es nn ee es T rT TT T T TT T TT
coo. i
HADDOCK
POLLOCK

SILVER HAKE

HAKE

WHITE HAKE

MACKEREL

REDFISH

OWTAIL FLOUNDER

ER FLOUNDER:

“EN FLOLNOER

H FLOUNDER

SEA HERRING
QNER HERRING

OCEAN SOUT

NORTHERN SHRIMP

SQUID Laiigo
SQUID iHex

BLUEFISH
TILEFISH

—
t+—-
—
Lh
J
—
LL
—
|
|
_
GOOSEFISH TT
|
T
t+
-—

q ! Fe es

9 10 20 30 40 5C BO VC BO 30 OO "10 120 130 i4C EC 16C 170 *BO 19C 2CC 21C 22C 230 24C

MEAN TOTAL ANNUAL CATCH (MT) x 103 1969 - 1978

Figure 3. U.S. and foreign commercial catch values (mean total annual catch 1969-1978)
and mean recreational catch from the 1960, 1965 and 1970 Saltwater Angler

survey area shown in Fig. 1

16


flexible. If the stocks are not in good condition, manage-
ment strategies aimed at short-term ends can have quite
different long-term effects. In any case, it is the relative
condition of the stock which can be reliably assessed, not
the yearly stock size.

9) Maximum sustainable yield.

This measure (MSY) provides a useful guide to the
long-range biological productivity of the stocks, provided
that the limitations of MSY are kept in mind. The
maximum sustainable yield given here is based in some
cases on analytical models, and in other cases it is based
on observations of long-range historical catch averages.
It gives an indication, not of what might be taken in any
given year, but of what might be taken on the average
over time, with some years being above average and
some years below. That is, MSY permits potential
productivity of stocks to be compared in a general way.

Year-to-year variations are due to fluctuations in en-
vironmental conditions and condition of the stock. In
some cases, depending upon the history of the fishery,
the vear-to-vear variation is greatly affected by previous
fishing practices. In general, there has been no attempt
to calculate an MSY that could actually be harvested on
the average over time. It should be kept in mind that if
one were to hold catch at the MSY level, the stock would
likely decrease and the resulting average catch would be
lower than the MSY value that initiated the action. In
certain cases this also holds true for effort being fixed at
the levels of harvest for MSY (Doubleday 1977;
Sissenwine 1978). Nevertheless, the comparison of the
values given here do give rough indications of the
differences between stocks and their general long-range
productivity.

10) By-catch.

The final column lists by-catch and distribution. One
of the most important considerations in mixed fisheries
is that a unit of effort may be directed at several species
at the same time. Furthermore, a unit of effort directed
primarily at one species will catch, less effectively,
species that are associated with it in the environment.
Finally, in the mixed fishery situation even if a fisher-
man is capable of directing effort to a relatively pure
species catch, when other species of value are located
close by, the trip often consists of directed effort at
several species; to make an economically viable trip,
fishing is directed at several species. This column lists
the historically-observed by-catches, where data are
available, and also makes inferences from the seasonal,
horizontal and vertical distribution patterns of various
species. For example, certain species which migrate
through the water column may vield relatively pure
catches when they are high in the water column, but
when they are on the bottom during other parts of the
day they become components of the mixed trawl fishery.
Other species occupy seasonally quite separate areas, so
that the by-catch at different periods of the year may be
quite different both in amount and in species composi-
tion.

10

Basic life history data in this table follows Bigelow and
Schroeder (1953) and Grosslein and Azarovitz (in press).
Spawning times are based primarily on Colton et al.
(1979). Information is taken from the documents cited in
the text as augmented by unpublished data in the files of
the Northeast Fisheries Center.

In summary, the information in the table furnishes
important background information upon which
decisions regarding resource utilization can be
realistically made.

SUMMARY AND CONCLUSIONS

During the last twenty-five years, the fishery resources
of the waters off the coast of the Northeastern United
States underwent a large increase in fishing mortality.
The fishery changed from one concentrated on relatively
few stocks to a wide-based industry directed at the total
finfish and squid biomass. Total resource abundance
declined as a result and the annual harvest exceeded
total productivity. Since 1975, the trend has been
reversed, overall fishing effort has declined and the
stocks have begun to recover, now approaching levels
that existed prior to entry of the distant-water fleets.
Certain components of the resources (e.g. haddock) were
fully exploited prior to the entry of the distant-water
fleets and continue to be so today; in these stocks con-
ditions still exist such that the potential fishing effort
can harvest in excess of annual productivity. Some
stocks with a low capacity to rebuild, such as redfish,
yellowtail flounder, and haddock, suffered extremely
heavy fishing mortality imposed by distant-water fleets
over and above that already existing from domestic
harvesters. Yellowtail in the offshore areas are still below
abundance levels of earlier times. Haddock, although
recovered in total abundance, do not yet have the stable
structure of a population capable of consistently
sustaining high harvests. Nevertheless, indications of
future recruitment give hope for achieving this goal
within the foreseeable future.

Of the larger offshore stocks fished primarily by
distant-water fleets, only Atlantic herring on Georges
Bank have not yet demonstrated a start towards
recovery to earlier levels. Even here, however, the poten-
tial for a good incoming year class currently exists and if
such a year class contributes significantly to the spawn-
ing stock for a period of time, even the offshore herring
stocks could approach values observed historically prior
to consistent heavy fishing. As the total resource builds
to a level at which annual productivity is maximized, or
in some cases beyond that level, the concept of stability
must be considered only as an average over all the
resources using the energy flow in the system.

Yearly environmental fluctuations create wide ranges
of abundance within particular species. These fluc-
tuations can be dampened or accelerated depending on


Table 3
Resource Summary Table

Seograohical range;

Age range in

stock structure Growth fished populations Recruitment yaturity
rom Port Sunwell, cB GM SNE-MA 2215+ yr 6B cu 50% mature at 3 yr.
a. Greenland, to 120 0.116 9.257 GM: Presently 1971, Mean age: 2 3 Soawn chiefly in
Cape Lookout, NC 48.1 146.5 112.9 1973, 1974 yr classes GB: better than avg winter. GN-G8
dominate. GM: better than avg
Max. age = 22 yr $B: 1978 catch juction:
Max. length © 183 cn ‘doninated by 1975 yr patio 2.42-1 for GB wyeis owustion
class (49%). 1966, 1960-1975
So. Channe? 1971 also good.
3) MA coast
. Greenland to on B 2.96 yr 8 GM Some mature at age 2;
treras «29,352 Tn 1878: Over 90% Mean age: 2.3 2.7 almost all mature by
L=72.91 cm L==73.20 fisnable stock is age 3.
1975 year class Improving.
Max. age = 18 yr Historically ages 2-4 Soawn Feb-May. Peak in
Max. length = 112 cm dominate catch. Ratio 19.3-1 for 1931-1965; Mar-Apr on GB
1,200-1 for 1966-1978;
2,700-1 for 1931-1978 Max egg production:
age 6
POLLICK
From tabrador ~ «29.215 2-136 yr Mean age: 3.5 78% mature by age 5
vest Sreenland to L2#97.77 em
Cape satteras. Catch dominated by age Ratio 1,8-1 for 1971-1978 Soawn in Massachusetts
Max. age = 23 yr 3-5 fish in recent (age 2). Bay, Stel!wagen, and
i) Nowa Scotia, GM Max. length = 106 cm rs. Strong 1968, 11.6-1 for 1961-1978 So. Channel, Nov-Mar
20 SNE 1971 year classes. North Atlantic Peak late Dec
‘Wewfoundland Banks 8 cM SNE-MA 2-124 yr Mean age: 2 First spawn 2-3 vr
Zaro! ine <70,286 9,182 0.416
L+=60.72 69.41 46.08 GM: 1971 saw a Patio 12.1-1 for 1955-1978, Sawn Jun-Seo, orincé-

2D HAKE
rom Gulf St. Lawn.
and 3rand Bank Newf.
to No. Carolina
1)
2) SNEMA
3) 4M (smal)

ARE
From ulf St. Lawr
ang Grane Sank Newt

to feqinia

Scattan Shelf to 32.

Max. age = 12%, 6 0”
vax. Tength = 65 cm

«0.37
Not for total

ad population,

Las82.6 cm hit for small

{ samoie.

Max. age = 12 vr
Max. length = 75 cm

£, 4 Not available

vax. age = 23 yr
tax. length = 122 cm

shift toward younger
Fisn; ages 2-3 dominated
catch. In 1975-1977, age
3 made up 44% of catcn,
GB: 89% of 1977 catch
age 3-4.

2-106 yr Mean age: 3
In nearly all years, ages
2-3 have dominated catch,
composing 75% of catch in
1975-1976. Shift toward
3-4-yr-olds in 1977, when
they made up 81° of G8

Related to size of sea

scallop population due
to symbiotic relation-
ship in juvenile stage.

Ratio 2.14-1 for 1968-1978

cater.
“ot xroxn. “ot known.
3B Georges Bank
SHE = Southern New England
Mw Middle Atlantic
SM = Gulf of Maine
cc Cape Cod

20

nally Jul, Aug, on NE
GB and Central Gh,
earlier on SNE

Max egg production: age 4.

First spawn <2 yr.

Spawn in summer on So.
feorges and Nantucket
Shoals.

‘Spawn on Continental
Slope of MA Bight
tn sunmer

(cont'd)


INTRODUCTION

The fishery resource of the Northwest Atlantic from
Georges Bank to Cape Hatteras has undergone dramatic
changes in many respects during the course of its
regularly recorded history. Inhabited by over 200
different species of fish, this region has been of major
fisheries importance since the 15th century. A number of
its fisheries (Figure 1) have been of great international
consequence,

In the United States many species are of considerable
importance for recreational fishing. These species either
inhabit coastal waters for prolonged periods of their
lives, or frequent such inshore areas seasonally. The
relative percentages of recreational, foreign, and U.S.
commercial catch contributing to the total catch for each
species in the year 1970 are shown in Figure 2 (Duel
1973, ICNAF 1972a). Data from 1970 have been
presented because it is the most recent year for which
recreational catch estimates are available for all species.
Recreational fishing effort appears to be increasing
(Figure 3) (Clark 1962; Duel and Clark 1968; Duel
1973).

The waters of the Northwest Atlantic, from Georges
Bank to Cape Hatteras are among the most productive
in the world in terms of finfish biomass per unit area.
The current estimate of maximum sustainable yield is
900,000 metric tons (T) for finfish and squid (Brown et
al. 1976). The total average catch of each species in ab-
solute values for 1969-1978 is given in Figure 4 and the
basic commercial and recreational data are given in
Table 1 and Table 2 respectively. The values in Figure 3
represent the sum of all recreational, foreign, and U.S.
commercial catch (food and industrial), and indicate the
magnitude of the fishery for each species relative to ail
others. Average landings totaled 900,000 T and there
were 26 species for which individual averages were 3,000
T or greater.

The major function of fisheries research is to deter-
mine resource productivity, and to evaluate natural
causes of population fluctuations and man’s fishing im-
pact. Natural changes in the environment are factors
largely responsible for fluctuations in fish abundance.
However, the intensity of man’s fishing effort can be the
overriding determinant and is the only controllable fac-
tor affecting abundance.

Fisheries management in the Northwest Atlantic es-
sentially began in 1953, when the International Commis-
sion for the Northwest Atlantic Fisheries (ICNAF), then

three years old, imposed mesh-sized regulations on some
fisheries (ICNAF 1953). Prior to 1960, the area off the
coast of the Northeastern United States was fished
almost exclusively by a coastal fleet of small U.S. vessels
of under 300 gross registered tons (GRT). Fishing effort
was not sufficient to impair the productivity of the
resource as a whole, although a few traditional ground-
fish stocks were near full exploitation.

Landings during the 1950's averaged less than 500,000
T; the total resource was quite stable, and many large
stocks were virtually unexploited. This situation
changed dramatically in 1961, when distant-water fleets
began to fish Atlantic herring! on Georges Bank and in
the course of this activity discovered large groundfish
stocks. Subsequent fishing etfort was directed towards
groundfish in the 1960's, and catches of groundfish and
squid rose to 700,000 T in 1963 (ICNAF 1967). Ground-
fish catches subsequently declined. and as a result, effort
was again shifted towards herring and also mackerel,
resulting in a peak catch of 670,000 T of principal
pelagics in 1971 (ICNAF 1972a). Landings of other fin-
fish rose to 215,000 T in 1969 (ICNAF 1971) and landings
of squid rose to a 57,000 T peak in 1973 (ICNAF 1975)
(Canada is the basic source of fishery statistics for this
area). Landings for all species averaged about 1.2 x 10°
MT for 1971-1973 (ICNAF 1972b; ICNAF 1974a; ICNAF
1975). This is substantially larger than the MSY of 900.-
000 MT estimated by Brown et al. (1976). Many of the
stocks heavily fished during this period of expansion suf-
fered dramatic declines in abundance in the early 1970’s.
By 1974, a comprehensive management regime had been
instituted under ICNAF (ICNAF 1973, 1974b). Since
passage of the Fisheries Management Conservation Act
in 1976, overall fishing (predominantly distant-water
fleets) has been even further reduced. While there have
been considerable increases in the overall resources,
some stocks have not yet recovered.

