Zoological Studies

Vol. 39 No. 3, 2000

Resource Limitation Underlying Reproductive Strategies of Coral Reef Fishes: A Hypothesis

Rong-Quen Jan

Institute of Zoology, Academia Sinica, Taipei, Taiwan 115

Rong-Quen Jan (2000) A wide variety of complex spawning systems occurs in coral reef fishes. Among them, the demersal spawners and pelagic spawners are dominant in terms of both numbers of taxonomic groups and individuals. Here I propose a hypothesis to explain the reproductive strategies of these demersal and pelagic spawners. This hypothesis is based on 2 primary assumptions: that coral-reef fishes are selected to spawn demersal eggs; and that the nesting resource (i.e., substrate) is limited in the environment. Thus re- source limitation is assumed to be the prime factor accounting for different spawning strategies. This hypothesis postulates that fishes which succeed in obtaining appropriate nesting substrates will spawn demersally, whereas those that fail to obtain suitable sites tend to spawn pelagically. Predictions from this resource-limitation hy- pothesis are in accord with many aspects of the available data. Therefore this hypothesis might be proposed as an alternative to established hypotheses to explain how different spawning patterns of coral reef fishes have occurred.

Key words: Damselfish, Nest, Reproduction, Spawning, Territoriality.

*Correspondence: Tel: 886-2-27899519. Fax: 886-2-27858059. E-mail: rqjan@ccvax.sinica.edu.tw