BIOWGICAL DATA ON BERRY ISLANDS (BAHAMAS) QUEEN CONCHS, STROMBUS GIGAS, WITH MARICULTURE AND FISHERIES MANAGEMENT IMPLICATIONS

Biological data designed to assess the mariculture potential of queen conchs, Stromb1ul gigM, and to aid in management of stocks in the Berry Islands, Bahamas, were collected from March 1980 to February 1983. Juveniles congregated in shallow areas adjacent to cays with strong currents. Growth of queen conchs differed among cays and seemed related to conch density. Average growth rates from several cays in the Berry Islands showed that growth was slower than that reported for queen conchs in other areal' in the Caribbean. Estimated survival ofjuvenile queen conchs (about 10 em) was 57-80% per month, or 2-9% annually. Yield per recruit from this population can be maximized by harvesting the animals at about 15 em, which is the size at onsetoflip formation but may be below the size at maturity. Presently, potential for increasing queen conch production through intensive and/or extensive mariculture seems low because of high hatchery costs, lack of dependable mass-rearing techniques. high predation on young released in nature. and slow growth of penned conchs. The queen conch, Strombus gigas, a giant marine snail which is a major food resource in the Carib­ bean, Bahamas, and some Central American na­ tions, has been exploited by subsistence and com­ mercial fishermen for centuries. During the last several decades, recreational conch fisheries have developed and expanded considerably, placing high fishing pressure on these stocks. Until recently there has been little scientific research directed at improv­ ing production from existing stocks. The present study was designed to obtain biological data to ful­ fill this need in the Berry Islands, Bahamas. Based on its high fecundity, feeding habits, limited migration habits, and high market demand, queen conch appears to be a desirable candidate for both intensive mariculture (enclosed) and extensive mari­ culture (released into nature to augment natural stocks) (Berg 1976; Brownell 1977; Brownell et al. 1976; Brownell and Stevely 1981). Success of either type of mariculture is dependent upon technical ability to mass-rear queen conch inexpensively from eggs on a dependable basis, and on knowledge of optimal natural habitats for raising juveniles to a