Anti-predator defenses of Brown Bullheads (<em>Ameiurus nebulosus</em>) and interactions with Snapping Turtles (<em>Chelydra serpentina</em>)

Abstract

Ictalurid catfishes have sharp spines on their dorsal and pectoral fins that can be hazardous to predators. The pectoral spines may lock in an abducted position, effectively increasing body size and preventing ingestion by gape-limited predators. Further, sharp spines may injure predators or increase prey handling time, affording catfish opportunities for escape. As part of a long-term mark–recapture study of turtle ecology in Algonquin Provincial Park, Ontario, Canada, we documented the presence of Brown Bullheads, Ameiurus nebulosus, in the diet of Snapping Turtles, Chelydra serpentina. Here, we report on injuries inflicted by the pectoral spines of bullheads on Snapping Turtles during predator–prey interactions and provide a brief literature review of the functional significance and potential dangers of catfish pectoral spines to predators.