Semi-wild mariculture of the Caribbean King Crab, Maguimithrax spinosissimus

In this phase of the quarry project, we continued evaluating the abiotic and biotic characteristics of two quarry systems located in the Lower Florida Keys (Cudjoe Key, FL) for their potential use in the semi-wild mariculture of the Caribbean King Crab (Maguimithrax spinosissimus). Abiotic conditions in both quarries are suitable to support crab populations throughout the year. We deployed five habitat designs in February 2025, and by April 2025, we saw our first four adult male crabs. From April 2025 to March 2026, we observed 36 adult crabs on the artificial structures. Statistical modeling showed that the probability of crab presence on the structures increased significantly over time. This suggests that as the structures get more mature, their suitability for M. spinosissimus to inhabit them would increase. Our work has shown promising results, so we recommend continuing monthly monitoring of quarries and new habitats, as well as crab relocation, to assess the project's feasibility. Additionally, we encourage an exploratory study of other quarries along the Florida Keys to determine their current Caribbean King Crab populations and their associated abiotic characteristics. Given the promising results of our new habitats as a potential boost to the crab population, we could potentially use other quarries (e.g., Marathon, Tavernier, Key Largo) for this purpose. Besides higher total crab production, the benefits of using multiple quarries from Key West to Key Largo encompass a reduction in transportation time (from the quarry to the reef restoration site) and increased genetic diversity.