Sta- Dominant Sta· Dominant Sta- Dominant tlon Buckets species tlon Buckets Species tlon Buckets Species
Martinique Tnnldad Fort-de-France 6 335 AN Chaguaramas Bay 11 1,055 .0 SA , TH Port Antonio 40 SI Port Royal Grande Anses d 'Arlet 4 350 SA , SI , Chupara Bay 4 2470 SA 1 100 AN RS Port 01 Spain Ha rbor 3 500 PL Port Royal Cays 3 1020 DH , SI Port Royal Mangrove St .-Pierre 2 130 RS La s Cuevas Bay 60 PL 45 0 AN St Lucia Lampara Net Dominican Republic Anse ChOiseul 30.0 PL, TH Jamaica Bah ia de Semana 305 AN Caralbe POint 5.0 SA East Kingston 2 520 AN Venezuela Castnes Harbor 0.5 AN Li me Cay 150 SI Islas Los Roques 870 SI Gros Islet Bay 1 05 Mi xed Port Royal 0 CuraGao Mangot Bay 3 145 AN Domin ica n Republic Pl aza Abao 5 0 RS Pet it Tr ou 1 0 Bah ia de Ocoa 2 1250 PL , TH Portanare Bay 35 SI Roseau Bay 3 88 5 SA , TH Boca del Yuma 0 I AN = anchovy (Engraulldae) Soulnere Bay 1 25.5 SI Saona Island 0 DH = dwarf herring (Jenklnsla) Vleux Fort 5 13.5 TH Jamaica PL = pilchards (Harengula) Tobago lime Cay 1 120 DH RS = round scad (Decapterus) Great Courland Bay 10 Long Ba y 1 80 AN SA = sardine (Sardlneita) Man-ol-War Bay 890 RS Negr" Harbor 2 2 .0 AN SI = sllversldes (Athennld ae) Rockly Bay 30 PL Pigeon Island 700 DH TH = thread herring (O p isthonema)
MFR Paper 1084 From Manne Flshenes Review, Vol. 36, No.9, September 1974 Coptes o f th,s paper, In lImIted numbers, are avaIlable from 083, Technt cal InformatIon D,vis,on, Envlfonmental SC Ience InformatIon Center, NOAA , Wa shingto n, DC 20235
MFR PAPER 1085 Donald P. Wagner is an Admin istrative Assistant, Southeast Fisheries Center, National Ma rine Fisheries Service, NOAA , Miami, FL 33149. Robert S. Wolf Resu Its of Troll Fish ing is Staff Assistant for Fisheries, Explorations in the Caribbean Office of Fleet Operations, Na tional Ocean Survey, NOAA, Rockville, MD 20852.
DONALD P. WAGNER and ROBERT S. WOLF Trolling or "towing" as it is gener all y called in the We t Indies involves a moving vessel dragging one or more lin es behind it ; some fo rm of hook and lure combination is attached to ABSTRACT-Exploratory and experimental troll fishing or " towing" was these lin es. The moti on of the lure accomplished by all three project vessels, Alcyon , Calamar, and Fregata, causes the fish to strike it and become during the project period. During most of Phase I (1 966-1969) this effort hooked . The line is th en retrieved, was incidental. In May of 1969 and subsequently, specific cruises were th e fish removed, and the line trailed either wholly or partially devoted to trolling . out again . The method has been In Trolling explorations took place in the waters around Jamaica, around u e for a long period and is today prac the banks north of Hispaniola, throughout the Lesser Antilles, and along ticed in the project region mo tly by the South American continental shelf down to lat.8° 30 ' N. Experimental fishermen on islands possessing narrow work inc luded studies of lure preference; fishing depth; and line materia l, shelf edges. These trolling efforts are length, number, arrangement, and position. Vessel trolling speeds and the conducted almost entirely by very catc h by time of day were investigated. Incidental trolling accomplis hed small boats towing only two to four during Proj ect Phase II is noted. lin es. Summaries of catch rate data show a seasonal availability of troll-caught Prior to the project's efforts, only a pelagic fis h in the eastern Caribbean which begins ve ry early in the year, small amount of offshore trolling using rises to a peak during May, then falls off abruptly until the end of the year. larger vessels had been conducted. Th is tendency is most pronounced on the banks in the northern Leeward Whiteleather and Brown (1945) trolled Islands. Th e total weight of fis h caught during cruises where trolling was six lines from a 77 foot LOA(length a major portion of the effort was just over 28,000 pounds. Blackfin tuna overall) modi fied U.S. west coast purse (Thunnus atlanticus) made up 37 percent of the total, great barracuda seiner in the vicinity of Trinidad and (Sphyraena barracuda) 16 percent, and little tunny (Euthynnus alleteratus) Tobago and obtained good results-up 13 percent. All tunas as a group (blackfin, little, yellowfin, and skipjack) to nearly 200 pounds/hour off To made up over 60 percent of the catch by weight. Trolling has displayed bago. Off Jamaica, Oswald ( 1963) only slight success in harvesting the pelagic resources in the Caribbean. reported catches of up to 200 pounds
