Northern Shortfin Squid, Illex illecebrosus, Life History and Habitat Characteristics

NOAATechnicalMemorandumNMFS-NE-191
U. S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
National Marine Fisheries Service
Northeast Fisheries Science Center
Woods Hole, Massachusetts
November 2004
Essential Fish Habitat Source Document:
Northern Shortfin Squid, Illex illecebrosus,
Life History and Habitat Characteristics
Second Edition

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168. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments – 2001. By Gordon T. Waring, Janeen M. Quintal, and
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104350.
169. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments – 2002. By Gordon T. Waring, Janeen M. Quintal, and
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Blair G. Maise, Wayne E. McFee, Debra L. Palka, Patricia E. Rosel, Marjorie C. Rossman, U.S. Fish and Wildlife Service, Frederick W. Wenzel,
and Cynthia Yeung, contribs. September 2002. vii + 318 p., 42 figs., 56 tables, 4 app. NTIS Access. No. PB2003-104167.
170. Interaction of Shelf Water with Warm-Core Rings, Focusing on the Kinematics and Statistics of Shelf Water Entrained
within Streamers. By Ronald J. Schlitz. March 2003. v + 35 p., 26 figs., 3 tables. NTIS Access. No. PB2005-100158.
171. Length-Weight Relationships for 74 Fish Species Collected during NEFSC Research Vessel Bottom Trawl Surveys. By
Susan E. Wigley, Holly M. McBride, and Nancy J. McHugh. March 2003. vi + 26 p., 1 fig., 3 tables. NTIS Access. No. PB2003-106486.
172. Variability of Temperature and Salinity in the Middle Atlantic Bight and Gulf of Maine Based on Data Collected as
Part of the MARMAP Ships of Opportunity Program, 1978-2001. By Jack W. Jossi and Robert L. Benway. March 2003. vi + 92
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104260.
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By David B. Packer, Christine A. Zetlin, and Joseph J. Vitaliano. March 2003. v + 57 p., 25 figs., 2 tables. NTIS Access. No. PB2003-
104254.
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Location. By Renee Mercaldo-Allen, Margaret A. Dawson, Catherine A. Kuropat, and Diane Kapareiko. September 2003. vi + 20 p., 1
fig., 10 tables. NTIS Access. No. PB2004-107074.
181. In press.
182. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments – 2003. By Gordon T. Waring, Richard M. Pace, Janeen
M. Quintal, Carol P. Fairfield, and Katherine Maze-Foley, eds., Nicole Cabana, Phillip J. Clapham, Timothy V.N. Cole, Gregory L. Fulling,
Lance P. Garrison, Aleta A. Hohn, Blair G. Maise, Wayne E. McFee, Keith D. Mullin, Debra L. Palka, Patricia E. Rosel, Marjorie C. Rossman,
Frederick W. Wenzel, and Amy L. Whitingham, contribs. May 2004. vii + 287 p., 47 figs., 58 tables, 4 app., index. NTIS Access. No.
PB2004-106431.
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NOAATechnicalMemorandumNMFS-NE-191
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Essential Fish Habitat Source Document:
Northern Shortfin Squid, Illex illecebrosus,
Life History and Habitat Characteristics
Second Edition

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Species Names
The NMFS Northeast Region's policy on the use of species names in all technical communications is generally to
followtheAmericanFisheriesSociety's listsofscientificandcommonnamesforfishes( i.e., Robinsetal.1991aa
,bb
),
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),and tofollowtheSocietyfor
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). Exceptionstothis
policyoccurwhentherearesubsequentcompellingrevisionsintheclassificationsofspecies,resultinginchangesinthe
names of species (e.g., Cooper and Chapleau 1998f
;McEachranandDunn1998g
).
aRobins, C.R. (chair); Bailey, R.M.; Bond, C.E.; Brooker, J.R.; Lachner, E.A.; Lea, R.N.; Scott, W.B. 1991a. Common and scientific names
of fishes from the United States and Canada. 5th ed. Amer. Fish. Soc. Spec. Publ. 20; 183 p.
bRobins, C.R. (chair); Bailey, R.M.; Bond, C.E.; Brooker, J.R.; Lachner, E.A.; Lea, R.N.; Scott, W.B. 1991b. World fishes important to
North Americans. Amer. Fish. Soc. Spec. Publ. 21; 243 p.
cTurgeon, 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
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dWilliams, A.B. (chair); Abele, L.G.; Felder, D.L.; Hobbs, H.H., Jr.; Manning, R.B.; McLaughlin, P.A.; Pérez Farfante, I. 1989. Common
and scientific names of aquatic invertebrates from the United States and Canada: decapod crustaceans. Amer. Fish. Soc. Spec. Publ. 17;
77 p.
e
Rice, D.W. 1998. Marine mammals of the world: systematics and distribution. Soc. Mar. Mammal. Spec. Publ. 4; 231 p.
fCooper, J.A.; Chapleau, F. 1998. Monophyly and interrelationships of the family Pleuronectidae (Pleuronectiformes), with a revised
classification. Fish. Bull. (Washington, DC) 96:686-726.
gMcEachran, J.D.; Dunn, K.A. 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs
(Chondrichthyes: Rajidae). Copeia 1998(2):271-290.

Page iii
PREFACE TO SECOND EDITION
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 NOAA Fisheries to assist the
regional fishery management councils in the
implementation of EFH in their respective fishery
management plans.
NOAA Fisheries 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 a series EFH species reports (plus one
consolidated methods report). The EFH species reports
are a survey of the important literature as well as
original analyses of fishery-independent data sets from
NOAA Fisheries and several coastal states. The species
reports are also the source for the current EFH
designations by the New England and Mid-Atlantic
Fishery Management Councils, and understandably
have begun to be referred to as the “EFH source
documents.”
NOAA Fisheries 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.
The initial series of EFH species source documents
were published in 1999 in the NOAA Technical
Memorandum NMFS-NE series. Updating and review
of the EFH components of the councils’ Fishery
Management Plans is required at least every 5 years by
the NOAA Fisheries Guidelines for meeting the
Sustainable Fisheries Act/EFH Final Rule. The second
editions of these species source documents were written
to provide the updated information needed to meet
these requirements. The second editions provide new
information on life history, geographic distribution, and
habitat requirements via recent literature, research, and
fishery surveys, and incorporate updated and revised
maps and graphs. This second edition of the northern
shortfin squid EFH source document is based on the
original by Luca M. Cargnelli, Sara J. Griesbach, and
Christine A. Zetlin, with a foreword by Jeffrey N. Cross
(Cargnelli et al. 1999).
Identifying and describing EFH are the first steps
in the process of protecting, conserving, and enhancing
essential habitats of the managed species. Ultimately,
NOAA Fisheries, 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.

Page v
Contents
INTRODUCTION........................................................................................................................................................................ 1
LIFE HISTORY........................................................................................................................................................................... 1
GEOGRAPHICAL DISTRIBUTION......................................................................................................................................... 3
HABITAT CHARACTERISTICS.............................................................................................................................................. 4
RESEARCH NEEDS................................................................................................................................................................... 6
ACKNOWLEDGMENTS ........................................................................................................................................................... 6
REFERENCES CITED................................................................................................................................................................ 6
Tables
Table 1. Summary of life history and habitat parameters for northern shortfin squid Illex illecebrosus........................12
Figures
Figure 1. The northern shortfin squid, Illex illecebrosus (from Goode 1884)....................................................................14
Figure 2. Hypothetical migration path of the northern shortfin squid, Illex illecebrosus..................................................15
Figure 3. Spawning area of northern shortfin squid (encircled) during late May...............................................................16
Figure 4. Percent by weight (g) of the major prey items in the diet of northern shortfin squid........................................17
Figure 5. Distribution and abundance of northern shortfin squid from Newfoundland to Cape Hatteras........................18
Figure 6. Seasonal distributions and abundances of pre-recruit northern shortfin squid collected during NEFSC
bottom trawl surveys..............................................................................................................................................19
Figure 7. Distribution and abundance of pre-recruit northern shortfin squid in Massachusetts coastal waters...............23
Figure 8. Seasonal distributions and abundances of recruit northern shortfin squid collected during NEFSC bottom
trawl surveys...........................................................................................................................................................24
Figure 9. Distribution and abundance of recruit northern shortfin squid in Massachusetts coastal waters......................28
Figure 10. Distributions of pre-recruit northern shortfin squid and trawls from NEFSC bottom trawl surveys relative to
bottom water temperature, depth, and salinity......................................................................................................29
Figure 11. Distributions of pre-recruit northern shortfin squid and trawls in Massachusetts coastal waters relative to
bottom water temperature and depth. ....................................................................................................................31
Figure 12. Distributions of recruit northern shortfin squid and trawls from NEFSC bottom trawl surveys relative to
bottom water temperature, depth, and salinity......................................................................................................33
Figure 13. Distributions of recruit northern shortfin squid and trawls in Massachusetts coastal waters relative to
bottom water temperature and depth. ....................................................................................................................35

Northern Shortfin Squid, Illex illecebrosus, Life History and Habitat Characteristics

