The Queen Conch (Strombus gigas) is a large marine snail that has historically been a primary food staple for the people of the Greater Caribbean and The Bahamas. Today, conch remain an important socioeconomic resource for commercial fishermen throughout the region.
An Over-Exploited Resource
As with many other fisheries in the world, queen conch fisheries have become threatened by over-exploitation. In the 1970’s Caribbean stocks began to show signs of serious decline. The conch fishery in the Florida Keys officially collapsed in 1975 due to over-fishing and commercial harvest was quickly banned. Later (1985) commercial and recreational fishing was banned in all Florida waters. Bermuda’s conch fishery also collapsed during the late 1970’s. Despite strict regulation, neither fishery has recovered. Other countries such as Jamaica and Cuba have been forced to use fishing moratoriums repeatedly over the last decades to prevent over-fished stocks from collapsing.
In 1992, concern for the future of the species lead the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to list queen conch in their Appendix II which includes species not necessarily threatened with extinction, but for which trade must be controlled to avoid utilization incompatible with their survival. Since 1995, CITES has been reviewing the biological and trade status of queen conch and has recommended that the importation of conch be prohibited from 8 countries. Queen conch continues to be a commercially viable fishery in a few Caribbean countries, including Jamaica and the Turks and Caicos Islands (British West Indies), which CITES considers to be well-managed, and Belize and the Bahamas where more management has been requested and the end of export suggested.
The queen conch (Strombus gigas) is particularly vulnerable to over-fishing for several reasons:
- Long-lived and late to reproductive maturity. Besides being one of the largest marine mollusks, the queen conch is also a long-lived species. Conch reach reproductive maturity when they reach 3-5 years in age. They also develop the flared lip of their shell during this life-cycle phase, but the presence of a flared lip does not necessarily mean that a conch has reached reproductive maturity. It is estimated that Queen conch may live up to 30 years in age.
- Mating behavior. Queen conch reproduce in large spawning aggregations during the summer months when fishing pressure is the greatest. An aggregation may consist of thousands of individuals in a small geographic area making it easier for fishermen to over-harvest a population.
- The Allee effect. Conch need relatively high population densities to reproduce and replenish a fished population. If numbers within a population decline greatly it is possible that mating will not occur at the frequency needed to sustain itself leading to population collapse (Stoner and Ray-Culp, 2000).
Signs of Decline in the Bahamas
Compared to other conch fisheries in the Caribbean, The Bahamas is fortunate to have comparably vast areas of suitable conch habitat and a relatively small human population size, which has allowed the harvest of conch to continually increase when it seemed all other nation’s stocks were in trouble. But today, the signs of stock decline in The Bahamas are undeniable. Evidence for the impact of fishing on conch populations was provided 15 years ago by Stoner & Ray (1996) who showed that densities of adults on the shallow bank in the Exuma Cays Land & Sea Park (a no-take marine reserve), were 31 times higher than densities in comparable habitats with moderate fishing pressure near Lee Stocking Island. It is widely believed that harvest of juveniles and illegal harvest by foreign commercial fishing interests is a significant problem.
There is little data available in The Bahamas to adequately advise management decisions. It is clear new management strategies are necessary, but progress toward development and implementation of these strategies has been hindered by lack of funding, research, and general support. The effectiveness of any new regulation is questionable without sufficient enforcement efforts, a considerable obstacle considering the geographic extent of The Bahamas and the capacity of officials to maintain a presence in fished areas.
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