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Viele wan 2 pie ete 6 Atte purer FM ee ey PUPP? ne oot mieten eee SOW Re ete ito Patt eowhp BVT op ar ees eet A Pe Waser ee pior Fe he tne eae eas Mey gee Pe eee a gay uated gt Peas + 5 te eg ee pent FO eS ee wie csee Kaew spe DP ite*er ws ae > Ws FV Hye PAS HARVARD UNIVERSITY e Library of the Museum of Comparative Zoology maa» >4 rn, ‘702 NOAA Technical Report NMFS SSRF-702 Length Composition of i Yellowfin, Skipjack, and 4, wp Bigeye Tunas Caught in ” States of ™ the Eastern Tropical Atlantic by American Purse Seiners < ae ic, * a0» Gary T. Sakagawa, Atilio L. Coan, and Eugene P. Holzapfel August 1976 U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Marine Fisheries Service NOAA TECHNICAL REPORTS a National Marine Fisheries Service, Special Scientific Report —Fisheries Series | The major responsibilities of the National Marine Fisheries Service (NMFS) are to monitor and assess the abundance and geographic distribution of fishery resources, to understand and predict fluctuations in the quantity and distribution of these resources, and to establish levels for optimum use of the resources. NMFS is also charged with the development and implementation of policies for managing national fishing grounds, development and enforcement of domestic fisheries regulations, surveillance of foreign fishing off United States coastal waters, and the development and enforcement of international fishery agreements and policies. NMFS also assists the fishing industry through marketing service and economic analysis programs, and mortgage insurance and vessel construction subsidies. It collects, analyzes, and publishes statistics on various phases of the industry. Lia's Pay. The Special Scientific Report—Fisheries series was established in 1949. The series carries reports on scientific investigations that document long-term continuing programs of NMFS, or intensive scientific reports on studies of restricted scope. The reports may dea! with applied fishery problems. The series is also used as a medium for the publication of bibliographies of a specialized scientific nature. : ‘ NOAA Technical Reports NMFS SSRF are available free in limited numbers to governmental agencies, both Federal and State. They are also available in exchange for other scientific and technical publications in the marine sciences. Individual copies may be obtained (unless otherwise noted) from D83, Technical Information Division, Environmental Science Information Center, NOAA, Washington, D.C. 20235. Recent SSRF's are: 619 Macrozooplankton and small nekton in the coastal waters off Vancouver Island (Canada) and Washington, spring and fall of 1963. By Donald S. Day, January 1971, iii + 94 p., 19 figs., 13 tables. 620. The Trade Wind Zone Oceanography Pilot Study. Part IX: The sea- level wind field and wind stress values, July 1963 to June 1965. By Gunter R. Seckel. June 1970, iii + 66 p., 5 figs. 621. Predation by sculpins on fall chinook salmon, Oncorhynchus tshawyt- scha, fry of hatchery origin. By Benjamin G. Patten. February 1971, iii + 14 p., 6 figs., 9 tables. 622. Number and lengths, by season, of fishes caught with an otter trawl near Woods Hole, Massachusetts, September 1961 to December 1962. By F. E. Lux and F. E. Nichy. February 1971, iii + 15 p., 3 figs., 19 tables. 623. Apparent abundance, distribution, and migrations of albacore, Thunnus alalunga, on the North Pacific longline grounds. By Brian J. Rothschild and Marian Y. Y. Yong. September 1970, v + 37 p., 19 figs., 5 tables. 624. Influence of mechanical processing on the quality and yield of bay scallop meats. By N. B. Webb and F. B. Thomas, April 1971, iii + 11 p., 9 figs., 3 tables. 625. Distributionof salmon and related oceanograpic features in the North Pacific Ocean, spring 1968. By Robert R. French, Richard G. Bakkala, Masanao Osako, and Jun Ito. March 1971, iii + 22 p., 19 figs., 3 tables. 626. Commercial fishery and biology of the freshwater shrimp, Macrobra- chium, in the Lower St. Paul River, Liberia, 1952-53. By George C. Miller. February 1971, iii + 13 p., 8 figs., 7 tables. 627. Calico scallops of the Southeastern United States, 1959-69. By Robert Cummins, Jr. June 1971, iii + 22 p., 23 figs., 3 tables. 628. Fur Seal Investigations, 1969. By NMFS, Marine Mammal Biological Laboratory. August 1971, 82 p., 20 figs., 44 tables, 23 appendix A tables, 10 appendix B tables. 629. Analysis of the operations of seven Hawaiian skipjack tuna fishing vessels, June-August 1967. By Richard N. Uchida and Ray F. Sumida. March 1971, v + 25 p., 14 figs., 21 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 630. Blue crab meat. I. Preservation by freezing. July 1971, iii + 13 p., 5 figs., 2 tables. II. Effect of chemical treatments on acceptability. By Jurgen H. Strasser, Jean S. Lennon, and Frederick J. King. July 1971, iii + 12 p., 1 fig., 9 tables. 631. Occurrence of thiaminase in some common aquatic animals of the United States and Canada. By R. A. Greig and R. H. Gnaedinger. July 1971, iii + 7 p.. 2 tables. 632. An annotated bibliography of attempts to rear the larvae of marine fishes in the laboratory. By Robert C. May. August 1971, iii + 24 p., 1 appendix I table, 1 appendix II table. For sale by the Superintendent of Documents, U.S. Goverment Printing Office, Washington, D.C. 20402. 633. Blueing of processed crab meat. II Identification of some factors involved in the blue discoloration of canned crab meat Callinectes sapidus. By Melvin E. Waters. May 1971, iii + 7 p., 1 fig., 3 tables. 