INTRODUCTION
The northern shortfin squid, Illex illecebrosus
(Figure 1), is a highly migratory species of the family
Ommastrephidae. Distributed across a broad
geographic area, I. illecebrosus is found in the
northwest Atlantic Ocean between the Sea of Labrador
and the Florida Straits (66ºN to 29º30'N; Roper et al.
1998). Throughout its range of commercial
exploitation, from Newfoundland to Cape Hatteras,
North Carolina, the population is considered to
constitute a single stock (Dawe and Hendrickson 1998).
The southern stock component (inhabiting U.S. waters)
is managed by the Mid-Atlantic Fishery Management
Council, in accordance with the Atlantic Mackerel,
Squid and Butterfish Fishery Management Plan
(MAFMC 1998), and the northern stock component
(inhabiting waters between Newfoundland and Nova
Scotia) is assessed and managed by the Northwest
Atlantic Fisheries Organization (Hendrickson et al.
2002). Both stock components are managed based on
an annual quota.
This Essential Fish Habitat Source Document
provides information on the life history and habitat
characteristics of northern shortfin squid. Data sources
and methodologies used to prepare this document are
described in Reid et al. (1999).
LIFE HISTORY
The life history characteristics of northern shortfin
squid have been reviewed by Black et al. (1987), Perez
(1994), and O’Dor and Dawe (1998). Most of the
supporting studies have been based on the northern
component of the stock. Like many squid species, I.
illecebrosus lives for less than one year, has a high
natural mortality rate, and exhibits a protracted
spawning season whereby overlapping “microcohorts”
enter the population throughout the year and exhibit
variable growth rates (Caddy 1991; Jackson 1994). The
life cycle is comprised of oceanic and neritic
components. During spring, squid migrate onto the
continental shelf between Newfoundland and Cape
Hatteras. During late autumn, squid migrate off the
continental shelf, presumably to a winter spawning site
(Black et al. 1987). The seasonal proportion of squid
residing beyond the continental shelf is unknown
because this habitat is not sampled during seasonal U.S.
and Canadian bottom trawl surveys. Little is known
about either the habitat of mature individuals
(particularly females) or the winter habitat of the
species.
The life cycle (Figure 2) proposed by Black et al.
(1987) remains hypothetical because several aspects
remain unknown. These include the location of the
winter spawning site, migration patterns between
northern and southern stock components, the autumn
spawning migration route, and what fraction of the
stock inhabits waters beyond the continental shelf.
New life history information regarding population
structure, spawning location, lifespan, and age and size
at maturity are described herein. This new information
is based on data collected on the U.S. shelf during a
stratified, random bottom trawl survey of the population
(Hendrickson 2004).
EGGS AND PARALARVAE
Illex illecebrosus egg masses have never been
collected in the wild (O’Dor and Dawe 1998) but have
been described from laboratory spawning events. The
gelatinous egg balloons are 0.5 to 1.0 m in diameter and
contain between 10,000 and 100,000 eggs (Durward et
al. 1980). Females can produce multiple egg masses
(Durward et al. 1978). Mature eggs are ovoid, ranging
from 0.9 x 0.6 to 1.0 to 0.8 mm in size, and weigh
between 200 and 250 μg (Durward et al. 1980).
Laboratory studies indicate that hatching occurs in
16 days at 13°C, 12 days at 16°C, and 8 days at 21°C;
normal embryonic development requires water
temperatures of at least 12.5°C (O’Dor et al. 1982b).
Paralarvae may remain within the remnants of the egg
mass to utilize the nutrients as a food source (Durward
et al. 1980). In the laboratory, paralarvae hatch at
approximately 1.1 mm mantle length (ML) (Durward et
al. 1980), then enter a transitional stage at
approximately 5.0 mm ML, followed by a juvenile
stage at about 7.0 mm ML (Hatanaka 1986).
Based on the distribution of paralarvae, it is
hypothesized that the Gulf Stream serves as the primary
transport mechanism for egg masses and paralarvae
(O’Dor 1983; Rowell et al. 1985a). Paralarvae have
been collected during all seasons (Roper and Lu 1979),
from south of Cape Hatteras to as far north as the tail of
the Grand Bank (Dawe and Beck 1985; Hatanaka et al.
1985). Paralarvae are most abundant in February and
March, in the nutrient-rich waters of the Gulf
Stream/Slope Water convergence zone; above the
thermocline at temperatures greater than 13°C
(Hatanaka et al. 1985).
I. illecebrosus paralarvae hatched in the laboratory
were 1.10 to 1.25 mm ML (O’Dor et al. 1986). Illex sp.
hatchlings have only been collected in waters south of
Cape Hatteras (35.5ºN) and during February through
March (Dawe and Beck 1985; Rowell et al. 1985a).
However, species identification of Illex paralarvae is
problematic, particularly if caught south of New Jersey,
due to the difficulty in distinguishing between
paralarvae of I. illecebrosus and two sympatric Illex
species (Vecchione and Roper 1986).

JUVENILES AND ADULTS
Onset of the juvenile stage at 8 to 10 mm ML is
indicated by a separation of the proboscis into a pair of
tentacles (Roper and Lu 1979). Juveniles collected in
surveys conducted in the Gulf Stream and continental
slope waters during February through May ranged in
size from 10 to 94 mm ML (O’Dor 1983). During late
spring, juveniles migrate onto the continental shelf
between Nova Scotia and Cape Hatteras (O’Dor 1983;
Black et al. 1987).
Juveniles caught on the continental shelf in late
May ranged in size from 34 to 68 mm ML. Gonadal
development began at about 64 mm ML in males and at
74 mm ML in females. Males attained 50% maturity at
a smaller size and older age than females, but these
differences were not statistically significant. Size- and
age-at-maturity increased with latitude and were
correlated with decreases in water temperature
(Hendrickson 2004). Mean size at maturity may also
vary inter-annually (Coelho and O’Dor 1993). In
inshore Newfoundland waters, the percentage of mature
males and male gonadosomatic indices were
significantly higher for squid hatched in May than
during March or April. Although females do not
become mature in inshore Newfoundland waters, those
hatched in May were more mature than those hatched in
March or April (Dawe and Beck 1997). Captive
females matured within 40 to 60 days (O’Dor et al.
1977).
In Nova Scotian and Newfoundland waters, males
mature at a faster rate than females and are believed to
emigrate during autumn from continental shelf fishing
areas before females (Black et al. 1987). Evidence for
this phenomenon is a seasonal decline in the percentage
of males collected on the Scotian Shelf during some
years (Amaratunga 1980a). However, a reduction in the
proportion of males, which tend to be small individuals,
can also result from cannibalism by larger females
(O’Dor and Dawe 1998). During late autumn, nearly-
mature squid migrate from all continental shelf fishing
areas (Hurley 1980; Black et al. 1987), presumably to
spawn. Most mature females have been collected from
the U.S. shelf (Hendrickson 2004), but four have also
been recorded from waters off the coast of
Newfoundland and Nova Scotia (Dawe and Drew
1981).
Age estimation, accomplished by counting daily
growth increments in the statoliths, has been validated
for I. illecebrosus (Dawe et al. 1985; Hurley et al.
1985). Increment counts of statoliths from mated
females caught in the Mid-Atlantic Bight indicate a
lifespan of about 115 to 215 days (Hendrickson 2004).
Squid inhabiting warmer waters of the Mid-Atlantic
Bight exhibit faster rates of growth and maturation, and
possibly a shorter lifespan, than squid from the northern
stock component (Hendrickson 2004). The species may
achieve a maximum size of 35 cm ML and 700 g, with
females achieving larger sizes than males (Hendrickson
1998; O’Dor and Dawe 1998).
The terms recruit and pre-recruit are used herein to
describe geographical distributions and habitat
characteristics for the exploited and unexploited
portions of the stock, respectively. Exploitation occurs
at a minimum mantle length of 10 cm ML, the
approximate length at which individuals migrate onto
the continental shelf (O’Dor 1983; Hendrickson et al.
1996). Pre-recruits and recruits are thus defined as
individuals ≤ 10 cm ML and ≥ 11 cm ML, respectively.
REPRODUCTION
Mating and spawning have only been observed in
captivity. I. illecebrosus is a semelparous, terminal
spawner whereby spawning and death occur within
several days of mating (O’Dor 1983). Mature females
collected on the U.S. continental shelf had mated with
as many as four males (Hendrickson 2004).
Until recently, few mature females and only two
mated individuals have been recorded (Dawe and Drew
1981). However, back-calculations of hatch dates based
on statolith age analyses indicate that spawning occurs
during October through June (Dawe and Beck 1997;
Hendrickson 2004).
A winter spawning area, located off the east coast
of Florida in the vicinity of the Blake Plateau (Figure 2;
Black et al. 1987), has been inferred based on: the
presence of Illex sp. hatchlings along the north wall of
the Gulf Stream during January and February (Dawe
and Beck 1985; Rowell et al. 1985a; Vecchione and
Roper 1986; Coelho and O’Dor 1993); the offshore
migration of adults in late autumn (Black et al. 1987);
and the presence of minimum water temperatures
required for hatching (O’Dor et al. 1982b; Trites 1983;
Rowell and Trites 1985).
The only confirmed spawning area is located in the
Mid-Atlantic Bight, at depths of 113 to 377 m, where a
large number of mated females were collected between
39º10´N and 35º50´N during late May (Figure 3;
Hendrickson 2004). This spawning area overlaps
spatially with the fishing grounds of the directed fishery
(Hendrickson et al. 1996). Spawning may also occur
offshore in the Gulf Stream/Slope Water frontal zone,
where paralarvae have been collected (O’Dor and Balch
1985; Rowell et al. 1985a), or south of Cape Hatteras
during winter where Illex sp. hatchlings have been
collected (Dawe and Beck 1985). Previous reports of
mated females consist of three individuals that were
caught south of Georges Bank (Dawe and Drew 1981).

