Faunal Diet of Adult Cane Toads, Rhinella marina, in the Urban Landscape of Southwest Florida

SIMPLE SUMMARY: Urban ecosystems provide habitat to many species, including invasive species such as the cane toad (Rhinella marina) that is particularly successful in human-altered landscapes. There have been numerous investigations of the cane toad diet, but most of these studies identified prey items at lower taxonomic resolutions (i.e., order or family). We used higher resolution for prey identification and multiple dietary measures of prey consumption to assess the ecological role of cane toads in the urban landscape of southwest Florida. Prey taxa commonly considered urban pests dominated the diet of cane toads inhabiting golf course communities, and there were differences in prey consumed during the wet and dry seasons of this region. We provided a better understanding of the potential relationships between cane toads and their prey in the urban environment. ABSTRACT: We investigated the diet of cane toads (Rhinella marina) inhabiting urbanized areas in southwest Florida to provide high taxonomic resolution of prey items, contrast toad diets between sampling seasons and sexes, and assess this invasive species’ ecological role in the urban landscape. A pest control agency collected cane toads from two golf course communities in Naples, Florida, USA during November–December 2018 (early dry season) and June–July 2019 (early wet season), and faunal stomach contents were quantified from a random subsample of 240 adult toads (30 males and 30 females from each community and season). Yellow-banded millipedes (Anadenobolus monilicornis), big-headed ants (Pheidole spp.), and hunting billbugs (Sphenophorus venatus vestitus) were the most frequently consumed prey items and had the highest total numbers and/or volume with corresponding highest indices of relative importance. There was considerable overlap in the seasonal prey importance values for each golf course community and little if any difference in the importance values between toad sexes in each community. Nonetheless, big-headed ants were the most important prey in both communities during the wet season, while yellow-banded millipedes were the most important dry season prey in one community and hunting billbugs the most important in the other. Despite limited spatiotemporal sampling effort, our results indicated that cane toad was consuming arthropod taxa considered pests in the urban ecosystem. Further studies are needed to investigate the potential effects of human activities and environmental variability on the cane toad diet and to determine whether cane toads act as a biological control for pest populations.