This paper reviews the recent history and current
status of fisheries for 28 important species in the
Northwest Atlantic plus total finfish and squid. Current
estimates of biological conditions that reflect production
potential are presented in Table 1. Both research survey
and commercial data are used for these reviews. The sur-
vey indices are those from bottom trawl surveys made by
the Northeast Fisheries Center of the Nationai Marine
Fisheries Service (see Grosslein 1969 and Clark. 1979 for
description of survey).


4,000

3,000 +
wn
Re
i=)
i=
~~?
—
S 2,000 -
g
i=
le}
n
3
is}
c
1,000 }-
@) _

1960 1965
Year of Survey

Figure 4. Salt water angling effort: 1960, 1965 and 1970.

_
a

1970


Table 3. cont’d

Natural Fishing
Mortality Mortality

Abundance

By-catch/
Distribution

MACKEREL (cont. )

2150.3 Fy 120-4
Fagg) -0-1.6
Feurrent = 0.15

{ages 4+)
1962-1978 data

REDFISH (cont.)

20.1

Fqax70-5-1.9 in
excess

2 average all

year classes, 1933-

1963.

Fs

-4 for more recent

Rank 2
Increased 30% beginning 1979 from 1977 low
which was 82% below 1969 peak.

Increase in near future dependent on 1978
year class.

Rank 2

Increasingly dependent on 1971 year class.
1978 survey index 22% less than 1963-1978

average. Population much lower than during
peak catches in 1940's

year classes, 1955-1963.

F current

YELLOWTAIL (cont. )

20.2 GB SNE-MA
Fo1 0.3 0.3

Frax 0-5 9.5

Feurrent 1.03 0.37
for 1978

‘WINTER FLOUNDER (cont. )
So. oF cc
(Prob-

‘SUMMER FLOUNDER {cont.}

M=0.2 20.3 in 1977

AMERICAN PLAICE (cont. )

No est- Not known
imates

availaole

Life nis-

tory would

indicate

20,2

20.5, 1976-1977.

Rank 1

Yellowtail! abundance is estimated at below
peak periods.

SNE 1978 index is 70% lower than 1967-1979
average.

GB 1979 index is 56% lower than 1964-1978
average.

"A-1973 index is 89% lower than 1963-1978
average.

Rank 3
Abunaance has increasea in recent years but
not to peak levels. Recruitment appears to
be good.

1978 GB survey index is 26% greater than
1962-1978 averace; 1978 SNE survey index
30% less tnan 1963-1978 average, 1973 GM
survey index is 33% Tess than 1963-1973
average

Rank 3
Abundance levels anoear to be low relative
to recent years.

631978 survey index is 13% greater than

1973-1978 average; SNE 1978 index is 9% less
than 1963-1978 average; NA 1973 index is 95%

jess than 1967-1978 average.

Rank 3
GM indices increasing since 1972 and
greater in 1977 than any year since 1966.

Newf., SNE, GB, MA =
210,G00-230,000 T

GM, GB = 14,020 T

At current abundance,
Fishing at MSY effort
would yield 5,200

SNE-MA = 23,000

20,000-22,000 “T

while pelagic, can be caught with
bottom trawis, and at that time
will have other groundfish as
by-catch, i.e., herring, hakes.
Generally inshore, then NE migra-
tion in spring for spawning.
Tagging shows extensive movenent

Relatively oure fishery; 38% oure
between 1968 and 1978. However
redfish are taken in mixed qrounat
Fisheries and GM shrimo fishery

Demersal

Nonmigratory

Cod, haddock, ctner sroundf
and flouncers

Demersat

Annual migration to SNE-Nantucket
Shoals area moves west in winter
and east in summer.

Cod, haddock.

d other crouncé,
Denersal

winter spawning migrations into
Days and estuaries - not extensive.

“ixed groundf., winter flounder,
Loligo, scup, etc.

demersal
Autumn migrations to offsnore win-

tering grounds where it Tixes with
Toligo.

Dthar flounsers, 20a other aroundt
demersal

No significant vigrations

(cont'd)


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Butterfish

Buttertish were the basis of a very modest U.S. fishery
prior to 1960: after which these were subjected to in-
creased exploitation from the distant-water fleets
(Murawski et al. 1975). As a result, the population
became dominated by younger age groups (Murawski
and Waring 1978). Recently, the reduction in the
distant-water fleet catch has resulted in a decrease in
fishing mortality rates and an increase in the average age
of the fish in the population. Recent survey cruise total
abundance indices are slightly lower than the 1963-1978
average. as is the recruitment index. Nevertheless, sur-
vey indices are still well within the range of values
necessary to support a fishery larger than that now
existing.-”

Spiny Dogfish

In the Northwest Atlantic the spiny dogfish ranges
from Newfoundland to North Carolina, and is common
" continental shelf waters down to 200 m (Jensen 1965).
It undergoes diel vertical migrations, with daytime
catches considerably larger than those at night. The
spiny dogfish is among the most numerous species in the
Northwest Atlantic. The estimated range of total
biomass for the New England area alone is from 170,000
T to 225,000 T.** Despite the large biomass of the
species. the market (both food and industrial is very
small. The catch of the species in the Northwest Atlantic
in most vears has been significantly below the total
production of the fish.” Recently, the U.S.A. has
developed a small export market of about 2,000 T of
dogfish fillets with the European nations; this has in-
creased in 1979. The reproductive potential of the
dogfish is relatively low; it is unlikely that the stock
could sustain a yield of over 20% of its size for a con-
tinued period of time (Holden 1968). The 1978 survey in-
dex for spiny dogfish shows no appreciable change from
the 1967-1978 average.

Angler-Goosefish

Clark and Brown (1977) estimated the biomass of
angler at 18,000 T based on survey data from 1968 to
1974 for Browns Bank, Nova Scotia, to Cape Hatteras.
Both food and industrial use of goosefish is low. The
U.S.A. is responsible for only 4° of the removals per year
from Cape Hatteras to the eastern end of the Nova Sco-
tian Shelf since 1966. The U.S.S.R. has taken most of
the remaining 96°. Since 1966, landings for food have
increased. The 1978 survey index is 31% greater than the
1967-1978 average, and the 1977 and 1978 values are the
largest seen since 1972.

Ocean Pout

Knowledge of historical trends in the ocean pout
fishery is somewhat obscure. In the New England area,
commercial landings were negligible up to and during
the 1930’s and most of the catch was discarded. Land-
ings fluctuated between 21 and 52 T from 1935 to 1942.
In 1943, attempts to market ocean pout as a food fish

were frustrated by parasitic lesions caused by a proto-
zoan, which proved to be a recurring problem (Sheehy et
al. 1974). During the 1950's, U.S.A. landings were almost
entirely industrial. Ocean pout comprised a substantial
part of the total U.S. industrial fishery between 1970 and
1974. Distant-water fleet vessels were involved in the
fishery from 1966 to 1974, peaking in 1969 at 27,000 T. It
declined to an average level of 5,600 T from 1970 to 1974.
Since 1974 the ocean pout fishery has been essentially
domestic only. Declines in relative abundance of 74% for
Southern New England and 82% for Georges Bank have
been reported for the period 1963 to 1974 (Clark and
Brown 1977). Total U.S.A. landings in 1977 were 1,060
T; more than 50° of these were marketed as food fish.
The 1978 survey index is 51% greater than the 1976 to
1978 average. Years with poor indices seem to be
preceded by vears of relatively heavy fishing.

Northern Shrimp

Landings of northern shrimp from the western Gulf of
Maine peaked at 13,000 T in 1969 but have recently
become essentially non-existent. Water temperatures
are declining and may be more favorable now than in the
recent past for production of good year classes to build a
larger spawning stock and a single year class fishery. In
latter years, fishery effort has concentrated on several
age groups including small males prior to their transfor-
mation into female spawners; historically the Maine
winter fishery focused on egg-bearing females (Anthony
and Clark 1978; Clark and Anthony, in press; Dow 1977:
Wigley 1973).**2° At this time the fishery is closed to
allow the stock to recover to levels at which good
reproduction can be expected more frequently.

Loligo Squid

Loligo squid populations are very volatile; the species
has a short life span, and exhibits drastic year-to-year
changes. Although records of squid were not kept in the
early vears of the survey cruises, they were relatively low
in abundance during most of the 1950's. In the late
1960's, the population expanded rapidly and has con-
tinued to expand through the 1977 period (Lange and
Sissenwine, in press). During this time, an extensive
fishery was developed by the distant-water fleets. Since
the implementation of the FMCA this fishery has con-
tinued but at lesser harvest levels. The U.S.A. fishery
remains small. The 1978 fall survey index was low. but
Loligo squid were abundant in the spring surveys at
smaller lengths than usual, indicating that in 1978 there
had been a late spawning.*° Thus. in terms of numbers.
abundance remains at the high levels observed over the
last decade.

Illex Squid

Illex squid are a species with a short life span (about 1
year) which can also exhibit drastic changes in abun-
dance from year to year. Since environmental conditions
tend to be similar in adjacent years, abundant years
tend to occur together, as do poorer vears. In the last few


Table 3. cont’d
Natural Fishing By-cateh/
Mortality Mortality Abundance msy Distribution
TOLTGO Teont.7
FETS Not known Rank 2
ign mor- Autuan surveys from 1967 inaicated SNE, SB, MA = Intensive by-catcn Doth offshore
tality general increase, but trend nas been 44,000 T and insnore mixtures. gutterf#sh
after downward in 1977-1978. is the major by-catch.
spawning. Minimum biomass range: 14,000-52,000 7 haat frequents
Population size range: 1,100-4,800 T Sasically gelagic, dut frequents
million individuals (lowest since 1971) rear-bottom waters
Migrate inshore each spring %
scawn and affshore in winter
ILLEK (cont.)
Me1.56 Not known Rank 3 GM, SNE, GB, MA = Intensive by-catch noth of fshore
Heavy Survey indices were well below 10 yr average 30,000 7 and inshore. Mixtures of grouncf.
post in al} but SNE area - increased in 1978 to soecies taken when fisned near
spawning 1978 evel of hign abundance by rumber, row- Gulf of St. Lawr. notton
mortals ty every wt/tow was 39° less than in 1376 in- and Grand Sank of belanic
after 1 dicatrng smaller individuals (second highest Newfound]. = «
yr of age. since 1968) 320,000 T Move offsnore in autumn ‘ato deeper,
warmer water.
SLUEFISH (cont.)
Current jevels Rank 4 89,900 T Not significantly ‘ished commer-
of catch are at 1978 survey index is 13% greater than cially
. MSY 1967-1973 aver 5
about “SY Tevel 367-1973 averace oelacic
Catches averaged increased since the 1960's staple Aoorecaté . vewar
1975-1978 = jevel in the 1970's aggregations travel northward ir
23.200 t spring and summer, soutnwars in
: fal! and winter
LIREFISH (cont)
not Not available Rank 2 Not availaple Lobster and surmer flounder yout «!t
avail Not available fitle traw! cormerzia? cattr tne
able numbers woul: not ne s:gnificart

Total FINF!SH and SQUID {cont.}

For
bulk
oF
Fishery
oiomass

would be
aopro-
priate
average

Probably about 0.4 Rank 2

Biomass declined uo to 59

1963-1978

Since 1975, total biomass levels aopear
to nave increased significantly

U.S, GOVERNMENT PRINTING OFFICE: 1981

900,000 * (1976)

701-242/20

Demersat

Do not migrate extensively


Table 3. cont'd

Geographical range: Age range in
stock structure Growth fished vopulations Recruitment Maturity

