Mate choice and size assortative pairing by the cichlid fishes of Lake Jiloá, Nicaragua

Abstract

Size‐assortative mating occurs for all six substratum‐spawning cichlids studied in Lake Jiloá, Nicaragua. Mate quality is clearly a dominant consideration for both sexes, as larger pairs had disproportionately more young surviving beyond 3 weeks. Mating with the largest available mate should generally be advantageous to both sexes, since the success of a pair is dependent on their ability to take and defend a territory. A model involving mate discrimination by both partners is developed and contrasted to models involving single sex discrimination with intrasexual competition.