DIET
Trophic relationships between I. illecebrosus and
other marine species are described by Dawe and
Brodziak (1998). Northern shortfin squid feed primarily
on fish and crustaceans, but cannibalism of small
individuals (most likely males) by larger females also
occurs, particularly during autumn (Squires 1957;
Froerman 1984; Maurer and Bowman 1985; Dawe
1988). An ontogenetic shift in diet from a
predominance of crustaceans to a predominance of fish
and squid is evident in squid from both stock
components (Maurer and Bowman 1985; Dawe 1988).
Fish prey consists of the early life history stages of
Atlantic cod, Arctic cod and redfish (Squires 1957,
Dawe et al. 1997), sand lance (Dawe et al. 1997),
mackerel and Atlantic herring (O’Dor et al. 1980a;
Dawe et al. 1997), and haddock and sculpin (Squires
1957). Illex also feed on adult capelin (Squires 1957;
O’Dor et al. 1980a; Dawe et al. 1997) and longfin
inshore squid, Loligo pealeii (Vinogradov 1984).
Illex exhibit diel vertical migrations (Roper and
Young 1975; Brodziak and Hendrickson 1999) and
both juveniles (Arkhipkin and Fedulov 1986) and adults
feed primarily at night in the upper layers of the water
column (Maurer and Bowman 1985). On the U.S. shelf
in the spring, I. illecebrosus primarily consume
euphausiids, whereas fish and squid were the dominant
prey in the summer and fall. I. illecebrosus 6-10 cm and
26-30 cm in size eat mostly squid, while 11-15 cm Illex
eat mostly crustaceans and fish, and individuals 16-20
cm eat mostly crustaceans (Maurer and Bowman 1985).
Illex gut content data collected during Northeast
Fisheries Science Center (NEFSC) bottom trawl
surveys (Link and Almeida 2000) were combined
across seasons to compute the percent composition of
major prey categories (Figure 4). For both pre-recruits
(92%) and recruits (57%), a majority of the gut contents
consisted of well-digested prey. Pre-recruit prey types
that could be identified consisted of crustaceans (3%)
and fish (3%). The diet of recruits consisted of
cephalopods (30%), crustaceans (including euphausiids,
7%), and fish (6%).
PREDATION AND MORTALITY
Numerous species of pelagic and benthic fishes
prey on Illex, including bluefin tuna (Butler 1971),
silver hake and red hake (Vinogradov 1972). Other fish
predators include bluefish (Maurer 1975; Buckel 1997),
goosefish (Maurer 1975; Langton and Bowman 1977),
fourspot flounder (Langton and Bowman 1977),
Atlantic cod (Lilly and Osborne 1984), sea raven
(Maurer 1975), spiny dogfish (Templeman 1944;
Maurer 1975), and swordfish (Langton and Bowman
1977; Stillwell and Kohler 1985; Scott and Scott 1988).
Mammalian predators include pilot whales (Squires
1957; Wigley 1982) and the common dolphin (Major
1986). Seabird predators include shearwaters, gannets,
and fulmars (Brown et al. 1981). Northern shortfin
squid are known to exhibit a variety of defense
mechanisms that may reduce predation, such as
camouflage coloration (O’Dor 1983), schooling
behavior, jetting, and ink release (Major 1986).
MIGRATION
Northern shortfin squid are highly migratory. An
individual tagged off Newfoundland was recaptured off
the coast of Maryland, more than 1,000 miles away
(Dawe et al. 1981b). A hypothetical, annual migration
route (Figure 2, from Black et al. 1987) has been
constructed based on seasonal squid distribution
patterns observed in bottom trawl surveys of the U.S.
and Canadian continental shelves, concentrations of
hatchlings in offshore waters south of Cape Hatteras
during winter (Dawe and Beck 1985; Hatanaka et al.
1985; Rowell et al. 1985a), and suggestions that the
neutrally-buoyant egg masses and paralarvae are
rapidly transported northeastward by the Gulf Stream
current (Trites 1983).
Seasonal distribution patterns in Illex abundance
suggest that annual migrations off the U.S. shelf in
autumn and onto the shelf in spring occur
simultaneously along the entire length of the shelf edge
rather than over the shelf in a gauntlet pattern
(Hendrickson 2004; also see Geographical Distribution
below). Tagging studies have demonstrated a
southeastward migration of individuals from
Newfoundland during autumn (Dawe et al. 1981b).
However, the migration patterns between northern and
southern stock components remain unknown and the
offshore fraction of the population is not well
understood because NEFSC surveys do not extend
beyond the edge of the continental shelf and few
stations are sampled in the deepest survey strata (185 to
366 m).
GEOGRAPHICAL DISTRIBUTION
Illex illecebrosus utilizes oceanic and neritic
habitats and adults are believed to undergo long-
distance migrations between boreal, temperate and sub-
tropical waters. Data from U.S. and Canadian seasonal
bottom trawl surveys (1975 to 1994) indicate that
northern shortfin squid are distributed on the
continental shelf of the U.S. and Canada, between
Newfoundland and Cape Hatteras, North Carolina
(Figure 5). The species is present in the Gulf of St.

Lawrence, along the western edge of the Grand Bank,
and along the western shore of Newfoundland, but are
most abundant on the U.S. and Scotian Shelf.
Paralarvae and juveniles inhabit the Gulf Stream-slope
water interface, located off the continental shelf of the
U.S. and Canada, and juveniles also occur on the U.S.
continental shelf. Adults have primarily been collected
on the shelf due to sampling depth limitations of U.S.
and Canadian bottom trawl surveys.
The southernmost limit of the range of I.
illecebrosus is difficult to identify b
ecause of its co-
occurrence with I. coindetii and I. oxygonius.
Distinguishing between the three species is difficult
given the high degree of interspecific and intraspecific
variability in morphological characters (Roper and
Mangold 1998; Roper et al. 1998).
EGGS AND PARALARVAE
Egg masses have never been collected in nature
(O’Dor and Dawe 1998). Paralarvae have been
collected during all seasons (Roper and Lu 1979), but
predominately during January and February in the
nutrient-rich waters of the Slope Water-Gulf Stream
frontal zone, from south of Cape Hatteras to as far north
as the Grand Bank (Dawe and Beck 1985; Hatanaka et
al. 1985). The Gulf Stream has been hypothesized as
the primary mechanism for the transport of egg
balloons and paralarvae toward the Grand Bank (Trites
1983) based on its northeastern trajectory and rapid
current (about 100 km/day).
PRE-RECRUITS
NEFSC bottom trawl surveys [see Reid et al.
(1999) for details] have captured pre-recruits during all
seasons (Figure 6; note that winter and summer
distributions are presented as presence/absence data,
precluding a discussion of abundances). In winter, the
occurrence of pre-recruits is very low and distributed
along the shelf edge between Cape Hatteras and
Georges Bank. In the spring, pre-recruits are
concentrated in low densities along the shelf edge,
including the southern Scotian Shelf; the highest
densities are found off of Cape Hatteras. By summer,
pre-recruits have migrated onto the continental shelf
and are distributed throughout all depths, primarily in
the Mid-Atlantic Bight and along the coast of Maine. In
autumn, pre-recruits begin their return migration to
waters off the shelf. During fall, pre-recruits are present
at depths greater than 60 m, between Georges Bank and
Cape Hatteras, and are most abundant along the shelf
edge. Low densities are also present in the Gulf of
Maine.
The autumn distribution and abundance of pre-
recruits around coastal Massachusetts, based on
Massachusetts inshore bottom trawl surveys [see Reid
et al. (1999) for details], is shown in Figure 7. During
all of the spring surveys conducted between 1978 and
2003, only 16 individuals were collected at five stations
in Massachusetts coastal waters. During the fall
surveys, pre-recruits were present at very low densities
at 28 stations located primarily off Cape Ann and
northern Cape Cod Bay (at depths of 20 to 60 m); a few
higher concentrations were found east of Cape Cod and
near Nantucket Island.
Few (N=30) northern shortfin squid were caught
during seasonal surveys of Narragansett Bay between
1990 and 1996. Illex were captured only during the
summer and at three stations. Individuals ranged in size
from 4 to 11 cm ML.
ADULTS
NEFSC bottom trawl surveys indicate similar
seasonal distributions of recruits and pre-recruits. (See
Figure 8 for recruits; again note that winter and summer
distributions are presented as presence/absence data,
precluding a discussion of abundances). Recruit
abundance during spring and autumn appears to be
greater than that of pre-recruits, but this is partially due
to differences in catchability between the two size
groups. The occurrence of recruits on the U.S.
continental shelf is lowest during winter and
concentrated along the shelf edge (at depths around 366
m) between Georges Bank and Cape Hatteras. By
spring, recruits are still only present at low densities
and concentrated near the shelf edge, extending to south
of Cape Hatteras, where some of the highest densities
are found. Recruits occur both inshore and throughout
the continental shelf during the summer between the
Gulf of Maine and Cape Hatteras. During autumn,
recruits begin to migrate back offshore and south, as
indicated by their high concentrations at depths
between 60 and 366 m.
Recruit abundance was low in Massachusetts
coastal waters during 1978-2003, particularly during
the spring, when only a few recruits were collected at
four stations. During the fall, recruits were collected at
more stations and at higher densities. Abundance was
highest in the waters off Cape Ann and the northern
portion of Cape Cod Bay (Figure 9).
HABITAT CHARACTERISTICS
Habitat characteristics of northern shortfin squid
are summarized by life history stage in Table 1.

EGGS AND PARALARVAE
Based on lab studies, egg balloons probably occur
at water temperatures between 12.5°C, the minimum
temperature required for successful embryonic
development (O’Dor et al. 1982b), and 26°C (Balch et
al. 1985). Egg masses are neutrally-buoyant and
probably occur in midwater near the pycnocline (O’Dor
and Balch 1985).
Illex sp. paralarvae have been collected at water
temperatures from 5 to 20°C (Vecchione 1979; O’Dor
1983; Dawe and Beck 1985; Hatanaka et al. 1985;
Vecchione and Roper 1986), with maximum
abundance, in the Gulf Stream, at temperatures greater
than 16.5°C (Hatanaka et al. 1985) and salinities
ranging from 35 to 37 ppt (Vecchione 1979; O’Dor
1983; Dawe and Beck 1985; Vecchione and Roper
1986). Paralarvae exhibit diel vertical migrations and
are more abundant in the upper layer of the water at
night and in deeper water during the day (Hatanaka et
al. 1985).
JUVENILES
During the spring, epipelagic juveniles migrate
from oceanic to neritic waters as they grow. Juveniles
have been collected from continental slope waters at
temperatures from 14.3 to 16.3°C (Fedulov and
Froerman 1980; Perez 1994), at temperatures above
16°C in the Gulf Stream (Perez 1994), and at
temperatures from 5 to 6°C on the Scotian Shelf in
spring (Perez 1994). During late May, juveniles (34 to
68 mm ML) were collected along the southeast flank of
Georges Bank, at depths of 140 to 260 m, where surface
and bottom temperatures were 10.6°C and 9.9°C,
respectively (Hendrickson 2004). Juveniles have been
collected at salinities of 34 to 37 ppt (Vecchione 1979;
Amaratunga et al. 1980b; Fedulov and Froerman 1980;
Rowell et al. 1985a). South of Cape Hatteras, squid 7
to 10 cm ML are most abundant during spring
(Whitaker 1980).
Distributions of pre-recruits relative to bottom
water temperature, depth, and salinity based on spring
and fall NEFSC bottom trawl surveys from the Gulf of
Maine to Cape Hatteras are shown in Figure 10. During
the spring surveys, pre-recruits occur in deep water and
are most abundant at depths ranging from 101 to 300 m,
bottom temperatures of 11 to 14ºC and at salinities of
35 to 36 ppt. During the fall surveys, pre-recruits occur
in greater abundance across a broader depth range, and
in a wider range of temperatures and salinities. During
autumn, juveniles are most abundant at bottom
temperatures of 10 to 13ºC and salinities of 32 to 35
ppt.
The spring and autumn distributions of pre-recruits
in Massachusetts coastal waters relative to bottom
water temperature and depth based on Massachusetts
inshore bottom trawl surveys are shown in Figure 11.
As observed in the NEFSC spring surveys, pre-recruits
are distributed offshore during spring; only 16
individuals were collected at five stations in
Massachusetts coastal waters (< 80 m deep), most at
temperatures of 11ºC and at a depth of 1
1 to 15 m.
During the fall, pre-recruits were present at very low
densities at only 28 stations and were most abundant at
depths of 31 to 55 m, and were found over at bottom
temperatures of 6 to 10ºC.
ADULTS
Adults have been captured at temperatures ranging
from -0.5 to 27.3°C (Whitaker 1980), salinities of 30 to
36.5 ppt (Palmer and O’Dor 1978), and at depths
ranging from the surface to 1000 m or more (Whitaker
1980), depending on the time of year (see Migrations
above). In summer, on the eastern U.S. continental
shelf, adults are most abundant at depths of 100 to 200
m (Bowman 1977; Grinkov and Rikhter 1981) and are
not generally found in waters shallower than 18 m. In
the fall and winter, adults migrate offshore, and have
been found at 100 to 945 m (Amaratunga et al. 1980a;
Felley and Vecchione 1995). However, there is little
information on the offshore component of the
population, which may be found at depths greater than
1000 m (O’Dor and Dawe 1998).
Distributions of recruits relative to bottom water
temperature, depth, and salinity based on NEFSC
spring and fall bottom trawl surveys are shown in
Figure 12. During the spring, recruits are found over a
temperature range of 4 to 20°C, but are most abundant
at 10 to 14°C. Recruits are found over a depth range of
11 to 500 m, but are most abundant at 121 to 400 m.
The majority of recruits occur at a salinity of 35 ppt in
the spring. In the autumn, recruits were found over a
bottom temperature range of 4 to about 21°C, and are
most abundant at 8 to 13°C. Recruit abundance
increased with depth between 31 and 140 m and
reached a secondary peak at 201 to 300 m. During
autumn, recruits occur over a salinity range from 31 to
36 ppt.
The spring and autumn distributions of recruits in
Massachusetts coastal waters relative to bottom water
temperature and depth based on Massachusetts inshore
bottom trawl surveys are shown in Figure 13. The few
adults caught in the spring occurred at temperatures of
10 to 13°C and at depths of 11 to 15 m, 26 to 30 m, and
41 to 45 m. Recruits were caught at higher densities in
the fall and were found over a temperature range of 4 to
15°C, with most recruits found between 7 and 9°C.

