752
NOAA Technical Report NMFS SSRF-752 Movements of Tagged Summer Flounder, Paralichthys dentatus, off Southern New England
F. E. Lux and F. E. N ichy
December 1981
u.s. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Marine Fisheries Service NOAA TECHNICAL PO
National Marine Fisheries Service, Special Scientific Report-Jo1 ..iUlftlM
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Iii .. 35 p .• 4 figs .• I table 740 food of firtern nonhwnt l!antIC pdirorm 729 ReferenCe<> for the Idenllficallon of manne on' Movements of Tagged Summer Flounder, Paralichthys dentatus, off Southern New England F. E. Lux and F. E. N ichy December 1981 u.s. DEPARTMENT OF COMMERCE Malcolm Baldrige, Secretary National Oceanic and Atmospheric Administration John V. Byrne, Administrator National Marine Fisheries Service The National Marine Fisheries Service (NMFS) does not approve, rec ommend or endorse any proprietary product or proprietary material mentioned in this publication. No reference shall be made to NMFS, or to this publication furnished by NMFS, in any advertising or sales pro motion which would indicate or imply that NslFS approves, recommends or endorses any proprietary product or proprietary material mentioned herein, or which has as its purpose an intent to cause directly or indirectly the advertised product to be used or purchased because of this N~FS publication. CONTENTS Introduction ...... Tagging procedure ...... Results ...... Offshore tagging, April 1961 ...... 3 Inshore tagging, September 1962 ...... Discussion ...... Literature cited ...... 15 Figures 1. Map of the Middle Atlantic Bight showing locations where summer flo under were tagged and released in J961 and 1962...... 2 2. Length-frequency distributions of summer fl ounder tagged in April 1961 on offshore grounds and of tho. e subsequently recaptured...... 3 3. Tagged summer flounder release positions for April 1961 releases and recapture locations in April-J une 1961 4 4. Tagged summer flounder release positions for A pril 1961 releases and 1961 recapture positions In July- September and October-December ...... 5 5. Tagged summer flounder release positions for April 1961 releases and 1962 recapture locations in Januar)- March and April-June ...... 6 6. Length-frequency distributions, at tagging, of m ale and female summer flounder recaptures from fish tagged in 1961 on offshore grounds and in 1962 on inshore grounds...... 7 7. Length-frequency distributions of summer flounder tagged in September 1962 in Block Island Sound and of those subsequently recaptured ...... 8. Length-frequency distributions of summer fl ounder tagged in September 1962 in Nantucket Sound and of those subsequently recaptured ...... - ...... H 9. Tagged summer flounder release positions for September 1962 releases and 1962 recapture locations in September and October-December ...... 9 10. Tagged summer flounder release positions for Septem ber 1962 releases and 1963 recapture locations in January-March and April-June ...... 10 11. Tagged summer flounder release positions for September 1962 releases and 1963 recapture location in Jul}- September and October-December...... II 12. Tagged summer flounder release positions for Septem ber 1962 releases and 1964 recapture locations in January-March and April-June ...... 12 13. Tagged summer flounder release positi,ms for September 1962 releases and 1964 recapture locations In Jul)- September and Octobe~-Decemb e r ...... U Tables I. Recoveries of tagged summer flounder from 1961 offshore releases by ~eason and fisherman I} pe, April 1961-0ctober 1963 ...... 7 2. Recoveries of tagged summer flounder from 1962 inshore releases by sea on and fisherman type, eplember 1962-JanuaryI968...... 