches were

most common at 3-9o

C. Halibut were caught at depths

ranging from 25-200 m, with the majority caught between

50-100 m (Figure 6). In spring, > 65% were found at

75-100 m, whereas in autumn, > 70% were caught at

50-75 m. Miller et al. (1991) states that Atlantic halibut

in the western North Atlantic have been found over depths

ranging from 37-1000 m.

Massachusetts Inshore Trawl Survey

Only 18 Atlantic halibut (all juveniles, 19-75 cm in

length) have been taken in Massachusetts inshore waters

between 1978 and 1997.

STATUS OF THE STOCKS

Historical landings of Atlantic halibut in the Gulf of

Maine/Georges Bank area are presented in Figure 7. In

1900, landings had already declined 95% from 1879

levels (A.B. Howe, Massachusetts Division of Marine

Fisheries, personal communication), and catches have

since declined even further.

Prior to 1930, landings were variable, but often

exceeded 600 metric tons (mt) annually, and catches

exceeding 800 mt were common. Since then, landings

have exceeded 400 mt only twice, and have generally

been well below 200 mt. Landings averaged 756 mt per

year from 1893 to 1930 (516 mt if the two especially high

years are omitted), compared to only 164 mt annually

from 1931 to the present. Since 1953 U.S. landings have

been 100 mt or below, and have hit historical lows in

recent years. Canadian landings in area 5 were more than

twice the U.S. landings in the 1960’s, but have since also

declined considerably. Currently, the area of highest

exploitation of the species in the northwestern Atlantic is

the Scotian Shelf area (Neilson et al. 1993).

NEFSC survey indices have fluctuated considerably

since the 1960’s (Figure 7), and overall, have declined

considerably. Mean weight per tow during spring surveys

has remained at an historic low since 1988. During both

spring and autumn surveys, mean number per tow has

been considerably higher than mean weight per tow,

indicating a decrease in the size of halibut. In fact, based

on size, almost all halibut caught in the NEFSC surveys

from 1988-1998 were juveniles (Figure 8).

The September 1997 ‘Status of Fisheries of the

United States’ (National Marine Fisheries Service 1997)

reports that the U.S. Atlantic halibut population is

currently in an overfished condition.

RESEARCH NEEDS

• There is very little information in the published

literature on the biology of northwest Atlantic stocks

(relative to European stocks), and almost no

information from U.S. waters.

• Information on the egg and larval stages is very

scarce. They have proven to be very difficult to catch

in large enough numbers to be useful (Haug 1990).

More directed sampling effort, better sampling

techniques, and better information about the location

of spawning events are required. Data on these

highly dispersive, pelagic stages are important to

understanding recruitment and stock structure.

• Information on the spawning event and the location of

spawning sites is vague.

• Information on the migratory patterns of juveniles is

lacking. It is believed that the juvenile stage is highly

dispersive, but no migration patterns have been

shown.

• Mapping of size groups relative to habitat types (e.g.,

bottom type) based on groundfish survey catches

would be of great benefit to defining EFH for the

species.

• Improved information on the onset of maturity and

stock identification (e.g., genetic differentiation of

stocks) is required.

ACKNOWLEDGMENTS

The authors wish to thank Donna Johnson for

producing the larval distribution map and Joseph

Vitaliano for providing the food habits data. Steven

Murawski and Arnold Howe provided excellent comments

and historical information which improved this document.

REFERENCES CITED

Blaxter, J.H.S., D. Danielssen, E. Mokness and V.

Øiestad. 1983. Description of the early development

of the halibut Hippoglossus hippoglossus and

attempts to rear the larvae past first feeding. Mar.

Biol. 73: 99-107.

Bowering, W.R. 1986. The distribution, age and growth

and sexual maturity of Atlantic halibut (Hippoglossus

hippoglossus) in the Newfoundland and Labrador

area of the northwest Atlantic. Can. Tech. Rep. Fish.

Aquat. Sci. 1432: 1-34.

