Resumen de The Black Murex Snail, Hexaplex Nigritus (Mollusca, Muricidae), in the Gulf of California, Mexico: II. Growth, Longevity, and Morphological Variations with Implications for Management of a Rapidly Declining Fishery
Richard Cudney-Bueno, K. Rowell
We assessed longevity, seasonal growth variation, age of reproductive maturity, and geographic variations in morphology of the black murex snail, Hexaplex nigritus (= Muricanthus nigritus) (Philippi, 1845), a heavily harvested species of the Gulf of California, Mexico. Results from mark-recapture,[delta]18O in shell carbonate, and 5 yrs of field observations, indicate that H. nigritus reach reproductive maturity between 2-3 yrs of age and live to be at least 8 yrs. Maximum growth occurs in the first year and slows down markedly in subsequent years. Seasonally, growth is accelerated during the summer and fall and largely stunted during winter, particularly January-March. Regional variations in morphology exist and have affected fishing practices, resulting in an artificial selection of stocks. We discuss our findings in the context of comparison of this species with other muricid snails and of the management implications for the black murex fishery.
