-12-

Table 3. Variables used in two-group linear discriminant analysis
separating summer flounder, Paralichthys dentatus,

collected off New York-New Jersey (NY/NJ) and south of

Cape Hatteras (SNC) including resulting discriminant

coefficients.

Discriminant

Variable coefficient
Ventral eye width -0.29458
Body depth "0.18112
Posterior margin of dorsal eye -0.17239
Standard length -0.00121

Dorsal eye width -0.26484



-6-

Wilk et al. (1980) suggested that Cape Hatteras forms a zoogeographical
barrier resulting in reproductive isolation of summer flounder.

We were unable to examine adequately the hypothesis of multiple stocks in
the Middle Atlantic Bight. Smith (1973) identified concentrations of summer
flounder eggs off Long Island, Delaware-Virginia, and North Carolina.

However, distribution of summer flounder eggs and larvae was essentially
continuous throughout the Middle Atlantic Bight and apparent concentrations
may have been due to sampling variability.

A recent tagging study conducted off North Carolina revealed interesting
differences in movement patterns relative to previous summer flounder mark-
recapture experiments. No evidence of an offshore autumn migration was
obtained in the North Carolina experiment, while studies conducted off New
York (Poole, 1962), New Jersey (Murawski, 1970), and Southern New England (Lux
and Nichy, 1980) have consistently demonstrated an offshore movement to the
outer continental shelf during fall and a subsequent return to coastal
locations in spring. It should be noted that the number of recaptures in the
North Carolina study was low relative to previous summer flounder mark-
recapture experiments, possibly due to tag induced mortality (J. Gilliken},
pers. comm.). It is probable that summer flounder in the southern segment of
the range undertake less extensive migrations due to the relative proximity of
the continental shelf break and the less drastic temperature extremes
characteristic of more southerly latitudes.

Further work on summer flounder stock identification in the Middle
Atlantic Bight is clearly indicated to resolve current uncertainties. Further
comparisons of meristic and morphometric. characters collected throughout the
Middle Atlantic Bight should be made and coupled with concurrent electro-

phoretic and/or tagging experiments.



BHOlo

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NOAA Technical Memorandum NMFS-F/NEC- 18

This TM series is used for documentation and timely communication of
preliminary results, interim reports, or special purpose information; and
has not received complete formal review, editorial control, or detailed
editing.

Stock Discrimination

of Summer Flounder (Paralichthys dentatus)
in the Middle and South Atlantic Bights:

Results of a Workshop

Michael J. Fogartry’, Glenn DeLaney?, John W. Gillikin, Jr.3,
John C. Poole4, Daniel E. Ralphs, Paul G. Scarletté,
Ronal W. Smith’, and Stuart J. Wilks

‘Woods Hole Lab., National Marine Fisheries Serv., Woods Hole, MA 02543

2Virginia Inst. of Marine Science, Gloucester Pt., VA 23062

3North Carolina Div. of Marine Fisheries, Morehead City, NC 28557

4New York Dept. of Environmental Conservation, Stony Brook, NY 11794

5Sandy Hook Lab., National Marine Fisheries Serv., Highlands, NJ 07732

®Nacote Creek Marine Fisheries Lab., New Jersey Div. of Fish, Game, and Wildlife, Absecon, NJ 08201
Delaware Div. of Fish and Wildlite, Dover, DE 19901

U.S. DEPARTMENT OF COMMERCE

Malcolm Baldridge, Secretary

National Oceanic and Atmospheric Administration
John V. Byrne, Administrator

National Marine Fisheries Service

William G. Gordon, Assistant Administrator for Fisheries

Northeast Fisheries Center

Woods Hole, Massachusetts

January 1983


~13-

T
42%
40%
384
364
120 240
KILOMETERS
80° 82°
Figure 1. Location of sample collection sites for summer flounder, n

Paralichthys dentatus, stock discrimination analyses (NY = New
York, NJ = New Jersey, NNC = northern North Carolina, and SNC =
southern North Carolina).


(continued from inside front cover)

8. Phytoplankton Community Structure in Northeastern Coastal Waters of the
United States. I. October 1978. By Harold G. Marshall and Myra S. Cohn.
August 1981. Revised and reprinted October 1981. v + 14 p., 4 figs., 1 app.

