title: Field verification of predator attraction to minnow alarm substance.
abstract: Fishes such as minnows in the superorder Ostariophysi possess specialized alarm substance cells (ASC) that contain an alarm cue. Alarm substance can only be released by damage to the epidermis; thus, the release of alarm substance is a reliable indicator of predation risk. When nearby minnows detect the cue, they adopt a range of antipredator behaviors that reduce their probability of predation. Predator-predator interactions afford prey an opportunity to escape and, thus, a fitness benefit that maintains alarm substance calls over evolutionary time. Here, we present data from a simple field experiment verifying that nearby predators are attracted to minnow alarm substance because it signals an opportunity to pirate a meal. Fishing lures were baited with sponge blocks scented with either (1) water (control for sponge odor and appearance), (2) skin extract from non-ostariophysan convict cichlids (superorder Acanthopterygii, Archocentrus "Cichlasoma" nigrofasciatus) to control for general injury-released cues from fish, or (3) skin extract from fathead minnows (superorder Ostariophysi, Pimephales promelas). Predator strike frequency on each sponge type was 1, 1, and 7 for water, cichlid, and minnow cues, respectively. These data provide the first field test using fish predators of the predator-attraction hypothesis for the evolution of Ostariophysan alarm substance cells.
authors.affiliation: Biology Department, Minnesota State University, Moorhead 56563, USA. wisenden@mnstate.edu
authors.forename: Brian D
authors.initials: BD
authors.lastname: Wisenden
authors.forename: Travis A
authors.initials: TA
authors.lastname: Thiel
mesh_terms: D000222:Adaptation, Physiological; D000819:Animal Communication; D000818:Animals; D023681:Cichlids; D003530:Cyprinidae / Q000502:physiology*; D010675:Pheromones / Q000494:pharmacology*; D011235:Predatory Behavior; D012867:Skin / Q000737:chemistry
chemical_list: D010675:Pheromones