August 1966 



COMMERCIAL FISHERIES REVIEW 



25 



best catches of big-eyed tuna in recent years 

 were made there. 



A total of 34 STD lowerings and 55 BT low- 

 erings were made to study the water struc- 

 ture in the vicinity of the cooperating Hawaii- 

 an long -liners (the Kaku, Pulpo, and Aukai) 

 and southward to the subsurface front area. 

 The STD lowerings made while traveling south 

 indicated that the subsurface front was lo- 

 cated approximately at latitude 12°30' N., 

 longitude 158°00' W. The results showed that 

 the long-liners were fishing about 180 miles 

 north of the subsurface front area where 

 transitional waters with surface salinities of 

 34.60-34.70 percent overlayed a tongue of 

 North Pacific Central Water located at depths 

 centered at about 130 meters (427 feet) with 

 salinities of 35.05-35.06 percent. 



A total of 5 long-line stations using 60 bas- 

 kets of 6 -hook gear were occupied along long- 

 itude 158° 00' W. while headed south to locate 

 the subsurface front; 5 stations were made in 

 the front area and 5 were made in the area 

 fished by the cooperating long-liners. A total 

 of 4 5 big -eyed tuna (28-205 poundsTTS 7 striped 

 marlin, 2 white marlin, 11 shortnosed spear- 

 fish, 31 dolphin, 74 great blue shark, 11 thresher 

 shark, 3 whitetip shark, 2 mako shark, 30 

 lancetfish, 9 sting ray, 6 wahoo, 5 skipjack 

 tuna (14-18 pounds), and 7 yellowfin tuna (87- 

 127 pounds) were caught. The results showed 

 that there were more apex predators caught 

 in the subsurface front area than were caught 

 in the area fished by the local long-liners. Of 

 significant abundance in the front area were 

 the dolphin and shark. The catch of big-eyed 

 tuna in the front area was only slightly better 

 than that made in the area of the long-liners. 



A total of 41 big-eyed tuna blood samples 

 was collected and preserved. 



Other activities of the cruise included: 

 standard weather observations; daily thermo- 

 graph records and barograph records were 

 kept; 5 skipjack blood samples were collected 

 and preserved; 3 sting ray were preserved 

 for identification; 1 yellowfin tuna and 1 big- 

 eyed tuna were chilled and 9 big-eyed and 3 

 yellowfin were frozen for physiological stud- 

 ies. 



A total of 18 surface plankton tows (30 min- 

 utes each) was taken each night; incidental 

 surface trolling was conducted when traveling 

 between fishing stations and en route to Hon- 

 olulu; weight, length, and sex of all tuna and 



the weight and sex of the marlin were re- 

 corded; and the stomachs of marlin and dol- 

 phin were exaxnined for juvenile tuna whenever 

 possible. 



Note: See Comroercial Fisheries Review , June 1966 pp. 9 and 10. 



Columbia River 



SHAD NETTING ACTIVITIES 

 DURING 1966 SEASON: 



With the Columbia River closed to gill- 

 netting of salmon to protect the summer Chi- 

 nook and sockeye runs, both the Oregon Fish 

 Commission and the Oregon State Police re- 

 ceived numerous calls in regard to netting 

 activities along the river, said that State's 

 Fisheries Director. Behind the inquiries was 

 the fact that the shad season was open for 

 commercial fishermen, he pointed out. 



Under regulations set cooperatively with 

 the Washington Department of Fisheries, the 

 shad season runs from noon May 26 to noon 

 June 25 in area 1-S (vicinity of St. Helens to 

 near Corbett) and from noon May 26 to noon 

 July 15 in area 2-S (near Corbett to the usual 

 commercial fishing deadline 5 miles below 

 Bonneville Dam). During these seasons, there 

 is a 30 -hour weekly closure each week from 

 noon Saturday to 6:00 p.m. Sunday. The Fish- 

 eries Director emphasized that because of 

 mesh size, strength, and design of the nets, 

 relatively few salmon and steelhead are taken 

 in the shad fishery. Those that are caught 

 must, by regulation, be immediately returned 

 to the river. The special shad season is set 

 to allow harvest of this abundant species 

 while at the same time protecting the salmon. 

 Studies conducted last year showed that simi- 

 lar regulations satisfactorily accomplished 

 that objective. Although some salmon were 

 taken in the shad nets, most were alive and 

 were returned to the river. 



Shad were introduced into the Columbia 

 River and also in the Sacramento River in 

 California during the late 1800's. They in- 

 creased rapidly and became established in 

 various other coastal streams. Columbia 

 River shad numbers have been high during 

 recent years, and in 1965 a record 617,000 

 passed over the fish ladder at Bonneville. 

 Many others spawned in the mainstem Colum- 

 bia below the dam, especially in the Washoug- 

 al Reef area. 



