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This study employs dynamic occupancy modeling to assess the status of the Critically Endangered Bermuda skink (Plestiodon [= Eumeces] longirostris) on Bermuda, considering occupancy, colonization, local extinction, and detectability over time. Over a 2-year period, surveys were conducted at 40 locations across the island, with a focus on previously unsurveyed areas.

Key Findings:

1. Occupancy and Distribution: Skinks were detected at 13 sites (32.5%) during the surveys, including two new records. They tend to occupy islands with rocky coastal habitats and prickly pear cacti.

2. Drivers of Occupancy Dynamics: Site characteristics associated with skink occupancy include island status, rocky coastal habitat, and the presence of prickly pear cacti. The absence of seabirds and the presence of cats were linked to reduced local extinction risk.

3. Detectability: The probability of detecting skinks was 0.42 (95% CI: 0.31–0.53), requiring, on average, five surveys per site to reliably detect their presence with 95% confidence. Cat and rat predators were found to hinder detection.

4. Conservation Implications: Dynamic occupancy models provide insights into the drivers of skink occupancy dynamics, aiding conservation management. The survey effort needed to monitor population changes over time can be estimated from detectability rates.

Conclusion:

Dynamic occupancy modeling offers a robust approach for monitoring cryptic and threatened species like the Bermuda skink, helping to make informed conservation decisions by considering both occupancy and colonization/extinction processes.