Mating system of the freckled hawkfish, Paracirrhites forsteri (Cirrhitidae) on Kuchierabu-jima Island reefs, southern Japan

Abstract

The mating system of cirrhitids is generally classified as harem polygyny. However, detailed information on the spatial distribution patterns and mating relationships is lacking in large hawkfish species. We investigated the spatial distribution patterns and mating relationships among individuals of the large hawkfish, Paracirrhites forsteri, on a Kuchierabu-jima Island reef in southern Japan. Large males maintained territories and attacked other large males near the boundaries of their territories. Females usually stayed outside of male territories during the day and moved to prominent coral heads within male territories during the late afternoon for mating. Large males spawned with several females around sunset, and females seldom changed their mating partners. In addition, we confirmed the occurrence of small males with a body size similar to that of females. These small males placed their territories against other small males within/around the territories of large males and pair-spawned with small females. The female distribution pattern and occurrence of small males have never been reported in haremic hawkfish, but their stable mating partnership is very similar to that of haremic hawkfish. Our results reveal considerable variation in mating systems within Cirrhitidae.