Longline Fishing 



Five baskets of longline were fished with 

 each set of gill nets by attaching them to an end 

 of the set. The longline was similar to that 

 used previously to fish albacore in this area 

 (Mann 1955). The basic unit or basket co.isist- 

 ed of 210 fathoms of mainline to which floats 

 were attached at either end. Three-fathom 

 droppers with 1 1/2-fathom leaders were sus- 

 pended from the mainline at 15 -fathom inter- 

 vals so that there were 13 hooks to a basket. 

 This basic gear was modified to fish at varying 

 depths by changing the depth of the floatline 

 and placing an extra buoy at the center of the 

 basket (omitting the hook at that position). The 

 five baskets were arranged in the following 

 order, starting at the attached end: Two had 

 3 buoys (one in the center) and no floatlines; 

 two had 2 buoys and no floatlines; and the fifth 

 had 2 buoys and 2 -fathom floatlines. A sound- 

 ing tube (Graham 1957) was placed on each 

 basket of gear; and these showed that during 

 the cruise the minimum fishing depth was about 

 25 feet and the maximum about 430 feet. No 

 albacore were taken on this gear (tables 6 and 

 7). 



A single albacore (68.6 cm. in fork length) 

 was captured on a special set of longline which 

 replaced a scheduled gill-net station cancelled 

 because of a winch breakdown. Five baskets, 

 each equipped with 3 buoys (one in the center) 

 and no floatlines, were fished. This special 

 set was made immediately following a catch of 

 fish on trolling lines and extended from 1345 

 through 1800 hours (fig. 2). The hooks were 

 baited with snaall herring (<6 inches), in con- 

 trast to the five baskets attached to gill nets on 

 which large herring (>6 inches) were used. 



STOMACH ANALYSES 



One hundred and ninety-five albacore 

 stomachs were examined in the field and 43 

 stomachs, believed to contain food, were pre- 

 served for laboratory analysis. In the field 

 study, food items were divided into the follow- 

 ing major groups: Squid, saury, other fish, 

 shrimp-like plankton, and copepod and 

 amphipod-like plankton. Food items of the first 

 three groups were rated as to size by consider- 

 ing total lengths less than 5 inches as small, 5 

 through 10 inches as medium, and greater than 

 10 inches as large. The displacement volume 

 (>5 nnl. ) of the contents of each stomach was 

 determined and any unidentifiable remains 



noted. The data obtained with both types of 

 gear, troll and gill net, are presented in table 

 10. 



HOLDING EXPERIMENTS 



The rectangular port brine tank, 8 1/2 feet 

 deep and 6 1/2 feet wide fore and aft, of the 

 John R. Manning was used to hold troll-caught 

 albacore which were landed alive and in good 

 condition. Water entering the tank flowed 

 diagonally across the upper portion of the tank 

 and then returned along its sides and bottom. 

 Water was removed from the bottom; diagonally 

 across from the inflow. The volunne of flow 

 was such that the contents of the 2, 150-gallon 

 tank were replaced approximately every 35 

 minutes. Fourteen albacore, ranging fronn 54 

 cm. to 68 cm. in fork length, were held in the 

 tank for periods varying from a few minutes 

 to 14 hours (table 11). 



NIGHT-LIGHT 

 OBSERVATIONS 



Observations of organisms under lights 

 were nnade from the Snnith (table 12), the 

 Manning (table 13), and two charter vessels 

 (table 14) while they were drifting at night. The 

 Smith made her observations under deck lights, 

 which remained on all night, by estimating 

 every 2 hours the number and size of sauries 

 present. The Manning turned on the deck lights 

 for 1 hour during darkness and estimated the 

 number, and usually the size, of sauries and 

 squids which were attracted. The charter vessel 

 Flicker made observations between 2130 and 

 2200 hours each night using a single sealed- 

 beam light. Twenty or fewer sauries, when 

 seen at one instant during the period of obser- 

 vation, were classed as few, 2 1 to 50 as 

 moderate, and 51 or more as abundant. The 

 Rowland R. Sr. made her observations at 2200 

 and the amount of bait or forage and the amount 

 of lunninescence were recorded in relative 

 terms. 



SIGHTINGS OF FISH, BIRDS, 

 AQUATIC MAMMALS 



The wheel watches of the Snnith and 

 Manning maintained logs of fish, birds, and 

 aquatic mamnnals sighted during the daylight 

 hours. These observations are tabulated in 

 tables 15 and 16. The charter vessels also 

 maintained a rough log of such sightings which 

 are tabulated in table 17. 



19 