35 a d a) ta\..en b\ the J a m 'Hca r I\hen\:\ 01\ 1 ~ l o n \ es\el BIII<'./111 With th e ~ e encouraging rC \Ulh. the a n bbean h ~ h e r\ De\ ell)pment Pn l.1 ect began tro lling act l\ltlcs \\ hlch \\crc o nl\ incidental to l) t hcr fishl ng actl\ I BONE JIG lie 'du n ng the project\ Ph."c I (Il)hh 691. T he rc\Ulh l)f thl\ Incidental trolli ng \\ere summarll\:d b\ 'I e'a\.. 1 (1969) H e reported that .lb,IUt t\\ll third of the Incldcntal trl,11 catl.h \\ as ta \.. en abo\e lat I" and that bl.ldfln tunal accounted Il)r ncarl\ ,Inc-third FE ATHER JIG of all ti h caught Dunng the Ph.!se I penod. the Jamaica r I,hencs L 1\ 1\1 lIn re earch \ es\el BI'lt /111 had Ibscn cd an o\erall catch rate l)f h" pl)unds pcr ti hlng hl)ur dunng nlnt: crul\c III \anl)U~ ban\.. around Jamall..1 Irl'm ugw,t to De ember 196" PLASTIC SQUID At the beginning l)1 the prl).1cct Phase II (eptember 1909 t) Juh 197 I) nll)re emphasl \\ a placcd l)n troll fi hlng T\\o l)blectl\e \\crc set I. To e pll)re. In l)far as p s"bk the project regl)n t) determlnc PLASTIC WORM the a\ ailablllt\ of urtace pelag I pel. e to trL)11 h hlng 2 To e t \anou t\pe and arrangement of trolling gear Fi gure 1 - Ver,ou. lu r .. uud dU ring proleet trolling uplorollon and to determine their effect on Ii h a\ ailabillt) mOl the.ld tJbtlll1.:f \\ erc ,I lltl:U th" e line \lHI"d \t:r the pal d VESSELS AND GEAR Ai< \011\ l)utngg\:r pl,k \ere n c"d e plllrati n f f' 'alC1 OJnd .j / \ Oil In a ImllJr mann"r but \\"rc ~- fu:t " u Id ((\ \ a mJn\ a: II lint: . \\ hlle A II three project \ e ~el \\ ere u ed k)ng Jnd madl.:' III 212-ln"h plpl.:' In m a!t/llWf \\ a IImltcd to ~ line due l() In thl \\or\.. Ca/al/IM and 4ft \ Oil are butt tl tiP and mounlt.:'d alt ,llthl.:' 1,1\:' II.:' thc h,)rt ,Iutrtccer The ngglng u t:d I ter hip built in Japan in 1966! on tl)P III thc bull\,lr\.. Outnggers l)n the e line can bl.:' de cnbed I,)r The e t\\O hip ha\e large \\ell ded.;s de Igncd pecllicalh lor tn,lllng \\crc three ddtercnt arrangcment he hrst and mall tern area Frt'~ala \\a, not fitted on a, "If r r,lm thc Pl)rt arran 'ement \\ a OJ tagllne l)1 "/32- built In England in 196,2 Thl \e el Ide of the \esst:l a 1--fl)l)t b ),'m In " h talnle teel cable fa tened t) Imllar In de Ign to the L. \\ e t whl h h ad been In tailed I,)r 1l1\\lng the l)utrtgger at l ne end and att al:hed coa t almon troller and wa ngged p lan\..t o n net\ \\a u cd In trl)llIng. ll1 a nubber l)1 hl)" curd at the )ther In a Imllar fashion and n the tarb)ard ,Id e . ..I \\ olden end he mainline made ,)1 -Inch All \el;sels were fitted wi th trolling p Ie f ab ut the ., me length \\ a "- urak n) 20 ll1 ~ .:- fa thom lo ng. outrigger that .. aned I n length and fi tt ed Fn~ala a nd Aft \(11/ could ll1\\ \\ J! attached ll1 the nubber b\ a n de ign from hip to hip Frt:~(/I(/' three to four li ne frl) m each of the "- snap >\ leader 01 0045-ln h outrigger were 30 feet long and made pole. \\ hll e a/wllar \\ a li mi ted t) 2-leet ta lnle steel \\ as then att ached up of eCllon of teel pi pe. tarllng two line per outngger to th e ma lnllne \\llh a 4:0 nap \\I\el with a 3 inch pipe at the butt and T hree h) drau li e trolling gurdle termin ating \\Ilh the lure The ec nd tapering down to 1112 inche at the were fi tt ed both po rt a nd tarb ard a nd l e~ t o phl tl ated arrangement ti p . These outrigger were mounted o n Fregalll ln 1970. T\\o fthe po I \\ as a 3 16-tnch pol) prop) lene cord approximately at mid h ip and held on each et were o f 10-lnch diame te r li ed Into th e Itne 3 or 4 feet d \\ n from out by a ti ff arm attach ed between the and one o n each et wa 12 Inch es the outngger. and a 2 fo t teel leader deckhou e and a po i nt about one-third These larger pool were Intended fo r \\ Ith a lure \\ then onne ted to the of the way out from the butt. G uy deep u b urface trolltng. wh ile the m atnltne \\ Ith a nap \\ 1\ el. The e line and a topping li ft were then tandard ize reel were for u rface line \\ere al 0 fr m 20 t 30 fa th m attached close to the outer tip of the trolling . T h ese gurdie were found tn length . The final and what appeared pole and secured fore. aft, and to the to be much lower in retrie ing line to be the mo t efficient li ne riggi ng than the h and-over-hand m ethod a nd con i ted f a length f l.j -inch pol)- 'Scientific name of all fis h represented in exploratory trolling catches are given in were u ed o nl y experiment a ll . Table 2. T he total number of trolling lin e 3 Reference to trade names does not impl) 2 See paper by Wolf and Rathjen, thi endor ement b) the ational M arine Fi h· number, for photographs and pecificati ons. used o n each ve el and the rigging of eries Service. OAA.
