Abstract

Queen conch (Strombus gigas) are economically and culturally important throughout the greater Caribbean region. However, recent surveys have shown declines throughout their range. In The Bahamas, there exists one of the last viable conch fisheries, but overfishing and illegal juvenile harvest is observed throughout the family islands. In Eleuthera, many local residents rely on marine resources, particularly conch, for subsistence. Population declines may have devastating effects on an already impoverished part of the country. A marine protected area has been suggested for South Eleuthera, but without current information on conch populations and identification of essential habitat, ideal placement and effectiveness cannot be assessed. To determine the health of the local conch population, we performed surveys in two crucial habitats: shallow water habitat and deep water breeding grounds. Utilizing towed snorkel surveys, we obtained necessary baseline data in nearshore habitat with moderate fishing pressure; preliminary results show low numbers of conch, with a mean density of 18 conch/ha. The deep water surveys (performed on SCUBA) were compared to surveys from the 1990s, to determine if local waters are still used by conch for reproduction. Although mating and egg masses were identified in the deep water, the mean density of 11 adults/ha is significantly lower than previous population estimates, and below the threshold identified for a healthy breeding population. Coupled with midden surveys that show only 14% of locally harvested conch are adult, the data suggest a drastic decrease in the South Eleutheran conch population, a potential early sign of population collapse.

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