Effective Timing of Male Courtship Displays for Female Mate Choice in a Territorial Damselfish Stegastes nigricans

Abstract

The timing of female mate choice and the frequency of male courtship displays were investigated in a territorial damselfish, Stegastes nigricans, in Okinawa, southern Japan. Both males and females of this species held individual territories, which were distributed contiguously, forming colonies. Females visited male territories to spawn in the early morning, males subsequently tending the eggs until hatching. Females were visited by a higher number of males in the morning and evening of the day prior to spawning than on other days and received courtship displays more frequently on the morning of spawning and the previous day. Females often began spawning before male courtship displays in the morning, tending to spawn with males that had courted most frequently on the previous day. This indicates that female mate choice was usually based on the previous day's frequency of courtships. Females that were courted less frequently on the day prior to spawning began to spawn later in the morning in order to receive a greater number of courtship displays. Accordingly, males frequently courting such females on the morning of spawning as well as on the previous day, should increase their chances of mating success.