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

Atlantic halibut, Hippoglossus hippoglossus

(Linnaeus 1758). In B.B. Collette and G. Klein-
Page 5

MacPhee eds. Bigelow and Schroeder’s fishes of the

Gulf of Maine. Smithsonian Institution Press,

Washington, DC.

Collins, J.W. 1887. Historical notes and incidents of the

fresh-halibut fishery. In G.B. Goode ed. The fisheries

and fishery industries of the United States. Section II:

A geographical review of the fisheries industries and

fishing communities for the year 1880. Govt. Print.

Office, Washington, DC.

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.

Godø, O.R. and T. Haug. 1988. Tagging and recapture of

Atlantic halibut (Hippoglossus hippoglossus L.) on

the continental shelves off eastern Canada, and off

western and eastern Greenland. J. Northwest Atl.

Fish. Sci. 8: 25-31.

Goff, G.P., D.A. Methven, and J.A. Brown. 1989. Low

temperature tolerance of Atlantic halibut,

Hippoglossus hippoglossus, at ambient ocean

temperatures in Newfoundland. Proceedings of the

Annual Meeting, Aquaculture Association of Canada.

89-3: 53-55.

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.

Goode, G.B. 1887. The fisheries and fishery industries of

the United States. Section II: A geographical review

of the fisheries industries and fishing communities for

the year 1880. Govt. Print. Office, Washington, DC.

Haug, T. 1990. Biology of the Atlantic halibut,

Hippoglossus hippoglossus (L. 1758). Adv. Mar.

Biol. 26: 2-70.

Haug, T. and B. Gulliksen. 1988. Fecundity and oocyte

sizes in ovaries of female Atlantic halibut Hippoglossus hippoglossus (L.). Sarsia 73: 259-261.

Haug, T., E. Kjørsvik, and P. Solemdal. 1986. Influence

of some physical and biological factors on the density

and vertical distribution of Atlantic halibut

Hippoglossus hippoglossus eggs. Mar. Ecol. Prog.

Ser. 33: 207-216.

Haug, T., E. Kjørsvik, and P. Solemdal. 1984. Vertical

distribution of Atlantic halibut (Hippoglossus

hippoglossus) eggs. Can. J. Fish. Aquat. Sci. 41: 798-

804.

Haug, T. and S. Sundby. 1987. A preliminary report on

the natural occurrence and ecology of Atlantic

halibut, Hippoglossus hippoglossus, postlarvae and

young immature stages. ICES C.M. F: 38. 29 p.

Jensen, A.C. and J.P. Wise. 1961. Movement of tagged

halibut off New England - II. Trans. Am. Fish. Soc.

90: 489-490.

Kohler, A.C. 1964. Movements of halibut on the Nova

Scotian and Grand Banks. J. Fish. Res. Board Can.

21: 837-840.

Kohler, A. C. 1967. Size at maturity, spawning season,

and food of Atlantic halibut. J. Fish. Res. Board Can.

24: 53-66.

Lonning, S., E. Kjørsvik, T. Haug, and B. Gulliksen.

1982. The early development of the halibut, Hippoglossus hippoglossus (L.), compared with other

marine teleosts. Sarsia 67: 85-91.

Mahon, R. 1997. Demersal fish assemblages from the

Scotian Shelf and Bay of Fundy, based on trawl

survey data (1970-1993). Can. Manuscr. Rep. Fish.

Aquat. Sci. 2426. 38 p.

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

marine fishes of the northwest Atlantic - data report.

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

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

McCracken, F.D. 1958. On the biology and fishery of the

Canadian Atlantic halibut, Hippoglossus

hippoglossus L. J. Fish. Res. Board Can. 15: 1269-

1311.

McCracken, F.D. and W.R. Martin. 1955. Recent

recoveries of tagged halibut. Fish. Res. Board Can.,

Atlantic Prog. Rep. 61: 4.

Methven, D.A., L.W. Crim, B. Norberg, J.A. Brown, G.

