Abstract

The queen conch has been harvested for thousands of years and overfishing has reduced populations in many areas, compromising its rates of reproduction. Long-range dispersal and mixing between distinct populations occur in the early life history stages, when pelagic larvae are transported by oceanic currents. As part of a status review conducted under the Endangered Species Act, we assessed how the population connectivity of conch changes with spatially variable patterns of fishing exploitation. Of the 39 jurisdictions analyzed, 14 were estimated to have densities that support reproductively viable population densities (>50 adult conch per ha). We simulated larval dispersal and compared the potential connectivity under an unexploited and a contemporary exploited reproductive scenario. Results demonstrate that reduced egg production, due to heterogeneous fishing pressure and localized depletion, significantly alters population connectivity patterns. For example, the Leeward and Windward Islands were estimated to be historically important for contributing larval input to other jurisdictions to the west; however, in the present day they are no longer expected to contribute larvae. Areas such as Turks and Caicos and Florida were estimated to historically have been highly reliant on external sources of larvae which are no longer viable in the present day. Some jurisdictions that historically acted as important connectors of genetic flow across the region (e.g., Dominican Republic, Haiti) have been overexploited, leading to breaks in the connectivity network across the species’ range. The results, which were published in peer review (Vaz et al. 2022), emphasize the need for regional and local management measures to maintain reproductively active populations across multiple jurisdictions.