9. Phytoplankton Community Structure in Northeastern Coastal Waters of the
United States. II. November 1978, By Harold G. Marshall and Myra S. Cohn.
August 1981. Revised and reprinted October 1981. v + 14 p., 3 figs., 1 app.

10. Annual NEMP Report on the Health of the Northeast Coastal Watere of the
United States, 1980. Northeast Monitoring Program Report No. NEMP IV 81 A-H
0043. August 1981. Revised and reprinted January 1982. xxi + 79 p., 23
figs., 4 tables, 5 app.

ll. Proceedings of the Summer Flounder (Paralichthye dentatus) Age and Growth
Workshop, 20-21 May 1980, Northeast Fisheries Center, Woods Hole,
Massachusette. By Ronal W. Smith, Louise M. Dery, Paul G. Scarlett, and
Ambrose Jearld, Jr. December 1981. iv + 14 p., 10 figs., 6 tables.

12. Status of the Fishery Resources Off the Northeastern United States for
1981. By Resource Assessment Division, Northeast Fisheries Center. January
1982. iii + 114 p., 44 figs., 44 tables.

13. Gulf and Atlantic Survey for Selected Organic Pollutants in Finfish. By
Paul D. Boehm and Pam Hirtzer. April 1982. vii + 111 p., 46 figs., 31
tables, 2 app.

14. Eeosystem Definition and Community Structure of the Maerobenthos of the
NEMP Monitoring Station at Pigeon Hill in the Gulf of Maine. By Alan W.
Hulbert, Kenneth J. Pecci, Jonathan D. Witman, Larry G. Harris, James R.
Sears, and Richard A. Cooper. May 1982. xii + 143 p., 16 figs., 10 tables, 9

app.

15. Seasonal Phytoplankton Assemblages in Northeastern Coastal Waters of the
United States. By Harold G. Marshall and Myra S. Cohn. July 1982. vi + 31
p-, 8 figs., 2 tables.

16. Contaminants in New York Bight and Long Island Sediments and Demersal
Species, and Contaminant Effects on Benthos, Summer 1980. By Robert N. Reid,
John E. O'Reilly, and Vincent S. Zdanowicz, eds. September 1982. x + 96 p.,
36 figs., 21 tables.

17. Summary of the Physical Oceanographic Processes and Features Pertinent to
Pollution Distribution in the Coastal and Offshore Waters of the Northeastern
United States, Virginia to Maine. By Merton C. Ingham (ed.), Reed S. Arm-
strong, J. Lockwood Chamberlin, Steven K. Cook, David G. Mountain, Ronald J.
Schlitz, James P. Thomas, James J. Bisagni, John F. Paul, and Catherine E.
Warsh. December 1982. vi + 166 p., 21 figs., 2 tables.


-10-

Table 1. Sample locations and number of specimens used in
analysis of summer flounder, Paralichthys
dentatus, morphometric and meristic data.

Sample
Area size
New York 89
New Jersey 82
North Carolina (South of Cape Hatteras) 123

North Carolina (North of Cape Hatteras) 39



-2-

Smith (1973) suggested that two distinct spawning populations of summer
flounder may occur in the Middle Atlantic Bight on the basis of egg and larval
distribution patterns and that a third spawning group may exist in the South
Atlantic Bight.

In an attempt to provide further insight into stock structure in the
vicinity of Cape Hatteras, the State-Federal Summer Flounder Scientific and
Statistical Committee initiated an analysis of morphometric and meristic data
for summer flounder collected: 1) off New York-New Jersey (NY/NJ),

2) immediately north of Cape Hatteras (NNC), and 3) immediately south of Cape
Hatteras (SNC) (Figure 1). Data collection and preliminary analyses were
undertaken in a workshop sponsored by the National Marine Fisheries Service
(NMFS) and held at the Northeast Fisheries Center's Sandy Hook Laboratory
during September 22-26, 1980.

MATERIALS AND METHODS

Summer flounder were collected from coastal locations in New York, New
Jersey, and North Carolina (Figure 1) by members of the State-Federal
Scientific and Statistical Committee in late summer-fall (Table 1). Specimens
“were obtained specifically for this analysis and were immediately frozen and
stored prior to the workshop. A total of 18 morphometric and meristic
characters were measured or counted from each specimen (Table 2). Total
length and body depth were measured to the nearest millimeter; remaining
measurements were made to the nearest 0.5 mm using dividers and a metric
ruler.