14 3. Numbers of tag recaptures north and south of lat. 39°N in January-March 1963 and 1964 from 1962 in~hore releases, and mean lengths and length ranges, in centimeters, at time of tagging ...... IS III Movements of Tagged Summer Flounder, Paralichthys dentatus, off Southern New England F. E. LUX and F. E. NICHY' ABSTRACT A total of 2,839 summer flounder were tagged on outer continental shelf and coastal grounds off southern New England in 1961-62. Tag recaptures showed the migration to offshore grounds in fall and winter and to inshore areas in spring and summer. Recaptures from coastal grounds were recorded from northern New Jerse) to south of Cape Cod; those from outer shelf grounds were from Baltimore Canyon on the southwest to Veatch Canyon on the north east. The overall tag return rate was 21.2"70 ; however, the returns from inshore tagging (44.5"70) were much higher than those from offshore releases (8.4 "70) , suggesting that tagging mortality was higher offshore. INTRODUCTION mm mesh cod ends, also showed a scarcity of summer flounder < 28 cm long. 2 Adults of summer flounder, Paralichthys dentatus, are found Marking studies off New York and New Jersey have shown in Atlantic coastal waters from Maine to Florida (Bigelow and the seasonal pattern of movement of this species: In the fall Schroeder 1953; Wilk et al. 1980). They are most abundant in from coastal areas to the outer continental shelf winter grounds, the Middle Atlantic Bight, the coastal concavity between Cape and in the spring returning to the coast (Westman and Neville 3 Cod and Cape Hatteras, where they are fished intensively (Fig. 1946; Poole 1962; Murawski 1970 ). These studies also indicated 1). From late spring to fall summer flounder are sought by that with the passage of time the tagged fish tended to be caught recreational and commercial fishermen in coastal areas; from farther to the north within the bight. December to April they are fished by otter trawlers along the To learn more about the seasonal and long-term movements outer continental shelf edge. Vessels from New Jersey to of summer flounder off southern New England, we tagged 2,839 Virginia fish this species in the southern part of the bight; those of these fish on both coastal and offshore grounds in 1961-62. from New York and New England fish the arpas from Long The results of this study are repo_ted here. Island to south of Cape Cod. The reported commercial catch of summer flounder in 1979 TAGGING PROCEDURE was 13,932 t, of which 3,220 t were taken within 3 mi (5.5 km) from shore and 10,712 t were from waters beyond 3 mi but The summer flounder for tagging were caught with otter within the 200-rni (370 km) conservation zone (Pileggi and trawls. For the offshore tagging we used the Bureau of Com Thompson 1980) . The recreational catch for 1979, which we mercial Fisheries' RV Delaware. For the inshore tagging we used commerical otter trawlers. Tow length varied from 30 to 60 estimated from angler survey data (National Marine Fisheries Service 1980), was about 10,000 t. min. On the Delaware the fish were held in tanks of running seawater until tagged, whereupon they were immediately re Young-of-the-year summer flounder occur sporadically in leased. On the commercial vessels the fish were tagged from the bays from southern New England to New Jersey; however, the net as they were brought aboard and then immediately released. principal nursery grounds are in estuaries and bays of Virginia Total length in millimeters, date, and tagging location were and North Carolina (poole 1966). The fish apparently disperse recorded for each tagged fish. All of the summer flounder northward as they grow older and make up the stocks that are caught were tagged, except for the small number, of various exploited in the northern part of the bight. Fish < 25 cm in sizes, whose physical appearance indicated that they were mori length are uncommon in New York waters (Westman and bund. Therefore the tagged population was considered represen Neville 1946). This also appears true of southern New tative of the catch. England; we measured samples from commercial otter trawl The seasons for tagging were