INTRASPECIFIC AND INTERSPECIFIC AVOIDANCE OF AREAS MARKED WITH SKIN EXTRACT FROM BROOK STICKLEBACKS (CULAEA-INCONSTANS) IN A NATURAL HABITAT

The detection of a chemical alarm pheromone may allow receivers to avo id areas where a predator has captured the prey's conspecifics. We mar ked minnow traps with either brook stickleback (Culaea inconstans) ski n extract or a control of distilled water and tested whether stickleba cks avoided the skin extract marked traps in a natural habitat. Signif icantly more sticklebacks were captured in traps marked with control w ater, thereby demonstrating avoidance of conspecific skin extract. The stickleback captured in traps marked with conspecific extract were si gnificantly smaller than those captured in traps marked with control w ater, implicating ontogenetic factors (i.e., experience or physiologic al development) in the development of the response. We also captured s ignificantly fewer finescale dace (Chrosomus neogaeus) and fathead min nows (Pimephales promelas) in traps marked with skin extract. These da ta suggest that dace and minnows may benefit by avoiding areas where p redators have recently captured sticklebacks.