Measurements and counts were taken by four teams, each comprised of two
individuals. An attempt was made to standardize measuring techniques

carefully prior to data collection. To reduce potential measurement bias



-iii-

TABLE OF CONTENTS

INtPOdUCtiONn.sscccccsccvcevccscccccesccsccescescsesesesseeel

Materials and MethodS...seccccrccccsrccccssccvcvscvseseseened

RESUIES .ccecccecsececscnceee

dene eneerseneeeeerened

DISCUSSION. cecceccecccuccererscenccescsecerecesessssscseseed

ACKNOWL edgeMeNntS ..ccescccccvccccceccrcscescceseesersoesercel

Literature Cited. .cscccccccccccsccccencceccrstseccessesseeel

FOOCNOCC  ceceeescrreccescccenserecenessereersereseserneec eed

Tables:

1.

3.

Figures:

1.

2.

Sample locations and number of specimens
used in analysis of summer flounder,

Paralichthys dentatus, morphometric and

MEPTSCIC datarcrscccccccceercccccvesceesservereell
Description of morphometric and meristic

variables used in linear discriminant

analysis of summer flounder, Paralichthys
dentatus..

soeveeeseell

Variables used in two-group linear

discriminant analysis separating summer

flounder, Paralichthys dentatus, collected

off New York-New Jersey (NY/NJ) and south

of Cape Hatteras (SNC) including resulting
discriminant coefficientS...ccesccceccceeeeceseel2

Location of sample collection sites for

summer flounder, Paralichthys dentatus, stock
discrimination analyses (NY = New York, NJ =

New Jersey, NNC.= northern North Carolina,

and SNC = southern North Carolina)....sseeseeere13

Canonical variable plot of summer flounder,
Paralichthys dentatus, group centroids for
New York-New Jersey TNY/NJ), northern North
Carolina (NNC), and southern North Carolina
(SNC) based on stepwise linear discriminant

ANALYSIS cccvcccccccccccvcsccscccsccvccscccceseee ld




-ll-

Table 2. Description of morphometric and meristic variables used in linear
discriminant analysis of summer flounder, Paralichthys dentatus.

Variable

Description

Standard length

Body depth

Maxillary union

Maxillary

Preoperculum

Head length

Dorsal snout length
Ventral snout length

Posterior margin dorsal eye
Posterior margin ventral eye

Interorbital width
Dorsal eye length
Ventral eye length

Dorsal eye width
Ventral eye width

Preanal length

Upper gill rakers

Lower gill rakers

Distance between base of dorsal to base
of ventral fin at deepest part of body.

Distance from anterior tip of snout to
posterior margin of maxillary union.

Distance from anterior tip of snout to
posterior margin of maxillary.

Distance from anterior tip of snout to
most distant point of preopercular
membrane.

Distance from anterior tip of snout to
most distant point of opercular
membrane.

Distance from anterior tip of snout to
anterior margin of orbit.

Distance from anterior tip of snout to
posterior margin of orbit.

Minimum distance between dorsal and
ventral eye orbits.

Distance between anterior.and posterior
margins of eye.

Distance between dorsal and ventral
margins of eye.

Distance between measuring board end
plate to anterior margin of anus.

Number of epibranchial gill rakers.

Number of ceratobranchial gill rakers.



INTRODUCTION

\

~ The summer flounder, Paralichthys dentatus, is among the most sought
after and valuable commercial and recreational species found in the Northwest.
Atlantic. Total United States commercial landings of summer flounder in 1981
were 10,800 metric tons (mt) with an estimated total ex-vessel value of
approximately 17 million dollars, (U.S. Department of Commerce, 1982).
Estimated 1979 recreational landings were 8,626 mt with an seas tore1 2.13 x
105 summer flounder captured. and released by sport fishepnen’ (U.S. Department
of Commerce, 1980). A Fishery Management Plan has been developed for this
species by the State-Federal Summer-“F lounder Scientific and Statistical
Committee, approved by the Atlantic States Marine Fisheries Commission, and is
currently being evaluated by the Mid-Atlantic Fishery Management Council.

