Status and Trend in the Southern California Spiny Lobster Fishery and Population: 1980-2011.

Abstract

The California spiny lobster (Panulirus interruptus) fishery in southern California ranks amongst the State's most economically important fisheries. An analysis of commercial harvest data confirms that the fishery was landing near-record catches in the late-2000s through early-2010s. Advances in recreational fishing technology likely tempered commercial fishery landings per unit effort. The commercial catch per trap pulled declined 15%, on average, in years after the introduction of a new rigid-style hoop net in the recreational fishery. Fishery-independent data sourced from power plant marine life monitoring recorded increased California spiny lobster abundance after 1989 with evidence of increased larval settlement beginning circa 1989. This timing was consistent with previously reported oceanographic changes in the North Pacific. Power plant abundance indices derived for lobsters approximately one year before recruiting into the fishery, as well as young-of-the-year, significantly predicted the commercial landings at index-appropriate temporal lags, i.e. one year for next year's recruitment. Carapace lengths measured during power plant surveys in Santa Monica Bay, where commercial fishing was prohibited, significantly declined for the total sample and females only after the introduction of the new rigid hoop net. Male carapace lengths were not significantly different between the two periods. The power plant data confirms that, as of 2012, the fishery appears healthy but warns of the need to monitor sublegal individuals and their dependence on oceanographic conditions. These analyses also indicate the urgency of monitoring the recreational fishery harvest, especially the potential effects of the new rigid hoop net.