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Spatial and temporal scales of the US Pacific sardine fishery

Word document summarizing scales of the biology, stakeholders, economics and governance of the sardine fishery

Sardines and sea lions

Biological scales of variability



      • Population distributed from 23ºN - 57ºN and throughout Gulf of California when abundances are high. Population contracts to area south of Pt Conception when abundances are low. Three stocks: Northern (northern Baja to Alaska), Southern (off Baja), and Gulf of California.

      • Found in upper 50 m of water column

      • When abundance is high, probably migrate along coast from Baja to British Columbia, depending on stock biomass and oceanographic conditions (Hart 1973).

      • Recent spawning concentrated offshore and north of Pt Conception (Lo et al. 1996)

      • Historical spawning between Pt Conception and San Diego, out to ~100 mi offshore, max ~250 mi offshore (Hart 1973)


      • Populations vary over periods of ~60 years, declines lasting ~36 yrs, recoveries lasting ~30 yrs (Baumgartner et al. 1992)

      • Spawning year round, length of spawning period extends with warmer temperatures (Butler 1987, Ahlstrom 1960), peak between April - August (Allen et al. 1990)

      • Lifespan ~12-13 years

California sea lions


      • Population distributed from 19ºN - 50ºN and throughout Gulf of California.

      • Found in coastal waters (continental shelf and nearshore)

      • Dive to depths of 274 m.

      • Breed in southern part of range from Gulf of California north to San Miguel Island, CA.

      • Seasonal migrations over large portion of total range


      • Breed from May to July, peak in early July.

      • Lifespan ~17 yrs (Mate 1979)

Economic scales of variability



      • California (Monterey, Ventura / Port Hueneme, and San Pedro / Terminal Island), northern Baja (Ensenada), Pacific Northwest fisheries (OR, WA, BC)

      • Fishing activity concentrated relatively close to ports, receiving stations and processing plants - Within a few miles of port and within Monterey bay; along Ventura coast and offshore around Channel Islands; north and south of LA along coast, offshore banks and islands, such as Santa Catalina

      • Sales to Japanese long-line fishery for bait and to Australia to feed farmed tuna, plus smaller proportion sold for human consumption in Japan and locally

      • Processors and buyers concentrated in LA, Santa Barbara-Ventura, and Monterey, but located as far north as Watsonville and as far south as San Diego

      • 95% of catch from state waters, 5% EEZ


      • Collapses and expansions of fisheries on same time scale as sardines (<~60 yrs)

      • Processing time: ideally from harvest to frozen in <10 hrs

      • Transit time: ranges from <6 - 14 hrs for southern fishing grounds

      • Investments in vessels: age 11-53 yrs in Monterey; replacement cost $726,000 - $751,000; age 8-64 yrs in Ventura; replacement cost $714,000 - $1 million; age 11-65 yrs in San Pedro; replacement cost ~$1 million

      • Investments in operating expenses (fuel, maintenance, mooring, insurance)

      • Investments in purse seine nets, onboard refrigeration and other gear

      • Investments in spotting planes or lease of their time

      • Investments in processing plants, e.g. blast freezer systems

      • Investments in harbors, pumping stations, trucking and other infrastructure associated with receiving fish

      • City leases for fish receiving facilities on Monterey wharf - 5 year

      • Harvest concentrated in particular seasons (varying across the region)

      • Multigenerational family ties to fishing reported by ~2/3 of fishermen

      • Fluctuations in domestic and especially global demand

      • Fishermen's ability to shift their harvest among different wetfish species buffers variability in their abundance and price

      • Many fishermen harvest 1-2 other species (non coastal pelagic species such as salmon, herring or tuna) during other seasons to round out their year and diversify

      • Blast frozen and individual quick frozen fish can be frozen and stored to buffer against supply and demand fluctuations

Scales of management


      • Temperature at Scripps Pier used to modify target harvest level (via parameter FRACTION, which is a function of temperature, limited to the range from 5-15%)

      • EFH defined as “all marine and estuarine waters from the shoreline along the coasts of California, Oregon, and Washington offshore to the limits of the EEZ and above the thermocline where sea surface temperatures range between 10ºC to 26ºC” between the US-Mexico maritime boundary to the south and the position of the 10ºC isotherm to the north.

      • Limited entry fishery south of 39ºN (~Point Arena, CA) (recreational fishing, bait fishing exempt from limited entry requirements)

      • Open access fishery north of 39ºN (~Point Arena, CA)

      • US harvest levels set based on proportion of stock biomass in US waters (no cooperative agreement with Mexico or Canada)

      • Fishery divided into northern (39ºN, south to Point Piedras Blancas (35º40'N)) and southern segments (Point Piedras Blancas south to US-Mexican border), which get 33% and 66% of the total allocation respectively.

      • Existing and proposed MPAs


      • 3 year running average of SST used to modify target harvest level (via parameter FRACTION, which is a function of temperature, limited to the range from 5-15%)

      • Annual SAFE report and annual stock assessment

      • Permit renewal every 2 years

      • Annual permit fee

      • Maximum harvest level (MAXCAT) set to reduce year to year variation in catch levels, spread catch from strong year classes over more fishing seasons, avoid overharvest due to errors in biomass estimation, and to avoid overcapitalization during short periods of high biomass and harvest.

      • Target harvest levels and harvest guidelines (including incidental catch and directed fishery allowances) for individual fisheries published annually

      • Directed fishery is closed for the year if and when the harvest guideline for the directed fishery is reached, though incidental catch may continue.

      • 9 months after fishery opens, any uncaught portion of harvest guideline is allocated evenly (50-50) between northern and southern segments of the fishery

by Carrie Kappel last modified 31-05-2006 11:04

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