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Home , Anchovy, Mackerel

POTENTIAL CATCH OF THE PRESENT SAN PEDRO WETFISH FLEET BY JOHN 1. BAXTER’ Marine Rerourcer Branch, California Department of and Game Sacra mento, Californio and C. E. BLUNT, JR? Marine Resources Region, California Department of Fish and Game long Beach, California INTRODUCTION terviews, and landing figures show that the boats op- erate for an average of 15 or 16 days per month. This We were asked to comment on the potential catch figure takes into consideration time lost to inclement of the San Pedro wetfish fleet as based on past per- weather, repairs, and rest periods. It does not include formances and reflected in our catch and effort data. time lost because of strikes and other economic prob- After evaluation of the large amount of data avail- lems. At a fleet capacity of 2,450 tons and 15 operating able we tabulated catch and effort from each log on a days per month, the monthly capacity of the fleet is weekly basis by general areas. We utilized fish- 36,750 tons. The annual capacity is 441,000 tons. ing log data from 1968 and most of 1969, at least as much of it as time allowed. The work we did made it ASSIGNMENT OF EFFORT quite clear that a great deal more effort will have to be directed toward the collection and processing of We are quite aware of the problems inherent in as- log interview data. signing effort in a multi-species , and plan to By law, vessels fishing the northern , En- spend a great deal more time on this problem. graulis mordax, for reduction are required to submit For the purpose of developing estimates of the po- a record of fishing operations when landing their tential catch of the wetfish fleet we computed catch catch. Thus, the anchovy log program reflects effort per hour of scouting time for the San Pedro fleet dur- from successful trips very well but reporting unsuc- ing 1968 and most of 1969. The basic catch and effort cessful trips, which at times may be significant, is in- data were obtained by our log and log-interview pro- complete. Our log program will also require a great grams conducted in conjunction with routine age and deal of additional effort to ensure that unsuccessful length sampling at the waterfront. Skippers fishing trips for (Pacific mackerel, Swmber japoni- €or are required to make out a fishing log cus and jack mackerel, symmetricus), Pa- when landing their catch. Fishing and scouting infor- cific , Sarda chiliensis, bluefin , mation pertaining to jack mackerel, Pacific mackerel, thynnus, and other species are properly reported. , bonito, and bluefin tuna are obtained each Therefore, the catch per unit effort figures and other day through interviews with vessel skippers as they data presented must be considered preliminary and unload their catch or when they dock at San Pedro subject to possible change as a result of more complete after an unsuccessful trip. Due to lack of manpower analysis. we have not been able to follow completely the daily activity of each vessel in the fleet; however, we be- PRESENT FLEET lieve that in most months we have obtained logs for about 90 percent of the fleet activity, especially dur- In 1947 the San Pedro wetfish fleet was made up of ing 1968. about 250 vessels. This fleet fished primarily for the Log catch and hours of scouting were summarized Pacific , Sardinops caeruleus. Shortly there- on a weekly basis for each month by general fishing after, the sardine fishery collapsed and by 1954 the areas. Fishing effort was assigned as either being (i) fleet had shrunk to 137 boats. Ten years later only 54 jack and Pacific mackerel, (ii) anchovy, (iii) bonito, boats remained in the fleet. At present the fleet in- and (iv) tuna (bluefin and , Thunnus ala- cludes but 29 active vessels. These range in registered lunga). We established 12 general areas off southern length from 39 to 80 feet and can carry from about California and 1 for northern Baja California. Fish- 25 to 150 tons of fish. An additional six vessels nor- ing effort was assigned on the basis of the species