36 propylene line extending back from gear experimentation of some sort also trolling, vessel operati o nal limitations, the outrigger to a point in line with took pl ace. Original planning called gear experimentation, and extent of the stern of the vessel. A 4/0 standard for earl y experimental efforts gi vi ng geographical coverage of the region. snap swivel was then attached . From rise to a standard trolling arrangement The units of fis hing effort are the the swivel either the mai nline of 50 that would be used throughout the ship hour and line hour. The former to 500 pound te t monofi lament wa remainder of the work , but due to a is th e number of hours th at the ship fastened or links of 14-inch chain or carcity of fis h cau ght this wa not explored a given area, while the a lead ball was connected between the achieved until near the end of th e latter is the product of the number of tagline and mainline . The chain or ba ll work . ship hours times the number of line was used to carry the lin es sli ghtly Between May 1969 and June 1971 , towed . below the surface. In mo t ca es no most of th e banks and water adjacent RESULTS leader was used ; the lure was attached to islands had undergone some explor directly to the mainline. Stern lines ation into their trolling potenti al. SpeCies Composition The areas explored stretched from were rigged similarly to the outrigger Common and scientific names for lines except that tagline were elimi west of J amaica. east to th e northern a ll species identi fied from tro ll catches nated . Leeward Islands. then south through are given in Table 2. the Windward Islands to about A variety of lures were evalu ated The pecies compositions of th e lat.8 ° 30' . The project region was for uitability in the Caribbean area. catches from a ll cruises where trolling divided into five area for purposes of The e included bone and feat her jig was a major fis hing effort are given in this report (Fig. 2) : of di fferen t ize plu vari ous type Table 3 . In Areas I and II . the pattern of plugs. flasher . spi nner . and plastic l. J amaica south and southwestern waters. is generall y similar. Barracudas domi worm (Fig. I). Mu tad double 2. Waters adjacent to Hispani ola nate the catches in both numbers and hook in izes 4/0. 6/0. and 8/0 were and Puerto Ri co outh to pounds . When the four tuna species u ed mo t of the time. Barbles hooks lat.IS 000' . are grouped together, they comprise 3. The Leeward Islands. were al 0 tried. bu t it wa decided that a good proportion of the total in both too many fi h were 10 t becau e of 4 . The Windward I lands. 5 . Trinidad and the northeastern areas. I n A rea II , wahoo make up them . and they were abandoned after South American helf. about one-fourth of the total weight. a short period . Only artificial lures In Table I. the major exploratory but onl y 7 percent of the numbers. were used in order to make the method trolling effort in ship hours by month This is due mostly to A Icyan cruise free o f the need to divert valu able fi sh and area are gi ven . Area III received the 70- 1 (J anuary) when 17 wahoo caught ing time to obtaining natural bait. No greatest proportion of effort because averaged over 42 pounds each. In as es ment of the effectiveness of arti of the relative succes there. Areas I A rea III , blackfin tuna make up nearly ficial ver u natural lures was made. and IV received high proportions be half of the total catch by weight and On the ba is of the re ult of incidental cause of their proximity to operational numbers. The tunas as a group consti trolling. it was decided to aim our bases (Alcyan in J amaica and Frega ra tute over three-fourths of the total by trolling operations at the tuna group- and Calamar in Barbados). Many fac weight and over 80 percent by num blackfin. little tunny. kipjack, and tors were considered in the planning ber. No other species make significant yellowfin- as representative of th e of a cruise to a particular location. contributions to th e totals. Blackfin most promising portion of the re- Among these were the expected abun tuna make up about one-fourth of the ource. Initial gear arrangements and dance of fis h , results of incidental catch by weight and 30 percent by lure selection were made with this in mind .
