Big Sur Hook and Line Fishing Survey

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Graphs of annual average fish lengths These graphs reveal trends in fish length over the years since 1991. In December 2000, three species showed the type of decline predicted if there were overharvesting: Gopher Rockfish (Sebastes carnatus), Black and Yellow Rockfish (Sebastes chrysomelas) and Grass Rockfish (S. rastrelliger). These species have been targeted by the live fish market and bring high prices. One other targeted species, Cabezon (Scorpaenichthys marmoratus), did not show a decline in average length. In 2001, these species' declines seemed to halt or even rebound slightly. Perhaps the new, highly restrictive regulations played a role in the recovery, although bad weather and other factors may have made a difference as well. In 2000 and 2001 two other species seemed to be on a declining trend, Olive Rockfish (Sebastes serranoides) and Copper Rockfish (Sebastes caurinus). However, relatively few of these species were measured (see data table) so the trend may not be meaningful.

Graph of annual average index weight This graph shows how "fat" the fish are in any given year since 1994. The data indicate that 1994 and 1997 were "lean" years for most of the species shown, while 1995, 1998, 1999, 2000 and 2001 were relatively "fat" years. The two species of bottom-dwelling gopher rockfish ("Gopher" and "Black and Yellow"; Sebastes carnatus and S. chrysomelas) do not show the trend, perhaps reflecting a different feeding strategy than the more streamlined open water species ("Vermilion", "Olive", and "Blue"; S. miniatus, S. serranoides, and S. mystinus).

Project summary The Big Sur hook and line fishing survey is a cooperative project involving a group of commercial fishers and the Big Creek Reserve staff. The project began in 1989, with quantitative data collection beginning in 1991. The relationship was essential for establishment of the Big Creek Marine Ecological Reserve in 1994, and has been the subject of sociological research by Carolyn Pomeroy of UC Santa Cruz. The Big Creek Reserve Manager has been responsible for managing the project and analyzing the data for presentation at an annual meeting with the fishers.

Each year the fishers launch their skiffs from the Big Creek beach between September and March, and travel outside the reserve to fish for commercial rockfish and other species. The data are recorded by the fishers themselves, based on a random sample of 10 taken from their daily catch, and entered with other information into a database by University researchers. Each day the fishers attempt to catch at least 5 fish from the Santa Lucia kelp bed. In addition, they record the first five fish, or a random sample of 5 fish, from the catch at their preferred fishing spots. Between 70 and 120 sorties ("boat launches") per year add up to a sample of about 700 to 1000 fish measurements each year. All fishing takes place outside the Big Creek Marine Ecological Reserve.

   

 Landing in Big Creek cove. The cove is somewhat protected from the surf by the cove rock and reef, making it a desirable launch point during the winter months.

 Measuring fish and recording data by the reserve parking area at the end of the day. The fishers put in very long days; after fishing all day they must drive their fish to market.

Fish lengths are measured on the boat. Upon returning to shore, the fishers weigh and measure a random sample of fish to obtain length-weight ratios for analysis of fish condition. The Annual average length shows if there are trends in the sizes of fish caught; the prediction is that if there is overharvesting the average size will decrease. The Annual average index weight is an attempt to measure the condition of the fish populations, to see if we can monitor year-to-year changes.

Annual average index weight of fish taken from the Santa Lucia Kelp Bed, and for fish taken from other kelp beds. Each species is assigned an "index length" which is used to calculate the estimated index weight, using hand-drawn regression estimates for each species in each year. Year-to-year variation in index weight is an estimate of the condition of the fish, with the prediction that in warm-water, low nutrient years the fish will have a reduced index weight.

 

Annual average length of fish taken from the Santa Lucia kelp bed, and for fish taken from other kelp beds ourside the marine reserve. See table of means for numerical data. Contact John Smiley for more information.

 

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