\Sconsiderable attention has been devoted in recent years to determining
the population structure of summer flounder in the Middle and South Atlantic

Bights. Wi}k et al. (1980) concluded that summer flounder north and south of
> A asp, Bit thet Chia bid 4» tom

ee

Cape Hatteras, North Carolina comprise distinct populations on the basis of
stepwise linear discriminant analysis of morphometric and meristic

variables. Summer flounder collected throughout the Middle Atlantic Bight
were statistically similar, as were fish sampled in the South Atlantic

Bight. Population intermixing was most prevelant off North Carolina. Smith
and Daiber (1977) analyzed summer flounder meristic data available from
Delaware and Chesapeake Bays and off Beaufort, North Carolina; although ‘no
conclusive evidence of significant differences between Delaware Bay and
Chesapeake Bay samples was found, anal fin ray and gill raker counts differed
significantly between these locations and North Carolina samples. Ginsburg
(1952) had earlier suggested that meristic characters differed between summer

flounder collected in Chesapeake Bay and off Beaufort, North Carolina.


pAn-P3Z0R 1007 PBa3 168856
M" iit

NOAA Technical Memorandum NMFS-F/NEC- 18

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Stock Discrimination
of Summer Flounder (Paralichthys dentatus)
in the Middle and South Atlantic Bights:
Results of a Workshop

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration ©
National Marine Fisheries Service

Northeast Fisheries Center

Woods Hole, Massachusetts

January 1983


however, the number of specimens available for analysis was small.The

classification matrix of observed and predicted group membership was:

Predicted
Observed NY/NO SNC) NNC.
NY/NJ 113 23 35
SNC 16 92 15
NNC 8 11 20

The relatively high level of misclassification for the northern North
Carolina samples (NNC) may be indicative of intermixture of northern and
southern groups.

The five variables chosen for construction of the two-group discriminant
analysis were: 1) ventral eye width, 2) body depth, 3) posterior margin of
dorsal eye, 4) standard length, and 5) dorsal eye width. These five

_ morphometric variables provided a significant (F = 39.94; d.f. = 5.288;

Pp <0.01) discriminant function (Table 3). No meristic variables were chosen
as discriminators for this analysis. Discriminant scores were. -0.0252 and
-0.0349 for the New York-New Jersey and south of Cape Hatteras groups,
respectively. Individuals with discriminant scores greater than -0.0301 were
assigned to the northern group and those with scores.less than this value were
classified as southern fish. The Mahalanobis (1936) distance measure (D2)
derived from the two-group discriminant analysis was 2.830, implying a
probability of correct classification of approximately 80% by the method of
Rao (1952).

DISCUSSION

Results of this analysis support the findings of Wilk et al. (1980) that

summer flounder north and south of Cape Hatteras are statistically separable



-3-

further, specimens from each geographical group were randomly assigned among
teams, i.e., teams worked simultaneously on specimens from each location.
Initial analyses indicated no significant sex-related differences in
morphometrics or meristics (ANOVA; p >0.05), accordingly, data were combined
by sex. To standardize for differences in length composition among samples,
variables were expressed as the ratio of each morphometric character to total
length. Ratios for each variable within each area were regressed on total
length and the resulting regression lines tested for zero slope (t-test;
p <0.05). Prior to analysis, each proportion was treated with an arcsine
square-root transform (Sokal and Rohlf, 1969). Regressions for four variables
exhibited slopes which differed significantly from zero for two or more groups
and these variables were not used in subsequent analyses. For all remaining
variables, it was assumed that growth was allometric within the size ranges
available for analysis. Residuals from remaining regression equations were
examined for possible bias with no evidence of nonlinear trends noted.
Stepwise linear discriminant: analysis was employed to differentiate among
fish collected in the three areas using Biomedical Computer Program BMDO7M
(Dixon, 1971). The five variables which contributed most significantly to the
three-group discriminant analysis were subsequently used in a two-group linear
discriminant analysis (BMDO4M) to compare summer flounder collected off New

York-New Jersey with those obtained south of Cape Hatteras.
RESULTS

Samples collected off New York-New Jersey were clearly differentiated
from those obtained south of Cape Hatteras using the three-group stepwise
linear discriminant analysis (Figure 2). Samples collected immediately north

of Cape Hatteras could not be reliably classified as a discrete group;




SECOND CANONICAL VARIABLE

-14-

32 ot Oo

t T T t 1 T t
3+ +3
2+ +2
1+ +4

NY/NJ} SNC
Of QO to
“ad 1,
NNC @)

2+ | fo
-3+ +-3

t t + : t t t

-3 -2 -1 6) 1 2 3

FIRST CANONICAL VARIABLE
Figure 2, Canonical variable plot of summer flounder, Paralichthys dentatus,

group centroids for New York-New Jersey (NY/NJ), northern North
Carolina (NNC), and southern North Carolina (SNC) based on stepwise

linear discriminant analysis.





