“Never Give a Sucker an Even Break”

Abstract

Abstract Suckers are thought to be harmful to other species of fish because of predation on eggs and fry and from competition, mainly for food. This belief has led to many sucker removal projects to enhance sport fisheries. In a review of the literature, we found that (1) although suckers eat eggs and fry of some fishes, there was no evidence that such predation is harmful to prey populations; (2) studies suggesting competition for food failed to demonstrate that food was limiting (which is necessary for competition to occur); (3) evidence is equivocal that sport fish populations fare better in the absence of suckers or after sucker removal programs. Reasons for the poor evidence that suckers are detrimental are the complexity of species interactions in aquatic communities, particularly interactive segregation (Nilsson 1967), as well as the lack of removal projects in which sucker removal alone was the sole variable. Guidelines are suggested for studies designed to elucidate the role of suckers in fish co...