Recruits were caught over a depth range of 11 to 85 m,
with most found between 41 and 75 m.
RESEARCH NEEDS
Additional research is needed to better understand
the life cycle of this species. In particular, recruitment
patterns and the exchange of squid between the
northern and southern stock components remain
unknown, along with the migration routes from fishing
areas during autumn. U.S. research surveys do not
include waters deeper than 366 m, so it remains
unknown what fraction of the stock resides offshore and
whether spawning occurs there. In addition, the
location of the winter spawning area has not been
confirmed.
ACKNOWLEDGMENTS
The authors thanks Jason Link for summarizing
data from the NEFSC food habits database and Jackie
Riley and Claire Steimle for library assistance. We are
also grateful to John McCarthy for preparing the
histogram graphs and to David Packer for his editorial
comments and organization of the document.
REFERENCES CITED
Amaratunga, T. 1980a. Growth and maturation patterns
of short-finned squid (Illex illecebrosus) on the
Scotian Shelf. Northwest Atl. Fish. Organ. (NAFO)
Sci. Counc. Res. Doc. No. 80/II/39. 17 p.
Amaratunga, T. 1980b. Preliminary estimates of
predation by the short-finned squid (Illex
illecebrosus) on the Scotian Shelf. Northwest Atl.
Fish. Organ. (NAFO) Sci. Counc. Res. Doc. No.
80/II/31. 13 p.
Amaratunga, T.M. 1983. The role of cephalopods in the
marine ecosystem. In: Caddy, J.F., editor.
Advances in assessment of world cephalopod
resources. FAO Fish. Tech. Pap. 231. Food and
Agriculture Organization of the United Nations,
Rome, Italy. p. 379-415.
Amaratunga, T. and I.H. McQuinn. 1979. Abundance
estimation of Illex illecebrosus during the joint
Canada-Japan selectivity research program on the
Scotian Shelf in 1978. Int. Comm. Northwest Atl.
Fish. (ICNAF) Res. Doc. 79/II/36. 12 p.
Amaratunga, T., M. Roberge, and L. Wood. 1978. An
outline of the fishery and biology of the short-
finned squid, Illex illecebrosus, in eastern Canada.
In: Balch, N., Amaratunga, T., O’Dor, R.K.,
editors. Proceedings of a workshop on the squid,
Illex illecebrosus. Dalhousie Univ., Halifax, Nova
Scotia, May, 1978; and a bibliography on the genus
Illex. Can. Fish. Mar. Serv. Tech. Rep. no. 833.
Fisheries and Marine Service, Halifax, Nova
Scotia. p. 2.1-2.5.
Amaratunga, T., M. Roberge, J. Young, and Y.
Uozumi. 1980a. Summary of joint Canada/Japan
research program on short-finned squid (Illex
illecebrosus), 23 October to 29 November 1979:
emigration and biology. Northwest Atl. Fish.
Organ. (NAFO) Sci. Counc. Res. Doc. 80/II/40. 20
p.
Amaratunga, T., T. Rowell, and M. Roberge. 1980b.
Summary of joint Canada/U.S.S.R. research
program on short-finned squid (Illex illecebrosus),
16 February to 4 June, 1979: Spawning stock and
larval survey. Northwest Atl. Fish. Organ. (NAFO)
Sci. Counc. Res. Doc. No. 80/II/38. 36 p.
Arkhipkin, A.I. and P.P. Fedulov. 1986. Diel
movements of juvenile Illex illecebrosus and other
cephalopods in the shelf water-slope water frontal
zone off the Scotian Shelf in spring. J. Northwest
Atl. Fish. Sci. 7: 15-24.
Balch, N., R.K. O’Dor, and P. Helm. 1985. Laboratory
rearing of rhynchoteuthions of the ommastrephid
squid Illex illecebrosus (Mollusca: Cephalopoda).
In: Mangold, K.M., Boletzky S.V., editors. Biology
and distribution of early juvenile cephalopods.
(Biologie et distribution de cephalopodes juveniles
precoces.) Vie Milieu 35. p. 243-246.
Bennett, B.A. 1978. Underwater observations of the
squid Illex illecebrosus in the Newfoundland
inshore waters. In: Balch, N., Amaratunga, T.,
O’Dor, R.K., editors. Proceedings of a workshop
on the squid, Illex illecebrosus. Dalhousie Univ.,
Halifax, Nova Scotia, May, 1978; and a
bibliography on the genus Illex. Can. Fish. Mar.
Serv. Tech. Rep. No. 833. Fisheries and Marine
Service, Halifax, Nova Scotia. p. 12.1-12.9.
Black, G.A.P., T.W. Rowell, and E.G. Dawe. 1987.
Atlas of the biology and distribution of the squids
Illex illecebrosus and Loligo pealei in the
northwest A
tlantic. Can. Spec. Publ. Fish. Aquat.
Sci. 100. 62 p.
Bowman, M.J. 1977. Hydrographic properties. Marine
Ecosystems Analysis (MESA) Program, MESA
New York Bight Project. N.Y. Sea Grant Institute,
Albany, NY. 78 p.
Brodziak, J.K.T. and L.C. Hendrickson. 1999. An
analysis of environmental effects on survey catches
of squids Loligo pealei and Illex illecebrosus in the
northwest Atlantic. Fish. Bull. (U.S.) 97: 9-24.

Brown, R.G. B., S.P. Barker, D.E. Gaskin, and M.R.
Sandeman. 1981. The foods of great and sooty
shearwaters, Puffinus gravis and P. griseus, in
eastern Canadian waters. Ibis 123: 19-30.
Buckel, J.A. 1997. Impact of bluefish (Pomatomus
saltatrix) predation on estuarine and continental
shelf fishes. Ph.D. dissertation, State Univ. of New
York, Stony Brook, NY. 199 p.
Butler, M. 1971. Biological investigation of aspects of
the life history of bluefin tuna, 1970-71.
Newfoundland Lab. Tour. Develop. Off., St.
John’s, Newfoundland. 169 p.
Caddy, J.F. 1991. Daily rings on squid statoliths: an
opportunity to test standard population models? In:
Jereb, P., Ragonese, S., von Boletzky, S., editors.
Squid age determination using statoliths.
Proceedings of an international workshop, 9-14
October 1989, Instituto di Tecnologia della Pesca e
del Pescato, Mazara del Vallo, Italy. Instituto di
Tecnologia della Pesca e del Pescato Special
Publication No. 1. p. 53-66.
Cargnelli, L.M., S.J. Griesbach, and C.A. Zetlin. 1999.
Essential fish habitat source document: Northern
shortfin squid, Illex illecebrosus, life history and
habitat characteristics. NOAA Tech. Mem. NMFS-
NE-147.
Coelho, M.L. 1985. Review of the influence of
oceanographic factors on cephalopod distribution
and life cycles. Northwest Atl. Fish. Organ.
(NAFO) Sci. Counc. Stud. 9: 47-57.
Coelho, M.L. and R.K. O’Dor. 1993. Maturation,
spawning patterns, and mean size at maturity in the
short-finned squid Illex illecebrosus. In: Okutani,
T., O’Dor, R.K., Kubodera, T. editors. Recent
advances in cephalopod fisheries biology. Tokyo:
Tokai Univ. Press. p. 81-91.
Csanady, G.T. and P. Hamilton. 1988. Circulation of
slope water. Continent. Shelf Res. 8 (5-7): 565-
624.
Dawe, E.G. 1988. Length-weight relationships for
short-finned squid in Newfoundland and the effect
of diet on condition and growth. Trans. Am. Fish.
Soc. 177: 591-599.
Dawe, E.G. and P.C. Beck. 1985. Distribution and size
of short-finned squid (Illex illecebrosus) larvae in
the northwest Atlantic from winter surveys in
1969, 1981, and 1982. J. Northwest Atl. Fish. Sci.
6 (1): 43-55.
Dawe, E.G. and P.C. Beck. 1997. Population structure,
growth, and sexual maturation of short-finned
squid (Illex illecebrosus) at Newfoundland. Can. J.
Fish. Aquat. Sci. 54: 137-146.
Dawe, E.G., P.C. Beck, and H.J. Drew. 1981a.
Distribution and biological characteristics of young
short-finned squid (Illex illecebrosus) in the
northwest Atlantic, February 20-March 11, 1981.
Northwest Atl. Fish. Organ. (NAFO) Sci. Counc.
Res. Doc. 81/VI/26. 9 p.
Dawe, E.G., P.C. Beck, H.J. Drew, and G.H. Winters.
1981b. Long-distance migration of a short-finned
squid, Illex illecebrosus. J. Northwest Atl. Fish.
Sci. 2: 75-76.
Dawe, E.G. and J. Brodziak. 1998. Trophic
relationships, ecosystem variability, and
recruitment. In: Rodhouse, P.G., Dawe, E.G.,
O’Dor, R.K., editors. Squid recruitment dynamics:
the genus Illex as a model, the commercial Illex
species and influences on variability. FAO Fish.
Tech. Pap. No. 376. Food and Agriculture
Organization of the United Nations, Rome, Italy. p.
125-156.
Dawe, E.G., E.L. Dalley, and W.W. Lidster. 1997. Fish
prey spectrum of short-finned squid (Illex
illecebrosus) at Newfoundland. Can. J. Fish.
Aquat. Sci. 54 (Suppl. 1): 200-208.
Dawe, E.G. and H.J. Drew. 1981. Record of a mature
female short-finned squid, Illex illecebrosus,
captured inshore at Newfoundland and previous
captures of mature females in the northwest
Atlantic. J. Northwest Atl. Fish. Sci. 2: 61-65.
Dawe, E.G. and L.C. Hendrickson. 1998. A review of
the biology, population dynamics, and exploitation
of short-finned squid in the northwest Atlantic
Ocean, in relation to assessment and management
of the resource. Northwest Atl. Fish. Organ.
(NAFO) Sci. Counc. Res. Doc. 98/59. 33 p.
Dawe, E.G., R.K. O’Dor, P.H. Odense, and G.V.
Hurley. 1985. Validation and application of an
ageing technique for short-finned squid (Illex
illecebrosus). J. Northwest Atl. Fish. Sci. 6: 107-
116.
DeMont, M.E. 1981. The effects of activity,
temperature, and mass on the metabolism of the
squid, Illex illecebrosus. M.S. thesis, Dalhousie
Univ., Halifax, Nova Scotia.
Durward, R.D., T. Amaratunga, and R.K. O’Dor. 1978.
Maturation index and fecundity for female squid,
Illex illecebrosus In: Balch, N., Amaratunga, T.,
O’Dor, R.K,. editors. Proceedings of a workshop
on the squid Illex illecebrosus. Dalhousie Univ.,
Serv. Tech. Rep. no. 833. Fisheries and Marine
Durward, R.D., E. Vessey, R.K. O’Dor, and T.
Amaratunga. 1980. Reproduction in the squid, Illex
illecebrosus: first observations in captivity and
implications for the life cycle. Int. Comm.
Northwest Atl. Fish. (ICNAF) Sel. Pap. 6: 7-13.
Ennis, G.P. and P.W. Collins. 1979. Food and feeding
of the short-finned squid, Illex illecebrosus, during
its seasonal occurrence in the Newfoundland area.
Int. Comm. Northwest Atl. Fish. (ICNAF) Sel.
Pap., No. 5: 25-29.