-7-

ACKNOWLEDGEMENTS ©

The authors wish to thank Mr. Jon Gibson and Dr. Michael Sissenwine,
NMFS, Woods Hole Laboratory, for their constructive comments and criticisms,
and editorial advice on the manuscript. In addition, we would like to give
special thanks to Ms. Michele Cox, NMFS, Sandy Hook Laboratory, for her advice
leading to, and the actual preparation of, the figures used in this

publication.
LITERATURE CITED

Dixon, W. J. 1971. Biomedical Computer Programs. Univ. Calif. Press, Los
Angeles, 773 p.

Ginsburg, I. 1952. Flounders of the genus Paralichthys and related genera in
American waters. U. S. Fish and Wild. Serv., Fish. Bull., 52:267-351.

Lux, F. E., and F. E. Nichy. 1980. Movements of tagged summer flounder,
Paralichthys dentatus, off Southern New England. Nat. Mar. Fish. Serv.,
Northeast Fish. Ctr., Woods Hole Lab., Lab. Ref. Doc. No. 80-34, 20 p.

Mahalanobis, P. C. 1936. On the generalized distances in statistics. Proc.
Nat. Inst. Sci. India, 2(1):49-55.

Murawski, W. S. 1970. Results of tagging experiments of summer flounder,
Paralichthys dentatus, conducted in New Jersey waters from 1960-1967.
N. J. Div. of Fish, Game and Shellfish., Misc. Rep. No. 5M, 72 p.

Poole, J. C. 1962. The fluke population of Great South Bay in relation to
the sport fishery. N. Y. Fish and Game J., 9(2):93-117.

Rao, R. C. 1952. Advanced Statistical Methods in Biometric Research. John
Wiley and Sons, Inc., New York, 390 p.

Smith, W. G 1973. The distribution of summer flounder, Paralichthys
dentatus, eggs and larvae on the continental shelf between Cape Cod and

Cape Lookout 1965-1966. Fish. Bull., U. S., 71(2):527-548.


-9-

FOOTNOTE ,

\ohn W. Gilliken, Jr., North Carolina Division of Marine Fisheries,
Morehead City, North Carolina 28557.


BIBLIOGRAPHIC INFORMATION

PB83-168856

Stock Discrimination of Summer Flounder (Paralichthys
dentatus) in the Middle and South Atlantic Bights: Results
of a Workshop,

Jan 83

Michael J. Fogartry, Glenn DeLaney, John W. Gillikin, Jr.,
John C. Poole, and Daniel E. Ralph.

PERFORMER: National Marine Fisheries Service, Woods Hole,
MA. Northeast Fisheries Center.
NOAA-TM-NMFS-F/NEC-18

The summer flounder, Paralichthys dentatus, is among the
most sought after and valuable commercial and recreational
species found in the Northwest Atlantic. Total United States
commercial landings of summer flounder in 1981 were 10,800
metric tons (mt) with an estimated total ex-vessel value of
approximately 17 million dollars. (U.S. Department of
Commerce, 1982). Considerable attention has been devoted in
recent years to determining the population structure of
summer flounder in the Middle and South Atlantic Bights. The
report describes these.

KEYWORDS: *Flatfishes, *Midatlantic Bight, *South Atlantic
Bight, *Meetings, *Paralichthys dentatus.

Available from the National Technical Information Service,
Springfield, Va. 22161

PRICE CODE: PC A02/MF A01


NOAA TECHNICAL MEMORANDUM NMFS-F/NEC

The Northeast Fisheries Center (NEFC) conducts targeted research to
provide needed information for fisheries resource and habitat managers in the
Northwest Atlantic. The NEFC operates facilities in Gloucester and Woods
Hole, Massachusetts; Narragansett, Rhode Island; Milford, Connecticut; Sandy
Hook, New Jersey; and Oxford, Maryland. It also administers the NMFS's
National Systematics Laboratory in Washington, D.C., and Atlantic
Environmental Group in Narragansett, Rhode Island. This targeted research
focuses on: (1) harvesting, aquaculture, and utilization of fisheries
resources; and (2) the health of the marine environment as it affects the
production and edibility of fisheries resources. Users of this information
include federal and state agencies, private industry, and the general public.