634. Age composition, weight, length, and sex of herring, Clupea pallasii, used for reduction in Alaska, 1929-66. By Gerald M. Reid. July 1971, iii + 25 p.. 4 figs., 18 tables. 635. A bibliography of the blackfin tuna, Thunnus atlanticus (Lesson). By Grant L. Beardsley and David C. Simmons. August 1971, 10 p. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 636. Oil pollution on Wake Island from the tanker R. C. Stoner. By Reginald M. Gooding. May 1971, iii + 12 Be 8 figs., 2 tables. For sale by the ov Superintendent of Documents, U.S. ernment Printing Office, Washington, D.C. 20402. 637. Occurrence of larval, juvenile, and mature crabs in the vicinity of Beaufort Inlet, North Carolina. By Donnie L. Dudley and Mayo H. Judy, August 1971, iii + 10 p., 1 fig., 5 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 638. Length-weight relations of haddock from commercial landings in New England, 1931-55. By Bradford E. Brown and Richard C. Hennemuth. August 1971, v + 13 p., 16 figs., 6 tables, 10 appendix A tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 639. A hydrographic survey of the Galveston Bay system, Texas 1963-66. B E. J. Pullen, W. L. Trent, and G. B. Adams. October 1971, v + 13 p., 1 figs., 12 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 640. Annotated bibliography on the fishing industry and biology of the blue crab, Callinectes sapidus. By Marlin E. Tagatz and Ann Bowman Hall. August 1971, 94 p. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 641. Use of threadfin shad, Dorosoma petenense, as live bait during experi- mental pole-and-line fishing for skipjack tuna, Katsuwonus pelamis, in Hawaii. By Robert T. B. Iversen. August 1971, iii + 10 p., 3 figs., 7 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washing- ton, D.C. 20402. 642. Atlantic menhaden Brevoortia tyrannus resource and fishery—analysis of decline. By Kenneth A. Henry. August 1971, v + 32 p., 40 figs., 5 appendix figs., 3 tables, 2 appendix tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 643. Surface winds of the southeastern propical Atlantic Ocean. By John M. Steigner and Merton C. Ingham. October 1971, iii + 20 p., 17 figs. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washing- ton, D.C. 20402. 644. Inhibition of flesh browning and skin color fading in frozen fillets of yelloweye snapper (Lutzanus vivanus). By Harold C. Thompson, Jr., and Mary H. Thompson. February 1972, iii + 6 p., 3 tables. For sale by the Superinten- dent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 645. Traveling screen for removal of debris from rivers. By Daniel W. Bates, Ernest W. Murphey, and Martin G. Beam. October 1971, iii + 6 p., 6 figs., 1 table. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington D.C. 20402. 646. Dissolved nitrogen concentrations in the Columbia and Snake Rivers in 1970 and their effect on chinook salmon and steelhead trout. By Wesley J. Ebel. August 1971, iii + 7 p., 2 figs., 6 tables. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington D.C. 20402. 647. Revised annotated list of parasites from sea mammals caught off the west coast of North America. By L. Margolis and M. D. Dailey. March 1972, iii + 23 p. For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Continued on inside back cover. ee Oy Pn 4 My > A ve i Ce LwuiS" li, nal \ONA; \" No; O S eS C6 ‘’, N = we Ms fe) te) + » y m 2 =] o) “A ig) NOAA Technical Report NMFS SSRF-702 Length Composition of Yellowfin, Skipjack, and Bigeye Tunas Caught in the Eastern Tropical Atlantic by American Purse Seiners Gary T. Sakagawa, Atilio L. Coan, and Eugene P. Holzapel August 1976 U.S. DEPARTMENT OF COMMERCE Elliot L. Richardson, Secretary National Oceanic and Atmospheric Administration Robert M. White, Administrator National Marine Fisheries Service Robert W. Schoning, Director 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 NMFS 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 NMFS publication. Page EN I ne NS at) Sea ae, 6 MS Sh toe bo ee ht Meee doe. 1 rr Mn Set ee Cee A. eS hei ot oA ETM, So. ke Gil <. bP OIE Als OR. 1 Crean ers. ek ye ee RR A ete ee EO” oe td Tees. oo. 2 enn Mem AATeA-MOnbiet 6: Feith) > tis, oR Pod lag Boek 2 om boas. we deied 63 2 0 A oe FT aon an a ia aah ice Lurie el. il wen, ae 2 Carers Sane SHR. ot Sosred cm! aledd’s. ws. culls eenfees.8 ao bee. 2 2 Of. 2 URS a re. eee) en, ee 2 BArEBAbes ene uarcomposivon ofveatch® “2 Adare Jefe) Soekics © ee tes cee Gelergne oo 3 Pi ae ee MCs eOImpoOsitiogn Of .CALCHES) . . =... 6 2 << % so. «s« ee ~ oOUlmi viteettsé Jeske... 5 ner e Wii. Usted, sh styieds nce). avelaida kb .calsionened. digcet bade. 5 aes MERE Seer a acca, oi, gC WR Ss a ws & ov OK 4 ee Gant. 6 6 inn errr. genie: fencer A. sth dienes wear. religida. ko noldempeum. dighsl, beleatid © ¢ a PERN MIDLER IMINALES Mri.) Ses ge 8 Gene mes we oN 28 bow 3 we S eB fa aneke as « 9 nate nmmErree Meee seen). Ye “Dees aN. acids. Yh ok wie ae. OR borer. 9 a RENE aa hos os i vine) @ one wh. Sie me's a: ws oe SA tn ey OEE 9 Fen ERR, MRC AS ot) sores acts «. SMG Ac ie RISO MET le WME MRSS <8 9 ee a ere Ee wali: Tair dls fe. atigndis tne Seat aS. Goan oad Sot eRe Rie A leakeRh.. ss 11 i CiCiner weres mnie ees. wt Mineo cue). dosterde. Wo sdendomsews. argent, Gases’. 11 en SEER TE am i sk a ei we le ew apn w » RPO Sede leeks. 11 Figures 1. Map of the eastern tropical Atlantic where American seiners fish for tropicaltunas .............. 