SURVEY EFFORT D m The normal technique during a ---~~----r--~~' crui e was to troll along the bank or shelf slopes holding generally to the 100-fatho m depth sounding. Where the edge was precipitous, the vessel ----~----~--~------+-L-~~~------_7--__11r zigzagged on and off th e edge. A small proporti on of time was spent trolling .:-:1· Ii I in very deep water or over the bank proper when conditions (bi rd fl ocks, 1J~I~ etc.) warranted. Whenever concentra tions of fish were encountered, the OUYA~ -I vessel would fi sh the immediate area until biting diminished before con tinuing on. Figure 2.-Cerlbbeen FI.herle. Development Project region ,howlng .re.. where explor.tory During most of the explorations trolling w., conducted.
37 :D () ;>; :D o Glen_-< r(Il ()> :E II) ~ en", ~3~E»~ ~Q; ' ~ 3· II) oO'"-'~c(l) 00 :::rJ:J '0 Q)(O 3 CD '" 0 ~ (3 :::r :J -o~ro-o::J= ~~ 3 0 ... II) c: '" $" ~~m '" o a ? ~ ~;. Q) ~ 3~ ~~;~~ 3 o o ::10 0 _ '" " 0- ,., -. ~ II) c5:J _ :J (I) "'"'" 3 ~~ ~ . -, II) '< o :Ii c.c: _" :J- Table 1.-Shlp hour. 01 ellort expended trolling by area and month. _ 0 :J c: zc. ·1 II) o '" (I) c: '<:J " :J II) o " " II) !! '" 3 ~ Area I Area II Area III Area IV Area V '" 3 Month Year No hrs Month Year No hrs Month Year No hrs Month Year No hrs Month Year No. hrs II) a ~ Oi ~g,P;tT ZO g 0;3 c: 3"0'" "3 :J 0'"_-0 0>- 120 Jan 70 92 May 69 99 July 70 98 Sept 70 22 (I) ",II) O? Sept 69 011) o :J
Tabl. 3.-S~cl •• compo.ltlon of exploratory trolling cnul ... by ar... nd month (Flgurp, In p ••nlh ...... p.rcantag.. . ) ------~--~----~--~--~~~---- Black!ln Little Yellow!ln SklPlack ,Iph n Ra nl ,.... K ,ng ------Cruise Area Month-Year tuna tuna tuna tuna Barracuda (1ISh) runner WahOO mackerel Cero Others Tocal No Lbs No Lb. No Lbs No Lb. . No Lbs No Lb. No Lb. No Lb! NO Lb, No. LbS No LbS No Lbs
A2 69-9 Sept . 69 44 202 9 44 544 73 54~ 16 85 9 47 4 127 2 6 10 199 1.573 AS9-10 Oct. 69 27 107 16 4 45 135 715 40 11 47 1 30 18 10 205 1 014 A70-2 Feb. 70 2 14 22 148 6 54 30 216 Totals 73 323 5 25 48 589 23-0 1450 20 1~5 20 94 11 ~1 1 3 11 24 20 43J 2,803 ~ QC Percent (168) (115) (1 2) (0 1) (11 1) (210) (53 a) (501) (46) /441 (46) (34) 125) (75) (0.7 (0 J) (55) (O .:j (1000) (100 01 A70-1 II Jan . 70 37 269 6 22 5 132 1 207 12 123 23 17 715 2 4S 11 84 6 28 228 2.521 A70-11 II Nov. 70 12 131 6 24 38 39} 18 75 1~ 60 3 55 1 J 5 21 95 ,62 A71-4 II May-Jun 71 11 72 5 23 14 82 6 101 154 1 6 3 13 36 ~ 48; Totals 60 472 17 69 1 5 184 - 1681 36 29\f 16 83 2, ~ - 3--- 51-- 15 101 18 85 3,. 3,170 Percent (15.9) (12.5) (4.5) (18) (0 3) (0 t) (488) (4J 6) (95) (7 9) (42) (22) (72) (2J 5: (08) (1 41 (J 0) (2., (J 8) (23) (1000) (100 0) C 269-S III May 69 639 4506 299 1226 3 1 898 16 75 37 111 35 497 13 56 3 25 19 151 10 JJ 1 102 7.589 C69-9 III Aug . 69 227 1262 64 280 6 31 125 24 60 3 21 18 1'4 3 105 2 22 8 6 33 380 2 016 A69-11 III Nov. 69 8 53 7 30 1 8 14 70 3 1'1 3 125 1 10 3i 309 F370-11 III Dec . 70 75 436 63 285 3 19 26 26t , 3 6 2 20 8 23 l.g 1.053 F71-2 III Mar 70 161 1021 195 780 2 12 53 ')06 32 296 n 86 20 1 2 28 9 J 1 J 19 J86 2 ;80 C71 -6 III Apr 71 200 526 55 223 41 t 5 32 159 14 199 8 31 4 22 J HI 1 206 C71-8 III Jun 71 268 1426 134 596 47 587 49 437 60 304 t 3 78 440 10 311 18 ~6J 9 43 I 6,5 4 .4 1, Totals 1578 9230 817 3420 84 1532 103 681 "" 220 - 1010 ttJ 1290 1'J6 710 27 173 48 SI-6~~31 1J9"-- ·10 593. 1.819.3.0 Percent (49 7) (477) (25 n (17 7) (26) (79) (32) (35) (69" F70-7 IV July 70 13 87 15 195 FlO-8 IV Sept. 70 1 10 102 F70-1O IV Nov. 70 29 139 26 3 9 22 300 F71-1 IV Feb. 71 9 32 12 1 9 32 235 F71-3 IV Mar . 71 31 222 9 55 13 77 18 3 7 55J F71-4 IV May 71 4 4.3 558 Totals 82 480 5 23 Hi 81 ~ I 19 3 :83 1 944 Percent (29 0) (24 7) (18) ( 1.2) (5 n (421 (10) (I II 0" (100 0) (100 OJ F70-8 V Sept . 70 J 1 3 F70-9 V Oct. 70 6 17 1 15 97 :'>3 1:'3 F71-1 V Feb . 71 1 3 2 13 lJ 1; 1 Totals 7 20 "3 15· • u- 38 29; -;< orr """1\ ----.." (10001 (100 OJ Percent (184) (67) (79) (5 1) ---&-. ----r. Regional Totals 1800 lC1525 847 3552 100 1613 170 t 37 58 55 26t 55 1<1 J 310 28 lB4 Percent (41.8) (37 .3) (197) (126) (23) (571 (39) (49) (2 t) (131 (091 (13' o 6) (100 01 (1000
