About me
Characterizing the Diet and Trophic Ecology of the Atlantic Guitarfish
Location: East Ballroom
Mentor: Dr. Catherine Macdonald
Globally over two-thirds of all chondrichthyan species are threatened with extinction and guitarfish (Rhinobatidae sp.) are among the most threatened families within this group. Atlantic guitarfish (Pseudobatos lentiginosus), a species of nearshore mesopredatory ray and the only guitarfish species found in Southeast Florida, play an important role in local food webs, managing populations of prey species and acting as a potential food source for larger coastal predators. In this way guitarfish form a crucial trophic and energetic link between benthic food webs and broader interconnected habitat mosaics. Despite the importance of such ray species to nearshore ecosystems, the diet and trophic ecology of Atlantic guitarfish has yet to be described and represents a critical gap in our understanding of this Vulnerable species. This project presents the first characterization of Atlantic guitarfish diet and trophic ecology, constructed via the stable isotope analysis of Southeast Florida guitarfish tissue samples. We observed that neither sex nor body size (43‒70 TL) had a significant effect on isotopic signature and that Atlantic guitarfish are typically generalist feeders with a slightly higher consumption of fish groups compared to invertebrates. These novel findings help to characterize the important ecological role Atlantic guitarfish play in their environments, and can contribute to the informed management and conservation of other threatened ray species and nearshore hardbottom habitats they rely on.