2 2. Estimated length composition of yellowfin tuna caught by American seiners in the eastern tropical RNS MRS CRO 1S 2 ac BP sas in (6/2). SS Ggus, sige Lev ar AT ourirGy wisehpmaier le eet ea adie oe Welk Some an gee as 6 3. Estimated length composition of skipjack tuna caught by American seiners in the eastern tropical FN ARNE TCR ONS 11 REM essa fo: eagte Yeh ve. “e\ o's) gh ce- 5, ay gb. Ge aie beige ve ee Gh Dae pee Se ee anes 7 4. Estimated length composition of bigeye tuna caught by American seiners in the eastern tropical Pati AEG CME NTO RATICL ipl Armee en) SoS cae tee Mal Suseh ey epee ae ONS, oe, Ga Re AC oT ogee een Sas 8 5. Estimated length composition of yellowfin tuna caught in August 1973 in NMFS area 52 ........ 9 6. Estimated length composition of yellowfin tuna by month caught by American seiners in 1970 ...... 10 7. Estimated length composition of skipjack tuna by month caught by American seiners in 1970 ...... 11 Tables 1. Catch (metric tons) and number of length-frequency samples of yellowfin tuna by NMFS area-month strata. Samples substituted in strata without samples are identified in parentheses ........... 3 2. Catch (metric tons) and number of length-frequency samples of skipjack tuna by NMFS area-month strata. Samples substituted in strata without samples are identified in parentheses ........... 4 3. Sampling coverage of NMFS area-month strata in which yellowfin and skipjack tuna were caught by PACHCANSGUMALSCINELS INV LOOS-04. cA agcue cil ere ee fe ee ea ee, SE ee Sees 5 4. Estimated age composition of yellowfin tuna caught by the American purse seine fleet in the eastern EEO PICA MAA GI COME Ae ee ca odes a) cose dae cp seis) See Oe ee etree, © Oe, ET LS 7 5. Estimated age composition of skipjack tuna caught by the American purse seine fleet in the eastern EEO PICRUPAULATI EI CMe yk ahs wren 6 asc. 5p eee a ete SL oe cle eee ae SE ee oe Le len 7 6. Catch and number of length-frequency samples of bigeye tuna caught by the American purse seine fleet INETHETCASLEFHGCLODICAIWAUIADUIC: 2.5) 4. ensae ons wep ee ee Tete ae Dee oe eh SOUR AE 8 7. Number of NMFS area-month strata in which single samples were obtained or substituted ....... 10 Appendix Tables 1. Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern ELOPICAIPATIANLICEIN EG OOO EER AN EAM ne eae Seay aie teen Tee GS 3,°5 Wiusplen se sasoe ote nee ees, Ss 13 2. Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern iEODICAIBA LI ATILICHHI Dl OOO MM Nral eae eePEs PR noms ecec sae f,G che eece ea) 6 ug «ss ese es See ee 13 3. Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern PLODICH AT ARI CEITIO OO meteme Mtr erm ence ce nda cee wep creas O cujece ela es, Ss fe sure. ce em 14 Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern tropical Atlantic in 1971... s. ce ee om whe 0, os eis SUR, 9) a ee 15 Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern tropical Atlantic in 1972 |. «a 0s ee 8 © ee ee ow Oe alee oh ah eee geen ee 16 Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern tropical Atlantic in 1973... 5. a 2 ees we 8 ow we eee © lg got oe RII ne eee 17 Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern tropical Atlantic in.1974 2.1... ss « se we © ww ee mw Be Mo ome meee alcp tenn ee 18 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1968...» . +.» © © we ew em op oe ee tee wea mo een 19 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1969... 2 6s a ee cw hw wi ow mo A Fe En eee 19 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1970 6 6 cn. ho ee Asta a Se lee hr aed tee red alate ee 19 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1971 2 6 woe nee wh wt km ew Oh oh th GSS ol ny oO ee ee 20 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic. in 1972 .2sce.. see. &) oe ee eee es ee eee 20 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantie’in 1973 ln. eS. ae Ee PO ee ot en ee 21 Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1974" 2 oo. a ea cee ew tie eee ty ety eo ace aa rea 21 Estimated length composition of bigeye tuna caught by American purse seiners in the eastern tropical Atlantic |... «avers, caps oa + sm 6 bod 3 ec pimMe Colones oe oe siete cii..aeaee ismeener 22 iv Length Composition of Yellowfin, Skipjack, and Bigeye Tunas Caught in the Eastern Tropical Atlantic by American Purse Seiners GARY T. SAKAGAWA,' ATILIO L. COAN,' and EUGENE P. HOLZAPFEL? ABSTRACT Sampling and analytical procedures that are used to estimate the size composition of Atlantic tunas caught by American purse seiners in the eastern tropical Atlantic are described. The procedures are based on a stratified, two-stage subsampling model. Estimates indicated that about 0.2 to 1.4 mil- lion yellowfin tuna, Thunnus albacares, 1.2 to 12.8 million skipjack tuna, Katsuwonus pelamis, and 0.5 to 41.2 thousand bigeye tuna, T. obesus were caught annually by the fleet in 1968-74. The dominant age group in most years was l1-yr olds for yellowfin and skipjack tuna and 2-yr olds for bigeye tuna. INTRODUCTION United States participation in the eastern tropical At- lantic tuna fishery off west Africa began in the 1950’s. It was not until 1967, however, that significant numbers of U.S. purse seiners entered the fishery (Sakagawa and Lenarz 1972; Sakagawa 1974). Since then as many as 36 American® seiners have participated annually in the fishery. The American tuna fleet that fishes in the eastern At- lantic consists primarily of purse seiners of 80 to 1,800 metric