chosen to minimize loss of tag catches of this species there in 1960-62 and found no fish < 28 ged fish to fishing before they had moved from release areas. cm long in 18 trips from offshore areas and 5 from inshore Thus, the 1961 offshore tagging was done in early April, which areas. This was not due to discarding the smaller fish, since the entire catch of New England summer flounder is marketed. The cod end mesh sizes in the trawls for the 23 trips were mostly 114 'Sissenwine, M. P., R. R. Lewis, and R. K. Mayo. 1979 The spatial and mm or less and would have retained flounders smaller than 28 seasonal distribution of summer flounder (Paraiichlhys denlalus) based on research cm (Lux 1968). National Marine Fisheries Service otter trawl vessel bottom trawl surveys. Northeast Fisheries Center. National \Iar',e survey catches in 1964-79 off southern New England, using 15 Fisheries Service, Woods Hole, Mass. Lab. Ref. No. 79-55. 9 P ' Murawski, W. 1970. Results of tagging experiments of summer flounder, Paralichlhys denlalus, conducted in New Jersey waters from 1960-67. '-; J Dep 'Northeast Fisheries Center Woods Hole Laboratory, National Marine Fisheries Environ. Prot., Misc. Rep. 5M, 45 p. (N.J. Division of Fish. Game and Service, NOAA. Woods Hole, MA 02543. Shellfisheries, 80'\ 1809. Trenton, .J.08625.) -~~:---'J/~J f iOS/'){) · ..... , . ( nov/cit"'/) I J "" .,.-' ( I \ ,/ 1: / g\l' ) Cape 2:~ 9., RELEASE LOCATIO ~S r(1) 5') FISH,APRI '961 o 6 FISH, APRIL 1961 ~ 14 FIS • PRI~ 1%1 @ 1,75BF ,APR _ 1961 + ® 4 FI$H.C;~PTE. .1ElE 1962 @ 600fJ5H.SEPTEV8E~ 962 ------+------~- ---- 71 0 Figure I.-Map of the Middle Atlantic Bight showing locations where summer flounder were tagged and released in 1961 and 1962. 2 ; near the end of the winter fishery, and the 1962 inshore tag In April-June 1961 there were 67 tag recaptures, all \\Jlh ing was done in September, near the end of the summer fis hery. recapture positions noted. Of these, 37 were caught in April on Fish just tagged were sometimes caught in subsequent tagging offshore areas in the vicinity of tagging (Fig 3). In addlll n, )ws. If these fish appeared lively, they were re-released and three late April recoveries were caught on inshore area~ of long ~ cords were made of the fact. Island. The other 27 recovenes were caught in l\.1a} and June on The mesh in the cod ends of trawls used to catch the fish for inshore grounds, primarily from the ocean side of Long I land. 199ing had a stretched measure of about 90 mm. This mesh re One, however, was from Long Island Sound, three \\ere tram Lins flounders down to 20 cm or so in length (Clark et al. 1958; the Rhode Island shore, and two were from Vineyard ound ux 1968). We caught no summer flounder smaller than 31 cm, Oust south of Cape Cod). The returns during this quarter nd we, therefore, assume that the entire size range of fi sh was established the time of movement from off hore to In~horc ampled in relation to its abundance and that none e caped grounds as April and May, at least for the area dealt with in thi lrough the meshes. report, i.e., north of lat. 39°N. Each tag consisted of two plastic Peterson disks, 13 mm There were 47 summer recoveries (July-September 1961),46 iameter, joined by a stainless steel pin passing through the of which had return locations noted. They were caught mostl) in orsum of the fish. One disk was printed with return instruc bays and sounds from Long Island to southern New England ons; the other carried a serial number. (Fig. 4). Many of these recoveries were from more easter I} in A reward of $1.00 was paid for a returned tag alone, and shore areas than the spring ones, although there \~ere also 12. 