' A = Vessel Aleyon 2C = Vessel Ca/amar 3F = Vessel Fragale Table 4.-Catch rate in pounds per trolling hour and pounds per line per hour by cNlse. area. and J amaica (A rea J) during September month. and October 197 I, complete records Pounds Ship on the catch of various types and sizes of troll in g Lbs! of lu res were kept. Red/white and Cruise Area Month-Year fish hours Line hours Lbs!hour Ltne hour yell ow/white feather jigs were com A 69·9 Sept. 69 1.573 120 788 13 .1 20 ' A69-10 Oct. 69 1,014 124 744 8.2 1.4 pared with bone j igs and plastic bodied A70-2 Feb 70 216 17 108 12.7 20 and skirted squids. In Table 5 the lure Total 2,803 261 1,640 10.7 1 7 A 70-1 II Jan . 70 2,521 90 529 23 .0 48 preference data are su mmarized . Over A70-11 II Nov. 70 762 39 213 19.5 2 .8 all , red/white feather jigs were fo und A71-4 II M ay-Jun 70 487 76 702 6.4 0 .7 Total 3,770 205 1,444 18.4 2 .5 to be su perior to the other types used. C269-5 III M ay 69 7,589 99 592 76 .7 12 .8 Consideri ng the most numerous spe C69-9 III Aug . 69 2,016 99 594 20.4 3.4 A69-11 III Nov 69 309 27 169 11.4 18 cies as separate groups the barracuda F370-11 III Dec 70 1,053 97 970 10 .9 1.1 F71-2 III Mar 71 2,780 125 1,250 22.2 2.2 were nearl y evenly divided in prefer C71-6 III Apr 71 1,206 30 150 40 .2 8.0 ence between yell ow/white feat her jigs C71-8 III Jun . 71 4,417 151 1,057 29 .3 4 .2 Total 19,370 628 4,782 308 4 1 F70-7 IV July 70 195 98 490 2.0 0.4 F70-8 IV Sept 70 102 91 637 1.1 0 .2 F70-1O IV Nov 70 300 97 970 3.1 0.3 Table 5.-uJre type preference. F71-1 IV Feb 71 235 84 840 2 .8 0 .3 Numbers of fish caught F71-3 IV Mar 71 554 78 780 7 .1 0 .7 F71-4 IV May 71 558 59 590 9.4 0 .9 Red! Yellow! Total 1,944 507 4,307 3.8 0.5 White White FlO-8 V Sept 70 3 22 144 0 .1 0.07 Fish feather feather Bone PlastiC F70-9 V Oct 70 123 75 525 1.6 0.2 Species Jigs Jigs Jigs squ,ld F71-1 V Feb 71 171 19 190 9.0 09 Total 297 116 859 2.4 0 .3 Barracuda 56 46 59 9 Blackfln Regional total 28 , 184 1,717 13,032 16 .4 2 .2 tuna 45 9 10 2 'A - Vessel A /cyon 2C - Vessel Ca/amar 3F - Vessel Frega/a Skipjack tuna 29 5 6 Little nu mber in Area IV. T he tuna group tuna 3 Rainbow is about equal in weight contribution 12 .0 e_. ARfAm: runner 11 4 3 1 to that of wahoos, but they contribu te Dolphin 11 1 1 3 Jacks 5 3 a much greater number. Barracuda Mackerels 2 1 10.0 Wahoo 3 are the most numerou specie. From Total the relatively few fis h caught in Area fish 165 73 80 21 B.O • V, barracudas are again most numer Hours a: :::> trolled 323 .5 172 .8 23 1.6 71.3 ous, but are about equal in weight 0 ::t: 6.0 All fish ! w 0.42 0.35 to dolphin fish . Wahoo again make z hour 0.51 029 ::; Barrac uda! up an important proportion of about a: w hour 0. 17 0.27 0.25 0 .13 one-fourth of the weight. Since the 0.. ' .0 ...... Al l tuna! regional total are so dominated by '" hour 0 .24 0.09 0.06 0 . 11 catches from A rea III , a re ume of ~ 2.0 . ., pecies composition for the region a ." x'" x __x _ x and bone jigs, but di played a definite a whole is meaningless. 0.0 ,- '-- . F M A M J J A SON 0 lesser preference for red/white feather Catch Rates MONTHS jigs and plastic squids. In contrast, T he troll ing catch rates in pounds/ Figure 3.-Trolling catch rate variation by the tunas as a group overwhelmingly month. ship hour and pounds/li ne hour are preferred red/white feather jigs. given in Table 4 . The highest catch available fo r A reas III and IV only, When examining the catch of barra rate was observed on Ca/all1ar cru ise but both refl ect th e same general cudas and of all tunas by lure size 69-5 in A rea III duri ng May 1969 pattern of hi ghest avail ability duri ng (see below), it is evident that when when nearl y 77 pounds per sh ip hour the second quarter of the year and barracudas took feather jigs they pre and 13 pounds per li ne hour were relatively low levels during the firs t, ferred the larger size. while the tunas caught. Area III displ ayed the highest third, and fo urth quarters. preferred the smaller, consistent catch rates and also th e 3 ounce feather Jig 6 ounce feather Jig Gear Experimentation Barracuda 0.09' 0.45 highest average