12 



COMMERCIAL FISHERIES REVIEW 



Vol. 28, No. 10 



which is better equipped to transport live fish. 

 The bigeye were taken by pole and line. Big- 

 eye tuna have oversized eyes and long, slen- 

 der pectoral fins sweeping back in a pro- 

 nounced curve almost to the tail. 



Fig, 2 - Ashore netted tuna being transferred to portable tank. 

 The fish will be kept in the portable tank ready for transporta- 

 tion to larger tanks where they will be kept and used in several 

 studies of tuna physiology and behavior. 



Bureau scientists believe the bigeye can in- 

 crease the information obtained from studies 

 of other tunas- -about vision, hearing, use of 

 olfaction in food search, and how they main- 

 tain swimming depth. Bigeye have swim blad- 

 der; yellowfinhave much smaller one; skipjack 

 none. 



Large and old bigeye tuna, caught at 400- 

 600 feet throughout the tropical Pacific, make 

 up about 20 percent of Japan's annual tuna 

 landings. In recent years, heavy catches 

 were made southeast of Hawaiian Islands, 

 Bigeye are a premium food fish. 



The most substantial U,S, catch of bigeye 

 is in Hawaii, where long-line fleet took 336 

 tons in 1965, These were older fish caught 

 deep. Bigeye command good prices. Small 

 quantities are caught by the California fleet. 



Gr*<rt Lokes Fishery Investigations 



LAKE ERIE YIELDS POOR HATCH OF 

 WALLEYES, YELLOW PERCH 



The 1966 hatch of yellow pike (walleyes) 

 and yellow perch in Lake Erie was the sec- 

 ond lowest average recorded in 10 years, 

 says BCF's regional office in Ann Arbor, 

 Mich. This preliminary evaluation is based 

 on relative distribution and abundance of 



young-of -the -year fish collected in the west- 

 ern basin. Trawling data through the end of 

 1966 may change estimate slightly--but out- 

 look is discouraging. The "northeaster" that 

 pounded lake shoreline in late April 1966 dur- 

 ing peak spawning period apparently had 

 tremendous adverse effect on walleyes and 

 yellow perch. 



Trawl samplings reveal fairly good hatch 

 of white bass and channel catfish. Onlysheeps- 

 head among commercial species are enjoying 

 an exceptionally good year. 



Forage fish --including alewives, gizzard 

 shad, spottails, and emerald shiners --are at 

 about same levels of abundance in recent 

 years. 



North Pacific Fisheries Explorations 

 and Gear Development 



SURVEYS HAKE POPULATION 



The BCF research vessel M/ V John N, 

 Cobb returned to Seattle in August after 4 

 weeks of exploratory fishing off the Pacific 

 Coast between southern Vancouver Island, 

 B.C., and northern Oregon. 



Its primary objective was to determine 

 distribution and availability of Pacific hake 

 ( Merluccius productus ). Secondary objectives: 

 (1) to assist commercial vessels in locating 

 hake schools, (2) obtain biological data on hake, 

 and (3) get additional data on availability of 

 hake to Cobb pelagic trawl. 



Echo-sounding transects were made to lo- 

 cate hake schools. When a school was located, 

 it was fished with the Cobb pelagic trawl to 

 determine the availability of hake, then sound- 

 ed out to determine the school's dimensions. 

 This information was passed on to commer- 

 cial boats. 



No large schools were found, but small ones 

 were located, fished, and sounded. Most 

 yielded less than 200 pounds of hake per-hour 

 haul, but two produced catches of 1,870 and 

 5,278 pounds an hour. Both schools were lo- 

 cated off Willapa Bay; the first in deep water 

 along the 73- to 100 -fathom depth contour cov- 

 ering an area of about 15 square miles; the 

 second was found in shallower water along the 

 37- to 38 -fathom contour and covered about 5 