Reach 60% of maximum 2-15 yr No available data Mature at age 2
size by age 3
Two subpopulations Catch dominated by Spawns May-Aug,,
« 195 2-3 yr fish Peaks May-mid-JuT
i) 3: les 40.79
2) Yew Jersey
Max. age = 19 yr
Max. length = $3 cm
BUTTERFISH
rom Newfound]. to Fi Fastest in Ist yr & de- 1-6 yr Recruitment lower than Mature at age 1-2
creases in each following During 1974-1976 age average; trend of de-
1) So. of Cape roup - + and I+ creasing age at recruit-  Spawns MA to SW GB
watter: 961 Fish dominated catch ment since 1970; 1971 yr May-Aug
Yo. 21 cm class was most abundant
satteras Peaks in Jul
Max. age > 6 yr Age at entry = 0+
Max. length = 30 cm
SPINY DOGFISH
From Labragor to FL Rate - 3.2 om/yr No information available No available data Mature at age 9+
Evidence of movenent «
across Fundian Channel; Les not available Range - not known Young born Kov-Jan
migrations May sustain moderate Ovoviviparus
Max. age = 30 yr fishing mortality rates Young born Nov-Jan
Max. Tength = 110 cm Primarily dy-catch 2 yr cycle
ANGLER (GOOSEF ISH)
From Grand 3anks of New- 10 ca/yr No available data No available data Mature at age 4 #
foun! % Suif of St. kong Tived (59
Laue. to Ve EZ $ not availaole
Stock oreakdown not Les Spawn spring, summer,
available but areas and early autumn
of conc. are Max. age = 30 yr according to latitude
Max. length = 122 cm
1} Nantucket Snails
,
2) gM
OCEAN PGUT
Frow Lapragor So. to Stower in northerty 4210 yr No available cata g's between 5-9 yr
Delaware Bay areas Dominant ages not a
<*% not available available s between 2-3 yr

L

Max. age = 12 yr
Max. length = 28 om

Spawns Sep-Oct

ORTHERN SHR

EMP

‘umoolar = No «< not avarlabie In 1977 age 3+ shrimo Estimate decline over 95% Hermaphroditic &~ 2
Ariane. area, t dominated caten during 1969-1977
from Barents sea Enter fishery at tyr o's mature age 2
westward to afin wax. age = 6-7 yr Recruitment Seems to be Q'S mature age 3
Islana ang soutn- Max. length related to both temo-
wars co OM (carapace) erature and to removals Peak hatching occurs
of oarent soawning stocks. in late Feb - early Mar
1) SM (western
(cont'd)

26


Pollock

Pollock is a transboundary stock found on Georges
Bank, the Scotian Shelf, and in the Gulf of Maine. The
primary spawning area appears to be in the
southwestern Gulf of Maine (Clark et al. 1977). Both
Canada and the United States have increased their
pollock fishing in recent years. Indications are that
pollock are now at a level of abundance slightly higher
than a few years earlier although current catch statistics
are questionable, making it difficult to indicate the
predicted catch for a given level of effort. There is some
indication that catch per unit effort in the commercial
fishery may be declining slightly, this and certain
biological considerations support a conclusion that a
fishing mortality lower than currently existing in the
fishery would result over time in maintaining a higher
sustainable catch rate, a more abundant stock size, and
greater stability in the fishery. Catch levels about 20%
lower than at present'° would be required to achieve this.

Silver Hake

Silver hake are found on the Nova Scotian Shelf south
to the Middle Atlantic. General distribution studies in-
dicate that the Nova Scotian, Georges Bank, Southern
New England-Middle Atlantic, and the Gulf of Maine
fish have some degree of stock separation, with the
greatest degree of separation being with the Nova Sco-
tian stock. Stock analyses (Anderson et al., 1980) in-
dicate that trends in abundance in these three southern
stocks have differed over the years. There are also
morphometric studies (Conover et al. 1961) reporting
stock differences indicating some degree of separation
and differential response to fishing pressure.

Silver hake spawning stocks on Georges Bank in-
creased about six-fold from the middle 1950's to a peak
in the middle 1960’s, then declined to somewhat lower
levels as fishing mortality increased greatly with entry of
the distant-water fleets. Following removal of that effort.
the stock has recovered to levels approximately 1'2 to 2
times that of the middle 1950’s, but only to about ‘3 to
“4 of the peak period size (Anderson et al., 1980). The
stock now appears to be stabilizing with recent recruit-
ment at lower levels.

The Southern New England-Middle Atlantic stock of
silver hake was exploited by a U.S. industrial fishery in
the 1950’s. The population increased six-fold to a peak in
the middle 1960’s and then declined to levels slightly
above those existing in the 1950’s (Anderson et al.,
1980). With reduction of fishing mortality and the oc-
currence of strong year classes, the stock is rebuilding
and is now almost as large as it was during much of the
1960's.

Silver hake in the Gulf of Maine declined steadily
during the latter half of the 1950’s and throughout the
1960's. reaching low points in the 1970’s. Poor year
classes occurred during the latter 1960’s. Since that
time, year class strength has improved but not to the
ievels observed previously. The demise of the U.S.A.

shrimp fishery with its associated by-catch of immature
silver hake may be a factor in the improvement seen in
this particular stock through 1978. Very high fishing
rates occurred in the late 1950's and the very early 1960’s
(Anderson et al., 1980). Since then, fishing mortality
has been reduced, assisting recovery of the stock. The
spawning stock is now about one-third of that observed
at peak levels, but about three times that observed at the
lowest level of abundance.

Red Hake

Red hake are located primarily in the Georges Bank.
and Southern New England-Middle Atlantic area.
Distribution studies and following trends in abundance
suggest that the Southern New England-Middle Atlan-
tic fish are to some extent separate from those on
Georges Bank.'' The Georges Bank stock was essentially
unfished until the middle 1960's entry of the distant-
water fleets. The accumulated stock was harvested and
reduced to a level at which the fishery depended on an-
nual productivity. From the later 1960’s, the spawning
stock increased somewhat into the early 1970's. [t has
been reduced to slightly lower levels at the present
time.'? The Southern New England-Middle Atlantic red
hake stock has a longer history of fishing being an impor-
tant component of U.S.A. industrial catches in the
1950's. It also supported very high catches in the middle
1960's as a result of the entrance of the distant-water
fleets. Fishing effort has since decreased. Abundance
trends are available only for the more recent period.
They indicate a relatively steady decline in abundance
from peaks in the latter 1960’s and the early 1970's, when
the stock size was about twice that at the present time.
Indications are that the recent year classes are somewhat
larger than those in the early 1970’s.'*

White Hake

White hake may possibly be considered as a single
stock throughout the Scotian Shelf, Gulf of Maine, and
Georges Bank area.'* Centers of abundance appear to lie
in the deep areas of the Gulf of Maine. Catches have in-
creased considerably in the 1970's. Canada taking the
largest proportion. NEFC bottom trawl! surveys indicate
that the stock has remained relatively constant since
1968 somewhat more abundant than earlier.'4 The extent
to which sustainable catches could be increased is not
known.

Atlantic Mackerel

Atlantic mackerel range from Cape Hatteras to New-
foundland (Sette 1950: Anderson and Paciorkowski. in
press). Stock biomass declined in 1977 to a low point
about one-fifth of the 1969 peak, approximately to the
level of the early 1960's; it has begun to recover since.
Spawning stock has declined to a low level in 1979, but
survey data indicate that it should begin to recover
shortly.'* The peak population resulted trom recruit-



SYNOPSES OF SPECIES

Atlantic Cod

Four major geographical groups of Atlantic cod have
been recognized in the waters off the northeastern
United States: Gulf of Maine, Georges Bank, Southern
New England, and the New Jersey coast (Wise, 1962).*
Studies indicate that intermingling between the Gulf of
Maine and the other groups is minimal while mixing
between the three southerly groups is more extensive,
particularly between the three Southern New England
and the New Jersey populations. South of Long Island,
cod eggs and larvae have been routinely recorded
although the virtual absence of juvenile cod in the
southern area compared to the number of adults suggests
that the New Jersey population may not be self-
sustaining.’ In addition to exchanges within these areas
otf the northeastern United States, there is also some
movement of the Gulf of Maine fish into and out of the
Bay of Fundy, and some minor exchanges across the
Fundian Channel from Georges Bank, to the Scotian
Shelf and Browns Bank. Cod have a long history of com-
mercial fishing in the Northwest Atlantic; there was a
considerable increase in the latter part of the 1960’s due
to expansion of USSR. Canadian, and Spanish effort on
Georges Bank.‘ This increased effort and resultant catch
tollowed an apparently modest increase in the Georges
Bank population size. Following this heavy exploitation,
the population declined and the fishery became more
dependent on current recruitment than formerly. Con-
comitantly. cod became less abundant in more southerly
areas in wintertime than before. Following the reduction
in the fishing effort of the distant-water fleet and the en-
try of the 1971 and 1975 classes into the Georges Bank
population, the catch increased. Presently, the 1975 year
class is maintaining itself in the population longer than
th vear classes preceding it despite fishing effort
slightly above that which might be expected to sustain
the highest catch rate in the long term. This is an indica-
tion both of the size of the year class and the reduced
mortality rate compared to that of the late 1960’s and
early 1970's. The Gulf of Maine catch has increased con-
siderably in recent years following entry into the fishery
of some good year classes. Year classes of cod in the areas
considered in this paper, have not exhibited the extreme
fluctuation found in many other species. Given the past
history of lower catches in the Gulf of Maine, an area
which has had a long history of fishing, concern has been
expressed that cod may not be able to support catches at
the current level for an extended period of time.* *®

Haddock

The haddock stock on Georges Bank has been a classic
for fisnery management. Catch history and scientific
data in the period from 1930 to the early 1960's indicated
a very stable population despite fluctuation in year-class
size (a ratio of 6 to 1 in recruiting year-class size
exciuding the extremely abundant 1963 vear-class and

about 20 to 1 including it).**’ The number of year
classes in the population to a large degree, stabilized the
stock, so that yields averaged close to 50,000 metric tons
throughout the period despite the year class variability.
The stock collapsed in the 1960's. the result of a series of
years with very low year class production. These came
just before the extremely heavy removals by the foreign
fleet in the mid-1960’s lowered the spawning stocks to
10° of earlier years. Throughout the late 1960's and into
the 1970’s, spawning produced low year classes.
Variability was greater than in the earlier periods (100 to
1 excluding 1975 and about 1,200 to 1 including it).”*
This indicates that recruitment at low spawning stock
levels has higher variability, considerably lower sized
year classes on the average, and much less frequent good
year classes. The 1975 year class was extremely strong
ranking with the larger ones that occurred during the
pre-1964 period. The fact that such good year classes oc-
curred so infrequently in the latter period compared to
earlier, supports the overall importance of maintaining
an adequate spawning stock. The 1975 year class was
followed by two poor year classes similar to those just
preceding it. The entry of the 1975 vear class increased
the population by an order of magnitude.* Management
attempted to hold back the removals which, at this pop-
ulation level. would easily have yielded more than 50.000
tons of fish similar to catches occurring during the
1950’s. With the higher fishing mortality rates that the
present fleet is capable of exerting, the consequences of
completely uncontrolled fishing would have been even
more severe. The New England Regional Fisheries
Management Council's goals were to hold back fishing
mortality allowing the 1975 year class to recruit to the
spawning stock, maintaining it at as large a size as possi-
ble until other good year classes recruited. This was in-
tended to result in a more stable spawning stock con-
sisting of several year classes. The results of NEFC
research survey indicate that the 1978 year class. the
first spawned by the 1975 year class, is of a size typical of
the 1930-1960 period.

The 1979 NEFC summer research survey gave
preliminary indications that the 1979 year class may also
fall into that range of values. If these leveis of recruit-
ment continue. the haddock and fishing mortality held
to moderate levels will soon resemble in terms of the
number of age groups, spawning stock. and total abun-
dance, the conditions existing prior to entry of the
foreign fleets. This would imply a continuing yield
averaging between 40,000 and 50.000 T, if fishing effort is
held at moderate levels. It should be realized that yearly
catches will vary about these averages.

Haddock in the Gulf of Maine have appeared over the
years to follow generally the same population trends as
those on Georges Bank. If this pattern continues this
stock will also be in a condition similar to former periods.
Its vield. however. would be on the average about 10 to
20 percent of that on Georges Bank, given histerical
values.~



puja a!

wwoosn{ |

wwo) ubias04 ~ |

4 ONY SALW

7

VIS M

4 IANS

wINU UV

TM AYIEN
DH LLM

mM

is

doo

al catch to the total

S. commerci:

0 tor areas shown in Fig.

f 1, foreign and U

ve percentages of recreationa

Figure 2. Relativ

1.

catch tor each species in the vear |

15


in contrast, indicate a slight decline from the earlier
1960’s to the early 1970's followed by a modest recovery
typical of many of the species which were subjected to
the distant-water fleet fishery before its curtailment.?°

Witch Flounder

Witch flounder, like American plaice, are also found in
deeper water areas, predominantly in the Gulf of Maine.
They appear to be relatively stationary fish and are un-
likely to mix with witch flounder on the Scotian Shelf.
Abundance has been fairly stable throughout the entire
period. However, the lowest survey abundance indices
occurred following the peak removals of the early 1970's,
when total international effort approximately doubled
previous levels.?° The U.S. catch dropped after the early
1970's reaching a low point in 1976; however, in 1977 and
1978 catch and population both seemed to have
recovered.