Fedulov, P.P. and Yu. M. Froerman. 1980. Effect of
abiotic factors on distribution of young shortfin
squids, Illex illecebrosus (LeSueur, 1821).
Res. Doc. 80/VI/98. 22 p.
Felley, J.D. and M. Vecchione. 1995. Assessing habitat
use by nekton on the continental slope using
archived videotapes from submersibles. Fish. Bull.
(U.S.) 93: 262-273.
Froerman, Y.M. 1979. Biomass estimates of the short-
finned squid, Illex illecebrosus, in ICNAF Division
4W, 1978. Int. Comm. Northwest Atl. Fish.
(ICNAF) Res. Doc. 79/II/28. 9 p.
Froerman, Y.M. 1984. Feeding spectrum and trophic
relationships of short-finned squid (Illex
illecebrosus) in the Northwest Atlantic. Northwest
Atl. Fish. Organ. NAFO Sci. Counc. Stud. 7:67-75.
Frost, N. and H. Thompson. 1933. The squids. Ann.
Rep. Newfoundland Fish. Res. Comm. 2(1): 80-86.
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.
Grinkov, Y.A. and V.A. Rikhter. 1981. Some data on
distribution of groundfish and short-finned squid
along the oceanic slopes of the Scotian Shelf in
spring 1979. Northwest Atl. Fish. Organ. (NAFO)
Sci. Counc. Res Doc. 81/VI/63. 13 p.
Hatanaka, H. 1986. Body size of short-finned squid
Illex illecebrosus larvae in the northwest Atlantic.
Bull. Jap. Soc. Sci. Fish./Nissuishi. 52 (1): 19-22.
Hatanaka, H., A.M.T. Lange, and T. Amaratunga. 1985.
Geographical and vertical distribution of short-
finned squid (Illex illecebrosus) larvae in the
northwest Atlantic. Northwest Atl. Fish. Organ.
(NAFO) Sci. Counc. Stud. 9: 93-99.
Hendrickson, L. 1998. Northern shortfin squid. In:
Clark, S.H., editor. Status of the fishery resources
off the northeastern United States for 1998. NOAA
Tech. Mem. NMFS-NE-115. p. 116-117.
Hendrickson, L.C. 2004. Population biology of northern
shortfin squid (Illex illecebrosus) in the northwest
Atlantic Ocean and initial documentation of a
spawning area. ICES J. Mar. Sci. 61(2): 252-266.
Hendrickson, L.C., J. Brodziak, M. Basson, and P.
Rago. 1996. Stock assessment of northern shortfin
squid in the northwest Atlantic during 1993.
Northeast Fish. Sci. Cent. Ref. Doc. 96-05g. 63 p.
Hendrickson, L.C., E.G. Dawe, and M. A. Showell.
2002. Assessment of northern shortfin squid (Illex
illecebrosus) in Subareas 3+4 for 2001. Northwest
Atl. Fish. Organ. (NAFO) Sci. Counc. Res. Doc.
02/56, Ser. No. N4668. 17 p.
Hirtle, R. W.M. 1978. Observations on feeding and
grooming behaviors of captive squid, Illex
illecebrosus (Lesueur, 1821). In: Balch, N.,
Amaratunga, T., O’Dor, R.K., editors. Proceedings
of a workshop on the squid, Illex illecebrosus.
Dalhousie Univ., Halifax, Nova Scotia, May, 1978;
and a bibliography on the genus Illex. Can. Fish.
Mar. Serv. Tech. Rep. 833. Fisheries and Marine
Service, Halifax, Nova Scotia. p.13.1-13.5.
Hirtle, R. W.M., M.E. DeMont, and R.K. O’Dor. 1981.
Feeding, growth, and metabolic rates in captive
short-finned squid, Illex illecebrosus, in relation to
the natural population. J. Shellfish Res. 1(2): 187-
192.
Hurley, G.V. 1980. Recent developments in the squid,
Illex illecebrosus, fishery of Newfoundland,
Canada. Mar. Fish. Rev. 42 (7-8): 15-22.
Hurley, G.V., P.H. Odense, R.K. O'Dor, and E.G.
Dawe. 1985. Strontium labeling for verifying daily
growth increments in the statoliths of the short-
finned squid (Illex illecebrosus). Can. J. Fish.
Aquat. Sci. 42: 380-383.
Jackson, G.D. 1994. Application and future potential of
statolith increment analysis in squid and sepioids,
Can. J. Fish. Aquat. Sci. 51: 2612-2625.
Lange, A.M.T. 1978. Historical trends and current
status of the squid fisheries off the northeastern
United States. In: Balch, N., Amaratunga, T.,
O’Dor, R.K., editors. Proceedings of a workshop
on the squid, Illex illecebrosus. Dalhousie Univ.,
Serv. Tech. Rep. 833. Fisheries and Marine
Lange, A.M.T. and K.L. Johnson. 1981. Dorsal mantle
length - total weight relationships of squids Loligo
pealei and Illex illecebrosus from the Atlantic coast
of the United States. NOAA Tech. Rep. NMFS
SSRF-745. 17 p.
Lange, A.M.T. and M.P. Sissenwine. 1980. Biological
considerations relevant to the management of squid
(Loligo pealei and Illex illecebrosus) of the
northwest Atlantic. Mar. Fish. Rev. 42 (7-8): 23-
38.
Langton, R.W. and R.E. Bowman. 1977. An abridged
account of predator-prey interactions for some
northwest Atlantic species of fish and squid. U.S.
Natl. Mar. Fish. Serv., Northeast Fish. Cent., Lab.
Ref. Doc. No 77-17.
Laptikhovsky, V.V. and C.M. Nigmatullin. 1993. Egg
size, fecundity, and spawning in females of the
genus Illex (Cephalopoda: Ommastrephidae). ICES
J. Mar. Sci. 50: 393-403.
Lilly, G.R. and D.R. Osborne. 1984. Predation by
Atlantic cod (Gadus morhua) on short-finned squid
(Illex illecebrosus) off eastern Newfoundland and
in the northeastern Gulf of St. Lawrence.
Res. Doc. 84/108. 16 p.

