ASFB Home > The effects of spatial and temporal factors on the abundance of seven key finfish species along south-western Australia.

Consumption of coral propagules enhances the quality of larvae from a planktivorous fish

Mark McCormick

James Cook University, TOWNSVILLE, AUSTRALIA

THEME: ASFB

The synchronized spawning of corals in many parts of the world represents a huge injection of biological material into the waters around reefs. Much of this material is consumed by fishes and filter-feeding invertebrates in the 4 or so days following spawning. The present study is the first to attempt to document the flow on effects of coral spawning for a facultatively planktivorous fish population. The study compares two lagoonal populations of the damselfish Pomacentrus amboinensis that fed to differing degrees on coral spawn for 5 days after the December 2001 mass spawning. A NW wind blew coral slicks over the outer lagoon (site 1) to the inner lagoon (site 2) some 1.5 km away. Behavioural observations 2-5d after spawning showed a significantly higher proportion of P.amboinensis were feeding in the windward site, than the inner lagoonal site. To quantify the effect of the high lipid diet on the population, the body condition of females collected 5d after coral spawning from both sites were compared to samples collected from the same sites 2 months later. The reproductive output of females from each site was monitored and larvae were collected at hatching to compare morphology. Attributes of the larvae were compared to larvae collected from the same locations outside the coral spawning period and larvae from experimentally fed fishes. Evidence suggests that females gain a fitness advantage from feeding on coral spawn and this is passed on the their offspring. this abstract is for ASFB larval section.