Associations between sea temperature, catch per unit of fishing effort, and yield in the Bermuda spiny lobster fishery, 1975-1989

Abstract

Results of graphical analyses of annual records of catch, effort and sea temperature indicate empirical quadratic associations between industry catch per unit of fishing effort (CPUE) in Bermudan spiny lobster (Panulirus argus and P. guttatus) fisheries and the annual average sea temperature at Hamilton Harbour, Bermuda. CPUE and yield of P. argus and of P. guttatus were each associated by quadratic expressions with the annual average sea temperature of the Bermuda Platform. Annual growth and survival of late juvenile P. argus and P. guttatus into the fishable stock at Bermuda is controlled in a quadratic fashion chiefly by sea temperature with a six-month lag. The optimum annual average sea temperature for the survival and growth of late benthic juvenile P. argus into the fishery stock was 23.6 ± 0.2ºC (mean ± s.e.), and the comparable optimum for P. guttatus juvenile recruitment was 24.1 ± 0.1ºC. The maximum equilibrium catch of P. guttatus lobsters on Bermuda Platform was estimated at approximately 33 000 lobsters from quadratic regression of yield on fishing effort.