The real-time need for this information by decision makers often
precludes publication in formal journals. The NOAA Technical Memorandum NMPS-
F/NEC series identifies informal documents prepared by NEFC authors or similar
material prepared by others for NEFC purposes, where formal review and
editorial processing are not appropriate or feasible. However, documents
within this series reflect sound professional work and can be referenced in
formal journals. Any use of trade names within this series does not imply
endorsement.

Copies of this and other NOAA Technical Memorandums are available from
the National Technical Information Service, 5285 Port Royal Rd., Springfield,
VA 22161. Recent issues of NOAA Technical Memorandum NMFS-F/NEC are noted
below:

3. Definition of Management Unite. By Emory D. Anderson and Guy D.
Marchesseault. October 1980. v+4p., 4 figs., 1 table.

4. Fishery Management Techniques, A Review. By Michael P. Sissenwine and
James E. Kirkley. October 1980. v + 10 p.

5. The Statue of the Marine Fishery Resources of the Northeastern United
States. By Margaret M. McBride and Bradford E. Brown. December 1980. vii +
13 p., 4 figs., 3 tables.

6. Economie and Biological Data Needs for Fisheries Management, With
Particular Reference to the New England and Mid-Atlantic Areas. By Guy D.
Marchesseault, Joseph J. Mueller, and Ivar E. Strand, Jr. December 1980. v +
10 p., 1 fig., 3 tables.

7. Methodology for Identification and Analysis of Fishery Management
Options. By Brian J. Rothschild, Richard C. Hennemuth, Jacob J. Dykstra, Leo
C. Murphy, Jr., John C. Bryson, and James D. Ackert. December 1980. v + 10
p., 5 figs., 1 app.

(continued on inside back cover)



“5.

on the basis of morphometric characters. In the vicinity of Cape Hatteras,
apparent intermixing of northern and southern contingents occurs. Summer
flounder collected immediately north of Cape Hatteras could not be reliably
identified as a discrete group; however, the number of specimens available for
analysis was small, possibly obscuring differences among groups. Wilk et al.
(1980) reported, however, that summer flounder obtained north of Cape Hatteras
were aligned more closely with Middle Atlantic Bight samples than those
collected in the South Atlantic Bight. Intermixture of northern and southern
groups in the North Carolina areas was evident in this analysis. A recent
tagging study conducted off North Carolina (J. Gillikent, pers. comm.)
indicated a northerly trend in movements during spring and summer, i.e., fish
released off North Carolina during winter were primiarly recaptured in
Chesapeake Bay in summer.

Phenotypic plasticity due to environmental effects cannot be discounted
and no attempt to ascribe genotypic differences for these morphometric
characters is made. Despite an attempt to standardize measurements to account
for possible differences in size composition among the samples, it is possible
that size-related effects were not completely eliminated, contributing to the
observed differences among areas.

The probability of correct classification based on the discriminant
function derived in the present study was lower than that obtained by Wilk
et al. (1980), possibly due to smaller sample sizes. Despite attempts to
standardize measuring techniques carefully, additional variability may have
resulted from the use of several measurers.

Results of this study support the findings of Ginsburg (1952), Smith and
Daiber (1977), and Wilk et al. (1980) in identifying meristic and morphometric

differences in summer flounder in the Middle and South Atlantic Bights.


-8-

Smith, R. W., and F. C. Daiber. 1977. Biology of the summer flounder,
Paralichthys dentatus, in Delaware Bay. Fish. Bull., U. S., 75(4):823-
830.

Sokal, R. R., and F. J. Rohlf. 1969. Biometry. 2nd edition. W. H. Freeman
and Co., San Francisco, CA, 859 p.

U. S. Department of Commerce. 1980. Marine recreational fishery statistics
survey, Atlantic and Gulf coasts, 1979. U. S. Dept. Commerce, NOAA, NMFS,
Current Fish. Statist. No. 8063, 139 p.

U. S. Department of Commerce. 1982. Fishery statistics of the United
States. U. S. Dept. Commerce, NOAA, NMFS, Current Fish. Statist. No.
8200, 131 p.

Wilk, S. Je, W. G. Smith, D. E. Ralph, and J. Sibunka. 1980. The population
structure of summer flounder between New York and Florida based on linear

discriminant analysis. Trans. An. Fish. Soc., 109(3):265-271.