Atlantic Herring

Atlantic herring spawn in three major areas between
Nova Scotia and Cape Hatteras: on northern Georges
Bank, on the southwest part of the Gulf of Maine (Jef-
freys Ledge) and off Nova Scotia (Lurchers Shoals).
There have been fisheries for adults on the spawning
grounds, and more recently on the over wintering and
spring concentrations in which there appears to be some
degree of intermixture between stocks. Furthermore,
there is a juvenile fishery along the coasts of Maine and
New Brunswick. All herring spawning stock levels are
now considerably lower than in the 1960’s (Anthony and
Waring 1980, in press). The Georges Bank stock still
appears to be extremely small as a result of the con-
tinued heavy fishing effort during a period of poor year-
class production, with no firm indication as yet of
rebuilding of this stock. The Jeffreys Ledge spawning
area had a concentration in 1978 consisting of 1970 and
1973 year class fish. The 1976 year class appears
reasonably strong and supported the bulk of the 1979
fishery in the first part of the year. The extent to which
the spawning stocks rebuild depends on the degree that
they are allowed to accumulate biomass. Three year olds
do not often contribute greatly to the spawning stock on
Jeffreys Ledge but have in certain years been major con-
tributors on Georges Bank (Anthony and Waring, in
press). When Atlantic herring stocks are very low they
may remain low for a considerable period before good
year classes recruit to rebuild the fishery.

River Herring

The river herring fishery is directed towards two
species: alewife and blueback herring. The center of the
fishery is in Virginia and North Carolina. This was en-
tirely a U.S.A. inshore fishery until 1967 when the
distant-water fleets began harvesting river herring in the
offshore regions. At this time the stock declined
precipitously. Despite cessation of the offshore fishery,
spawning success in the major rivers has continued to be
very low, and the stocks are now at historically low

ow

levels.*? In the Gulf of Maine there has been, in contrast,
a gradual but steady increase in recent years, probably
due to improvement in stream conditions resulting from
conservation measures.??

Black Sea Bass

Commercial catch statistics for black sea bass reflect a
steady decline in abundance from a peak in the early
1950’s. A general !ow was reached in the early 1970’s. Re-
cent catches have shown a modest increase but remain
at about 25% of the early 1950’s level. Black sea bass
exhibit a sexual transformation generally between ages 2
and 5, beginning life as females and later transforming
into males (Kendall 1977). Most of the exploited black
sea bass consequently are males. It is postulated by Ken-
dall and Mercer (in press) that heavy fishing pressure
could cause an imbalance in the spawning population so
favoring the number of females that the remaining males
might not be sufficient for adequate reproduction. The
recreational catch is thought to be consistently larger
than the commercial, although data on the recreational
catch is sketchy. In the 1970’s the recreational catch
comprised more than 75% of the total catch of black sea
bass. Survey indices indicate that 1969 and 1974 were
years of relatively high abundance. The 1978 abundance
index was 44° less than the 1967-1978 average.

Skates

Skates have been taken frequently throughout the
history of the U.S. trawl fishery; most of them have been
discarded but some have been landed for industrial and
food purposes. During the period of intense distant-
water fleet fishing, skate catches also increased. The
larger proportion of the catch consisted of big, little, and
thorny skates. Skate abundance in trawl survey catches
has declined in recent vears. Increased U.S.A. trawling
may to some degree be substituting for part of the
distant-water fleet effort. Being a species of relatively
low fecundity, skates can be expected to have a longer
recoverv time than more fecund species. Recruitment
studies based on survey length frequency data indicate
no evidence for the dominant year classes which serve to
speed stock recovery in other species.”

Scup

Historical landings of scup reflect large fluctuations in
population size (Morse 1978). Poor spawning success. in-
creased fishing pressure (both distant-water fleets and
domestic), and high discard levels of juveniles combined
to reduce scup catches dramatically from the early
1960's to the early 1970’s. Landings in the 1970's were
about 20-22% of the peak in the 1960's and the catch in
1973 was 50° less than the 1929-1973 average. The 1976
survey abundance index was the largest in the 1967-1978
data series: the next largest value was in 1969: 36°7 of
i976.*' A three-vear running average for the survey in-
dices shows an increase in 1976-1978 that more than
doubles the average of previous vears in the series



Table 3. cont'd

Natural Fisning , By-catcn/

Mortality Mortality Abunaance MSY distribution

GD (cont.}

0.2 6B Rank 2 GM = 9,000 T Haddock, pollock, yellowtail,
O.1s Both GM and GB cod seem at abundant oopula- GB = 35,000

HADDOCK (cont).

M=9.2

Fort
Frax20.58

Fg y20-5-0.55

F for fully recruited
ages has approx. 0.2
since 1973.

POLLOCK (cont. }

ME0.2 Fg 150.20, recent yrs
Fpgy70-37
Feurrent 0.32 during
1973-1977
i
M204 Fy) Feurrent
2.65 9.33
25 9.39
0.58 9.461

not a calculable

value.

RED HAKE (cont.)

Medd Fy.y Feurrent

WHITE KAKE {cont.}

Not known;
probabiy
low

Not available

tion condition. GB 1978 autumn index is
123% greater than 1963-1978 average {1978
increased 36% over 1977). GM 1978 autumn
index is 38% greater than 1963-1978 average
(1978 27% over 1977).

Rank 1

Recent dramatic increase due to 1975 year
class.
1930-1960, but overbalanced toward a single
year class. GB 1978 fall index 23% iess
than 1963-1978 average. GM 1978 fail index
88% greater than 1363-1978 average

Rank 3.

Relatively strong abundancd GB_1977 fail
index 82% greater than 1963-1977 average
M1977 fall index 81% greater than 1963-
1977 average. Scotian Shelf 1977 fall
index 21% Tess than 1963-1977 average.

Rank 3.

GM stock recovering, remains less than
geak, early 30's. G8 and SNE stock in
good ‘condition but jess than peak
abundance. G8 1977 fall index 3
greater than )963-1977 average, 3M
1377 fall index 12% greater than 1963-
1977 average. SNE-MA 1977 fail index
22% less than 1963-1977 average.

Bank 3

In general, stock appears in Tow condition.
58 1977 fail index 712 greater than 1963-1377
average. SNE-MA 1977 fall index 22% less
than 1963-1977 average; has fluctuated
considerabiy since 60's.

Rank ¢
1978 survey index equai to 1969-1978
average.

i

Tot. pop. abundance reaching range of

Nova
oM

Ge = 40-50,000 7

42,000 T

for Nova

Scotia Shelf, GM,

GB, SNE

oe
SNE-MA

ic :
SNE-MA =

Scotia

7,000 T
35,000 T

13,000 7

26,00C T

otner flounders, aroundfisn.
Demersal

GB stock migrates southwest
in autumn

Cod, yellowtail, otner flounders,
otner aroundfisn

Demersat

Move inshore off Yew England
between Jan and June.

Merring ‘fal! only), groundfish
when Fisning on Dotto.

Pelagic /Demersal
asonal soawning “ovements to
western GM, Scotian Snelf

Pea nake, mackerel, otner ground?

demersal /Pelacic

Densest offsnore; ticrates shora-
ward sorting, sunmer
marate East to SNE waters 17
summer

Silver nake, assorted flounders.
groundfish

Demersat

During autumn aauits are both
inshore/offsnore, but in winter
and early spring they 2acreaate
in deeper, offshore areas.

ed nake, other grourafisn

eral

Insnore movement i
1 autune

5M anc

tcont'd)

NY Bignt fise


NOAA Technical Memorandum NMFS-F/NEC -5

This TM series is used for documentation and timely communication of
preliminary resuits, interim reports, or special purpose information; and
has not received compiete formal review, editorial contro}, or detailed
editing

Northeast Fishery Management
Task Force

The Status
of the
Marine Fishery Resources
of the
Northeastern United States

Margaret M. McBride and Bradford E. Brown

Woods Hole Laboratory, National Marine Fisheries Service, Woods Hole, MA 02543

U.S. DEPARTMENT OF COMMERCE

Philip M. Klutznick, Secretary

National Oceanic and Atmospheric Administration
Richard A. Frank, Administrator

National Marine Fisheries Service

Terry L. Leitzell, Assistant Administrator tor Fisheries
Northeast Fisheries Center
Woods Hole, Massachusetts

December 1980


over time stocks would evolve into quite different species
or subspecies. Intermixture between, stocks can occur in
a number of different ways. Stocks may separate during
part of the vear and be totally intermixed at other times.
Sometimes this intermixture may be more or less ran-
dom within the same schools, but at other times fish
from different spawning stocks may occupy the same
general area but exist in different schools. Furthermore,
even within the area of greatest genetic integrity, that is
within spawning concentrations, there may be a certain
degree of mixture of fish from other areas. The important
point is that there be enough separation among stocks so
that interactions and effects on a stock from one area are
not immediately seen in stocks from other areas.

Yellowtail flounder offer a classic example of stock
structure. After a period of intense pulse fishing by the
U.S.S.R. in the late 1960's, the Southern New England
stock dropped drastically in abundance. If there were a
large degree of intermixture with the stocks on Georges
Bank, there would have been a rapid evening out of the
available fish in both areas. However, this did not occur.
The stock on Georges Bank maintained a higher level of
abundance for several years after the decline in Southern
New England.

Herring stocks are another example. Herring stocks on
Georges Bank began to decline prior to those in the Nova
Scotia area. The result of this decline was shown first in
the lack of abundance of herring in the most southerly
overwintering areas: that is, off Maryland and Virginia.
Resident predator species in that area which depended
on herring as forage shifted to other prey species instead
of moving further north where herring were still abun-
dant. This shows how stock structure may affect interac-
tions between species. While this does not mean that
management units must be based entirely on stock
boundaries, it indicates that stock considerations may
be important and that in evaluating the effects of
Management actions on the resource one needs to
examine them.

2) Growth.

In the second column we list some of the basic
biological parameters describing growth. The values
given where available are:

(a) x, which is a parameter from a von Bertalanffy
growth equation (von Bertalanffy 1938), measures
the rapidity of growth. The larger the x the quicker
the fish grow to L®. The species with the largest «
have the greatst potential for productivity, and also
some of the greatest demands for food on the
ecosystem,

(b) Le, from the same equation—the maximum length
which an average fish would attain if it lived in-
definitely. Individual fish may exceed that average.

(c) Maximum age, which indicates the length of time
that an individual cohort is in the ecosystem and
available to the fishery. This maximum age is not
an extreme age, but only a rough indication of the

oldest fish that have been observed. Fish of this age
would not be expected to be abundant in stocks
where fishing pressure is heavy.

3) Age range in fished populations.

The age range in fished populations is one of the most
sensitive measures of the stability in stock biomass and
its productivity. We use the term ‘fished populations’ to
refer to populations that are undergoing moderate
fishing. The age range is not what would occur in an un-
fished stock nor does it include the very rare older fish in
the moderately fished stock. We also describe the
current range in age distribution with an indication of
predominant year-classes. The comparison of the pre-
sent range of ages with the past gives a good indication of
whether or not the stock is now more variable than would
occur under more moderate fishing.

4) Recruitment.

This column lists the relative range of observed age at
recruitment and the most recent trends. Recruitment is
generally thought to be governed by an underlying stock-
recruitment relationship that comes into play primarily
when a stock is at an extremely low level. However, the
relationship, which limits the amount of eggs produced
in the system, is then acted on by a plethora of en-
vironmental forces, such that good recruitment can come
from even small spawning stock sizes and very poor
recruitment from large stock sizes. Spawning stock size
has its impact on the frequency of distribution of recruit-
ment size. There is a greater probability of good vear
classes when spawning stocks are above some minimal
level. These minimal levels, however, are not well
known.