Goff, and I. Huse. 1992. Seasonal reproduction and

plasma levels of sex steroids and vitellogenin in

Atlantic halibut (Hippoglossus hippoglossus). Can. J.

Fish. Aquat. Sci. 49: 754-759.

Miller, J.M., J.S. Burke, and G.R. Fitzhugh. 1991. Early

life history patterns of Atlantic North American

flatfish: likely (and unlikely) factors controlling

recruitment. Neth. J. Sea Res. 27: 261-275.

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.

1996. Final Amendment #7 to the Northeast

Multispecies Fishery Management Plan incorporating

the supplemental environmental impact statement

Vol. I. February 1996. NEFMC. [Saugus, MA.]

Neilson, J.D., J.F. Kearney, P. Perley, and H. Sampson.

1993. Reproductive biology of Atlantic halibut

(Hippoglossus hippoglossus) in Canadian waters.

Can. J. Fish. Aquat. Sci. 50: 551-563.

Nickerson, J.T.R. 1978. The Atlantic halibut and its

utilization. Mar. Fish. Rev. 40(7): 21-25.

Pittman, K., L. Berg, and K. Naas. 1987. Morphological

development of halibut (Hippoglossus hippoglossus)

larvae with special reference to mouth development

and metamorphosis. ICES C.M. F:18. 22 p.

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.

Riis-Vestergaard, J. 1982. Water and salt balance of
Page 6

halibut eggs and larvae (Hippoglossus hippoglossus).

Mar. Biol. 70: 135-139.

Russell, F.S. 1976. The eggs and planktonic stages of

British marine fishes. Academic Press, London. 524

p.

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

preferences of common fishes of the Scotian Shelf. J.

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

Scott, W.B. and M.G. Scott. 1988. Atlantic fishes of

Canada. Can. Bull. Fish. Aquat. Sci. 219. 731 p.

Smith, W.G., J.D. Sibunka, and A. Wells. 1975. Seasonal

distributions of larval flatfishes (Pleuronectiformes)

on the continental shelf between Cape Cod, Massachusetts, and Cape Lookout, North Carolina, 1965-

66. NOAA Tech. Rep. NMFS SSRF-691. 68 p.

Stobo, W.T., J.D. Neilson, and P.G. Simpson. 1988.

Movements of Atlantic halibut (Hippoglossus

hippoglossus) in the Canadian North Atlantic. Can. J.

Fish. Aquat. Sci. 45: 484-491.

Trumble, R.J., J.D. Neilson, W.R. Bowering, and D.A.

McCaughran. 1993. Atlantic halibut (Hippoglossus

hippoglossus) and Pacific halibut (H. stenolepis) and

their North American fisheries. Can. Bull. Fish.

Aquat. Sci. 227, 84 p.

Wise, J.P. and A.C. Jensen. 1959. Movement of tagged

halibut off New England. Trans. Am. Fish. Soc. 88:

357-358.
Page 7

Table 1. Age and size at maturity of Atlantic halibut, Hippoglossus hippoglossus.

Location A50 (years) L50 (cm) Reference

male Female male female

Scotian Shelf, Grand Bank - - 66-70 100 Kohler (1967)

Newfoundland, Labrador 8 12 80 125 Bowering (1986)

Western North Atlantic - 7-12 - 105-150 Miller et al. (1991)

Grand Bank, Newfoundland - - 80* 115-120* Methven et al. (1992)

*minimum length at maturity
Page 8

Table 2. Summary of life history and habitat parameters for Atlantic halibut, Hippoglossus hippoglossus.

Life Stage Size and Growth Habitat Substrate Temperature

Eggs 1

Eggs are spherical and large. Average egg

diameter (post-fertilization) = 3-4 mm.

Average incubation = 18 days at 5o

C.

Norwegian studies show eggs achieve higher

specific gravity with age (i.e., become less

buoyant).

Unfertilized eggs are not buoyant, but sink to

bottom where they are fertilized by males.

