Genetic mating patterns studied in pools with manipulated nest site availability in two populations of Pomatoschistus minutus

• DOI: 10.1111/j.1420-9101.2006.01114.x
• Publication Date: 2006-04-23T15:36:16Z
• Authors: A. Singer; C. Kvarnemo; K. Lindström; O. Svensson
• Keywords: Male; 0106 biological sciences; Competitive Behavior; Environment; Models, Biological; 01 natural sciences; Nesting Behavior; Perciformes; Sexual Behavior, Animal; Fertilization; Animals; Female; Selection, Genetic

Abstract Pomatoschistus minutus show paternal care in a resource defence mating system. We investigated the effect of nest-site availability on parasitic spawning. Each experimental pool contained four potentially nest-building males, four females and nests-sites in shortage (2) or excess (6). Both treatments were conducted in two populations; one with natural nest-sites in excess, one with a nest-site shortage. Microsatellite-DNA revealed that all nest-holders had fertilized most of the eggs they tended. Yet, 35% of the nests contained eggs fertilized by another male and 14.4% of the males had performed parasitic spawning. There was no site or treatment effect. Several females spawned in two nests, which coincided with parasitic spawnings, suggesting a cost to the nest-holder in terms of lost mating success. Nest-holders with and without eggs and non-nesting males all spawned parasitically, generating a significantly lower opportunity for sexual selection compared to if there had been no parasitic spawning.