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Characterization of species distributions is a fundamental challenge in biodiversity science, with particular significance for downstream evolutionary studies, conservation efforts, field-based faunal studies and estimates of species diversity. Checklists and phylogenetic studies often focus on poorly known, rare taxa with limited ranges. However, studies of widely distributed, ecologically important species that are abundant in their preferred microhabitats are also important for systematics and local conservation efforts, but less often studied. We collected novel natural history data during fieldwork (2019–2023) for Philippine populations of bockadams (Homalopsidae:Cerberus), one of the most abundant vertebrates in Southeast Asian aquatic systems. Considered a coastal snake, many studies reportCerberusinland. We report the frequency of encounters ofCerberus schneiderii, and the IUCN data-deficient, Philippine-endemicCerberus microlepisduring six expeditions (62 days; 1041 person-hours). We report new occurrence data for 69C. schneideriiand6 C. microlepisfor coastal and inland populations, water measurements and dietary observations. Regression analyses and ecological niche models show the importance of coastal and mangrove habitats forCerberus. Our study is the most comprehensive assessment of PhilippineCerberuspopulations to date and provides critical baseline natural history data for downstream research on widespread and range-restricted species of Southeast Asian snakes.
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Profiling abundance, size, and shell utilization patterns of Coenobita clypeatus (Fabricius, 1787) (Decapoda: Anomura: Coenobitidae) in protected and highly frequented beaches in Puerto Rico
Abstract The coastal Caribbean is a well-known harbor for biodiversity, yet it is mainly valued for its ample resources and services. Economic interests typically supersede conservation efforts, introducing anthropogenic-related factors such as noise, chemical pollution, and geographical disturbances into the littoral zone, where ecological diversity is abundant. Although human activity is known to be detrimental to biodiversity across habitats, the effect of conservation measures that limit anthropogenic activity on coastal populations remains understudied. To measure the benefit of conservation in the littoral environment, we sampled populations of the hermit crab Coenobita clypeatus (Fabricius, 1787) of highly frequented (non-protected) and protected beaches in northern Puerto Rico. We profiled 1,119 individuals by using transects, describing their size and shell utilization patterns during winter and summer. The C. clypeatus population was larger (P < 0.0001 during both seasons) and more abundant (P = 0.0006 during winter, P < 0.0038 during summer) in the protected beach than in the non-protected beach, with no effect of season. Shell utilization patterns were more consistent in the protected beach, likely due to the greater availability of gastropod shells. These results suggest that the conservation measures implemented in the protected beach promote the survival, reproduction, and growth of hermit crabs in the location. Expansion of protected habitats through governmental and civilian efforts should enhance the conservation of the biodiversity of protected areas.
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- Award ID(s):
- 1736019
- PAR ID:
- 10427921
- Date Published:
- Journal Name:
- Journal of Crustacean Biology
- Volume:
- 42
- Issue:
- 3
- ISSN:
- 0278-0372
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/jcbiol/ruac048