com- mally fish for tuna in tropical waters but occasionally position of the catch in a general area during the fish for bonito and tuna (primarily bluefin tuna) weekly summary. For example, if only mackerel were locally and might enter the wetfish fishery under cer- taken in an area, all effort in that general area was tain conditions. These vessels are 80 to 90 feet long classified as mackerel effort. If only bonito were taken, and have a capacity of about 120 to 180 tons. the effort was classified as bonito effort. Occasionally The daily capacity of the wetfish fleet as based on both bonito and mackerel were taken in a general loads of anchovy is 2,450 tons. Our log book data, in- area, and when one or the other did not dominate by Present address : National Marine Service, Washing- at least 80 percent of the weekly catch, the effort was ton, D.C. not utilized in the catch-effort summation. During OPresent address: Department of Fish and Game, Eureka, California. 1968 very little effort had to be eliminated for this 34 CALIFORNIA COOPERATIVE OCEANIC FISHERIES INVESTIGATIONS reason simply because the tuna, mackerel, and bonito COP1 area (Blunt, 1969). The proportion of jack fishing areas were distinct during most of the weekly mackerel off California has not been estimated. We periods. Anchovy fishing areas are also distinct in that have no estimate of biomass; however, it has generally they are well outside the 50 fathom isobath been generally acknowledged as very large. The squid as opposed to mackerel fishing which is well within catch off California has ranged between 4,000 and 12,- it. During 1969 the fisheries were not as distinct with 000 tons per year since 1961. bonito being caught more often in mackerel areas, The amounts of bonito and bluefin tuna that might and bluefin tuna being taken closer to land masses in be harvested off California under the right conditions usual mackerel catch areas. In the case of tuna we are indicated by California Department of Fish and were able to classify many trips as tuna trips by de Game catch records. These data show that as much as tailed information on the logs which the skippers sup- 9,000 tons of bonito have been caught in California plied. waters. During the mid-1930’s the California catch of bluefin tuna was about 9,000 tons per year. In recent RESOURCE BASE years the bluefin tuna catch reached a high of 8,500 The species normally considered as the resource base tons in 1962. for the San Pedro wetfish fleet are Pacific mackerel, POTENTIAL CATCH sardines, jack mackerel, anchovies, squid (Loligo OPU- lescens) , bonito and bluefin tuna. The populations of For this symposium we are interested in the poten- sardines and Pacific mackerel are at extremely low tial catch of our present fleet, fishing in their normal levels. There is a moratorium on sardine fishing (15 areas and with current gear and operating methods. percent tolerance allowed with mixed catches), and We are confronted with the imponderable question Pacific mackerel are caught in only small quantities in “What species do you want to base the estimates on, conjunction with fishing for the other species. There- and how much effort do you want to spend on each?” fore, these species are not regarded as part of the re- We know full well that economics and institutional source base at this time. problems have direct consequences upon what the Biomass estimates for northern anchovies and jack fishermen catch. In 1969 the anchovy catch increased mackerel have been published based on and larva to about 50,000 tons as compared to 15,500 tons for surveys by the U.S. Bureau of Commercial Fisheries 1968, generally because more effort was put into the (now National Marine Fisheries Service). These show anchovy fishery. a biomass of 4 to 6 million tons of anchovies (50 per- Based on the catch rates of the fleet during 1968 cent off California), (Messersmith et al, 1969), and and most of 1969 (Table l), and assuming complete 1.4 to 2.4 million tons of jack mackerel in the Cal- effort toward anchovy fishing except during the