00 for a tag with the fish. Bureau of Commercial Fisheries several from off western Long Island and Long Island ound. ort samplers, who were stationed in ports of landing, received Six returns were from as far to the east as Vineyard and an 10st of the tags and fish returned by commercial fishermen. Sex tucket Sounds. There were no summer recoveries from south of nd length of returned fish were recorded. Positions for recap Sandy Hook, N.J., or from east of the elbow of Cape Cod. lres by the commercial fleet usually were in the form of loran There were just three recoveries in the fall of 1961 (October earings and depths, which generally were accurate to within 10 December), for one of which no return area was given. The m or less. other two were from south of Martha's Vineyard and an Recreational fishermen usually mailed in their recovered tags . tucket, in an area intermediate between inshore and off hare 'hey frequently gave the recovery position in terms of land grounds, suggesting that these fish were in the process of mo'.ing ~ arks, such as an inlet, bay, or point. These positions probably offshore for the winter (Fig. 4). One of these \~as caught in Oc {ere at least as accurate as those for commercial returns. tober, the other in December. For tags discovered in fish markets or processing plants there There were 28 recoveries during January-March 1962, all of (as no information on recovery position; however, usually it which were from offshore, and 15 of them came from the vi {as possible to identify them as commercially caught. For a few cinity of release in the previous spring (Fig. 5). In addition, 10 f the tags that were mailed in, no data could be obtained. Both others were caught well to the east of this, near Veatch Canyon, ources of unplaced tags made up 3.8070 of the total returns. suggesting that the fish had moved .:astward. rhe other three Vhile they were of no value for charting fish movements, they fish were recaught south of the release point, Indicating that {ere useful in measuring total return rates and are included in some southerly movement had taken place Je results presented below. Of the five recaptures reported for April-J une 1962, two were caught on offshore grounds in April and May and the other RESULTS three were caught on Long Island inshore areas in May and June (Fig. 5). While there were few returns in this calendar quarter, )ffshore Tagging, April 1961 the pattern of return locations was similar to that of April-June in 1961 (Fig. 3). From 1 to 6 April, summer flounder were caught and tagged n depths of 80-145 m (Fig. 1). Most of the 1,833 fi sh tagged 15,------vere from between Hudson and Block Canyons in about 90 m lepth, approximate position lat. 39 °55 'N, long. 72 "OO'W (Ioca ion 4, Fig. 1). Recoveries were obtained until August 1963, at hich time a total of 155 had been reported, 8.4% of those released. 1:;10 z To compare the length distribution of recaptured fi sh with w hat of the tagged ones we used the fish lengths recorded at the § a: u. me of tagging rather than those obtained at recovery. The size .... Z Iistributions, at tagging, of the fish released in 1961 and of hose subsequently recaught (Fig. 2) show that most of the fish ~ 5 agged were about 31-50 cm in length, with some over 60 cm; the [lean length was 38.8 cm. The lengths, at tagging, of the re 'aptured fish were similar to those of the tagged ones (Fig. 2), uggesting that there was no significant differential in tagging ortality with fish size and that the size of recaptured fish was 0~~-~~~---~~-~4~5~--~~~~~~~-~~- · J 'epresentative of the tagged population. The mean length of 'OrAL ..£',j(;TH (01 'ecaptured fish was also 38.8 cm. All except one of the recoveries from 1961 releases were from .ij(ure 2.-1 enj!lh-''''Quenn d"lrihulinn, III ummtr Iloundtr I. rd In \pn 'i h released at location 4 in Figure I; the following di cu ion 1961 on orr,hore ~rnund, and "I Ih".... ,uh"'quenlh rt... plurffi I II knl:1h art' lpplies to movement from this release point. Ihlhe oblained al Iht lim. 01 lagging" 3 " ', . . ' . . . ,', " , 0 " o· 40° ~ ..:::::... • 0 (1;> 0 ~<:} (10 •• ~ o -:5 -.£. ~ "".l:. 0 -.£. c:. ~ 0 , : 0- ~ ( (1 V' J o 0 ~ ~ Ca~ : -.