tons carrying capacity of fish. Home bases for U.S. vessels are in California and Puerto Rico; the eastern Atlantic is only one of several areas where the vessels fish in a year. Each seiner has upwards of 20 fish- holding wells that freeze and store an average of about 60 metric tons of tuna per well. The fishing season in the eastern tropical Atlantic, while year round for most fleets, begins about July and usually ends in November-December for most American vessels. The American vessels generally fish in close proximity to each other, although they are operated by independent captains. Their catch consists of yellowfin, Thunnus albacares, and skipjack, Katsuwonus pelamis, tunas primarily and some bigeye tuna, T. obesus, and in- cidental catches of little tunny, Euthynnus alletteratus, frigate and bullet mackerels, Auxis spp., and rainbow runner, Elagatis bipinnulata. In 1967-69, more than half the catch was yellowfin tuna; since 1969, skipjack tuna ‘Southwest Fisheries Center, National Marine Fisheries Service, NOAA, La Jolla, CA 92038. "Southwest Fisheries Center, National Marine Fisheries Service, NOAA, La Jolla, CA 92038; present address: National Marine Fisheries Service, NOAA, P.O. Box 2223, Main Station, Mayaguez, Puerto Rico 00708. °The fishing operations of Canadian, Dutch (based in Willemstad, Netherlands Antilles), Panamanian, and U.S. boats fishing in the eastern tropical Atlantic are monitored as a unit by the Inter-American Tropical Tuna Commission. ‘“‘American”’ in this report refers to this fleet, which in 1968-73 consisted of at least 83% U.S. seiners. has been the dominant species in the catch (Sakagawa and Lenarz 1972). Virtually all the U.S. catch is returned to the United States aboard the seiners or aboard trans- shipment vessels for processing, canning, and mar- keting. Transshipments were made in 1970-74. Monitoring of the American catch to assess stock abundance was initiated by the National Marine Fisheries Service (NMFS), NOAA, in 1968 and con- tinued annually since then. Catch, effort, and length- frequency samples are collected by NMFS represen- tatives and under contract by the Inter-American Tropical Tuna Commission (IATTC) representatives. Summaries of catch and effort data were reported in Sakagawa and Lenarz (1972) and Sakagawa (1974). This report presents a description of procedures used to es- timate the length composition of tunas in the American catch and the estimated length composition of tunas caught in 1968-74. SAMPLING PROCEDURES Tuna catches were sampled for length-frequencies aboard the seiners during unloadings at canneries in California and Puerto Rico in 1968-74, and during un- loadings at freezer storage facilities and onto transship- ment vessels in west Africa in 1971-73. Samples were also obtained from transshipment vessels that unloaded at canneries in California and Puerto Rico. Sampling in west Africa was particularly critical in 1971 because in that year, and in 1970 to a lesser degree, large yellowfin and bigeye tunas with presumably high mercury content were selectively shipped to Europe, where a higher mercury content was acceptable, rather than to the United States. Samples taken only in Califor- nia and Puerto Rico in those years were therefore biased. Sampling in west Africa also presented the oppor- tunity of sampling the transshipped catch before it was mixed in the holds of the transshipment vessels. Up- wards of 700 metric tons of fish have been transported in a hold of a transshipment vessel. The transshipped catches of individual seiners are kept separate, but an entire seiner’s catch, which is usually caught in several areas and over several months, is generally loaded into a single hold. Length-Frequency Samples The sampling procedures were virtually the same as those recommended by Hennemuth (1957) for the eastern tropical Pacific fishery, i.e., a stratified, by area and month, two-stage subsampling procedure (Cochran 1963) was used. The boundaries of the areas (Fig. 1) were drawn according to the distribution and concentration of fishing effort of the American fleet. The first stage of the sampling was to choose the well (or hold if a transshipment vessel‘) to sample. The se- cond stage was to draw from the selected well a random sample of each species (yellowfin, skipjack, and bigeye tunas). Ancillary information, such as well number and catcher vessel name, was recorded for each sample. The date, location (NMFS area — Fig. 1), and tonnage of the catch sampled were obtained from logbooks after the samples were drawn. Before 1972, samples were obtained on an opportunis- tic basis and the sample size varied (10 to 300 fish). Since 1971, a goal of 6 skipjack samples and 12 yellowfin samples of 50 fish each from each NMFS area and each fishing month was established in an attempt to ensure a more complete area-month coverage. The larger number of samples for yellowfin tuna was required because of the greater variability in sizes of this species (Hennemuth 1957). This goal, however, was not attained in any of the years. Total Catch by NMFS Area-Month Total catch, by species and month, of tunas caught in the Atlantic by American vessels is tabulated annually by the IATTC from landing receipts. Logbook infor- mation on estimated catch by species, 1° area, date, and well number in which the catch is stored for each net set is also collected by the IATTC from virtually the entire American fleet. This logbook information was used to identify those seine sets that contributed to the catch in wells that were sampled and also to prorate the total catch by species of the entire fleet into catch by NMFS area-month strata. ANALYTICAL PROCEDURES Different areas apparently contain different sizes of fish, at least for yellowfin tuna in the eastern tropical At- lantic (International Commission for the Conservation of Atlantic Tunas 1974a), and the stratified sampling procedure, by month and area, was designed to account partly for this difference. Sizes of fish in the total ‘It is not uncommon to find several species stored in a well. The fish are partially thawed in the wells before unloading at the canneries or onto a transshipment vessel. Measurements were made on partially thawed fish. a ~ § on 2 o Figure 1.