RESEARCH IN 1966 



Pelagic investigations were nnade off Cali- 

 fornia fronn 21 January to 25 March. The 

 vessel Pribilof sailed from Seattle on 18 

 January and the Lynnann from San Francisco 

 on 21 January. 



Observation watches aboard the Pribilof 

 were nnaintained while the vessel cruised south 

 167 to 185 km. (90 to 100 miles) offshore from 

 Cape Flattery, Wash., to central California and 

 on the return trip when it traveled 9 to 111 km. 

 (5 to 60 miles) offshore. Dates, areas, dis- 

 tances traveled, and number of seals seen were 

 as follows: 



DISTRIBUTION OFF CALIFORNIA 



A survey of seal distribution off the central 

 and southern California coast was made along 

 transects run at 37-km. (20-mile) intervals 

 between latitudes 32° N. and 38° N. The 

 Pribilof began the survey on 30 January inlat. 

 32" N. Observations were made from dawn to 

 dark each day that sea conditions permitted. A 

 distance of 185 to 222 km. (100 to 120 miles) 

 was run on a transect during this period. The 

 vessel moved north at night to the next tran- 

 sect line. The Lynnann assisted with a few 

 transects but principally was used to collect 

 seals. 



Configuration of the ocean bottom in the 

 region surveyed is shown in figure 29 and the 

 distribution of fur seals expressed as seals 

 seen per hour in different months is shown in 

 figures 30-32. A comparison of figure 29 with 

 figures 30 to 32 shows that seal densities are 

 often greatest near seavalleys, seamounts, or 

 along the Continental Shelf, where there are 

 abrupt changes in depth and upwelling of 

 nutrient- rich bottom water creates a very 

 productive area. 



The amount of time vessels occupied a 

 square, and the number of seals seen, the 

 number collected, and the nunnber seen per 

 hour (density value) are shown by nnonths in 

 tables C-1 to C-3. The highest density (41.1) 

 in any square occupied for more than 0.5 hour 



was observed in March, southwest of Pt. 

 Buchon (V18-H24), where 111 seals were seen 

 in 2.7 hours. Values of over 10 seals per hour 

 usually denote above-average densities. 



In January, areas of seal abundance were 

 located 37 to 46 km. (20 to 25 miles) west of 

 San Miguel Island, near the Monterey Sea- 

 valley, and west of the Farallon Islands and 

 Cordell Bank. 



In February, seals were abundant 130 to 148 

 km. (70 to 80 miles) west of San Miguel Island, 

 56 km. (30 miles) west of Pt. Conception, off 

 Monterey Bay and Monterey Seavalley, 1 1 1 to 

 130 km. (60 to 70 miles) west of the Farallon 

 Islands, and off the western edge of Cordell 

 Bank. 



In March, seals were abundant southwest of 

 Pt. Conception, 93 to 1 1 1 km. (50 to 60 miles) 

 northwest of Pt. Arguello, and 74 km. (40 

 miles) west of Pt. Piedras Blancas. They were 

 less numerous near the Monterey Seavalley. 



Seals were scarce south of lat. 34° N. during 

 the 6 days spent in this area, although they 

 have been abundant there in other years. D. W. 

 Rice (whale marking cruises, unpublished field 

 notes for 1962, 1964, and 1965) found them in 

 abundance 74 to 93 km. (40 to 50 miles) west 

 of San Nicolas Island, and 19 to 56 km. (10 to 

 30 miles) northwest of Cortes Bank in January 

 1965. He observed seals in smaller numbers 

 near San Miguel, Santa Rosa, San Nicolas, and 

 San Clemente Islands, off Pt. Loma, and south 

 to lat. 30° N. V. B. Scheffer saw fur seals off 

 Pt. Loma, and near Santa Cruz and San Cle- 

 mente Islands in 1952 (Taylor, Fujinaga, and 

 Wilke, 1955). 



Seals are found regularly during the winter 

 and spring, January to June, between lat. 34° N. 

 and 38° N. Ln April, May, and June 1965 seal 

 concentrations were present west of Pt. Reyes, 

 on Cordell Bank, west of the Farallon Islands, 

 and near the Monterey Seavalley (Fiscus and 

 Kajinnura, 1967). Numbers are usually greatest 

 37 to 130 km. (20 to 70 miles) off central and 

 southern California. 



Surface water temperatures in the survey 

 area were 12° to 15oC. in January, 10° to 15° 

 C. in February, and 11° to 14° C. in March. 

 Usually the highest temperatures were found 

 offshore and the lowest temperatures nearer 

 shore. 



RELATIVE ABUNDANCE OF SEALS AND 

 SIZE OF GROUPS 



The number and relative abundance of seals 

 seen and collected off California in 1966 are 

 shown in tables C-4 and C-5. From 21 January 

 to 3 1 March an average of42.9 seals were seen 

 per boat-hunting day. In 1961 during the same 

 period off California, 37.2 seals were seen per 



54 



I 



