Growth or reproduction: Intrasexual competition in a colonial damselfishStegastes nigricans |
| |
Authors: | Kenji Karino |
| |
Institution: | (1) Department of Biology, Tokyo Gakugei University, Nukui-kita, Koganei, 184-8501 Tokyo, Japan |
| |
Abstract: | Intrasexual competition within colonies of the damselfishStegastes nigricans was investigated. Both males and females held individual territories, and these territories were adjacently distributed,
forming distinct conspecific colonies with different size compositions. In both large and small colonies, only relatively
large individuals participated in reproduction. Breeding males and females left their territories to court, spawn and aggregate
more frequently than non-breeders of the same colonies. Breeders were less frequently attacked by other fish during these
excursions than were non-breeders. Most attacks were conducted by breeders of the same sex. This intrasexual aggression may
suppress the reproduction of non-breeders at least in large colonies. Non-breeders in large colonies had smaller gonads than
breeders of both large and small colonies, but they grew faster than breeders of the same body size in small colonies. This
suggests that non-breeders in large colonies allocate energy to growth in order to be reproductively competitive in the future,
although only a few of them remained in the same colonies upon maturity. Colony size thus has an effect on the reproductive
life histories of individual damselfish. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|