Objective
The primary objective of the Little Bahama Bank expedition was to survey the density, abundance and population structure of queen conch stocks in the shallow commercial fishing grounds from West End, Grand Bahama north to the Mantanilla Shoal and east to Marsh Harbour, Abaco. A secondary objective of the trip was to collect queen conch tissue samples for a collaborative project with the Smithsonian Institute. The details of this study and preliminary results are not included in this report.
Findings
- Average density of flared-lip queen conch (“adults”) over the Little Bahama Bank was 30 “adults”/ha (no. per hectare = no./10,000 m2).
- The highest “adult” conch densities were found on the Mantanilla Shoal (69/ha) and near Carter’s Cay (49/ha).
- Most locations had much lower densities of adults between 3.5 -34 adults/ha.
- Sub-adult densities were low throughout the survey area with an average value of 8.3/ha.
- Mating pairs were observed in just 21 of the 215 kilometers surveys throughout the study area.
- The average shell length (205 mm) was consistent and slightly larger than average shell lengths in other surveyed regions.
- The oldest (thickest lipped) adults were found within the least exploited population on the Mantanilla Shoal. Other surveyed population on the Little Bahama Bank were on average much younger with shell lips averaging 5-15mm.
- The estimated total abundance of adults on the LBB was 1.96 million and roughly 500,000 subadults.
- The survey results of the LBB provide more evidence for a clear trend for local conch populations to be overfished to densities incapable of reproduction and for densities to increase with distance from human settlements. The best example of a fully functioning population other than in the Exumas Cays Land and Sea Park is the significant adult breeding population in the most remote part of the Jumentos Cays.
Recommendations
This overview of the current status of conch resources in the Bahamas leads to the following recommendations:
- Establish a network of marine protected areas (MPAs), fishery cooperatives and a sustainable fishery certification program.
- Protect southern conch populations from international poachers.
- Update regulations especially those related to minimum lip thickness at harvest, use of hookah (compressed air) and the importance of seasonal closure.
- Develop area specific management plans for each major conch resource with harvest quotas.
- Evaluate the impact of ending export.
- Research population connectivity using molecular genetics and the impact of discarding knocked conch in active fishing grounds.