Table 1. — U.S. catch of lobsters by the inshore 

 pot fishery and offshore trawl fishery 



Year 



Pot 

 fishery 



Trawl 

 fishery 



Total 



Percentage 



of catch 

 by trawls 





- - - - -Metric tons 





Percent 



1943 



7,420 



30 



7,450 



0.4 



1944 



8,095 



37 



8,132 



0.5 



1945 



10,275 



34 



10,309 



0.3 



1946 



10,840 



35 



10,875 



0.3 



1947 



10,802 



51 



10,853 



0.5 



1948 



9,417 



59 



9,476 



0.6 



1949 



11,102 



124 



11,226 



1.1 



1950 



10,394 



129 



10,523 



1.2 



1951 



11,680 



89 



11,769 



0.8 



1952 



11,195 



159 



11,354 



1.4 



1953 



12,479 



275 



12,754 



2.2 



1954 



12,078 



386 



12,464 



3.1 



1955 



12,649 



482 



13,131 



3.7 



1956 



11,515 



510 



12,025 



4.2 



1957 



13,316 



357 



13,673 



2.6 



1958 



11,858 



484 



12,342 



3.9 



1959 



12,589 



592 



13,181 



4.5 



1960 



13,311 



810 



14,121 



5.7 



1961 



11,621 



1,056 



12,677 



8.3 



1962 



12,124 



1,236 



13,360 



9.2 



1963 



12,369 



1,366 



13,735 



9.9 



1964 



12,177 



1,855 



14,032 



13.2 



1965 



11,221 



2,481 



13,702 



18.1 



1966 



11,612 



1,774 



13,386 



13.3 



1967 



10,083 



1,949 



12,032 



16.2 



1968* 



12,300 



2,500 



14,800 



16.9 



^Preliminary. 



New Jersey. None of the Maine catch includes 

 offshore lobsters. 



The fishery operates at the edge of the 

 Continental Shelf, 100 to 300 km. from shore, 

 mainly in depths between 200 and 500 m. The 

 vessels, which are usually about 30 m. long, 

 operate on a year-round basis. The average 

 fishing trip lasts 10 days; the lobsters are 

 held alive in tanks until the vessel returns to 

 port. Catches during a trip may range from 

 1 to 9 metric tons, but the daily average is 

 about one -half a metric ton. Lobsters weighing 

 less than 2.25 kg. are termed selects and 

 command a premium price; larger lobsters 

 are called jumbos and sell for 50^ to $1.00 

 less per kilogram. The average annual price 

 to the fisherman is about $1.75 per kilogram, 

 for selects and $1.25 for the jumbos, but the 

 price of selects has been as high as $2.50 per 

 kilogram in late winter and early spring. 



The gear used in this offshore fishery is 

 the standard bottom trawl described by Bruce 

 (1967). If the bottom is rough, rollers are 

 added to the foot rope of the nets to help pre- 

 vent snagging. The boats fish around the clock, 

 and tows last 3 to 4 hours. 



Skud (1966) reported on preliminary sam- 

 pling of the offshore fishery but did not discuss 

 the differences among individual fishing 

 grounds. The objectives of the present paper 

 are to present the results of research cruises 

 and sampling of the commercial catch, and 

 to compare size composition, sex ratio, and 

 size at maturity of the lobsters caught in off- 

 shore fishing areas. 



SAMPLING 



Most of the samples of lobsters were taken 

 from catches at submarine canyons along the 

 edge of the Continental Shelf (fig. 1). As the 

 sampling stations had marked differences, we 

 discuss each of the canyon areas separately. 



Samples from the commercial catch were 

 taken throughout the year. At least 100 lob- 

 sters, representing all size categories, were 

 measured (carapace length) and sexed from 

 each of the landings sampled. In addition, data 

 on the vessel, gear, date sailed, date landed, 

 days fished, fishing days lost, area and depth 

 of catch, and total catch were obtained from 

 interviews with the vessel captains. 



During research cruises aboard the Alba- 

 tross IV and the Delaware , more detailed 

 data on tows were obtained, including the time 

 and distance as well as the range in depth of 

 each tow. Hydrographic data were collected 

 after each tow. Sampling during the research 

 cruises was concentrated in particular fishing 

 areas to determine seasonal changes in size 

 composition of sex ratio. Since these same 

 areas were also regularly fished by the com- 

 mercial fleet, we could compare the catches 

 of commercial and research vessels. The sex, 

 carapace length, and weight of each lobster 

 were recorded. The number of females with 

 external eggs (berried) was also noted. A 

 summary of the research cruises is presented 

 in table 2. 



The research cruises also provided infor- 

 mation on sublegal or prerecruit lobsters 

 which was not available from commercial 

 landings because of minimum-size restrictions 

 (7.8-8.1 cm. carapace length in various States). 

 Though the fishery operates in international 

 waters, which have no restrictions on lobster 

 fishing, State laws apply to the landings; con- 

 sequently the offshore fishery is subject to 

 the same size regulations that control the in- 

 shore fishery. All of the New England States 

 also prohibit the landing of berried lobsters. 



COMPOSITION OF CATCHES FROM 

 OFFSHORE CANYONS 



The five canyon areas discussed in this 

 paper were selected as sampling sites because 

 of their commercial importance or their geo- 

 graphic separation, to provide a composite of 