£. I 0 39° ~ ( , .... .May \ -----+------r------1 ------+------.------+------t : 1.(~ : () : () : ..... Figure 3.- Tagged summer flounder release positions for April 1961 releases (open squares) and recapture locations in April-June 1961 (circles), 4 . '. ' . .. ': ' :: . " , ...... ". / "" f .: : .... : ..... o . :.' " D c······ , _/ / { I Ca~I (,,, .May ) : :.' Figure 4. - Tagged summer flounder release positions for April 1961 releases (open squares) and 1961 recapture positions in July-September (circles) and October December (triangles). 5 ~------I I f I / I -- .... ,.. , .: "- \ I ) / l I / ------~- ---~-+~- ____L ______"--- ___ L ______-k ______~ 73° 710 Figure 5.- Tagged summer flounder release positions for April 1961 releases (open sQuares) and 1962 recapture locations in January-March (circles) and April-June (triangles). 6 Table I.-Recoveries of tagged summer flounder from 1961 offshore releases by season and fisherman type, April 1961-October 1963. 1961 OFFSHORE GROUNDS 5 Number of recoveries by fisherman type Period of Commer- Recrea- recovery cial tional Unknown Total 1961 1962 B..OCK ISU\JIO SAlt;{) April-June 60 7 67 I July-September 13 32 2 47 1£ 5 u. October-December 2 3 a 1962 7 15r------1962 BLOCK ISLAND SOUND 15 TAGGED( N 406) RET JRNLU (N Zr I) l >- ~IO w >10 ::J u 8a:: ~ " , > z a:: w u " cr >z It w 5 W 0. J J.. 50 55 TOTAL LENGTH (eM) Figure 7.-Length-frequenQ distribution, of \ummer flounder tal/.I:cd in "cplcmh,r 1%2 on UI,, 8 PLlJS n St PTEMBt R RlCI\PTURCS I '--- / 41 ° • ( ~ • j -~, :~--+-- .---.:...... - -:-. 40° \P .c:... "6 ro (l0 I 0 • I o -,-- (l0 ::> 0 -;5 .' I --L.. • 0 3:. --:l- ::> 0 c::. ::> 0- (lV" o 0 ::> ::> ~ 0 ::> 39° \ \ I :2:.. I ~ / "3 H _____ r- t 38° I ~ I ~ C> "? 0 0 ~- ::> ::> / --L.. ~ 0 ( (-, 0 ::> G --ro ::> -<:. <:) ::> 37° Cope _Ha tteras Figure 9.-Tagged summer nounder release positio ns for September 1962 releases (open squares) and 1962 recapture locations in September (ci rcles) and October December (triangles). 9 ,- ~ ) 42° Cope ( Cod I ~-' J :. ... ( I .... , J -' / 41 ° f .... ';" ::: ':. • • • .. ' '. ~.. :'" ...... ~ . -. • , , • -to • ~•. "%-. "3 38° Q) s (1~ o 0 • ~ 3:. "".:) ~ 0 0 (1 -. "".:) 0 ro "".:) ~ 0 "".:) ,- Figure 10.-Tagged summer flounder re lease posi ti ons for September 1962 releases (o pen squares) and 1963 recapture locations in Janual")-March (circles) and April-June (triangles). 10 .------·--~~~~~~~wr------~------ PLUS 41 JULY-SEPTEMBER RECAPTURES "- " '- ,- ( I N RELEASE AREA " ) , .cope 420 Cod" "- -, "- ) '. ," I I I ) • ,.- (l / 41 • ( • .... ' , t -+--~ "-~,-- ,., . I i • · .. · 1 , / •. . ' " -:LC 0- (1 V' o 0 -;) -;) .....::. o -;) r------ ")0 7 L Figure 11.- Tagged summer nounder release positions for September 1962 releases (open square) and 1963 recapture locations in Jul}-~ptember (circles) and Oclober December (triangles). 11 ' " '- /' " :~~---='-rl!~ - -~- " 420 \Cope ( \ Cod, I " . ) ' ...... "'. \ ) " "' ") ( I / . I / I • --~ .. . -~· .....r ·· ,• . " " 0c.s ~ • . ~ -:r..c.f 0":) 0- 01..f1 o 0 • ":) ":) ~o .'• ":) I ~ . .; "3 + cP 0.s!?. ~ 0 0 ":) ":) ~ ~ 0 0 ":) (1 - o ro ":) ~ 0 ":) 7 0 7'"'0 7 '0 (Opdl "'I" ",,) nd) ;.I r plur~ I,,,, 110 '" ) .''''~n. 1 ,d'ilord I un o! \~' rl) lIOn (Ori ) .. " \ ' ...... "- '- r '- l Cope) ------"- \ \ ( ",,,,-J<"','-"- \ Cod" I I '-~ \ ":" .'. ) ( , ,','.. '- " ...... ' ' .... . " '\ ) ( , ) ( .... ". ' ..;. : .... - ---.__ .,--_._--_.- I h:n /' I ~ I' -"3 : 0 ,(I ~ I ~ o -::I f;;n=__ =~ +-----~- -- Figure B .-Tagged summer flounder release positions fo r September 1962 releases (open squares) and 1964 recapture locations in July-September (circles) and October December (triangles). 13 It seems clear from the above that a significant number of the Table 2.