The range for average recruitment gives some indica-
tion of the variability of the stock and its sensitivity to
various environmental factors. Recruitment rates range
from quite stable, as in the case of cod, where observed
recruitment values have fluctuated by no more than a
factor between 2 and 3, to those of haddock, where the
ratio reaches almost 2,700 to 1. It should be noted that
the range for haddock during times of good population
size is considerably less, roughly 20 to i, and that the
very high variability mentioned above reflects the fact
that a period of very low recruitment and spawning stock
size was included. Not only was recruitment low when
spawning stock size was low, but it was also more
variable (1,200 to 1).9 The degree of variability is impor-
tant when one considers that at present certain fisheries
count almost entirely on production from entering vear
classes. The more variable the year class, the greater the
uncertainty in the size of a fishable population at a given
time when it is made up of very few year classes.

5) Maturity.

The table shows age at the onset of maturity, and the
size at maturity. This does relate somewhat to the effects
of harvesting at younger ages. Obviously when
harvesting is done prior to maturity, a lower rate of


years Illex has been extremely abundant relative to
numbers observed earlier (Lange and Sissenwine, in
press).°° It is not known how long these high levels will
continue, but it would certainly be expected that spawn-
ing would eventually result in lower stock sizes as ob-
served previously. Illex is a wide ranging species from
North Carolina to Newfoundland with extensive
fisheries in Canadian waters. The extent to which
fisheries in these areas may affect abundance in the
Northeastern United States is not known.

Bluefish

Bluefish is a swift-swimming migratory pelagic species
that is found in loosely aggregated feeding schools both
inshore and offshore. Present knowledge of the distribu-
tion and abundance of bluefish is largely dependent on
nearshore recreational and commercial catches with only
supplemental data provided by bottom trawl catches of
research vessels. Most information is. therefore, limited
to the period bluefish spend in coastal and estuarine
waters. However, there is evidence that their distribu-
tion extends farther out on the continental shelf than is
generally believed, as indicated by the absence of both
large and small individuals during winter in South
Atlantic waters and by the sporadic catches made by
offshore otter trawlers (Wilk 1977).

Bluefish is one of the most important recreationally-
fished species for both food and sport. far exceeding the
commercial catches. The North Atlantic and Middle
Atlantic anglers’ catch was estimated at 16,765 T in 1960
(Clark 1962). It rose to 35,932 T in 1965 (Duel and Clark
1968) and to 45,305 T in 1970 (Duel 1973). The commer-
cial catch range (1950-1970) for the New York Bight was
between 90 and 1,220 T per year with an average
value of 635 T per year. For the period 1973-1975, com-
mercial landings increased to over 2,000 T per year.
Throughout the 1970's. research vessels have frequently
caught bluefish in offshore waters of the Middle Atlantic
and Georges Bank. The 1976-1978 average stratified
mean weight per tow is 26° larger than the 1967-1969
average value. It has been observed that the age com-
position of the catches is also quite robust, with ages 4
and older being well represented. This would indicate
that the condition of the stock is relatively stable, i.e.,
not dependent on one or two single year classes for con-
tinued recruitment.*!

Tilefish

Bigelow and Schroeder (1953) estimated a potential
sustainable vield of 1,000 to 1,500 T per year for tilefish
off Southern New England, New York, and New Jersey,
based on fishing reports of the 1900’s. Landings since
1915 reveal that the harvest has fluctuated considerably.
but it is difficult to translate this information into terms
of relative abundance because market conditions have
tended to dictate the level of landings more than abun-
dance. Since the all-time high in 1916 of 4,500 T (when
the U.S. Bureau of Fisheries first campaigned to
promote a food fishery for tilefish), landings have fluc-

tuated greatly, reaching a low of 32 T as recently as 1968.
In 1977 about 2,000 T were reported; this increase was
due largely to a rejuvenation of longlining out of New
Jersey ports. Large party boats have contributed to a
steady increase in the recreational fishery since 1969.
However, recreational catch remains small relative to
the commercial catch (Freeman and Turner 1977).
Catches of tilefish in research surveys have been com-
pletely lacking in most years and extremely small in
others, due to the habitat of the species which renders
capture unlikely.

Total Finfish and Squid

Total finfish and squid refers to the biomass of ail
species with the exception of invertebrates other than
squid, and also large pelagics (swordfish, sharks other
than dogfishes, tunas) and certain other fishes such as
menhaden, American eel, and white perch, which enter
bottom trawl catches only infrequently. The decline in
total biomass during the 1960’s and early 1970's to an all-
time low in 1975 was the strongest evidence of the
extremely high overall fishing mortality generated by the
distant-water fleets (Clark and Brown 1977, 1979). Since
1975, the resource has been increasing; present stock size
is estimated to have approximately doubled the 1976-
1978 average by weight. A large share of the increase is
due to squid and most recently to herring and mackerel.
The overall biomass is now approaching the levels that
existed prior to the distant-water fleet fishing in the ear-
ly 1960’s.*? .

DESCRIPTION OF TABLE

In the examination and interpretation of the status of
fishery resources, it is important to consider some basic
parameters of the populations and the potential of these
populations for interrelationships and interactions in the
ecosystem. We are attempting to do this by outlining the
state of our knowledge for a large number of species in
the accompanying tables. The table headings outline
these key characteristics and a brief discussion of these
characteristics follows.

1) Geographical range and stock structure.

The range of a fish population and the extent that it
exceeds the boundary of a management unit have impor-
tant implications for fisheries management. For exam-
ple, management requirements are quite different for
Loligo squid, which ranges only as far north as the edges
of Georges Bank, than for Illex squid, which moves to the
area off Newfoundland.

Consideration of stocks within the area breakdowns is
also useful information. The term “stock” is a very
nebulous one in the literature of biology. It basically im-
plies that there is a group that has a high degree of in-
tegrity in its breeding population and exhibits similar
patterns of growth and mortality rates throughout its
range. It does not imply that there is no intermixing.
Intermixing must occur to at least some degree or else


Table 3. cont'd

Geographic ranges
stock structure

Growth

Age range in
Fished populations

Recruitment

Maturity

LOL 1G0

From New Brunswick
to Georgia

1) Main fisnable stock

winters offsnore MA
Species south of YC
gues tionable

ILLEX

From Sreenlanc, Labracor,
and Newfours!. to FL
Stock structure un-
certain, sone appear

to migrate t)
summer conc. off
Newfounal; some surmer
on G8-GM

From ‘ova
Florica
Mainly founa at
ecge of shelf

Scotia co

Total FINFESH and SQUID

NW Atiant
Primarily offsnore,
GM, GB, SNE, MA

1.01.5 em/month

Few fisn found over
2 yrs

Max. age = 3 yrs
Max. lengtn = 40 cm

Faster growing than
Toligo

snorter ‘ived

2 cm/mo

Few fish found over

vax, age = 2 yrs
Nax. length = 40 cm

Fast growing

Max. age = 14 yrs
Paar

vax. Yength = 118 on

Slow growth rate

CAL J not aventavie

Max. age = 40-50 yrs
Max. length = 125

AA

6 m0 - 2 yrs

1 yr olds predominate
catch

No availaple data

On overall basis the
bulk of the yields
are taken of animals
5 yes of age

70% decline in
pre-recruit
individuals
(autumn 1978)

(5-6 mos)

Ratio is 17-1 for
1969-1974

Improved over last few
years, pre-recruits
for 1978 was second
hignest in time series.

(5-12 cm)

Ratio is 5.46-1 for 1968-
1978; orobably minimal due
to snort time series.

No available data

Ho available data

On the average recruit-
ment probably occurs at
age 2

Spawners die

afterwards so age at
maturity is about equal
to maximum age of indi-
vidual

Spawns May-Sep inshore

Same as oligo
Assumed: spawns Jec-Jul

in deep water of snore
areas.

Mature at age 2-5

Spawns May-Jun

Age of Ist maturity between
6-13 yrs

Soawn from Mar-Sep

Not available.

(cont'd)


Natural Fishing

Mortality Mortality Abundance MSY

SCUP (cont. )

Current data Rank 4 Minimum sustainable Denersal

not available

BUTTERFISH {cont.)
M=0.3 F increased from
21 in 1968 to
87 in 1974 ana
had dropped since
then due to the
reduction of the
foreign fishing

SPINY DOGFISH cont. }

Low be-
cause ccq-
fish nave
few satural
enemies ana
abundance re-
mains high
despite ‘ow
reproductive
rate

Not known

ANGLER (GOOSEFISH) .,cont

Not known Not known

9

POUT (cont. 3

Not known Not known

NORTHERN SHRIMP (cont.

M=0.25 Average of agorox
Appear to 1.5 during 1973-
increase 1977
significantly

after ‘st

hatching

Historical fluctuations in oopulations size
Dramatic reduction from 1960-1970. increased
landings since 1970 indicates resurgence,
however 1978 survey index is 36> less than
1967-1978 average.

Rank 3

Autumn surveys ingicate 20° decline from
1967-1374

Minimum biomass 1969-1973 = 61,000 7
1976 stock size - 22,000 T, lowest ob-
served for 1968-1976 period

1976 survey index is 15 less than 1967-
1978 average but still in MSY range

Rank 4

Range of biomass: from 150,000-225,000
witn ~ 20,000 T/yr catch since 1972
1978 survey index snows no significant
cnange from 1967-1978 average

Rank &
18,209 T standing crop estima
1968-7974 cata

1978 survey index 1s 37
1967-1978 average

yreater

cnan

Rank +

Jeclines in survey abuncance 2f 30°. from SNE
area 4 33°. S3 from 1963-1974

Yowever, 1978 index ‘s 13% greater tnen 196
378 average anc ‘andings nave increased
since 1978.

Rank 2
4as declined over 99° since ‘ate 1960's
ana currently remains at very sepressec
tevel

&

2
Ss

yield estimated at
15,900 7

Max. caten at Fy 1 is

18,500-21,500 T depend-
fag on age at entry
into isnery

Not <newn

Not available

lot known

Extensive seasonal migrations from
Sasnore summer sounds to offshore
winter crounds

Lotigo offshore; mixed ground?
inshore

Pelagic © cemersai
Move offsnore in late autumn ane
solmewhat south “nsnore migration

in Apr

Pelagic !Seni-demersa}

Soawn offshore in winter, begin
southward migration in Oct, return
nortn in ‘ate scring

ten cauent and sscarded tn summer

Jerersal

Sonen

estons have causes
in commer sue

No evidence 2% signt?icant staration

2) eestribution

Seasonai

20 secur

Jemersa

vals nove 19 ©
winter to scawn - va"
Found 17 seecer aaters

i Femais
1fsnere

(cont'd!


ment of several very good year classes (Anderson and
Paciorkowski. in press; Anderson 1979). The existence of
stock recruitment relationships is not clearly evident,
but it is probable that spawning stocks measurably
smaller than in the early 1960’s’ stocks would produce
fewer good year classes and more poor ones. There was a
considerable restriction of distant-water fleet fishing
during the late 1970’s. The 1978 year class appears to be
the largest in the past few years and will accelerate the
rebuilding of the stock. The spawning stock can be
expected to improve both in 1980 and 1981 based on en-
try of this vear class.!° This should bring the mackerel
spawning stock significantly above the minimal levels
observed at present, if harvest is maintained at the
moderate levels of recent years. Restricted fishing in
1980 may not only increase the spawning potential, but
should also increase yield per recruit.!*

Redfish

The redfish stock is characterized by many year
cl and very late recruitment to the fishery (Kelly
and Wolf 1959: Mayo, in press).'* In the Gulf of Maine
the stock size is considerably lower than in earlier vears.
The fishery has become increasingly concentrated on a
single vear class (1971), compared to previous years in
which individuals 20 to 30 years old have comprised
significant portions of the catch. The 1971 year class is
the only strong year class since 1963. It has now fully
recruited to the fishery with apparently no significant
recruitment following. Thus, to prevent further decline
requires harvesting only very small catches compared to
the earlier ones. which in part represented removals of
accumulated stock that had built up over the years when
fishing mortality was low. There are further indications
that the redfish stock consists of separate groups or
“pockets”: the fleet fishing a given area to low abun-
dance. and then moving to another pocket. Presently, it
appears that all “pockets” in the Gulf of Maine have
been reduced in abundance (Mavo, in press).