Norwegian studies show vertical distribution

of eggs associated with hydrography. In areas

with strongly defined pycnocline, vertical

distribution had one clear peak; in areas with

less defined pycnocline and weaker

stratification, vertical distribution less

distinct. In well-stratified areas, older eggs

found deeper than younger eggs (but not in

more mixed areas).

Optimal temperatures in

lab experiments: 5 and

7oC.

Incubation time to 50%

hatch varies with

temperature: 20 days at

4.7o

C, 18 days at 5oC,

and 13 days at 7oC.

Larvae 2

Hatch at an immature stage, with no

pigmentation and mouth closed, and very

large yolk sac, at size of: 6-7 mm length.

Norwegian studies found larvae are able to

feed 28-35 days post-hatch at 5o

C (still with

large yolk sac), at a body length of 11 mm;

yolk sac resorption complete after 50 days

post-hatch at 5.3o

C; growth 0.1mm/d up to

day 50. Metamorphosis begins with left eye

migration at ~2 cm.

Larvae are pelagic and tend to rise toward

surface and drift inshore until

metamorphosis. The smallest bottom stages

collected from waters < 50 m.

Juveniles 3

Metamorphosis begins at ~24 mm, at ~90

days. Transformation complete by 4-10 cm

and up to 1 year.

Juveniles are most common in shallow water,

20-60 m, in Atlantic Canada. Nursery areas

located on the shelf; Sable Island Gully area

may serve as nursery area before juveniles

begin their dispersive phase.

In a Newfoundland

laboratory study,

juveniles were able to

survive extended periods

at subzero winter

temperatures in good

condition. Became

inactive and ceased to

feed at temps < 2.0o

C.

Adults 4

Historically halibut caught off US east coast

weighed up to > 300 kg; more recently < 100

kg.

In NF and Labrador males range from 40-189

cm TL (majority 50-79 cm); females range

from 40-229 cm TL (majority 80-89 cm).

Full grown females in the Gulf of Maine

average 45.5-68 kg. Female max. age/size =

35 yrs/220 cm; male max. size = 89% of

female size at same age.

Growth: females grow faster and attain larger

size than males. Halibut older than 10 years

exhibit a more rapid rate of growth than any

other flatfish.

Maturity: males mature at an earlier age than

females. SS: male L50=66-70 cm, female L50=

100 cm; NW Atlantic: female A50=7-12 yrs,

L50=105-150 cm; NF/Labrador: male L50=8

yrs, A50=80 cm, first appeared sexually

mature at 40-59 cm (4 yrs), all mature by

110-119 cm; female A50=12 yrs, L50=125 cm;

first mature at 50-79 cm (6 yrs), all were

mature by 130-149 cm; GrB: males first

mature at 80 cm, females first mature at 115-

120 cm.

Range from Labrador shelf, along edges of

the Grand Bank, outer Scotian Shelf and

Georges Bank, south to Virginia (but very

few south of Long Island). Range from 37-

1000 m; depth limit uncertain.

Gulf of Maine: shift from deeper waters in

winter to shallower in summer, food supply

influences seasonal distribution.

Scotian Shelf: found mainly on banks and in

the head of the BF, in deeper waters, 165-229

m; most abundant in deep water in spring and

early fall, shallower in summer (< 37 m);

commercial catches most common at 200-

300 m.

Newfoundland/Labrador: most abundant in

deepwater channels (100-700 m); absent from

shallower areas and along coastline; peak

numbers caught in Aug.; max. abundance

during Jan-June at 501-600 m, and during

July-Dec at 300-500 m.

Usually found

on sand, gravel

or clay; not on

soft mud or on

rock bottom.

Found at temperatures

ranging from -0.5 to

13.6o

C, avoid < 2.5oC.

Most halibut caught

within temperatures of 3-

9o

C, average 5-6oC.