Link, J.S. and Almeida, F.P. 2000. An overview and
history of the food web dynamics program of the
Northeast Fisheries Science Center, Woods Hole,
Massachusetts. NOAA Tech. Memo. NMFS-NE-
159.
Lux, F.E., J.R. Uzmann, and H.F. Lind. 1978.
Strandings of shortfin squid, Illex illecebrosus, in
New England in fall 1976. Mar. Fish. Rev. 40(1):
21-26.
[MAFMC] Mid-Atlantic Fishery Management Council.
1998. Amendment 8 to the Atlantic mackerel,
squid, and butterfish fishery management plan.
MAFMC. [Dover, DE.] 351 p. + appendices.
Major, P.F. 1986. Notes on a predator-prey interaction
between common dolphins (Delphinus delphis) and
short-finned squid (Illex illecebrosus) in Lydonia
Submarine Canyon, western North Atlantic Ocean.
J. Mamm. 67 (4): 769-770.
Mann, K.H. and J.R.N. Lazier. 1991. Dynamics of
marine ecosystems. Biological-physical
interactions in the oceans. Blackwell Scientific
Publications, Boston, MA. 466 p.
Maurer, R. 1975. A preliminary description of some
important feeding relationships. Int. Comm.
Northwest Atl. Fish. (ICNAF) Res. Doc. No.
76/IX/130.
Maurer, R.O. and R.E. Bowman. 1985. Food
consumption of squids (Illex illecebrosus and
Loligo pealei) off the northeastern United States.
Stud. 9: 117-124.
McLellan, H.J., L. Lauzier, and W.B. Bailey. 1953. The
slope water off the Scotian Shelf. J. Fish. Res.
Board Can. 10: 155-176.
Mercer, M.C. 1973a. Distribution and biological
characteristics of the ommastrephid squid, Illex
illecebrosus illecebrosus (LeSueur) in the
Newfoundland area. Fish. Res. Board Can.
Manuscr. Rep. Ser. (Biol.) 834. 36 p.
Mercer, M.C. 1973b. Sexual maturity and sex ratios of
the ommastrephid squid, Illex illecebrosus
(LeSueur), at Newfoundland (Subarea 3). Int.
Comm. Northwest Atl. Fish. (ICNAF) Res. Doc.,
No. 73/71. 14 p.
Mercer, M.C. and G. Paulmier. 1974. Distribution and
biological characteristics of the short-finned squid
(Illex illecebrosus) on the continental shelf of
Subareas 3 and 4 in May-June, 1973. Int. Comm.
Northwest Atl. Fish. (ICNAF) Res. Doc. 74/87. 11
p.
Mesnil, B. 1977. Growth and life cycle of squid, Loligo
pealei and Illex illecebrosus, from the Northwest
Atlantic. Int. Comm. Northwest Atl. Fish. (ICNAF)
Sel. Pap. No. 2: 55-69.
Nicol, S. and R.K. O’Dor. 1985. Predatory behavior of
squid (Illex illecebrosus) feeding on surface
swarms of euphausiids. Can. J. Zool. 63: 15-17.
Nigmatullin, C. 1987. Ecological niche of the oceanic
squids of the family Ommastrephidae: Ontogenetic
and evolutionary aspects. In Molluscs: results and
perspectives of their investigations, VIII. All-
Union Symposium on Molluscan Study, 7-9 April.
p. 92-94. Nauka Press, Leningrad.
O’Dor, R.K. 1983. Illex illecebrosus. In: Boyle, P.R,.
editor. Cephalopod life cycles, Vol. I, Species
accounts. London: Academic Press. p. 175-199.
O’Dor, R.K. and N. Balch. 1985. Properties of Illex
illecebrosus egg masses potentially influencing
larval oceanographic distribution. Northwest Atl.
Fish. Organ. (NAFO) Sci. Counc. Stud. 9: 69-76.
O’Dor, R.K., N. Balch, and T. Amaratunga. 1982a.
Laboratory observations of midwater spawning by
Illex illecebrosus. Northwest Atl. Fish. Organ
(NAFO) Sci. Counc. Res. Doc. No. 82/VI/5. 8 p.
O’Dor, R.K., N. Balch, E.A. Foy, R. W. M. Hirtle, D.A.
Johnston, and T. Amaratunga. 1982b. Embryonic
development of the squid, Illex illecebrosus, and
effect of temperature on developmental rates. J.
Northwest Atl. Fish. Sci. 3: 41-45.
O’Dor, R.K. and E.G. Dawe. 1998. Illex illecebrosus.
In: Rodhouse, P.G., Dawe, E.G., O’Dor, R.K.,
editors. Squid recruitment dynamics: the genus
Illex as a model, the commercial Illex species and
influences on variability. FAO Fish. Tech. Pap. No.
376. Food and Agriculture Organization of the
United Nations, Rome, Italy. p. 77-104.
O’Dor, R.K. and R.D. Durward. 1979. A preliminary
note on Illex illecebrosus larvae hatched from eggs
spawned in captivity. Proc. Biol. Soc. Wash. 91
(4): 1076-1078.
O’Dor, R.K., R.D. Durward, D.B. Steadman, and N.
Balch. 1977. Laboratory studies on the life cycle
and vertical migration of the squid Illex
illecebrosus. ICES C.M. 1977/R: 9.
O’Dor, R.K., R. D. Durward, E. Vessey, and T.
Amaratunga. 1980a. Feeding and growth in captive
squid, Illex illecebrosus, and the influence of food
availability on growth in the natural population.
Int. Comm. Northwest Atl. Fish (ICNAF) Sel. Pap.
No. 6: 15-21.
O’Dor, R.K., P.L. Foy, P.L. Helm, and N. Balch. 1986.
The locomotion and energetics of hatchling squid,
Illex illecebrosus. Am. Malacol. Bull. 4: 55-60.
O’Dor, R.K., E. Vessey, and T. Amaratunga. 1980b.
Factors affecting fecundity and larval distribution
in the squid, Illex illecebrosus. Northwest Atl. Fish.
Organ (NAFO) Sci. Counc. Res. Doc. 80/II/39. 9 p.

Palmer, B.W. and R.K. O’Dor. 1978. Changes in
vertical migration patterns of captive Illex
illecebrosus in varying light regimes and salinity
gradients. In: Balch, N., Amaratunga, T., O’Dor,
R.K., editors. Proceedings of the workshop on the
squid, Illex illecebrosus. Dalhousie Univ., Halifax,
Nova Scotia, May, 1978; and a bibliography on the
genus Illex. Can. Fish. Mar. Serv. Tech. Rep. no.
833. Fisheries and Marine Service, Halifax, Nova
Scotia. p. 23.1-23.12.
Perez, J.A.A. 1994. The early life history of the short-
finned squid, Illex illecebrosus (Cephalopoda:
Ommastrephidae), as reconstructed from the
gladius structure. Ph.D. dissertation, Dalhousie
Univ., Halifax, Nova Scotia. 150 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.
Roper, C.F.E. and C.C. Lu. 1979. Rhynchoteuthion
larvae of ommastrephid squids of the western
North Atlantic, with the first description of larvae
and juveniles of Illex illecebrosus. Proc. Biol. Soc.
Wash. 91 (4): 1039-1059.
Roper, C.F.E., C.C. Lu, and M. Vecchione. 1998.
Systematics and distribution of Illex species; a
revision (Cephalopoda, Ommastrephidae).
Smithson. Contrib. Zool. No. 586. 599 p.
Roper, C.F.E. and K. Mangold. 1998. Systematic and
distributional relationships of Illex coindetii to the
genus Illex (Cephalopoda; Ommastrephidae). In:
Rodhouse, P.G., Dawe, E.G., O’Dor, R.K., editors.
Squid recruitment dynamics: the genus Illex as a
model, the commercial Illex species, and influences
on variability. FAO Fish. Tech. Pap. No. 376. Food
and Agriculture Organization of the United
Nations, Rome, Italy. p. 13-26.
Roper, C.F.E., M.J. Sweeney, and C.E. Nauen. 1984.
FAO species catalogue Vol. 3. Cephalopods of the
world. An annotated and illustrated catalogue of
species of interest to fisheries. FAO Fish. Synop.
No. 125 Vol. 3. Food and Agriculture Organization
of the United Nations, Rome, Italy.
Roper, C.F.E. and R.E. Young. 1975. Vertical
distribution of pelagic cephalopods. Smithson.
Contrib. Zool. No. 209. 51 p.
Rowell, T.W. and R.W. Trites. 1985. Distribution of
larval and juvenile Illex (Mollusca, Cephalopoda)
in the Blake Plateau region (northwest Atlantic).
Vie Milieu 35: 139-147.
Rowell, T.W., R.W. Trites, and E.G. Dawe. 1985a.
Distribution of short-finned squid (Illex
illecebrosus) larvae and juveniles in relation to the
Gulf Stream frontal zone between Florida and Cape
Hatteras. Northwest Atl. Fish. Organ. (NAFO) Sci.
Counc. Stud. 9: 77-92.
Rowell, T.W., J.H. Young, J.C. Poulard, and J.P.
Robin. 1985b. Changes in distribution and
biological characteristics of Illex illecebrosus on
the Scotian Shelf, 1980-83. Northwest Atl. Fish.
Organ. (NAFO) Sci. Counc. Stud. 9: 11-26.
Scott, J.S. 1982. Selection of bottom type by
groundfishes of the Scotian Shelf. Can. J. Fish.
Aquat. Sci. 39: 943-947.
Scott, W.B. and M.G. Scott. 1988. Atlantic fishes of
Canada. Can. Bull. Fish. Aquat. Sci. 219. 731 p.
Squires, H.J. 1957. Squid, Illex illecebrosus, in the
Newfoundland fishing area. J. Fish. Res. Board
Can. 14: 693-728.
Squires, H.J. 1966. Feeding habits of the squid Illex
illecebrosus. Nature (London) 211: 1321.
Squires, H.J. 1967. Growth and hypothetical age of the
Newfoundland bait squid, Illex illecebrosus
illecebrosus. J. Fish. Res. Board Can. 24: 1209-
1217.
Stillwell, C.E. and N.E. Kohler. 1985. Food and feeding
ecology of the swordfish Xiphias gladius in the
western North Atlantic with estimates of daily
ration. Mar. Ecol. Prog. Ser. 22: 239-247.
Templeman, W. 1944. The life history of the spiny
dogfish (Squalus acanthias) and the vitamin A
values of dogfish liver oil. Newfoundland Dep.
Nat. Resourc. Bull. Fish. No. 15. 102 p.
Templeman, W. 1966. Marine resources of Newfound-
land. Fish. Res. Board Can. Bull. 154. 170 p.
Trites, R.W. 1983. Physical oceanographic features and
processes relevant to Illex illecebrosus spawning in
the western North Atlantic and subsequent larval
distribution. Northwest Atl. Fish. Organ. (NAFO)
Sci. Counc. Stud. 6: 39-55.
Vecchione, M. 1979. Larval development of Illex
Steenstrup, 1880, in the northwestern Atlantic, with
comments on Illex larval distribution. Proc. Biol.
Soc. Wash. 91(4): 1060-1075.
Vecchione, M. and C.F.E. Roper. 1986. Occurrence of
larval Illex illecebrosus and other young
cephalopods in the Slope Water/Gulf Stream
interface. Proc. Biol. Soc. Wash. 99(4): 703-708.
Vecchione, M., C.F.E. Roper, and M.J. Sweeney. 1989.
Marine flora and fauna of the eastern United States.
Mollusca: Cephalopoda. NOAA Tech. Rep. NMFS
73. 23 p.
Vinogradov, V.I. 1970. Distribution of some
commercial fish species on the USA shelf in the
winter. Ryb. Khoz. No. 12: 10-11.
Vinogradov, V.I. 1972. Studies of the food habits of
silver and red hake in the northwest Atlantic area,
1965-67. Int. Comm. Northwest Atl. Fish.
(ICNAF) Res. Bull. No. 9: 41-50.
Vinogradov, V.I. 1984. On feeding of two squid species
in the northwest Atlantic. Northwest Atl. Fish.
Organ. (NAFO) Sci. Counc. Res. Doc. 84/117. 12
p.