—Map of the eastern tropical Atlantic where American seiners fish for tropical tunas (shaded area). Numbered statistical areas used in this report are shown. American catch were estimated from the stratified length-frequency samples and catch. When a sample is drawn from a well, complete infor- mation on date, location, and tonnage of catch is not al- ways available; complete information is obtained later from the ship’s logbook. Fish that may have been caught in different strata were, consequently, sometimes drawn in a single sample. These samples were not used in our analysis unless 75% or more of the tonnage in the well was caught in a single NMFS area-month stratum. Because of this rule, virtually all samples from trans- shipment vessels were not used in this study. Analyses currently underway which contain a special stratum for transshipment samples may lead to new procedures for utilizing much of the rejected samples. Weighting Factor The sample size was fixed and not proportional to the numbers of fish in the well. Each sample was therefore weighted by a factor (number of fish) based on the species tonnage and average weight of fish in the well or, when this was unavailable, on the species tonnage and average weight of fish in seine sets that contributed to the catch in the sampled well. Substituting Samples Samples were unavailable for all area-month strata in which the fleet caught fish. For strata without samples, it was necessary to make assumptions about the catch and substitute samples from adjacent strata, within year to estimate the sizes of fish caught by the fleet. Sub- stitution was on the basis of the following rules: 1) use same month and adjacent areas; 2) use same area and adjacent months; 3) use adjacent months and adjacent areas. These rules are ordered according to priority and are based on the assumption that differences in sizes of fish from widely separated areas or months are greater than differences in sizes of fish from adjacent areas or months. In Tables 1 and 2 the area-month strata with sub- stituted samples are shown for yellowfin and skipjack tunas caught in 1968-74. About 20 to 60% of the strata in which yellowfin tuna were caught and about 10 to 60% of the strata in which skipjack tuna were caught had no samples and substitutes were necessary (Table 3). In terms of tonnage, substitutions were required for 2 to 29% of the total yellowfin tuna catch and 1 to 17% of the total skipjack tuna catch. The poorest sampling coverage of yellowfin and skip- jack tunas was in 1970. In that year, representative sampling was difficult because large yellowfin and bigeye tunas were transshipped in west Africa to foreign ports and not sampled. The best sampling coverage, in terms of tonnage, was in 1969 for yellowfin and 1971 for skip- jack tuna. Estimating Length Composition of Catch Length-frequency of fish in the total catch by species was computed by summing estimates for each area- month stratum. The following procedures were used for the stratum estimates: 1. The weight (w in kilograms) of each fish was es- timated from length (/ in centimeters) based on the appropriate length-weight equation (Lenarz 1974) shown below. The average weight (w ,) of fish in the sample, i = 1, 2,..., k, was then estimated. Table 1.—Catch (metric tons) and number of length-frequency samples of yellowfin tuna by NMFS area-month strata. Samples substituted in strata without samples are identified in parentheses. Month - year Catch (tons) Samples January 1974 February 1974 March 1974 May 1970 1972 June 1970 1972 1974 July 1969 1970 1971 1972 1973 1974 August 1968 1969 1970 1971 1972 1973 1974 September 1968 1969 1970 1971 1972 1973 1974 October 1968 1969 1970 1971 1972 1973 1974 November 1969 1970 1971 1972 1973 1974 December 1974 Catch Samples (tons ) Catch Samples (tons) (July-51) (July=51) (May- 51) (June-51) (July-51) SW Han PMM LP (Oct-53 a=! () —wH bg a fl (Nov.-51 Table 2.—Catch (metric tons) and number of length-frequency samples of skipjack tuna by NMFS area-month strata. Samples substituted in strata without samples are identified in parentheses. Month - year Catch Samples Catch Samples Catch Samples (tons) (tons) (tons) (July 51) January 1974 February 1974 March 1974 May 1970 1972 June 1970 1972 1974 July 15969 1970 1971 1972 1973 1974 August 1968 1969 1970 1971 1972 1973 1974 September 1968 1969 1970 197] 1972 1973 1974 October 1968 1969 1970 1971 1972 1973 1974 November 1968 1969 1970 1971 1972 1973 1974 December 1974 (July-51) (July-51) (June-51) 2 5 (July-51) (June-51) (June-51) (July-51) 3 (July-51) ] (July-51) 2 (Sept-51) (Sept-51) 19 7 28 10 1 (Oct-51) (Sept-51) 9 2 13 6 (Oct>52) (Nov-51) (Oct-53) (Sept-51) (Sept-52) ] 5 (Oct-53) 6 7 (Oct-52) ] ] (Oct-53) ] ] 5 (Nov.