Yellowtail Flounder

Yellowtail flounder stocks have been studied most
extensively on Georges Bank and Southern New
England; less is known about the Cape Cod and New
York-Middle Atlantic area (Royce et al. 1959; Lux 1969;
Sissenwine 1977).!"'8'9 The Cape Cod stock has been
fished steadily for many years and appears to be main-
taining itself at its current modest level, although
recorded commercial catch-per-day is less than it was in
the late 1960’s.!" The Georges Bank stock entered 1979 at
very low levels, having declined considerably from the
middle 1960's.'*'* It would take several good year classes
fished only moderately to rebuild this population. The
Southern New England stock supported large yellowtail
catches during the 1940’s and again during the 1960's.
Catches were low in the 1950’s, as they have been recent-
ly. Pre-recruit indices indicated that these very low pop-
ulations would increase in 1979; commercial fishery data
confirm this.‘* The extent to which these recruits to the

fishery will accumulate in the spawning stock remains to
be seen. Commercial catch-per-day just prior to 1979
was quite low relative to earlier years. The present
spawning stock level of yellowtail flounder may be low
enough so that even with increasingly favorable en-
vironmental conditions, which seem to be cccurring in
Southern New England, a lower frequency of good year
classes can be expected than with a larger spawning
stock. Middle Atlantic catches and stock appear lower
than they were in the early 1970’s.

Winter Flounder

Winter flounder are distributed along the coast and
out onto Georges Bank. They are fairly sedentary and
there appear to be local populations along the coast.
There does not seem to be an appreciable movement
from Georges Bank to the inshore grounds.” Winter
flounder in general appear to have been somewhat lower
in abundance in the early 1970’s than in the 1960's,
possibly as a result of by-catch in the heavy offshore
fishery.” Stock sizes in the 1970’s, particularly on
Georges Bank, have increased to about early 1960's
levels. The commercial catch has also increased.

Summer Flounder

Summer flounder are found from Cape Hatteras to
Cape Cod with the center of abundance in the Middle-
Atlantic area. Populations south of Cape Hatteras may
be distinct from those to the north (Wilk and Smith
1980). Commercial landings were high in the late 1950's
and then declined throughout the 1960’s. Summer
flounders were subjected to the general increased fishing
mortality in the mixed offshore fishery of the distant
water fleet: with reduction of this mortality, U.S.
catches have increased. Survey cruise abundance indices
indicate increased abundance in the 1970’s compared
with the 1960’s.?!

American Plaice

American plaice are primarily found in the deeper
waters of the Gulf of Maine. They are also located on the
Scotian Shelf and are more important to the fisheries
there than off the U.S. coast. American plaice appears to
be a sedentary species; there is probably little mixture
between areas. Populations appeared to decline in the
latter 1960's and early 1970's and have since increased to
early 1960 levels. Commerical catch is now higher than
in the early 1960's,?°

Windowpane Flounder

Windowpane flounder occur primarily in the Georges
Bank and Southern New England areas. It has
traditionally been a by-catch species but recently, com-
mercial landings have increased. primarily on Georges
Bank. Only the very largest individuals of this species
are landed for food; others have been discarded or used
for industrial purposes. On Georges Bank, the survey in-
dices have been significantly higher during the 1970's
than in the 1960's. The Southern New England indices.


1978 Total Catch (MT) North and Middle Atlantic Regions as shown in Fig. 1

Atlantic Cod
Haddock

Pollock

Silver Hake

Red Hake

White Hake
Atlantic Mackerel
Redfish

Yellowtail Flounder
dinter Flounder
Summer Flounder
American Plaice
Windowpane Flounder
Witch Flounder
Atlantic Herring
River Herring
Black Sea Bass
Skates

Scup

Butterfish

Dogfish

Angler (Goosefish)
Ocean Pout
Northern Shrimp
Loligo

Illex

Bluefish

Tilefish

Table 1

18

us,

39,020
16,695
17,542
23,151
2,192
3,818
1,604
13,991
11,454
12 ,246
8,451
9,511
1,824
3,520
50,516
5,789
2,112
1,595
9,413
3,664
1,192
1,808
330

4
1,476
385
3,751
3,413

Foreign

26,495
10,821
4,754
14,475
2,155
195
370
170

59

64

12

209

0

18

585

32

0

226

2
1,236
558

39

0

0
4,777
21,458
0

1

Total

65,515
27,516
22,296
37 ,626
4,347
4,013
1,974
14,161
11,513
12,310
8,463
9,720
1,824
3,538
51,101
5,821
2,112
1,821
9,415
4,900
1,750
1,847

330

6,253
21,843
3,751
3,414


Table 3. cont’d

Geographical range:
stock structure

Growth

Age range in
Fished populations

Recruitment

Maturity

From Gulf St. Lawn,
to So. Carolina

‘ITCH FLOUNDER

From Newfcund, to Cape
Hatteras

3} SM-area of conc

2) Nova Scotia

Spawning areas are GM,
Nova Scotia, coastal ME
They overwinter primarily
south of CC

ATLANTIC HERING

From solar ice in Green-
land and Labrador to
Cape Hatteras

1) 6B
2} Nova Scotia
3) Coastal ME

Laraest individuals found
on GB

Max. age = not known
Max. length = 38 cm

Slow growth rate 18-20
yrs old at 60 cm

i 4 not known

Max. age = not known
Vax. length = 63 cm

le
a 34.5 0.36
N. Scotia. 39.0 9,179
Coastal ME

Western 38.1 9.335
Eastern 38.9 9.277

Max. age = 18 yrs
Max. length = 43.5 om

BLUEBACK HERRING

RIVER SERRING, ALEWIFE
From ova Scotia to
FL + Sluesack

rom ‘iew?. to NC =
Slewite

1) Major populations
in civers Chesapeake

Spawning runs also found
along coast.

SLACK SEA BASS

From CC to Cape
Canaveral

cae

1) North of
Hatteras
2) South of
Hatteras

Several soecies;

sq 4 Little Skates,
Thorny Skates impor-
nt in Fisheries
tock studies but
ncentration

Alewife
<= 634

Le

32.5

Max. age = 11 yrs
Max. length = 33 cn

Bluebacks slower and
grow to a smaller
size

« 3.088
Les 62.5

Max. age = 20 yrs
Max. length = 61 cm

2-19 cm/yr for Ist & 3rd yr
2-3 cmvyr after age 5

2. Skate L. Skate
ee 2 382
Les 32. 52.7
Max. age:

Not known 8 yrs
Max. Yengtn

107 cn

Mean age of individuals
decreased from about
4-5 yrs (1963-1970)
to 3 yrs (1971) to 2
yrs (1972)

5 yr olds most abundant
in 1975 landings

Not known.

12 yr
The very strong 1970 year
class provided 73% of

catch from 1973 to 1976.

1-9 yr
Average age of alewives
has declined in recent
yrs.

Mewife dominant ages
in catch are 4, 5.86.

2-12 yr
Only available litera-
ture states that in
1946 oopulations was
dominated by age

4-7 fish.

2-2

Catch is dominated ay
age 4-8 yr fish

Enter fishery at aoprox-

imately 4 yrs

Not available

Age 1 juvenile fishery
Age 3 adult Fishery

Ratio is 10.6-1 for
these stocks 1965-77.
Ratio is t31-1 (Atianto

Scandia) 1965-77

Alewife

Becoming mere deoendent
on a single year class
recruited at time of
Ist spawning.

No available data

Little Skate oartial
recruitment at 2 yr

No available data for
other species

Mature at age 2-4.

Spawns on GB
and Nantucket Shoals

and South Apr-Jun.

Peaks in Yay.

Beains again in late fall.

Spawns from CC to
Selaware Bay in late
soring - summer.
Peaks Jul-Aug.

Mature at age 2-4
Spawns Sep-Nov on GB and
Nantucket Shoals - Sd GM,
smaller spawning stock
along eastern coast of ME

Alewife mature between
3-8 yrs.

Blueback

o's spawn 3-4 yrs
9's spawn 4-5 yrs
Repeat spawning 4-5
times.

Spawning:

Alewife - spring
Bluedack - late soring

Hermaohrodi tic
Begins life as 2,

trans forms into'o!
Mature between 2-3 yrs
Larvae caught Jun-Nov

Skates mean age

ir spawnings with
peak periods all soecies.

Peaks for Little Skate
Nov-Jan and Jun-Jui

Provably about 30 24g
cases per ir most snecies

(cont'd)


Summary and Conclusions........... eee eee e eee deen eee n eee eee 10

Acknowledgements .......... ences cece eee eens an ec ee nena ll
Footnotes ...... 0... cece cece cece ence eens Pence nett e nee eeee ll
Literature Cited ....... Leeeae bene e ence ees Lecce cece eee eee eens 12
Figures .... 2.0... eee eee eee eee e eee ees aS 14
1 Major geographical areas off the Northeast coast of the United States. 14
2 Relative percentages of recreational, foreign and U.S. commercial catch
to the total catch for each species in the year 1970 ......... ec see eee eeee 15
3 U.S. and foreign commercial catch values -
(mean total annual catch 1969-1978)... cece eect eee eee 16
4 Salt water angling effort: 1960, 1965 and 1970 ...... cece eee ee eee eee WwW
Tables... 00.00... cece ee eee Leen nee e eee eee an 18
1 1978 total catch (MT) North and Middle Atlantic Regions as shown
in Fig, L wee. eee eee . seen wee eee eee eee eeeee beeen eee 18

2 Annual U.S. and foreign. commercial landings for major species
1969-1978 for areas shown in Fig. 2
3 Resource summary table



the fishery management practices pursued, but they will
continue to be a major feature of fishery resources now as
in the past.

ACKNOWLEDGEMENTS

The authors wish to thank the members of the Northeast
Fishery Management Task Force Subcommittee on Status of
the Resources: V. C. Anthony, D. Arnold, and J. Mason for
their contribution to developing the areas to be covered in this
document. M. Aleon and R. R. Lewis of the Northeast Fisheries
Center assisted in the preparation of materials for this docu-
ment. E. D. Anderson and M. P. Sissenwine provided critical
editorial assistance. The NEFC Assessment Division staff
critiqued particular species statements.

FOOTNOTES

1. Common names as in Bailey ed., 1970.

2. Serchuk, F. M., P. W. Wood, and B. E. Brown. 1978. Sum-
mary and review of the 1978 assessment and status of the Gulf
of Maine and Georges Bank cod stocks. Northeast Fisheries
Center, Woods Hole Laboratory, National Marine Fisheries
Serv., NOAA, Woods Hole Lab. Ref. Doc. 78-11, (mimeo.) 18 p.

3. Serchuk, F. M., and P. W. Wood. 1979. Review and status of
the Southern New England-Middle Atlantic cod, Gadus
morhua, populations. Northeast Fisheries Center, Woods Hole
Laboratory, National Marine Fisheries Serv., NOAA, Woods
Hole Lab. Ref. Doc. 79-37, (mimeo.) 77 p.

4. Serchuk, F. M., P. Wood. S. H. Clark, and B. E. Brown.
1977. Analysis of the Georges Bank and Gulf of Maine cod
stocks. Northeast Fisheries Center, Woods Hole Laboratory,
National Marine Fisheries Serv. NOAA, Woods Hole Lab.
Ref. Doc. 77-24, \Mimeo) 26 p

5. Serchuk, F. M., P. W. Wood, and B. E. Brown. 1978. Atlan-
tic cod (Gadus morhua): assessment and status of the Georges
Bank and Gulf of Maine stocks, January 1978. Northeast
Fisheries Center, Woods Hole Laboratory, National Marine
Fisheries Serv.. NOAA, Woods Hole Lab. Ref. Doc. 78-03,
(mimeo.) 25 p.

6. Serchuk, F. M., P. W. Wood, R. Lewis, J. A. Penttila, and
B. E. Brown. 1979. Status of the Georges Bank and Gulf of
Maine cod stocks, February 1979. Northeast Fisheries Center,
Woods Hole Laboratory, National Marine Fisheries Serv.,
NOAA, Woods Hole Lab. Ref. Doc. 79-10, (mimeo) 32 p.

7. Hennemuth, R. C. 1969. Status of the Georges Bank had-
dock fishery. Int. Comm. Northw. Atlant. Fish. Res. Doc.
69/90, (mimeo), 21 p.

8. Clark, S. H., and W. J. Overholtz. 1979. Review and assess-
ment of the Georges Bank and Gulf of Maine haddock fishery.
Northeast Fisheries Center, Woods Hole Laboratory, National
Marine Fisheries Center, Woods Hole Lab. Ref. Doc. 79-05,
(mimeo.) 68 p.

9. Hennemuth. R. C., J. E. Palmer, and B. E. Brown. 1979.
Recruitment distributions and their modality Part 1: descrip-
tion of recruitment on 18 selected fish stocks. Int. Cons.
Explor. Sea. C.M. 1979/H:37., (mimeo.) 24 p.

