Abstract

Preliminary growth and mortality parameters for the spiny lobster Panulirus argus were estimated from length frequency data collected from the St. Croix commercial fisheries from 1995 through 1999 using the FISAT software package. The corresponding values of L¥ for female spiny lobsters using ELEFAN I ranged from 170 to 177 mm CL, and K values were 0.20 to 0.23. For males the L¥ values ranged from 185 to 197 mm CL, and K values ranged from 0.23 to 0.28. The length-converted catch curve and Beverton and Holt Z estimates ranged from 1.24 to 1.91 for males and 0.8 to 1.58 for females. The Z estimated from Jones length cohort analysis ranged from 0.83 to 1.15 for males and 0.65 to 0.83 for females. The exploitation ratios from length catch curve ranged from 0.73 to 0.82 for males and 0.58 to 0.76 for females. Meanwhile, exploitation rates from Jones length cohort analysis ranged from 0.59 to 0.70 for males and 0.47 to 0.64 for females. Nevertheless, average exploitation ratios ITom the two different methods were well above the optimum exploitation rate (E=0.5) suggesting that the St. Croix spiny lobster is overfished. The Bevertonrelative yield per recroit model analysis for 1999 for males implies that with values of E=0.66 and Lc=95.4 mm the current lobster fishery is harvesting approximately 98% of the potential yield. Likewise, the analysis for females shows that with a value of E=0.58 and Lc=89.36 mm the fishery is harvesting 95% of the potential yield in females. According to these results, it is very important for all fishery agencies in the US Caribbean to reevaluate the status and conditions of the spiny lobster stocks and the definitions of overfishing for this economically important resource.

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