Rfg. Ormond et al., BEHAVIORAL-DIFFERENCES IN MICROHABITAT USE BY DAMSELFISHES (POMACENTRIDAE) - IMPLICATIONS FOR REEF FISH BIODIVERISTY, Journal of experimental marine biology and ecology, 202(1), 1996, pp. 85-95
There is considerable overlap in use of some resources among species w
ithin guilds of coral reef fish. Here, however, we describe two studie
s indicating behavioural differences in microhabitat use between speci
es of damselfish (Pomacentridae). Differential association with differ
ent microhabitats during normal foraging was investigated on fringing
reefs in the Egyptian Red Sea. Species present in reef quadrats were t
ested for an association with features such as substrate cover, coral
growth forms and extent of vertical faces. For 9 damselfish species di
scriminant functions were derived predicting their presence or absence
with success rates of 77 to 100%, implying marked association between
each fish species and a particular combination of substrates. The num
ber of damselfish species present was found to be highly correlated wi
th various reef characteristics, especially the number of coral growth
forms present. Differences in reef zone and substrate use for spawnin
g and nesting by 12 non-territorial damselfish species were investigat
ed in the Maldives. Overlap indices between each species pair for zone
and for substrate both showed a predominance of zero values. A combin
ed overlap index was also calculated; 83% had values lower than 0.5, c
onfirming a high degree of resource partitioning between species. Thes
e observations support the suggestion that behavioural differences in
habitat use between species may be significant in sustaining diversity
among coral reef fish.