-53) (Oct>52) 2 ] (Dec-52) (Nov.-51) yellowfin tuna according to the length-frequency distribution of the W =a(2:18) <10'458) 22 ith sample. skipjack tuna 4. A weighted average weight (w) of fish in all the bi af rn (S,GL 2410 se db samples of a stratum was estimated with M; as the 1eeye une weighting factor, 2 = 2(M_w,)/=M. : Ww =10225 XG 10 see) et 5. The number of fish (N) in the total catch (C) of a stratum was estimated with N = C/w. 2. Average weight was used to convert the well tonnage 6. The length-frequency distributions of all M,’s of a . ul bee foe a Maal eS) ETE Sr stratum were pooled and the pooled frequency dis- of fish (M; = 5 /0; ). tribution was used to estimate the length com- 3. M_ is distributed proportionately by 2-cm intervals, position of N. Table 3.— Sampling coverage of NMFS area-month strata in which yellowfin and skipjack tunas were caught by American tuna seiners in 1968-74. Species-year| Total Sampled (number ) Yellowfin 1968 1969 1970 197] 1972 1973 1974 Skipjack 1968 1969 1970 1971 1972 1973 1974 ] ESTIMATES OF LENGTH COMPOSITION OF CATCHES Yellowfin Tuna The estimated length compositions of yellowfin tuna in the 1968-74 catches by month strata, all areas com- bined, are shown in Appendix Tables 1 to 7. Area dif- ferences are presumed to be not as significant as monthly differences within a year. As many as four modal groups are found in the length- frequency distributions, but only two or three are promi- nent (Fig. 2). The prominent modes correspond to the apparent entering year class (approximately 33 to 47 cm long), 1-yr-old (48 to 85 cm long), and 2-yr-old (86 to 123 cm long) fish. The modal size of the apparent entering year class is peculiar in that it differs from the modal size of the 1-yr-old fish by about 18 cm. According to the growth curve for Atlantic yellowfin tuna of Le Guen and Sakagawa (1973), the difference should be about 57 cm if the two groups are 1 yr apart. Some possible causes for this difference are: 1) there is extreme sampling bias of the entering year class, and perhaps even of 1-yr-old fish in the catch, owing to differential availability or vul- nerability; 2) the entering year class in fact represents slower growing or later hatching fish of the same year Total Sampled Total (tons)]| Tons Percent | (number) Catch of 1,000 tons 5,830 19,760 9,810 3,830 12,100 3,300 5,620 19,410 6,920 3,750 11,640 25910 5,160 3,180 4,890 11,790 16,830 12,200 22,290 19,970 3,160 4,730 9,840 16,780 11,900 21,910 19,440 Number/ 4870 Only strata in which a catch was made are included. class as the 1-yr-old fish, i.e., from multiple spawnings (Richards 1969); or 3) that the growth curve of Le Guen and Sakagawa (1973) is incorrect. Both 1) and 2) are probably the major causes for the difference. Hen- nemuth (1961) similarly identified length modes that were less than a year apart in age and presumably from identical year classes or subpopulations of yellowfin tuna from the eastern tropical Pacific. In 1968-74, about 0.2 to 1.1 million yellowfin tuna were caught annually by the American fleet in the eastern tropical Atlantic. The age-frequency distributions of the catches (Table 4), based on analysis of modal progres- sion and the growth curve of Le Guen and Sakagawa (1973), indicate that the dominant age group was 1-yr- old fish in 1968 and 1970-74, and 2-yr-old fish in 1969. The catch of 1969 is unusual compared to that of the other years. Besides the dominance of 2-yr olds in the catch of that year, the 1969 catch (in weight) of yellow- fin tuna was the highest recorded for the American fleet and virtually all (98%) was taken in NMFS area 51. About 90% of the catch, furthermore, was from pure yel- lowfin schools, the remainder from mixed yellowfin-skip- jack schools. In the other years, a smaller percentage (61 to 75%) of yellowfin tuna was caught in area 51 and only about 60% of the catch was from pure yellowfin schools. Yellowfin tuna in mixed yellowfin-skipjack schools are generally smaller than in pure yellowfin schools PERCENT FREQUENCY 8) 40 50 60 70 80 90 wo 110 20 130 40 0 60 FORK LENGTH (cm) 30-40 50 60 70 80 390 100 No 20 (130 140 150 60 170 30 «40 50 60 70 80 90 100110 20 130 140 150 60 170 FORK LENGTH (cm) Figure 2.—Estimated length composition of yellowfin tuna caught by American seiners in the eastern tropical Atlantic, 1968-74. (Solid line — stratified procedure; dashed line — unstratified procedure.) (Calkins 1965). The predominance of large yellowfin tuna (> 100 cm) in the 1969 catch could have been caused therefore by the high percentage of pure schools fished in that year. Skipjack Tuna The catch of skipjack tuna by the American fleet markedly increased from 3,180 metric tons in 1968 to 22,290 metric tons in 1973, then decreased to 19,970 met- ric tons in 1974 (Table 3). This represents for skipjack tuna an estimated 1.2 million in 1968, 12.8 million in 1973, and 10.6 million in 1974. The estimated length composition of the 1968-74 catches by month strata, all areas combined, are shown in Appendix Tables 8 to 16. Two apparent age groups, probably 1-yr-old (31 to 55 cm long) and 2-yr-old (56 to 67 cm long) fish, con- tributed to the catch (Fig. 3). The dominant group was 1- yr-old fish in all years except 1969 (Table 5). The dominant modal length in the skipjack catch decreased from about 50 to 55 cm in 1968-70 to about 45 cm in 1971-74 (Fig. 3). This decrease, while relatively small, occurred with the discovery by the American fleet in 1971 that skipjack fishing is good off Angola (NMFS area 52) during the fall months. Before 1971 most of the Table 4.