10. Clark. S. H., T. S. Burns, and B. P. Hayden. 1978. An
assessment of the Scotian Shelf, Gulf of Maine, and Georges
Bank pollock stock. Northeast Fisheries Center, Woods Hole
Laboratory, National Marine Fisheries Service. NOAA, Woods
Hoie Lad. Ref. Doc. 78-37, (mimeo.), 33 p.

11. Anderson, E. D., 1974. Comments on the delineations of
red and silver hake stocks in ICNAF Subareas 4 and Statistical

ll

Areas 6. Int. Comm. Northw. Atlant. Fish. Res. Doc. 74
(mimeo.), 7 p.

12. Anderson, E. D., and F. P. Almeida. 1979. Assessment of
the southern New England-Middle Atlantic red hake stock.
Northeast Fisheries Center, Woods Hole Laboratory, National
Marine Fisheries Service, NOAA, Woods Hole Lab. Ref. Doc.
No. 79-06. (mimeo.), 27 p.

13. Almeida, F. P., E. D. Anderson, and H. A. Herring. 1979.
Status of the Georges Bank red hake stock in 1978. Northeast
Fisheries Center, Woods Hole Laboratory, National Marine
Fisheries Serv. NOAA, Woods Hole Lab. Ref. Doc. 79-01,
(mimeo.}, 21 p.

14. Clark, S. H., and B. P. Hayden. 1978. A review of the
current status of white hake (Urophycis tenuis) in the Georges
Bank/Gulf of Maine area. Northeast Fisheries Center, Woods
Hole Laboratory, National Marine Fisheries Serv., NOAA.
Woods Hole Lab. Ref. Doc. 78-29, (mimeo.), 7 p.

15. Anderson, E. D., and W. J. Overholtz. 1979. Status of the
Northwest Atlantic mackerel stock-1979. Northeast Fisheries
Center, Woods Hole Laboratory, National Marine Fisheri
Serv., NOAA, Woods Hole Lab. Ref. Doc. 7: i

16. Davis, W. S., and C. C. Taylor. 1957. Optimum exploita-
tion of Gulf of Maine redfish as indicated by a simple popula

tion model. Int. Comm. Northw. Atlant. Fish. Int. Coun

Explor. Sea., Food Agri. Org.. Joint Sci. Meet., Lisbon. Port

(mimeo.), 31 p.

17. Brown, B. E., and R. C. Hennemuth. 1971. Assessment cf
the yellowtail flounder in Subarea 5. Inter. Comm. Northw

Atlant. Fish. Res. Doc. 71/14. (mimeo.}, 57 p.

18. Sissenwine, M. P.. B. E. Brown, M. M. McBride. -
Yellowtail flounder ( Limanda ferruginea): status of the stocks.
January 1978. Northeast Fisheries Center. Woods Hue
Laboratory, National Marine Fisheries Serv.. NOAA, Woods
Hole Lab. Ref. Doc. 78-02, (mimeo.). 25 p.

19. McBride, M. M., and M. P. Sissenwine. i979. Yellowtail
flounder (Limanda ferruginea): status of the stocks, February
1979. Northeast Fisheries Center, Woods Hole Laboratory,
National Marine Fisheries Serv.. NOAA. Woods Hole La»
Ref. Doc. 79-06, (mimeo.), 17 p.

20. Lange, A. M. T.. and F. E. Lux. 1978. Review of the other
flounder stocks (winter flounder, American plaice. witch
flounder, and windowpane flounder) off the Northeast United
States, August 1978. Northeast Fisheries Center. Woods Hole
Laboratory, National Marine Fisheries Serv., NOAA. Woods
Hole Lab. Ref. Doc. 78-44. (mimeo.), 45 p.

21. Henderson, E. M. 1979. Summer flounder ( Paralichthys
dentatus) in the Northwest Atlantic. Northeast Fisheries
Center, Woods Hole Laboratory, National Marine Fisheries
Serv., NOAA, Woods Hole Lab. Ref. Doc. 79-31, (mimeo.). 31 p.

22. Johnson, H. B., B. F. Holland. and M. W. Street. 1!
Biology and management of Mid-Atlantic anadromous fishes
under extended jurisdiction. Annual Rept. Anadromous Fish
Project. Va. Inst. Mar. Sci., Gloucester Point, Va.

23. Mayo, R. 1979. Northeast Fisheries Center, Woods Hole
Laboratory, National Marine Fisheries Serv., NOAA. Woods
Hole, MA. Pers. Comm. Oct. 1979.

24. Waring, G. T. 1980. 4 preliminary stock assessment of the
little skate, Raja erinacea, in the Northwest Atlantic. MA
thesis. Bridgewater State College. 122 p. (unpublished)

25. Waring, G. T., 1979. Status of the Northwest Atiantic
butterfish stock. July 1979. Northeast Fisheries Center, Woods
Hole Laboratory, National Marine Fisheries Serv.. NOAA.
Woods Hole Lab. Ref. Doc. 79-33. (mimeo.). 12 p

26. Grosslein. M. D. 1974. A first approximation of M
spiny dogfish in Subareas 5 & 6 and Division 4X. Int
Northw. Atlant. Fish. Res. Doc. 74 30. Ser. No. 3177
Lp.

00,



International Commission Northwest Atlantic Fisheries. 1973.
Proceedings of the spectal commission meeting January 1973
and the 23rd Annual Meeting June 1973. Int. Comm. Northw.
Atlant. Fish., Halifax, N.S.. Can

International Commission Northwest Atlantic Fisheries.
1974a. Statistical Bull. Vol. 22. Int. Comm. Northw. Atlant.
Fish.. Halifax. N.S.. Can.

International Commission Northwest Atlantic Fisheries.
1974b. Proceedings of the Third Special Meeting October 1973.
Int. Comm. Northw. Atlant. Fish.. Halifax, N.S., Can.

International Commission Northwest Atlantic Fisheries. 1975.
Statistical Bulletin Vol. 23. Int. Comm. Northw. Atlant. Fish.,
Halitax, N.S., Can.

Jensen, A. C. 1965. Life history of the spiny dogfish. Fish. Bull.
CLS., 65(3): 527-354.

kelly, G. S., and R. 5. Wolf. 1959. Age and growth of the red-
fish, Sebastes marinus, in the Gulf of Maine. Fish. Bull., U.S.,
69: 1-31.

Kendall, A.W. 1977. Biological and fisheries data on black sea
bass. Centropristis striata (Linnaeus), Sandy Hook Lab.,
Northeast Fish. Ctr., Nat. Mar. Fish. Serv., NOAA Tech. Ser
Rept. 7,29p

Kendall, A. W.. and L. P. Mercer. In press. Black sea bass (in
Ecology of Middle Atlantic Bight fish and shellfish) MESA
New York Bight Atlas Monograph 15. Albany. NY, New York
Sea Grant Institute.

Lange. A. M. T.. and M. P. Sissenwine. In press. Biological
considerations relevant to the management squid (Loligo
pealie and Illex illecebrosus) of the Northwest Atlantic. NOAA
Technical Report

Lux, F. E. 1969. Landings per unit of effort, age composition,
and total mortality of yellowtail flounder ( Limanda ferruginea
Storer) }. off New England. Int. Comm. Northw. Atlant. Fish.
Res. Bull. (6): 47-52.

R. M. In press. An assessment of the Gulf of Maine red-
fis bastes marinus L. Int. Comm. Northw. Atlant. Fish.
Res. Bull.

Morse. W. W. 1978. Biological and fisheries data on scup.
Stenotomus chrysops (Linnaeus). Sandy Hook Lab., Northeast

13

Fish. Ctr., Nat. Mar. Fish. Serv. VOAA Tech. Ser. Rept. 14:
41 p.

Murawski, S. A.. D. G. Frank. and S. Chang. 1978. Biological
and fisheries data on buttertish. Peprilus triacanthus «Peck?
Sandy Hook Lab, Northeast Fish. Ctr.. Nat. Mar. Fish. Serv
NOAA Tech. Ser. Rept. 8. 39 p.

Murawski, S. and G. T. Waring. 1979. A population assess
ment of butterfish. Peprilus triacanthus, in the Northwestern
Atlantic Ocean. Trans. of the Amer. Fish. Soc. Vol. 108, No. 5.
Sept. 1979. pp. 427-439.

Royce. W. F., R. J. Buller, and E. D. Premetz. 1959. Decline of
the yellowtail flounder ( Limanda ferruginea) otf New England.
Fish. Bull, U.S. 59: 169-267.

Sette, O. E. 1950. Biology of the Atlantic mackerel (Scomher
scombrus) of North America. Part 2. Migrations and habits.
Fish. Bull. U.S, 51(49): 251-358.

Sheehy, D. J.. M. P. Sissenwine. and S. B. Saila. 1974. Ocean
pout parasites. Mar. Fish. Rev. 36(5): 29-33

Sissenwine. M. P. 1977.
model of the southern
Limanda ferruginea, fishery.

A compartmentaiized ulation
vew England yellowtail

sh. Bull. US.

an adequate foundation for op-

Sissenwine, M. P. 1978. Is
timum yield? Fisheries 34

24-
Von Bertalan! L. 1938. A quantitative theory of organic
growth ‘inquiries on growth laws II). Human Bioingy i: ISt-
128.

Wigley, R. L. 1973. Fishery for northern shrimp in the Gui o:
Maine. Mar. Fish. Rev. 35(3-4): 9-14.

Wilk, S. J. 1977. Biological and fisheries data on bluefish.
Pomatomus sairatrix (Linnaeus). Sandy Hook Lab.. Northeast
Fish. Cur., Nat. Mar. Fish. Serv.. NOAA Tech. Ser. Rep. 11
Sep.

Wilk, S.J.. W.G. Smith, D.E. Ralph, and J. Sibunka 1:80. The
population structure of summer flounder between N.Y. and
Florida based on linear discriminant analysis. Trans. of *)-
Amer. Fish. Sov. 10903) 1

Wise, J. 1962. Cod groups in the New England area. Fish. Bu
U.S. 63: 189-203.



TABLE OF CONTENTS

Introduction .....
Synopses of Species

Atlantic Cod. 6... cece eee nee eee eee eeee 2
Haddock ....
Pollock .....
Silver Hake .
Red Hake.... bees seen beeen’
White Hake 2... cece eee eee eee terete teen e eee tees

Redfish .........
Yellowtail Flounder .
Winter Flounder. ,
Summer Flounder .
American Plaice....
Windowpane Flounder
Witch Flounder 2.0... ccc cece eee eee e eee nee 5
Atlantic Herring .
River Herring...
Black Seabass
Skates ......
Scup .......
Butterfisn 00... eect een eet eee t ete
Spiny Dogfish, 0... cere eee eet eee e eee
Angler-goosefish ,
Ocean Pout ....
Northern Shrimp
Loligo Squid... .
Illex Squid ., .

Bluefish 0s ooo sss ce cess esse secesseseesesetrersenenegeee]

Tilefisn cece cee nent eet e nen eee nee 7

Total Finfish and Squid 26.0... ice eee eee eee eee 7
Description of Table ....... 00... cece cece eee e eee e nee e teens 7

Geographical Range and Stock Structure

Growth

Age Range in Fished Populations
Recruitment ............05
Maturity ...
Natural Mortality .
Fishing Mortality .
Abundance .... 6. eee eee

Maximum Sustainable Yield .......... 0. c cece cece eee ences 10
By-catch 2... eee eee eet eens 10



Table 3. cont'd

Geograohical range; age range in
stock structure Growth Fished populations Recrui tment Maturity
MACKEREL
From Block Is., Labrador, <#0,257 2-64 yr Mean age: 3 (70%) First spawn 2-3 yr (50%
to Beaufort, NC Lesat a3 mature at age 2).
At this time, 2 principal Ratio 18.2-1 for 1962-
Considered as one Max. age = 18-20 yr year classes in fishery: 1978. Spawn in NY Bight and GB
Stock for management Max. length = 56 cn 1973 and 1974. Spawn on Western GM and CC Bay
on oresent evidence. in spring and early
1978 is largest year class summer. Peak May-June.
(Winter concentrations to enter fisnery since Stock also spawns in Gulf
off US MA/So. Atlant. 1969. St. Lawr.

coast. Summer GM, GB,

Max egg production: age 4
Gulf St. Lawr.)

REDFISH
mW. Greenland to x 20.108 6225+ yr Since 1963, only 1971 year Mature at age 3-9
wew Jersey (2 species) —L»=37.80 class shows above-average (viviparous).
usually 12-25 age range. strength. Other dominant
1) SM is range of 1976 introduced ace 3's year classes: 1953, 1963, Spawn on Scotian Shelf
_tentelia off US. Max. age = >50 yr into fishery from 1971 1971. and Central GM
Botn S. rentella Max. length = 45-50 cn yezr class. Peak late June to early

arinus Age at Ist recruitment = 5. July.
found further north.

