Identification of Bottlenose Dolphin Prey Within the IRL, Utilizing Images Collected During Observed Dolphin Feeding Behaviors

Identification of dolphin prey is fundamental to understanding the ecological function of dolphins within the Indian River Lagoon (IRL), and useful in determining shared resources and associated health risks among dolphins and humans. This study utilized 62 images of dolphin prey documented during observed feeding behaviors from 2003 to 2015 to determine prey of significance. Dolphin prey were comprised of: 44% mullet (Mugil spp.), 11% jack (Caranx spp.), 10% pinfish (Lagodon sp.), and 6.5% menhaden (Brevoortia spp.). The remaining 28.5% of prey were comprised of 11 genera, and no spatial or temporal differences among prey were found. The majority (87%) of the genera of fishes documented as dolphin prey are also targeted by local fisheries for human consumption, bait, and sport. Understanding the prey habits of this apex predator can be useful in determining management and conservation strategies for local fisheries and ecosystems, and identifying possible vectors for bioaccumulation of contaminants.