—Estimated age composition of yellowfin tuna caught by the American purse seine fleet in the eastern tropical Atlantic. Approximate Estimated catch (numbers) by year length (cm)| 969 1969 1970 1971 1972 1973 1974 35-51 29,900 | 169,100 52-91 230,300 | 116,900 92-125 54,200 | 339,600 126-149 16,400 | 142,900 150-169 38,600 | 41,100 170+ 19,400 3,200 358,900 | 643,700}1,110,800 | 460,100 | 1,414,600] 245,900 1974 PERCENT FREQUENCY 1973 ~ 40 50 60 70 30 40 50 60 70 FORK LENGTH (cm) Figure 3.—Estimated length composition of skipjack tuna caught by American seiners in the eastern tropical Atlantic, 1968-74. (Solid line — stratified procedure; dashed line — unstratified procedure.) 907,500 | 186,600 63,000 77,700 25,700 7,000 368,300} 25,200 46,700 763,600} 122,000 | 157,800 81,100 218,500} 82,700 99,500 16,300 46,600} 15,300 99,800 15,300 700 13,400 7,000 2,300 417,200 American catch was made in the Gulf of Guinea and only about 3 to 21% of the skipjack tuna was caught in area 52. Since the discovery in 1971, as much as 98% of the an- nual American catch of skipjack has been taken from area 52. Bigeye Tuna Bigeye tuna are not often available to the surface fisheries (purse seine and pole-and-line) of the eastern tropical Atlantic. This species is sometimes confused with yellowfin tuna and catches may have been included with yellowfin tuna catches, but the amount is probably small. The American fleet reported bigeye tuna catches only in 1968 and 1971-74. A few length-frequency samples were collected in those years (Table 6). Because the samples were few, estimates of the length com- position of the catch were based on all samples com- bined without stratification, i.e., all catches and samples pooled and one estimate calculated for each year (Ap- pendix Table 17): About four major modal groups (39 to 51 cm, 52 to 73 cm, 74 to 105 cm, and 106 to 131 cm) can be identified in the length-frequency distributions (Fig. 4). These groups apparently represent age groups of 1 to 4 yr, based on Table 5.—Estimated age composition of skipjack tuna caught by the American purse seine fleet in the eastern tropical Atlantic. Approximate Estimated catch (numbers) by year lenge taken) bi nm ™~ ooooococooomoo°0o°co°0°0°co ~ > nm N 0 -0 0 -0 -0 0 -0 -0 -0 0 -0 -0 -0 -0 -0 0 -0 0 -0 -0 -0 -0 0 -0 0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 10 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 —n S00 HM SHH M0 BH HW HH MH MH BW RPWYPENNNFNNHOH HOODOO HHHWODDOHNNOHHNON—NO—ON—NOFS eo0ccooc~o—CoCCOCOCOCOOOOCOCOCOCOCOCCCOCCOCCCCCCCCeoo°ooooooOoOoOoOoOoOOo oooocoo°co°c;cooco°co 133236 14 Appendix Table 4.- Estimated length composition of yellowfin tuna caught by American purse seiners Nn the eastern tropical Atlantic in 1971. Number of fish by month idea Maeda cal ed 0 0 0 763 0 0 11530 17676 11668 13291 8928 5066 4541 9779 NOOCOOCCOCOCOCOCOCO0CCOCO°0C° ~ ooo loko lokokohokolosoloowogoe ce) 90 37 w COooCCCOCOCOCOOCOCOOOCCOCOCCCCCCCoCO0C0OMW 7 0 0 0 0 0 0 0 0 0 0) 0 0 0 0 0 0 0 0 0 0 0) 0 0 0 0 121377, | 175931 15 Appendix Table 5.- Estimated length composition of yellowfin tuna caught by American purse seiners' in the eastern tropical Atlantic in 1972. Midpoint Number of fish by month length (cm) 83 28 -0 0 -0 0 -0 -0 <0 -0 -0 0 0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 0 -0 -0 ooooocooocoococoococeoceo0co0c00c0coceoccoceoCcCeeococeCceCceocoCceCecCCcCcCeeCeeCeCeceCce°e°o°coeooc°o°coe°ococoocococo°Ccoceo COTDVVWVVWOWOOWFfUWOWD oooo°oo—o0coeo0cco 561304 16 Appendix Table 6.— Estimated length composition of yellowfin tuna caught by American purse seiners jn the eastern tropical Atlantic in 1973. Midpoint Number of fish by month Length (cm) . s . Nov. =) ive} ao oowoooo°oc°oo —_ ine) eS fos) COwodOnDODO0O000 & of co o1@ oO woo oo Lolo lo holo koko Noho Noho o koko oho oho hoo o goo pogao soi) :~ DS) wo ooo hook holo koko oko kono nono ono ogos ho goko goer i—) o0000000000000°0 foololololono holo o lok og ook oeioyo) oo0o0o00o0c00o0000 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 0 -0 -0 a0 -0 0 -0 -0 all -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 0 -0 -0 -0 int Appendix Table 7.—Estimated length composition of yellowfin tuna caught by American purse seiners in the eastern tropical Atlantic in 1974. Midpoint Number of fish by month Length (en) | oan. | Feo [mor | oun. [ our [ aus. [ sent. | oct. [ tov. | ec. | 0 0 0 0 87 33 0 5.0 540 0 37.0 0 0 0 0 87 0 0 0 0 39.0 0 0 0 0 745 132 2609 0 0 41.0 142 139 1893 174 0 43.0 189 186 2524 793 0 45.0 241 237 3218 928 0 47.0 73 72 978 1089 0 49.0 147 144 1956 875 0 51.0 121 118 1609 875 0 53.0 525 516 7003 349 0 55.0 503 495 6719 1525 0 57.0 603 592 8044 2854 0 59.0 366 360 4890 3734 0 61.0 262 258 3502 2298 0 63.0 168 165 2240 770 0 65.0 73 72 978 652 0 67.0 73 72 978 910 0 69.0 0 0 0 257 0 71.0 143 140 1906 201 0 73.0 191 187 2544 772 0 75.0 143 140 1906 1311 0 77.0 96 94 1276 1218 0 79.0 11 110 1488 2088 0 81.0 118 116 1572 1141 0 83.0 276 272 3689 688 0 85.0 138 136 1845 0 0 87.0 290 285 3872 457 0 89.0 274 269 3659 1028 0 91.0 65 64 874 1336 0 93.0 18 18 243 457 0 95.0 16 16 213 201 0 97.0 32 31 425 288 0 99.0 34 34 455 370 235 101.0 138 136 1847 1208 0 103.0 65 64 874 1226 118 105.0 0 0 0 1378 118 107.0 236 232 3155 989 109.0 280 276 3744 2122 111.0 358 352 4785 