Am. Friedlander et Jd. Parrish, HABITAT CHARACTERISTICS AFFECTING FISH ASSEMBLAGES ON A HAWAIIAN CORAL-REEF, Journal of experimental marine biology and ecology, 224(1), 1998, pp. 1-30
Habitat characteristics of a reef were examined as potential influence
s on fish assemblage structure, using underwater visual census to esti
mate numbers and biomass of all fishes visible on 42 benthic transects
and making quantitative measurements of 13 variables of the correspon
ding physical habitat and sessile biota. Fish assemblages in the diver
se set of benthic habitats were grouped by detrended correspondence an
alysis, and associated with six major habitat types. Statistical diffe
rences were shown between a number of these habitat types for various
ensemble variables of the fish assemblages. Overall, both for complete
assemblages and for component major trophic and mobility guilds, thes
e variables tended to have higher values where reef substratum was mor
e structurally or topographically complex, and closer to reef edges. W
hen study sites were separately divided into five depth strata, the de
eper strata tended to have statistically higher values of ensemble var
iables for the fish assemblages. Patterns with depth varied among the
various trophic and mobility guilds. Multiple linear regression models
indicated that for the complete assemblages and for most trophic and
mobility guilds, a large part of the variability for most ensemble var
iables was explained by measures of holes in the substratum, with impo
rtant contributions from measured substratum rugosity and depth. A str
ong linear relationship found by regression of mean fish length on mea
n volume of holes in the reef surface emphasized the importance of she
lter for fish assemblages. Results of this study may have practical ap
plications in designing reserve areas as well as theoretical value in
helping to explain the organization of reef fish assemblages. (C) 1998
Elsevier Science B.V.