-Recoveries of tagged summer nounder from 1962 inshore summer flounder from inshore releases died from the catching releases by season and fisherman type, September 1962-January 1968. and tagging operations. This mortality needs to be considered in Number of recoveries by fisherman type estimating population parameters from the tag return data. Period of Commer- Recrea- The summer flounder tagged in April 1961 on offshore recovery cia! tiona! Unknown Tota! grounds (Fig. I) moved during the spring and summer north 1%2 September 34 36 west, north, and northeast to coastal areas; there was no move October-December 25 25 ment to the south of the Sandy Hook, N.J., area (Figs. 3-5). 1%3 During the fall the movement was back toward the offshore January-March 110 110 winter grounds near the outer shelf edge; in the winter all of the 59 April-June 57 2 recaptures were from the offshore grounds with many of them July-September 79 8 88 October-December 9 2 II coming from the vicinity of tagging. Some of the offshore 1%4 returns, however, were from areas up to about 220 km to the January-March 36 36 east of the release point, indicating that there also was some 29 April-June 26 2 eastward movement of summer flounder on offshore grounds July-September 18 19 October-December 2 2 (Fig. 5). None of the returns were from areas east of Veatch , 1965-68 Canyon and, insofar as is known, this is the eastern limit for January-March II II movement of this species in any numbers, although they occa April·June 7 2 9 sionally are caught on Georges Bank (Bigelow and Schroeder July-September 9 10 October-December I 1953). All months 424 16 6 446 Few of the tag recoveries were from offshore areas southwest Percentage 95 .1 3.6 1.3 100.0 of the point of tagging, suggesting that there was little move 'There were 33 tota! recaptures for this period; however, month of ment in that direction (Fig. 5). This apparently was not a result recapture was available for only 32 of these. of lack of fishing effort, since New Jersey vessels regularly fish offshore grounds south of Hudson Canyon in the winter (Widerstrom 1959); if any numbers of tagged summer flounder 1,006 fish tagged on inshore grounds of Block Island and Nan had moved there, it is likely that more would have been caught. tucket Sounds in September 1962 there were 448 recaptures, The general pattern of recoveries from these offshore releases 44.5010 of the total released, obtained over a period of 65 mo indicated that the summer flounder that move as far north as the following tagging. The difference in number recaptured in the winter grounds north of Hudson Canyon become rather perma two groups and the timespan over which they were recaught is nent residents of the northern part of the Middle Atlantic Bight. large, considering that both were exposed to approximately The summer flounder tagged in September 1962 on inshore similar fishing efforts. We attribute this difference primarily to a areas of Block Island and Nantucket Sounds (Fig. 1) moved in greater tagging mortality in the offshore releases, which were the fall and early winter to offshore winter grounds from the from depths of about 90 m and were in less vigorous condition vicinity of Veatch Canyon on the east to as far south as than those tagged inshore, which were from 27 m or less. While Baltimore Canyon (Figs. 9-13). Some of the recaptures from the flounders have no gas bladders to cause decompression in these releases clearly had moved farther south on the offshore jury, they may have been hurt by the rapid pressure drop as they grounds than did those from the 1961 offshore releases. There were brought from deep water to the surface. Tow length may appears to be no clear explanation for this difference, although also have been a factor. The fish tagged offshore were caught in variations in the winter bottom temperature on offshore tows of 45-60 min duration and therefore may have suffered grounds may have altered summer flounder distribution, as was greater injury in the trawl than those on inshore grounds, which suggested by Nesbit and Neville (1935). were mostly caught in tows of 30 min. In addition, tows