OWTAIL
From South coast of «9,335 2-124 yr SNE offers more favorable First spawn 2-3 yrs.
Labrador to Chesa~ L==50.0 cm in 1977 temo. regime.
peake Bay ages 2-3 dominated Mean age 2 yrs improving Spawns March thru
catches in fishery. recruitment in SNE August on Erowns,
)oM Max. age © 14+ yrs Prior to entrance of Ratio is 1.96-1 for GB Bank.
63 Max. length = 55 cm@ foreign fleets in 1963-1975. Max egg production: age 7
SNE latter 1960's ages Ratio is 11.5-1 for SNE
Ma 344 dominated catch. 1963-1975.
cc

From Labrador Ford-wal ford Growtn Ze1de ye 1977 SNE pre-recruit index Mature 2-3 yrs.
to Georgia Equation used: up_173% over 1974-76 average.

GB Cape $No. Cape $So.E. Mocal distribution 1977 GB pre-recruit index Occurs later in more
1) 68-59% <=.67 6978 ‘of catch would most likely shows improvement from 1976 northern waters.
2) SNE=13% les87.8  45.5cm 48.2 be in Ist half of this but is 61% down from 1975
3) GM-22% g * Faveraged range. peak. Spawns Apr thru June on G8
4) Local inshore sopu 1977 GM pre-recruit index

jations found Max. age = 12+ yrs is larger in 1963-1977
(o's are of total catch.) Max. length = 62 cm series.
SUMMER FLOUNDER
From CC to Cape « .209 2-7 yrs Recruitment begins at age Mean age = 3 yrs
yatteras La=92.24 Vor 2with full recruit-
Survey catches mostly ment at age 3 or 4. 50% mature at 35 cm.

1) 8 Max. age = 20 yrs 3 and 4 yr olds

Soawns on Nantucket Shoals
and south Sept-Apr in
north to south progress ion.
Early Sept for GM.

Max egg production: age 7.

SNE Max. length = 95 cm
MA

SMERICAN PLAL

From Laprador to Rather siow growtn rate Not available. Soawns south of Martna’s

of cC of shore from Vineyard March-cune.

New York a 3 not known Peaks Apr-May

“i Srarea of conc, Max, age = not known .
Max. length = 23 cm (cont'd)



PREFACE

This document is the result of studies originating within the North-
east Fishery Management Task Force. The Task Force, organized in 1979
by the New England and Mid-Atlantic Fishery Management Councils and
funded by the NMFS, seeks to promote discussion and dialogue on the
major issues of fishery management and to explore the effects of various
fishery management alternatives.

Composed of representatives from the fishing industry, Regional
Fishery Management Councils, federal and state agencies, academic in-
stitutions, and general public, the Task Force will operate in three phases.
The first phase will assemble background information for identifying and
analyzing management options. The second phase wil! examine this
background information to determine the data requirements, regulatory
measures, administrative procedures, and enforcement methods
associated with each management option. The third phase will critically
review the various options for application to specific fisheries, particularly
the Atlantic demersal finfish fishery.

This document is one of eight developed under Phase I operations,
all of which are being issued in the NOAA Technical Memorandum
NMFS-F/NEC series. This document and six others functionally serve as
appendixes to the eighth and leading document for Phase I operations—
“Overview Document of the Northeast Fishery Management Task Force,
Phase I.”

Jon A. Gibson, Coordinator
NOAA Technical Memorandum NMFS-F/NEC series


Table 3. cont'd

Natural Fishing By-catch/
Mortality Mortality Abundance “sy Distribution

WINDOWPANE (cont. }

No est- “ot known Qank 3 Not available. Spiny dogfish, Iittle skate,
imates Survey indices significantly nigner since silver nake, red hake, scud,
avail- 1972 (1963-1971) = 3.70. Since 1972 = duttertisn, yellowtail, suid,
able. 19.92 mean/tow, winter flounder

Life D 1

history Demersal

would indicate

Relatively sedentary found in aeecer
water in coldest montns snort annual
insnore-of fshore migration.

M=Q.2-0.3

WITCH FLOUNDER (cont.)

No est- Not known. Rank 3 Not available. Thorny skates, cod, naddock,silver
ima tes 1978 5M survey index is 9% greater than 1963- hake, collock, white hake, red-
avati= 1978 average; 1978 YS survey index is 37% Fish) Am. Olaice

able less than 1969-1978 average. Large *luctua-

tion is seen during this time series Demersal

nistory Rather staticnary
ouis directed fisner;
indicate Yo directed Fisnery.
3.10.2

cepeuves utearan ¢ . GM = 16,090 7
ATLANTIC RING (cont SNE, GB, MA
Age/Hortalicy 1.0 in 1973 Rank 2 125,000 T. Scotian Catches in purse-seines and oeia-
: 5 {edeoal Fe 0.55 in 1978 There was an 87% reduction in stock Shelf = 39,200 - qic trawis are revatively sure
3 91300083 An F of 9.6 on abundance by weiant from 1967 to 304.000 > ‘hen cauant in soring in sottom
3 914700135 long-term basis 1973. After 1974 abundance of G3 . trawl fishery, mixed crounaf. aiso
3 e038 will provide 95% nerring is not clear nowever caten pelagic taken
for avarane of yield per re- declined in 1976 and there was 3]- Delage
or eters cruit realized most no caten in 1977, Entry of a1 MSY propably less °
in nature poo. from an £ of 1.6. 1976 year class is rapidly increasing than sum of individuals Distribution aiffers by size % age
Seen seo Fy) ranges from abundance due to stock ‘nter- Soawn on GB, Jeffrey's wedge in
- BL et O38, actions. autuna then migrate to WY Sight area

ro Gverwinter. Miarate pace ‘n saeing

RIVER HERRING, ALEWIFE, ELUESACK HERRING (cons. 1

Annual mortality aank 4 23,000-28,000 7 Same as sea nercing. catenin
between 50% 8 602 Blueback appear tess abuncant than ale- soring soawning runs is relatively
1965-1969 wife in NY Bight. Alewife - virgin cure.
39% in 1975 Fish comprise greater oortion of Dopu- seta

Jation. Decline in stock abundance Pelagic

Spawning Fy since 1969. 1978 survey index is 11 Anacroncus. Suawns cn chesaeaxe
adults less than 1967-1978 average. Bay in dor on Nove Scotia in Jun.
die during Autumn spent on GB-SM area.
fresh water
onase.
SLACK SEA BASS (cont.)
Not known Not known gank 4 Not available Cemersal
Landings have declined steadily since
early 1960's from »20 million Tbs in Northern sooulations irate
1950's to >5 million Ibs in mid-i970's gasonaily inshore nortr in

1978 survey index is 42% Tess chan sorina offsnore south in autumn
1967-1978 average

‘ot known Rank + sot avaitable
Minimum biomass estimate 1963-1973;
little skate 82,000 7

Not known big skate 23.000 7

Cage Hatteras to GB spring surveys
orovide best estimate. 1978 survey
index is 25% greater than 1967-1978
average.

‘cont'd!

25


harvest is required to allow the same spawning potential
as when harvest begins at older ages. However, since in
most cases the number of eggs produced relates to the
weight of the fish and thus the age of the fish, there is, in
general, an increase in potential egg production with in-
creasing size. To get an indication of the meaning of this,
we calculate the age at which, under a nonfishing situa-
tion, the maximum egg production would occur for a
given year class. This is a product of the number at age
from mortality rate curves for the mature component of
the population, the weight at age (assumed proportional
to fecundity) from growth curves, and the fecundity at
weight relationships. The length of the spawning season
is also given. The implication of this, of course, is that
those stocks with small spawning areas and/or times
would be expected to have wider fluctuations due to en-
vironmental variations than stocks with broader spawn-
ing areas and longer spawning seasons. For certain
specialized stocks such as dogfish, which produce very
small numbers of young and spawn perhaps every other
year, such pertinent items are noted.

6) Natural mortality (M).

Natural mortality rates are one of the most difficult
parameters of fish populations to estimate. Many of the
values here are only approximations. They all apply to
fish of sizes which can be recruited into the fishery, and
larger. The higher the mortality rate the more rapidly
the fish die, and the more rapidly, at younger ages, one
would expect to harvest them. Low mortality rates imply
a stock that would maintain itself for a considerably
longer period of time. For example, at a mortality rate
point of 0.2 and no fishing, one would expect 18° of the
population at the beginning of the year to die of natural
causes over the year, whereas in a population where M =
0.4, 33° would be expected to die during the year. Since,
to a certain extent, harvesting replaces natural mortality
with fishing mortality, (by catching some fish that would
die naturally) the higher the natural mortality the more
fish that can be harvested in a given year. When this is
combined with growth, however, greater yields may
come over time from individuals with lower mortality
rates and an opportunity to accumulate more growth in
weight in the population prior to being harvested.

7) Fishing mortality.

Fax is a fishing mortality rate which would result in
the maximum possible yield being obtained from
harvesting a given cohort or year class. Fishing at the
F max level has been shown in a number of cases to result
in very low spawning stock sizes. Hence, an alternative
value F,, (Gulland and Boerma 1973) has been
recommended by ICNAF in its later years, by scientific
advisers to ICES, and by Canadian scientific com-
mittees after the 200-mile limit. This is a value less than
Fax which gives almost as much yield as one would
achieve by fishing at Fax but which results in a con-
siderably higher stock size and a much greater catch per
unit effort for individual vessels.

Frnex and F,., are given in the table when available, for
both conditional and optimal cases. The conditional case
assumes that the present age at entry into the fishery
will remain constant, and chooses the best fishing mor-
tality rate according to the definitions of Fmaz and Fy.;.
The other F values given refer to the overall maximum,
i.e., when age at entry into the fishery is included in the
maximizing procedure.

Finally, an estimate of current F is presented. Where F
is considerably above Fax and F).,, reductions in F will
give a higher yield per recruit, a larger spawning stock,
and in many cases an overall total increase in yield along
with a greater catch per unit of effort. Where it is con-
siderably below F,,.,, room for expansion is indicated.

8) Abundance.

This column lists the condition of the current stock
size relative to historic levels in terms of population size.
The information in the column is based on both fishery
and research vessel survey data.

A simple index was devised to suggest what confidence
we can place in estimates of population size trends. A
rating of 1 indicates that the relative change in popula-
tion size with time is considered by the assessment group
at the Northeast Fisheries Center, National Marine
Fisheries Service, NOAA, to be measured with con-
siderable precision. Ratings of 2 and 3 are considered
moderate or poor. while a rating of 4 indicates that the
information available gives only very modest improve-
ment over accepting the informationless state of
assuming the size to be within the historic range ot
observed values for the stocks. Our level of confidence is
influenced by the level of variability in the resource as
well as by our analytical methods; it is much easier to
describe large fluctuations in abundance than smaii
ones.

It should be noted that these are very difficult kinds of
ratings to make: they are, in a sense, gamblers’ hunches.
There is a great deal of knowledge about certain stocks.
and this may be adequate, depending upon the manage-
ment goal. On the other hand, even the most precise es-
timates of stock size possible do not pretend to estimate
the stock size exactly. Estimates at any moment can
only provide guidelines which adhered to over time can
help to achieve management goals. They cannot be
separated from management objectives but serve as
necessary numerical values for developing management
measures. The variance about any single point estimate
may be large but the study of trends and biologicai
characteristics provides significant information to make
assessment of the stocks a valid description of relative
conditions and projections of longer term results of par-
ticular harvest strategies.

The present condition of a stock relative to its historic
condition is the point about the assessment which is the
most valid and the most useful for decision making.
When stocks are abundant, they are fairly robust against
a very large number of socioeconomically oriented
management objectives; i.e., management goals can he


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(mimeo.). 9p.

28. Appolonio, B., and E. E. Dutton, Jr. 1969. The northern
shrimp (Pandalus borealis) in the Gulf of Maine. Completion
Rept. Com. Fish. Res. Development Proj. 3-12-R (mimeo.), 82 p.
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Maine Northern shrimp—current status and future outlook.
Northeast Fisheries Center, Woods Hole Laboratory, National
Marine Fisheries Serv.. NOAA, Woods Hole Lab. Ref. Doc. 79-
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30. Lange, A. M. T. 1979. Squid (Loligo pealei and Illex il-
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