at about 3 I pounds All tunas 0.32 0.19 per ship hour. The average catch rate Duri ng most of the trolli ng explora 'Number of fish caught per lure!hour of trolling observed in Area III was in excess of ti ons various ki nds. lengths, and the rates observed on any cru ise in any arrangements of troll ing lines and During cruises conducted by Fre of the other areas. types and sizes of lures were tested gala in 1970, attention was paid to lure When the catch rates are pl otted to evalu ate their effect on catch rate. preference, but results were inconclu by the month when they were observed sive due to a scarcity of fish caught. Lure preference an indicatio n of seasonal avail ability Beginning with cruise 70-II , Fregata is obtained (Fig, 3). Sufficient data to During A/cyon cruises 69-9 and used all small sized red/white or a ll present a seasonal evalu ati o n were 69- 10 conducted on the banks around white feather jigs during nearly all the
39 subsequent trolltng cr ul 'c~. T hc dccl o thcr th an tun", \\t:re mnre randoll1 down to as short as '\ fa th oms fro m sion v, a~ based on their perlormancc and \-\ ere prohahh the resul t 0 1 the stern. I he,e \-Mlahlc line le ngth, \\lth the tuna group dunng pre\ll)u, laclOrs o th er than the numher lI f lines ,t1l ov,ed an Increase In the numher 0 1 Altyol/ \-\orh. and the prcierence of a tov, ed Iincs tllwed wh il e decre,ISlng line loul commcrclal tuna troll fl,herman n)n Ing prohlem, hut ,tlil rcl,tlnlng ci.l((;h sultant to the pro,lect fn)m the v,e,t l llle length Ing I.'Illc lenC\ T he longer lines ci.lugh t coast of the Lnlted State, 1 h" pattern sels \-\ere uSing trlllltng hnes llf m)t d 1,lrger nUJl1her nl Ihh 111 Mea, 01 low v, as \aned onl\ \.) nce dunng tv,o da\,' less than 2'i fathnms \\'hen nwre th,1Il prodULlI\II\ In that thc ()cca\lonal fishing on Fr<,,,:olil crul,e 7 1- \. \\hen SI' lines \-\ere streaJl1ed these hdd a ,tn\..e v,ould he on the longer IlnL"i, v,hite plastic \\orms v,ere dlrecth tendene) tl) crnss and It)ul dunn!.! a hut In .JfCi.l' 01 fish concentrations c\.)mpared \-\ Ith \\ hlle feather Jig, '1 he turn T hrnugh e perllllent INumber of fish caught per ure/hour tro.long Agalll feather Jigs \\ ~rc ,h\.)\\ n tt) he leo the most effect" c ~ F.bru.ry = March April 170 Jun. = -[> Trolling line variations Tot.tMO = - 160 ~I atenal.-1\1 onofllament Itnes \\erc found to bc n1l.1 , a tl,lac tor) The) crcatcd Ie,s drag than 150 braided co!t\.lI1 \.)r s\ nthetlc Itne \.) 1 comparable trength. \\ ere more dl fti 10 1'0 .... I r cult for ft . h to sec 111 thc \\ater. had .!) :> ~tnh.e ... built-In hoch. ab \.)rptl\.)n and 130 u a greater rangc of breah.lng trength, r ....r ~ \\ ere readll) a\ ai lable OnL d "ad\ an z ... 060 120 ... tage \\as that monofilament \\ a more ::E a >- dIfficult to hand-retrte\e than a largcr CD '"...... ,/ «.... diameter line \\ould ha\e been r 1\ ! ....a E'\penence sho\\ed. hov,c\er. that Ih :>'"... u ad\ antages conslderabl) out\\ clghed r 50 1 I \!f "~ its disad\antages. 1;:'" lL ,I I :\ ' a , I, l'-;umber of line .- During this \\orh. a: , I w CD I i \, there v,ere no specific e:-..penmenls ::E , , ,I aImed at determining the effect of a ~ 40 I ..... , ,I diffenng number of trol ling lines on ....« , <;]1 I a , the catch rate Although the number .... , of lines used b) an) of the \essel did / I \ ar) somewhat, the change u u all) I, \\ , I I 30 took place bet\\ een cruise a nd no t I ; ,/ 40 In late 1970 a nd on Frega{(l crui se Line Location.-During Frega{(l 10 lines during the cruise. T his is an 7 I-I. cruise 7 1-2 when the arrangement of indication . at least. that there is some Line Length lin e lengt hs o n each side of the vessel effect on the position of the tro lling Cruise 3-10 11 -20 21-30 31 + was the same and a ll lin es u ed the fathoms fathoms fathoms fathoms line in the arrangement. 