3833 113.0 298 293 3979 2811 115.0 147 144 1956 4671 117.0 95 93 1262 4299 119.0 139 136 1852 4800 121.0 63 7 62 844 3131 123.0 63 7 62 844 3232 125.0 26 3 26 347 990 127.0 50 6 49 661 87 129.0 16 is 6 16 213 594 131.0 18 2 7 18 243 663 133.0 0 0 0 0 0 707 0 135.0 2 0 ] 2 30 292 355 137.0 5 ] 2 4 61 436 0 139.0 23 3 8 22 303 349 0 141.0 2 0 1 2 30 262 0 143.0 25 3 9 25 334 518 0 145.0 20 2 8 20 273 493 0 0 147.0 18 2 7 18 243 349 0 0 149.0 5 ] 2 & 61 117 0 0 151.0 14 2 5 13 182 466 0 0 153.0 1 ] 4 11 152 292 0 0 155.0 5 ] 2 7 61 0 0 0 157.0 11 ] é 11 152 174 0 0 0 159.0 0 0 0 0 0 0 0 0 0 161.0 9 ] 3 9 121 0 0 0 0 163.0 5 ] 2 4 61 87 0 0 0 165.0 2 0 1 2 30 0 0 0 0 167.0 5 ] 2 4 61 0 0 0 0 169.0 5 1 2 4 61 0 0 0 0 171.0 0 0 0 0 0 0 0 0 0 173.0 2 0 ] 2 30 0 0 0 0 Total 7592 7458 =| 101351 71134 93195 18 Appendix Table 8.— Estimated length composition of skipjack Appendix Table 9.— Estimated length composition of skipjack tuna caught by American Purse seiners in the eastern tuna caught by American purse seiners in the eastern tropical Atlantic in 1968. tropical Atlantic in 1969. Midpoint Number of fish by month Length (em) | Aug. | sent. | oct. | Nov. | Midpoint Number of fish by month length -0 2409 .0 4739 .0 0 0 0 .0 18759 0 .0 0 9257 2409 0 51955 2013 .0 32798 70624 12046 .0 57873 5965 -0 | 131436 139866 68875 .0 96038 15956 .0 | 123675 91380 25709 ‘0 65096 32961 .0 28540 39476 22903 ‘0 73737 45359 .0 58833 21281 11452 ‘0 147494 48242 .0 45815 19055 27127 0 157306 63066 .0 26035 28488 24718 ‘0 91651 59256 .0 25036 36659 11254 ‘0 54032 46465 .0 1752 34206 19900 0 33216 34248 .0 0 9901 2211 0 7631 10974 .0 1752 1076 0 0 1431 2259 501269 231013 475672 860958 366764 Appendix Table 10.— Estimated length composition of skipjack tuna caught by American purse seiners in_ the eastern tropical Atlantic in 1970. Midpoint Number of fish by month aie eee | ‘Cem ee ee 24835 0 4943 0 0 0 2446 12334 24835 32939 11349 19219 39089 149012 16469 11242 91520 | 135299 311362 0 2476 96812 | 206739 301012 41173 32304 74613 91742 442347 | 151716 75504 44155 67015 381942 | 170979 87829 25827 35296 250967 | 218438 | 128026 14935 14286 41588 | 121571 | 123720 18418 7986 56027 87236 | 115101 5666 8398 17866 46369 13692 13004 2141 3983 1844 6212 0 3789 0 -0 -0 0 .0 -0 0 0 -0 .0 0 0 -0 -0 -0 -0 a) 421287 | 637975 858387 | 636061 | 205079 19 Aopendix Table 11.— Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1971. Teas Number of fish by month 0 es ee 0 0 778 0 3879 0 -0 0 1054 13973 10622 0 .0 1715 1969 79921 87724 22140 -0 5358 2552 423894 572735 27721 0 37829 11730 601535 591718 99537 0 80052 62618 921515 389419 135261 0 47581 94475 612368 533072 126521 0 18539 91279 361004 220877 120755 0 14683 97721 384174 313773 57679 -0 4394 68150 155941 355220 54889 0 6109 25970 70307 236933 32933 0 0 10751 21632 90572 10978 -0 2250 19227 20129 -0 1715 1969 4787 -0 0 0 3722 -0 1715 864 0 3674000 219690 474130 Appendix Table 12.— Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1972. Number of fish by month md ee 0 0 0 2275 0 4106 42896 11985 0 8569 4646 44684 | 305230 100456 64367 13833 56322 | 497974 244828 206845 27127 64237 | 335621 391793 233145 50895 89352 | 231361 277366 109356 38305 278838 | 367061 300561 128683 86480 268123 | 279298 301074 179767 57565 126408 | 173796 111142 165454 61671 19085 59862 42428 113891 23297 22120 8954 30863 83770 4106 13263 2383 7122 27694 14373 2275 9277 4748 15051 8484 19586 0 3372 2323 26671 711 2984 0 9360 0 0 -0 -0 -0 -0 -0 -0 -0 a) -0 -0 -0 -0 -0 -0 -0 -0 397211 | 1085495 | 2284513 | 1812381 | 1342948 | 286946 20 Appendix Table 13.— Estimated length composition of skipjack tuna caught by American purse seiners’ in the eastern tropical Atlantic in 1973. Midpoint length (cm) Number of fish by month 3696 3340 5663 62958 26879 3935 163760 | 147907 21511 476786 | 688219 185781 848494 | 1392101 317625 935517 | 2028754 478645 716497 | 1518342 630823 383647 | 706955 388533 98730 | 133770 177279 12382 11543 45677 6024 0 2819 8747 9252 0 68 1998 CODCOD OOO Oo OOoOoSO 127154 | 3722576 2258291 Appendix Table 14.— Estimated length composition of skipjack tuna caught by American purse seiners in the eastern tropical Atlantic in 1974. Midpoint Number of fish by month Length (cm) 317157 2002 458035 22462 425648 57965 38702 | 767286 | 415456 207593 61805 | 121033} 680598 | 631623 236729 53455 | 102638} 455170 | 208315 260544 163939 | 102108) 507089 | 300723 243426 61760 74915| 262163 | 128828 | 115659 | 123428 110056 | 105090) 172428 27220 72673 55381 11743 30830} 437149 26957 31378 2472 18203} 502969 47175 27108 8892 12519} 318003 6739 22506 9018 10518} 118255 6739 12866 0 5786 44346 0 908 2384 14782 0 9018 795 0 0 8564 0 0 0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 0 -0 -0 -0 -0 0 0 584059 | 645623) 5617170 |1733236 | 519095 21 Appendix Table 15.— Estimated length composition of bigeye tuna caught by American purse seiners in the eastern tropical Atlantic. Midpoint Number of fish by year Length (on 0 70 S>PPpPw Ow—wo o mM > Ns 0 0 0 0 0 0 WOWOWWOWO DDD WDONNNNNAANHDADMNMNMNNHS ONMNW MON OTWHONONWHONONWHONONw—wo -0 0 0 0 -0 -0 -0 -0 -0 0 0 -0 0 0 -0 -0 -0 -0 -0 -0 =Q -0 -0 -0 0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 -0 22 tr U.S. GOVERNMENT PRINTING OFFICE: 1976—697-845/117 REGION Ame Bookbinding Co., Inc. 100 Cambridge St. Charlestown, MA 02129 ae CONF Bees . * a yh Coe Ser aay ee Pene Ur kag 3 POT ec ay as +e See meee =. aay 4 Ae ‘ i : f 4 : . : Serene rants h : : Si Inte ele) A