on the The large cluster of winter returns from the vicinity of Block offshore grounds frequently contained some spiny dogfish, Canyon (Fig. 10) may be regarded, at least in part, as a function Squa/us acanthias, whose rough skin and spines abrade other of fishing effort in this intensively fished area. However, the fishes in the trawl. area also is a productive winter fishing ground for squid (Lux et There was evidence of some tagging mortality among inshore al. 1974), an important summer flounder food. It is possible, releases, also, based on the tag return rate of newly tagged sum therefore, that summer flounder aggregate there to some extent mer flounder that were recaught during later tagging tows and for feeding . re-released. In the Block Island Sound tagging, 23 of the tagged Tag recoveries during the spring and summer of 1963 and 1964 fish recaught during tagging tows were re-released in apparently from the inshore releases (Figs. 10-13) show that the fish in these good condition. Of these only four subsequently were recap seasons moved back inshore to areas from Long Island to south tured, for a total tag return rate of 17.4%. This is much lower of Cape Cod. Many were recaught at points of release. The than the 50% return rate for the Block Island Sound releases as general tendency was for these returns to be made from areas far a whole. In addition to this, two of the Block Island Sound ther to the east as the summer progressed. There were very few releases, which never previously had been recaught, were picked spring and summer returns from inshore areas south of Long up dead and decomposed a few days after tagging in the trawl of Island, further indicating that fish that had moved to New the commercial vessel that had been used during tagging. England waters did not move far to the south in subsequent years. In the course of the Nantucket Sound tagging, 90 of the tag The results from the 1961 and 1962 tagging studies showed ged fish were recaught in later tagging tows and re-released. Of movement patterns similar to those found for fish tagged in in these, 10 subsequently were recaptured, a total return rate of shore waters of New York and New Jersey (Westman and 11.1 %. Again, this was much lower than the 40.8% return rate Neville 1946; Poole 1962; Murawski footnote 3). The New York for Nantucket Sound releases as a whole. and New Jersey summer flounder, however, moved farther 14 e II difficult to settle this question . • RIben of '-I ...... _ ...",.. .nd ...... h .. r Ia. YI . _.9(,4 'rom. 2 ...... ~....-.-.. . nil NESBIT, R. A., and W. C. NEVILLE. SMITH, W. G. 1935 . Conditions affecting the southern winter trawl fi shery. [U .S.] Bur. 1973. The distribution of summer flounder, Paralich/hys denta/us, eggs Fish., Fish, Circ. 18, 12 p. and larvae on the continental shelf between Cape Cod and Cape Look PILEGGI, J ., and B. G. THOMPSON. out, 1965-66. Fish. BuU., U.S. 71:527-535. 1980. Fisheries of the United States, 1979. Natl. Mar. Fish. Serv., Curro WESTMAN, J. R., and W. C. NEVILLE. Fish . Stat. 8000, 131 p. 1946. Some studies on the life history and economics of the fluke (Para lichthys den/atus) of Long Island waters. Town of Islip, N.Y., Misc. POOLE, J . C. Rep., 15 p. 1962. The fluke population of Great South Bay in relation to the sport WIDERSTROM, F. L., Jr. fishery. N.Y. Fish Game 1. 9:93-11 7 1959. An economic and financial study of the fluke otter-trawl fishery of 1966. A review of research concerning summer flounder and needs for New Jersey. Commer. Fish. Rev. 21(12):17-26. further study., N.Y. Fish Game J . 13 :226-231. WILK, S. 1., W. G. SMITH, D. E. RALPH, and 1. SlBUNKA. SMITH, R. W., and F. C. DAlBER. 1980. Population structure of summer flounder between New York and 1977. Biology of the summer flounder, Paralichthys den/a/us, in Delaware Florida based on linear discriminant analysis. Trans. Am. Fish. Soc. Bay. Fish. Bull., U.S. 75 :823-830. 109:265-271. 16