71-1 244' 69 .3 740 same lure (red/white feather jig - I V2 71-3 8.4 7.2 50 o unces); there was a decided superi or Vessel speed 'Number of fish caught per line it y in th e catch by lines on the port No direct o bservati o ns were made side of th e vessel over lines on the of the effects of vessel speed on catch . When cruise 71-2 was completed. starboard sid e. the resu lts showed a higher catch rate Incidenta l trolling was always con Rati o ducted at the vessel's cruising speed. for lines in the 11-20 and 21-30 (port to fatho m length range. The line a rrange Species Port Starboard starboard) while regul ar expl o ratory trolling was Barrac uda 40 18 22 1 ' all done at about 6 knots. This speed ment wa altered for c ruise 71-3 when All tu na 225 127 1.8 1 Other species 40 28 1 4 ' 1 was considered adequate for tuna lines of under 10 fathoms were elimi Total 305 173 1.8 1 nated a nd lines in excess of 30 fathom species. but not so fast as to preclude 'Number of fish caught added. The results during cruise 7 1-3 catching other species. show an a lm ost even distribution of Line Arrangement.- During Fre catch between the three length groups ga la cruise 7 1-2 the two 2 I-fathom Time and this length arra ngement was used lines located o ne in from the end of On all tro lling crui es in 1971. by all vessels througho ut the rema in each trolling outrigger caught nearly detai led reco rds were kept for the der of project tro lling explorations. one-third of a ll the fish caught by all time of day when fis h were caught. T hro ugh these observations. it was establi shed during what period(s) of 70- the day the greatest fish biting activity LEGENP: was encountered. It would be pre '\ Gibbs S..mounl sumptuous to state the periods of Ar •• m minus S.omount=-- : \ I \ greate t fish activity for all area due I \ to the sparseness of data taken as to I I \ time of day; however. Area III (north , \ ern Leeward Islands) appears to have I \ I \ enough data to produce a reliable I \ picture of greatest fish activity. f \ As can be seen in F igure 4. there are I 50- I \ two periods of increased fish biting I, I \ during the day ; one in mid to late I , \ I , I \ morning a nd another in mid to late I \ .... \ afternoon . which is more pronounced. x I \ 41 out ra pidly. Fi gure 5 shows a pi cture 100- LEG€t<) : of G ibbs Seamount data with greatest --- =Blac kf,n TunD fis h acti vit y in th e mo rning between l - x- = Llltlq TunD I 1000 and 1200 hours. A rea III is a cruise; however , there were places Pounds LIne Calch rate where th e rate was hi gher. Specific Area Location Mo nth c aught hours (Ibs ./ 11 ne/hou rJ locations where catch rates in I M orant Cays - South 01 Jamaica Sept. 693 108 6.4 excess of 5.0 pounds/l ine hour were II S.E. M ouc h olr Bank - N orth of Hispaniola Jan 1.100 90 12 .2 II S. Mouch oi r Bank - North of HispanIOla Jan . 5 12 72 7 .2 observed are given in T able 6. It III S.E. Anguilla Bank - Northern Leeward Is. May 5, 196 378 13.7 should be remembered however, that III N. Anguil la Bank - Northern L eeward Is. May 656 66 9.9 III N.E. A nguilla Bank - Northern Leeward Is . May 702 60 11 .7 in most cases each of these locations III N. Saba Bank - Northern Leeward Is . April 1,099 140 7.9 III Gibbs Seamount - (16° 32 ' N.- 42 Aue nced by the effect of vessel a nd day the fish are most li kely to be types of fishing. it caf'\ be a good second crev. turbulence. The positive factors caught trolling could be applied if ary method during slack periods of v. h ic h appear to affect catches all troll ing were to be combined with handlining (mechanical reel) and have the effect of minimizing turbu some other fi hing operation. i.e .. trap fishing for snapper and related lence in the area of the lure. With handlining or trap fishi ng. which specie. longer lines fi hed farther out. the could be conducted during the off effect i ob\ iou . Wh) catches should peak trolling time . be better on the Ie s turbu lent port In ummary. troll fishing ha dis LITERATURE CITED side of the \essel is not ob\ious until played onl] slight uccess in harvesting OS" ald. E. O. 1963 . Developing an off shore fishery In J amaica. Proc. Gulf the effect of a right hand turning the urface pelagic re ources of the Canbb. FI h. Inst. 15: 134-139. Oswald. T.. J. Garner, and K . KawaguchI. propellor creating more turbulence on project region . Only the banks of the 1969. Report to the Government of St. the right or tarboard ide of the \essel northern Leeward Islands. and these Kilts. Ne\ is and AngUilla on Explorator) and Expenmental Fishing Around St. is remembered . o nl) during April a nd May. provided Kilts and Nevis. FAO. Rome. The idea of Ie s turbulence-more catch rates con idered high enough Whlteleat her. R. Too and H . H. Brown. 