Resource use by and trophic variability of Armases cinereum (Crustacea, Brachyura) across human-impacted mangrove transition zones

• DOI: 10.1371/journal.pone.0212448
• Publication Date: 2019-02-15T18:30:07Z
• Authors: Erin Kiskaddon; Kiley Chernicky; Susan Bell
• Keywords: Isotope Analysis; Spatial heterogeneity

In Florida, resource use patterns by Armases cinereum (Armases), a highly abundant crab in coastal habitats, may serve as important indicators of habitat condition. Here we investigated feeding palm scrub forest to intertidal mangrove transition zones (transitions) well the relationship between disturbance and Armases' trophic position across three pairs geographically separated populations Tampa FL, USA. Each pair sites represented an unmodified "natural" location "disturbed" lacking upland terrestrial forested habitat. Laboratory experiments established baseline understanding preference offered strictly material sources at transition. In-situ behavior was examined using MixSIAR mixing models with δ13C δ15N stable isotope tracers. showed strong for consuming partially-decomposed from Avicennia germinans equally Iva frutescens. also displayed predatory under laboratory conditions, confirming omnivory presence material. Stable isotopes revealed pattern elevated disturbed habitats over paired natural locations. Diet reconstruction provided coarse resolution in-situ results show high spatial variation: appears rely heavily upon plant compared where it consume more animal prey. Combined, these findings support that diet indicate quality transitions southeastern United States.