Vinogradov, V.I. and A.S. Noskov. 1979. Feeding of
short-finned squid, Illex illecebrosus, and long-
finned squid, Loligo pealei, off Nova Scotia and
New England, 1974-1975. Int. Comm. Northwest
Atl. Fish. (ICNAF) Sel. Pap. No. 5: 31-36.
Waldron, D.E. 1983. Factors influencing Scotian Shelf
finfish and squid interactions with special reference
to silver hake. Northwest Atl. Fish Organ. (NAFO)
Sci. Counc. Res. Doc. 83/IX/92. 28 p.
Whitaker, J.D. 1980. Squid catches resulting from trawl
surveys off the southeastern United States, M.S.
thesis, College of Charleston, SC. 164 p.
Wigley, R.L. 1982. Short-finned squid, Illex
illecebrosus. In: Grosslein, M.D., Azarovitz, T.R.,
editors. Fish distribution. MESA New York Bight
Atlas Monograph 15. N.Y. Sea Grant Institute,
Albany, NY. p. 135-138.
Young, R.E. and R.F. Harman. 1988. “Larva”,
“paralarva” and “subadult” in cephalopod
terminology. Malacologia 29 (1): 201-207.

Table 1. Summary of life history and habitat parameters for northern shortfin squid Illex illecebrosus.
Life Stage Size and Growth Habitat Substrate Temperature Salinity
Eggs 1
Eggs protected in
gelatinous masses
ranging in diameter
from 30 - 100 cm. In
lab studies, females
produced 10,000 -
400,000 eggs.
Egg masses have not been collected
in the wild. It is hypothesized that
egg masses are transported
northeasterly in the Gulf Stream
current based on distribution of
paralarvae and temperatures required
for hatching.
Egg masses are
pelagic; do not attach
to substrate (based
on lab-induced
spawning events).
Egg incubation lasts 16
days at 13°C, 12 days at
16°C and 8 days at 21°C;
normal development
requires at least 13°C.
Egg masses have
greater density than
seawater; possibly
become neutrally -
buoyant in colder,
higher-density
water (shown in lab
studies).
Paralarvae 2
Hatchling:
1.0-1.1 mm
Paralarvae:
1.2-5.0 mm
Transitional:
5.1-6.9 mm
Size at hatch: 1.0-1.1
mm ML.
Paralarvae have non-
functional tentacles;
body not yet elongated.
Rhynchoteuthion (Type
C1
) larval stage ends
when proboscis splits
into 2 tentacles. Mantle
length increases during
migration from Gulf
Stream to continental
shelf. Only find
hatchlings south of
Cape Hatteras.
Offshore, along continental shelf edge
from surface waters t o 360 m.
Hatching occurs at inshore boundary
of Gulf Stream, 9 to 16 days after
spawning. Paralarvae have been
found during winter and spring off
tail of Grand Bank. Abundant in late
February-March in Gulf Stream/slope
waters above the thermocline. The
convergence of Gulf Stream and slope
water creates an area of high
productivity that is beneficial to
young for feeding and growth.
Undergo diel vertical migrations;
greater abundance during the day at
50-100 m.
Found from
5-20°C; maximum
abundance at
temperatures > 16.5°C.
Found at salinities
ranging from 35-37
ppt.
Pre-
recruits 3
≤ 10.0 cm
Separation of proboscis
into tentacles indicates
onset of juvenile stage.
Larger juveniles found
from east to west,
indicating westward
movement on
continental shelf with
growth. Growth is
approximately 1.5
mm/day.
Winter: in Gulf Stream/slope water
interface.
Spring: begin migration onto U.S.
continental shelf (Georges Bank to
south of Cape Hatteras).
Summer: occur throughout U.S. shelf
(Georges Bank to Cape Hatteras).
Fall: migrate off U.S. shelf (Georges
Bank to south of Cape Hatteras).
Undergo diel vertical migrations;
greater abundance near the bottom
during the day.
Gulf Stream: > 16°C;
slope water: < 16°C;
surface: 14-21°C;
continental shelf: 5-6°C
in spring.
Pre-recruits on U.S. shelf
most abundant at bottom
temperatures > 10°C and
surface temperatures
14.6-20.5°C.
Found at salinities
ranging from 34-37
ppt.
Recruits 4
≥ 11 cm
Can reach size of 35 cm
ML.
Life span less than a
year; (215 days for
squid in U.S. shelf
waters). Males and
females grow about 1
mm/day. Females
generally larger than
males.
Range from Labrador to south of
Cape Hatteras; most abundant at
depths of 100-150m.
Winter: low abundance along edge of
U.S. shelf; presumably in warmer
waters offshore and south of Cape
Hatteras.
Spring: begin migration onto U.S.
shelf (Georges Bank to south of Cape
Hatteras) and Scotian Shelf.
Summer: occur throughout U.S. shelf
(Gulf of Maine to Cape Hatteras),
Scotian Shelf and inshore
Newfoundland waters.
Fall: migrate off continental shelf of
U.S. and Canada; presumably to
spawn.
Increase in squid size with depth in
autumn.
Over various
sediment types,
including sand-silt or
"Sambro sand"
(sediment between
banks and edges of
basins on Scotian
Shelf, as well as
along edge of
continental shelf,
100-300m). Avoid
areas inhabited by
anemones.
Illex ≥ 11 cm found at
bottom temperatures
ranging from 3.5-15.0°C
(surface > 20°C), most
abundant at bottom
temperatures of 5-
10.0°C. Maturation may
be enhanced by high
temperatures but not
initiated by it.
Generally found at
30-36.5 ppt.
1
Durward etal. (1978); O’Dor and Durward (1979); Durward et al. (1980); O’Doret al. (1980b, 1982b, 1986); O’Dor (1983); O’Dor and Balch (1985); Rowell et al.
(1985a); Perez (1994).
2
Vecchione (1979); Amaratunga (1980a); Durward et al. (1980); O’Dor (1983); Trites (1983); Dawe and Beck (1985); Hatanakaet al. (1985); Rowell and Trites (1985);
Rowell et al. (1985a); Vecchione and Roper (1986); Young and Harman (1988); Mann and Lazier (1991); Perez (1994).
3
Squires (1957); Vecchione (1979); Amaratunga (1980a); Amaratunga et al. (1980b); Fedulov and Froerman (1980); Daweet al. (1981a); Coelho (1985); Rowell et al.
(1985a); Black et al. (1987); Nigmatullin (1987); Perez (1994); Dawe and Beck (1997); Brodziak and Hendrickson (1999).
4
Frost and Thompson (1933); McLellan et al. (1953); Squires (1957, 1967); Templeman (1966); Mercer (1973a, b); Mercer and Paulmier (1974); Bowman (1977);Mesnil
(1977); O’Dor et al. (1977, 1980a); Amaratunga et al. (1978, 1980a); Lange (1978); Lux et al. (1978); Palmer and O’Dor (1978); Amaratunga and McQuinn 1979;
Fedulov and Froerman (1980); Hurley (1980); Whitaker (1980); Dawe and Drew (1981); Dawe et al. (1981b); Grinkov and Rikhter (1981); Lange and Johnson (1981);
Scott (1982); Wigley (1982); Amaratunga 1983; Waldron (1983); Roper et al. (1984); Coelho (1985); Dawe and Beck (1985, 1997); Rowell et al. (1985b); Vecchione et
al. (1989); Laptikhovsky and Nigmatullin (1993); Perez (1994); Felley and Vecchione (1995); Brodziak and Hendrickson (1999); Hendrickson (2004).

Table 1. Cont’d.
Life Stage Prey Predators Spawning Notes
Eggs 1
Spawning has bee induced in the
lab, but not observed in the wild.
Lab studies indicate that egg
masses are spawned pelagically.
Eggs that are presumably spawned in
Gulf Stream waters can hatch in
northern shelf waters > 12.5ºC
(transported by Gulf Stream at rate of
7 km/hr); can also hatch in warm Gulf
Stream waters.
Paralarvae 2
Hatchling:
1.0-1.1 mm
Paralarvae:
1.2-5.0 mm
Transitional:
5.1-6.9 mm
Hatchlings may spend early
life in remains of egg mass to
utilize the nutrients for food.
Yolk-sac not especially large;
food must be adequate to
sustain hatchling during this
stage of rapid growth and
increased metabolism.
Gulf Stream may be important mode
of transportation for paralarvae
throughout range in NW Atlantic;
initially flows northeastward along
shelf, off Cape Hatteras, then flows
easterly and creates eddies in which
young are transported westward into
slope waters.
Pre-
recruits 3
≤ 10.0 cm
Primarily feed on crustaceans
(euphausiids) at night near
the surface; also consume
nematodes and fish.
Gulf Stream presumably transports
juveniles northward; hydrographic
variability in this system may explain
annual abundance differences.
Recruits 4
≥ 11 cm
Visual predators; feeding rate
reduced in highly turbid
waters. Feed primarily on
fish and are cannibalistic
(larger females cannibalize
smaller males, increased in
autumn). Fish prey includes
juvenile Atlantic cod,
mackerel, redfish, sand lance,
Atlantic herring, and adult
capelin. Seasonal/ontogenetic
diet shifts, during spring
(offshore): euphausiids;
during summer-fall (inshore):
fish and squid.
Many pelagic and
benthic fishes feed
heavily on Illex,
including bluefin tuna
and silver and red hakes.
Other fish predators
include shark and
dogfish species, fourspot
flounder, Atlantic cod,
swordfish, bluefish,
goosefish, and sea raven.
Mammalian predators
include common dolphin
and pilot whales. Avian
predators include
shearwaters, gannets,
and fulmars.
Spawning likely pelagic and
occurs during October-July.
Late May: mated females
indicate spawning area (113-377
m) in Mid-Atlantic Bight;
overlaps with fishing grounds.
Winter: presumably spawn
during December-March in the
Gulf Stream and/or south of
Cape Hatteras where Illex sp.
hatchlings were collected.
Lab studies indicate females
mate, spawn once (may release
multiple egg masses), then die
within a week. Mated females
collected in Mid-Atlantic Bight
indicate females may mate with
as many as four males.
Diel vertical migrations: more
abundant on bottom at dawn/dusk and
day than at night; feed primarily at
night before sunrise near surface or
mid-water. Migrate to bottom or
deeper waters during daytime. Change
color to camouflaged pattern when
resting on bottom to reduce risk of
predation by benthic species.
1
O’Dor et al. (1980b, 1982a, 1986); O’Dor (1983); Rowell et al. (1985a); Perez (1994).
2
Durward et al. (1980); Trites (1983); Rowell and Trites (1985); O’Doret al. (1986); Vecchione and Roper (1986); Csanady and Hamilton (1988); Mann and Lazier (1991);
Perez (1994).
3
Amaratunga et al. (1980b); Dawe et al. (1981a); Coelho (1985); Arkhipkin and Fedulov (1986).
4
Templeman (1944); Squires (1957, 1966, 1967); Vinogradov (1970, 1972, 1984); Butler (1971); Mercer and Paulmier (1974); Maurer (1975); Langton and Bowman
(1977); Bennett (1978); Durwardet al. (1978); Hirtle (1978); Ennis and Collins (1979);Froerman (1979); Vinogradov and Noskov (1979); Amaratunga (1980b, 1983);
Amaratunga et al. (1980a); Fedulov and Froerman (1980); Hurley (1980); Lange and Sissenwine (1980); O’Dor et al. (1980a, b); Brown et al. (1981); DeMont (1981);
Hirtle et al. (1981); Wigley (1982); O’Dor (1983); Lily and Osborne (1984); Dawe and Beck (1985, 1997); Maurer and Bowman (1985); Nicol and O’Dor (1985); O’Dor
and Balch (1985); Rowell et al. (1985a); Stillwell and Kohler (1985); Major (1986); Scott and Scott (1988); Vecchione et al.(1989); Laptikhovsky and Nigmatullin
(1993); Perez (1994); Dawe et al. (1997); Brodziak and Hendrickson (1999); Hendrickson (2004).