1945. An experimental fishing survey In opportunit) for fish biting-is ~trength to support troll fi hi ng as an i ndepen Trinidad. Tobago and Bntish Guiana. ened b) the inboard line during a dent effort. As the method is already AnglO-American Canbbean Comm iSSIOn. .S. GO\. Pnntlng Office. Wash .. 130 p. turn tending to catch more than the knov.n in the We t I ndies and relative Yesakl, M. 1969. Troll Fishing Catches in the Canbbean Sea and Adjacent Atlan other because the) are in ide the I) ine\pen ive. if a \e el mu t travel tiC Ocean. U DPIFAO Caribbean Fish \e el' turning Circle and v.ake and to SUit able offshore grounds for other enes Development ProJect. (Mlmeogr.) the re ultant turbulence . Thi i 0 e tabli hed that our trolling \e el MFR Paper 1085. From Marine Flshertes Review, Vol. 36, No.9, often zigzag v.hen in a chool to September 1974. CopIes of this paper, in limIted numbers, are avaIl Increa e catche . able from 083, Techntcal InformatIon D,vis,on, Environmental The value of kno'Wing what time of SCIence Information Center, NOAA , WashIngton, DC 20235. MFR PAPER 1086 Geoffrey R. Chislett, c/o Goddard, Apt. 107, 1720 Larch Street, Vancouver g, British Columbia, Canada. Mitsuo Yesaki, c/o Sudepe/PDP, Rio Spiny Lobster Fishing Explorati ons Grande, Rio Grande de Sol, in the Caribbean Brazil. GEOFFREY R. CHISLETT and MITSUO YESAKI 197 I. Good incidental catches of lob ters during fish-pot fishing explor ations in these areas and the high ABSTRACT-The Caribbean Fishery Development Project vessel Alcyon economic demand for their meat were devoted four cruises toward assessing the spiny lobster resources of the primary reasons for this work. but Pedro Bank and other small banks south of Jamaica; Mouchoir, Silver, and the high success of recent exploratory Navidad Banks north of Hispaniola; Saba, Anguilla, Barbuda, and other fishing survey off H onduras and small associated banks in the northern Leeward Islands. This work was Nicaragua (Yesaki and Guidicilli2 ) v. as undertaken as a consequence of good incidental lobster catches having also considered. I t was decided that been made dunng pot fishing explorations for snappers and related the exploratory techniques (including demersal species in the northern half of the project region. echo ounding, trawl netting. and pot The exploratory technique applied consisted of an echo sounder survey fishing) u ed during this latter 'Work of the bottom followed by try net trawling to assess the abundance and would be experimentally attempted in locate areas of concentration, after which lobster pots would be set to our project region. obtain catch rate data. The try trawling was abandoned after one cruise Some exploratory lobster fishing had because of generally unsuitable trawling grounds in the places explored. been conducted earlier in other parts Fis h po ts were also set alongside lobster pots on occasion for comparison. of the project region. During a gen Lobster catches were extremely low and only the western end of Pedro eral resources survey of Tri nidad and Bank displayed commercial potential with a catch rate of 0.45 lobster Tobago by MY Fregara in 1968, per pot. a total of 144 lobster pot sets and 8 ice-can sets were soaked an average of 52 hours but yielded no lob ters. INTRODUCTION the abundance of spiny lobster l (Pallu lirus argus) in the northern half of the 2 Yesaki, M., and M. Guidicillt. Summary of exploratory fishing operations of the RV The Cari bbean Fishery Develo p project region , from February to July CanoplIs in the western Caribbean Sea to ment Project devoted four explo ra June 1970. UNDP/FAO Central American I Referred to hereafter as spiny lobster or Fishery Development Project, 46 p. (Unpubl. tory/experimental cruises to assessing lobster. manuscr.) 43