TABLE 1 Southern California Wettish Fleet Preliminary Log Catch, Effort, and Catch per Effort Data

Log Catch Catch per Effort Log Scouting Hours (Short Tons) (Tons/Hour) Total Year/ Bluefin Scouting Bluefin Bluefin Bonito Anchovy Tuna Hours Mackerel Bonito Anchovy Tuna Mackerel Bonito Anchovy Tuna -I---- 1068 Jan.--- 733 2,229 1,454 __ 1.98 Feb.--- 1,057 1,861 1,051 203 .99 Mar.--- 388 625 282 .74 Apr.--- 788 987 2,062 2.62 May-.- 1.201 1.346 3,057 2.55 __ 952 3,194 -- I _- 3.35 I 862 1,321 1,304 -- -_ 2.84 __ 1.516 2.599 997 1.135 __ 3.94 Sept.--- 577 724 2.529 992 1.123 __ 1.72 Oct.- ___ 1 778 128:- 1 .261 1,167 2,254 __ 2,309 2.90 Nov.--- 1.034 370.5 -- 1,405 3.619 -_ 5,005 3.50 1.131 3.558 363 3,051 4.48 3.70 12.8

1,585 1,613 438 1.358 2.25 .66 6.7 825 2.088 __ 322 2.76 _- 4.7 945 2,973 _- 1,767 3.7 _- 13.0 1,240 1,560 -- 7.855 2.40 -- 13.3 1.173 1,515 __ 3,753 1.8 __ 11.4 1.384 2,029 1.5 _- _- 2,069 3,041 2.5 .5 _- __ ._ 1,979 _- _- 8.6 __ __ 1: 1 14,808 -- -- 15.7 _- __ -- 10,011 -- -- 14.4 __ ------_------REPORTS VOLUME XV, 1 JULY 1969 TO 30 JUNE 1970 35

TABLE 2 HYPOTHETICAL EFFORT ALLOCATION Based on 1968 and 1969 Log Data (Assumes availability and catchability equivalent to 1968 and 1969, also assumes good economic conditions and demand for fish) = JAN. FEB. MAR. APR. 1 MAY JUN. JUL. 1 AUG. SEP. OCT. NOV. DEC. --- ~~~ I ___- I- I- Percent Allocation Mackerel_____ - - - - - 50 50 50 50 30 30 35 45 45 Bonita______------20 20 20 20 3 I :: I 30 10 10 10 10 Anohovy______30 30 30 30 20 35 45 45 Tuna------_- -- -- I _- __ 1 40 40 40 20 __ _- Hours of Scouting Mackerel ______1,015 943 1,015 1,015 1,160 1,114 835 812 979 914 Bonito--- ______406 377 406 406 464 1.114 278 232 218 203 Anchovy ______609 565 609 609 696 __ 557 812 979 914 Tuna-----.------_- -- __ __ _- 1,484 1,114 464 -- _- , 1

Fleet gross 2,450 tom/day 36,750 tona/month 441,OOO tom/year Ave. 15 days fishing/month Ave. 5 hours swuting/day 29 purse seiners summer closure, the present fleet could conceivably catch approximately 210,000 tons of anchovies per year. If they fished for mackerel and tuna during the May 15 through September 14 period (cloed to anchovy fishing for reduction) they could potentially catch 12,000 tons of mackerel and 700 tons of tuna. In conjunction with mackerel scouting they could bring in 2,300 tons of bonito. As based on 1968 data this would assume complete effort on mackerel in June and 60 percent effort on mackerel and bonito and 40 percent effort on tuna during July, August, and the first half of September. These estimates, of course, as- sume equivalent availability as occurred in 1968 and 1969. A more realistic situation would be to assume the effort. allocation itemized in Table 2. This resembles the fleet’s effort allocation during 1968 and 1969, and assumes good demand for the northern anchovy. It also assumes equivalent abundance and availability as in the base period. The potential catch under this situation would be 32,000 tons of mackerel, 4,000 tons October November December of bonito, 75,000 tons of anchovies, and 1,200 tons of tuna. The tuna catch could very well reach 2,000 and Anchovy------306 229 218 3,000 tons, or higher, in some years since the abun- Mackerel------217 262 336 dance, availability, and catchability of this trans- oceanic migrant may change significantly from year to year. (Table 2.) These estimate.; of potential catch are somewhat hypothetical since their attainment depends on a num- ber of assumptions. These are: 1. Good economic demand. 2. AI1 vessels fish approximately 15 days each month, and average 5 hours of scouting per day. 3. Allocation of effort is as indicated in Table 2. 4. Availability and catchability of the exploited is equivalent to the base years. 5. Catch per unit of scouting effort observed during months of base years will be maintained with higher fishing intensity.