surveyed. Only catch temperature data for albacore catches within 

 the survey area are given. 



Each sportfishing boat operating for hire from California is 

 required by CF & G to maintain a daily fishing log of the catch by 

 species , location of catch (block area number) , and number of fisher- 

 men on board. Catch records do not indicate species targeted by 

 anglers, or the fishing technique used. A species-preference order is 

 known to exist with the coastal recreational fishermen; in the north, 

 salmon is a highly desirable species, and off southern California, 

 albacore, yellowtail, Pacific barracuda, and white seabass are high 

 on the preference list. In addition, species-specific lures and/or live 

 bait are fished near the surface, in mid water, or close to the bottom. 

 The lack of detailed catch data prevents the allotment of "effort" to 

 the catch of any one species. However, the catch and numbers of 

 anglers participating may be related, particularly for those species 

 that are of high priority to the marine angler. Reports of better-than- 

 average fishing, whether true or not, usually result in increased fish- 

 ing effort; therefore the catch may or may not be a reflection of 

 increased availability in localized fishing areas. The relationship of 

 catch to number of anglers for data collected in 1 972 through 1 974 is 

 discussed in Part II. 



Basic environmental data for the analysis involved monthly tem- 

 perature measurements derived from isotherm charts drawn from air- 

 borne infrared temperature data for the period August 1963 through 

 July 1968. The surveyed region included 40 block areas off central 

 California having a reported catch of salmon (2,460 temperature 

 observations), and 130 block areas off southern California in which 

 catches of either yellowtail, Pacific bonito, Pacific barracuda, alba- 

 core, or white seabass were reported (7,800 temperature observa- 

 tions). Temperature data developed from continuous analog 

 measurements in degrees Fahrenheit are given as Celsius and Fahren- 

 heit. 



Monthly catch locations for the 5-yr period were obtained from the 

 CF&G sportfishing boat log records for catches of 347,867 salmon, 

 161,375 yellowtail, 4,047,292 Pacific bonito, 2,439,512 Pacific bar- 

 racuda, 129,535 albacore, and 42,328 white seabass. 



to 62.0°F). Waters in this area are coolest during January through 

 May or June, with the lowest temperature recorded in April. Temper- 

 atures increase slightly from June through September when the peak 

 average temperature occurs, then drop again after September 



Major peaks in the salmon catch for the fishing area off San Fran- 

 cisco occur in March and July (Fig. 2). To the north of Bodega Bay, 

 the peak catch is in July, and south of Monterey two catch peaks 

 occur, one in May and one in July. Chinook are the salmon most often 

 caught, because as the Sacramento River system holds spawning Chi- 

 nook salmon during most of the year and these pass through the major 

 ocean fishing areas off central California. However, the fail ran of 

 chinook salmon is the largest, and fish congregate off the San Fran- 

 cisco Bay area for the spawning migration. 



Figure 2.— Distribution of salmon catch off northern California (Monterey 

 Bay to Bodega Bay) by month, August 1963- July 1968, for total catch, catch 

 temperature, and sea surface temperature range and means, and the standard 

 deviation about the means. 



Results 



Data on catch by species for each month from August 1963 

 through July 1968, and monthly temperature data for the 5-yr survey 

 period, were processed by the Northwest Fisheries Center, Seattle, 

 Wash. A computerized data analysis determined the following: the 



mean catch temperature, X^ 



_E(/lxl+/2x2- 



■). 



the standard 



Z(fl+fl+...) 



deviation about the catch temperature mean (a ); and the array of 

 catch by temperature as well as the number of fish in each sample for 

 each species by total area, and by individual block area, month, and 

 year Temperature ranges, means, and standard deviations were cal- 

 culated for the same geographical areas and time groups as the spe- 

 cies data. 



Data are presented for salmon off central California, and for yel- 

 lowtail, Pacific bonito, Pacific barracuda, white seabass, and alba- 

 core off southern California (Fig. 2-19c). These illustrate catch, 

 catch temperature, and temperature range on a regional geographical 

 basis (central California and southern California). 



Central California (Monterey Bay, San Francisco, and 

 Bodega Bay) 



The ocean temperature of the major fishing area for salmon (from 

 Monterey Bay to off Bodega Bay) ranged from 9.4° to 16. 7°C (49.0° 



The catch temperature mean for all salmon catches off San Fran- 

 cisco for the 5-yr period is greater than the sea surface temperature 

 mean, except for November (Fig. 2). The monthly catch temperature 

 mean is equal to or greater than the temperature mean from January 

 through October, which indicates that more salmon were caught 

 when the temperature was greater than its monthly mean. The catch 

 temperature mean was below the temperature mean during Novem- 

 ber; however, this was a period of near zero salmon catch. Figure 3 

 indicates those blocks having a recorded catch of 1 ,000 salmon or 

 more during the survey period, the month having the greatest catch, 

 the temperature at which most salmon were caught, the mean catch 

 temperature, and the number of salmon in the sample. 



The major fishing area off San Francisco early in the year is in the 

 vicinity of Point Reyes, south of Drakes Bay and Duxbury Reef 

 (March/blocks 447, 448, and 449). The major fishing area moves to 

 near the Farrallone Islands and the San Francisco Light Buoy during 

 the summer (June- July /blocks 456, 457, 458). In late summer the 

 fishing area moves closer to the Golden Gate (August-September/ 

 blocks 446, 455). Mean catch temperature ranged from 11.2° to 

 13.6°C (52.2°-56.5°F). 



The review of the three leading block areas (448, 446, 457) in 

 catch is given in Figure 4a, b, c, showing for each block area the dis- 

 tribution of catch by temperature and by month for catch, tempera- 

 ture at which most salmon were taken, the monthly mean catch 

 temperature, and standard deviation of the mean catch temperature. 