1 Nickerson (1978), Blaxter et al. (1983), Haug et al. (1986), Scott and Scott (1988), Miller et al. (1991), Collette and Klein-MacPhee (in prep.) 2 Nickerson (1978), Blaxter et al. (1983), Collette and Klein-MacPhee (in prep.) 3

 Nickerson (1978), Scott and Scott (1988), Goff et al. (1989), Miller et al. (1991), Stobo et al. (1993) 4

 McCracken (1958), Kohler (1967), Nickerson (1978), Scott (1982), Bowering (1986), Scott and Scott (1988), Miller et al. (1991), Methven et al. (1992), Neilson et al.

 (1993), Stobo et al. (1993), Mahon (1997), Collette and Klein-MacPhee (in prep.)
Page 9

Table 2. cont’d.

Life Stage Salinity Prey Predators Spawning Notes

Eggs 1

Various reports of neutral

buoyancy of eggs at 34.7-36.5

ppt; thus at lower salinities

eggs are negatively buoyant

and thought to develop on or

near the sea bed. Norwegian

studies show negative

buoyancy is due to high

organic matter content of the

egg; older eggs found at

higher salinities (i.e., greater

depths) than earlier egg stages

in well-stratified areas.

High specific density

of eggs is a possible

adaptation to reduce

mortality; i.e.,

sinking eggs are less

vulnerable to

predation near sea

floor than in pelagic

zone.

Spawning occurs at great

depths (see adults section for

details).

Very large eggs are unusual

when compared to most

other marine teleosts. Eggs

bathypelagic: they’re

buoyant but don’t float at

surface; drift suspended in

water column (> 54-90 m

in the Gulf of Maine). Tend

to sink toward bottom as

development proceeds.

Larvae 2

Norwegian lab experiments

have shown that salinities of

30-35 ppt are preferred and

that larvae are neutrally

buoyant in 35.8 ppt sea water

at hatching, in 34.8 ppt on

day 12, and in 36.4 ppt on

day 35.

Long time to first

exogenous feeding and in

general long period of

larval development is

unusual compared to other

marine fish larvae in this

part of the Atlantic.

Juveniles 3

The juvenile phase is when

most movement occurs.

The area near BB may

serve as a nursery area for

immature halibut; tagging

data suggests that many NF

fish originated from BB

nursery area.

Adults 4

Scotian Shelf: found at

salinities ranging from 30.4-

35.3 ppt, average ~33 ppt.

Voracious feeders. Diet

changes with size:

1) up to 30 cm: almost

exclusively

invertebrates, mainly

annelids and

crustaceans, also

mollusks;

2) 30-80 cm:

invertebrates, fish or

both;

3) > 80 cm: almost

exclusively fish.

Most important prey in

GM (1977-1980) were

squid (Illex), crabs

(Cancer), silver hake,

northern sand lance,

ocean pout, and

alewife.

Other commonly eaten

fish species: cod, cusk,

haddock, ocean perch,

sculpins, herring,

capelin, skates,

flounder and mackerel.

Halibut are a staple

for Greenland sharks

(Somniosus

microcephalus); also

preyed on by seals

and spiny dogfish

(Squalus acanthus).

Spawning grounds not well

known; various spawning

areas from Georges Bank to

Grand Bank; no longer any

spawning population in the

Gulf of Maine.

Believed to occur on the

slopes of offshore banks as

well as on the continental

slope.

Depths of spawning not

clear but are thought to

spawn in deep waters (> 180

m, to 700 m), on the bottom.

Time of spawning: a)

Scotian Shelf: winter-early

spring (mostly Feb-April); b)

Gulf of St. Lawrence: FebApril; c) Newfoundland:

winter-later spring; d)

Browns Bank to Grand

Bank: peaks Nov-Dec.

Large females may produce

up to 2 million eggs; can

spawn numerous batches of

eggs within a single

reproductive season.

Halibut in the GM are

thought to originate from

halibut immigrating from

east and north of Cape

Sable rather than from local

production. Smaller fish

generally exhibit more

extensive movement than

adults. Typically not highly

migratory; most fish remain

in main shelf areas where

they are tagged.

Recaptures show movement

to east; deepwater crossing

of channels probable.