Figure 1. The northern shortfin squid, Illex illecebrosus (from Goode 1884).

Figure 2. Hypothetical migration path of the northern shortfin squid, Illex illecebrosus.
From Black et al. (1987).

Figure 3. Spawning area of northern shortfin squid (encircled) during late May.
Based on the distribution of mated females (Hendrickson 2004).

Diet Composition of Major Prey Items
Pre-recruits
0
20
40
60
80
100
Well Digested
Prey
Cephalopods Misc.
Crustaceans
Euphausiids Misc. Fish
Percent
Diet
Composition
(g)
Recruits
0
15
30
45
60
Well Digested
Prey
Cephalopods Misc.
Crustaceans
Euphausiids Misc. Fish
Percent
Diet
Composition
(g)
Figure 4. Percent by weight (g) of the major prey items in the diet of northern shortfin squid.
From specimenscollected during NEFSC bottom trawl surveys from 1973-2001 (all seasons). For details on NEFSC diet
analysis, see Link and Almeida (2000).

Figure 5. Distribution and abundance of northern shortfin squid from Newfoundland to Cape Hatteras.
Based on research trawl surveys conducted by Canada (DFO) and the United States (NMFS) from 1975-1994
(http://www-orca.nos.noaa.gov/projects/ecnasap/ecnasap_table1.html).

Figure 6. Seasonal distributions and abundances of pre-recruit northern shortfin squid collected during NEFSC bottom
trawl surveys.
From NEFSC winter bottom trawl surveys (1981-2003, all years combined). Distributions are displayed as
presence/absence only.

Figure 6. Cont’d.
From NEFSC spring bottom trawl surveys (1968-2003, all years combined). Survey stations where pre-recruits were not
found are not shown.

Figure 6. Cont’d.
From NEFSC summer bottom trawl surveys (1969-1995, all years combined). Distributions are displayed as

Figure 6. Cont’d.
From NEFSC fall bottom trawl surveys (1967-2003, all years combined). Survey stations where pre-recruits were not

Figure 7. Distribution and abundance of pre-recruit northern shortfin squid in Massachusetts coastal waters.
From fall Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Survey stations where pre-
recruits were not found are not shown.

Figure 8. Seasonal distributions and abundances of recruit northern shortfin squid collected during NEFSC bottom
trawl surveys.
From NEFSC winter bottom trawl surveys (1981-2003, all years combined). Distributions are displayed as

Figure 8. Cont’d.
From NEFSC spring bottom trawl surveys (1968-2003, all years combined). Survey stations where recruits were not

Figure 8. Cont’d.
From NEFSC summer bottom trawl surveys (1969-1995, all years combined). Distributions are displayed as presence
absence only.

Figure 8. Cont’d.
From NEFSC fall bottom trawl surveys (1967-2003, all years combined). Survey stations where recruits were not found
are not shown.

Figure 9. Distribution and abundance of recruit northern shortfin squid in Massachusetts coastal waters.
From fall Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Survey stations where recruits
were not found are not shown.

NEFSC Bottom Trawl Survey
Spring/Pre-recruits (<= 10 cm)
0
5
10
15
20
25
30
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Bottom Temperature (°C)
Percent
Trawls N=10879
Occurrence N=340
Catch N=3659
0
5
10
15
20
25
30
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-120
121-140
141-160
161-180
181-200
201-300
301-400
401-500
>500
Bottom Depth (m)
Percent
Trawls N=12514
Occurrence N=382
Catch N=4816
0
10
20
30
40
50
60
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
Salinity (PPT)
Percent
Trawls N=2270
Occurrence N=102
Catch N=1645
Figure 10. Distributions of pre-recruit northern shortfin squid and trawls from NEFSC bottom trawl surveys relative to
bottom water temperature, depth, and salinity.
Based on NEFSC spring bottom trawl surveys (temperature and depth: 1968-2003, all years combined; salinity: 1991-
2003, all years combined). Light bars show the distribution of all the trawls, dark bars show the distribution of all trawls
in which northern shortfin squid occurred and medium bars show, within each interval, the percentage of the total
number of northern shortfin squid caught. Note that the bottom depth interval changes with increasing depth.

Fall/Pre-recruits (<= 10 cm)
0
5
10
15
20
25
30
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=11467
Occurrence N=818
Catch N=8405
0
2
4
6
8
10
12
14
16
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-120
121-140
141-160
161-180
181-200
201-300
301-400
401-500
>500
Bottom Depth (m)
Percent
Trawls N=13433
Occurrence N=1009
Catch N=10382
0
5
10
15
20
25
30
35
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
Salinity (PPT)
Percent
Trawls N=2272
Occurrence N=198
Catch N=1224
Figure 10. Cont’d.
Based on NEFSC fall bottom trawl surveys (temperature and depth: 1967-2003, all years combined; salinity: 1991-2003,
all years combined). Light bars show the distribution of all the trawls, dark bars show the distribution of all trawls in
which northern shortfin squid occurred and medium bars show, within each interval, the percentage of the total number
of northern shortfin squid caught. Note that the bottom depth interval changes with increasing depth.

Massachusetts Inshore Bottom Trawl Survey
Spring/Pre-recruits (<= 10 cm)
0
20
40
60
80
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=2407
Occurrence N=5
Catch N=16
0
20
40
60
80
100
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
66-70
71-75
76-80
81-85
Bottom Depth (m)
Percent
Trawls N=2482
Occurrence N=5
Catch N=16
Figure 11. Distributions of pre-recruit northern shortfin squid and trawls in Massachusetts coastal waters relative to
bottom water temperature and depth.
Based on spring Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Light bars show the
distribution of all the trawls, dark bars show the distribution of all trawls in which northern shortfin squid occurred and
medium bars show, within each interval, the percentage of the total number of northern shortfin squid caught.

Fall/Pre-recruits (<= 10 cm)
0
5
10
15
20
25
30
35
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=2244
Occurrence N=28
Catch N=64
0
5
10
15
20
25
30
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
66-70
71-75
76-80
81-85
Bottom Depth (m)
Percent
Trawls N=2338
Occurrence N=28
Catch N=64
Based on fall Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Light bars show the

Spring/Recruits (>= 11 cm)
0
5
10
15
20
25
30
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=10879
Occurrence N=770
Catch N=9321
0
5
10
15
20
25
30
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-120
121-140
141-160
161-180
181-200
201-300
301-400
401-500
>500
Bottom Depth (m)
Percent
Trawls N=12514
Occurrence N=874
Catch N=10504
0
20
40
60
80
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
Salinity (PPT)
Percent
Trawls N=2270
Occurrence N=120
Catch N=2119
Figure 12. Distributions of recruit northern shortfin squid and trawls from NEFSC bottom trawl surveys relative to
bottom water temperature, depth, and salinity.
Based on NEFSC spring bottom trawl surveys (temperature and depth: 1968-2003, all years combined; salinity: 1991-
2003, all years combined). Light bars show the distribution of all the trawls, dark bars show the distribution of all trawls
in which northern shortfin squid occurred and medium bars show, within each interval, the percentage of the total
number of northern shortfin squid caught. Note that the bottom depth interval changes with increasing depth.

Fall/Recruits (>= 11 cm)
0
5
10
15
20
25
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=11467
Occurrence N=4617
Catch N=104051
0
5
10
15
20
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-120
121-140
141-160
161-180
181-200
201-300
301-400
401-500
>500
Bottom Depth (m)
Percent
Trawls N=13433
Occurrence N=5404
Catch N=134252
0
10
20
30
40
50
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
Salinity (PPT)
Percent
Trawls N=2272
Occurrence N=776
Catch N=14760
Based on NEFSC fall bottom trawl surveys (temperature and depth: 1967-2003, all years combined; salinity: 1991-2003,
all years combined). Light bars show the distribution of all the trawls, dark bars show the distribution of all trawls in
which northern shortfin squid occurred and medium bars show, within each interval, the percentage of the total number
of northern shortfin squid caught. Note that the bottom depth interval changes with increasing depth.

Spring/Recruits (>= 11 cm)
0
5
10
15
20
25
30
35
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=2407
Occurrence N=4
Catch N=6
0
10
20
30
40
50
60
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
66-70
71-75
76-80
81-85
Bottom Depth (m)
Percent
Trawls N=2482
Occurrence N=4
Catch N=6
Figure 13. Distributions of recruit northern shortfin squid and trawls in Massachusetts coastal waters relative to bottom
water temperature and depth.
Based on spring Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Light bars show the

Fall/Recruits (>= 11 cm)
0
5
10
15
20
25
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Percent
Trawls N=2244
Occurrence N=287
Catch N=2069
0
5
10
15
20
25
30
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
51-55
56-60
61-65
66-70
71-75
76-80
81-85
Bottom Depth (m)
Percent
Trawls N=2338
Occurrence N=294
Catch N=2085
Based on fall Massachusetts inshore bottom trawl surveys (1978-2003, all years combined). Light bars show the

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