Some movement from sw

NS to GB and GrB

(distance traveled ranges

from 161-968 km); possible

return to SS for spawning.

Capable of extensive

movement; one fish tagged

in GSL recovered in Iceland

(1600 miles away).

1 Riis-Vestergaard (1982), Blaxter et al. (1983), Haug et al. (1986), Scott and Scott (1988), Collette and Klein-MacPhee (in prep.) 2 Blaxter et al. (1983) 3 Neilson et al. (1993), Stobo et al. (1993) 4

 McCracken and Martin (1955), McCracken (1958), Wise and Jensen (1959), Jensen and Wise (1961), Kohler (1964, 1967), Maurer and Bowman (1975), Nickerson (1978),

 Riis-Vestergaard (1982), Scott (1982), Godo and Haug (1988), Scott and Scott (1988), Miller et al. (1991), Methven et al. (1992), Neilson et al. (1993), Stobo et al. (1993),

 Mahon (1997), Collette and Klein-MacPhee (in prep.)
Page 10

Figure 1. The Atlantic halibut, Hippoglossus hippoglossus (from Goode 1884).
Page 11

Figure 2. Abundance (% occurrence) of the major prey items in the diet of Atlantic halibut from NEFSC trawl surveys.

Methods for sampling, processing, and analysis of samples differed between the time periods [see Reid et al. (1999) for

details]. The category “unknown animal remains” refers to unidentifiable animal matter.

Crustacea 45.2%

Fish 33.3%

Cephalopoda 6.5%

All Other Groups 15.1%

Crustacea 25.0%

Fish 50.0%

Cephalopoda 16.7%

Unknown Animal Remains 8.3%

Paguridae 31.3%

Crustacea 20.8%

Fish 25.0% Decapoda Crab 14.6%

Cephalopoda 4.2%

All Other Groups 4.2%

Unknown Fish 60.0%

Gadus morhua 20.0%

Majidae 20.0%

31-80 cm

(n = 66)

81-120 cm

(n = 8)

31-80 cm

(n = 33)

81-134 cm

(n = 5)

a) 1973-1980

b) 1981-1990
Page 12

Figure 3. Distribution and abundance of Atlantic halibut 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 13

Figure 4. Distribution of Atlantic halibut larvae collected during NEFSC ichthyoplankton surveys, 1977-1991 [see Reid

et al. (1999) for details]. Larval densities are represented by dot size; the 60 and 200 m contour lines are also shown.

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

35

36

37

38

39

40

41

42

43

44

45

 Ichthyoplankton Surveys

61-cm Bongo Net; 0.505-mm mesh

April (1977 to 1991)

Atlantic Halibut

Number of Tows = 1672, with larvae = 2

1 to 6

Number of Larvae / 10m2
Page 14

Figure 5. Distribution of juvenile and adult Atlantic halibut collected during NEFSC bottom trawl surveys (winter,

spring, summer, and autumn, 1963-1997). Densities (number per tow) 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

All Lengths

= Absent

 = Present

Atlantic Halibut

Number/Tow

 1 to <2

 2 to <3

 3 to <5

 5 to <10

 10 to <15

NMFS Trawl Surveys

Spring 1968 - 97

All Lengths

Atlantic Halibut

NMFS Trawl Surveys

Summer 1963 - 95

All Lengths

= Absent

 = Present

Atlantic Halibut

Number/Tow

 1 to <2

 2 to <3

 3 to <4

 4 to <6

 6 to <8

NMFS Trawl Surveys

Autumn 1963 - 96

All Lengths

Atlantic Halibut
Page 15

Figure 6. Abundance of juvenile and adult Atlantic halibut relative to water temperature and depth based on spring and

autumn NEFSC trawl surveys (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 16

Figure 7. Commercial landings (1893-1997) and survey indices (1963-1997) for Atlantic halibut in the Gulf of Maine

and Georges Bank.
Page 17

Figure 8. Length distribution of Atlantic halibut caught in NEFSC trawl surveys during 1988-1998.
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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