[Truncated abstract] The goal of this work was to investigate the finescale habitat associations and determine the effect of human impacts on coral reef fish assemblages. Initially I investigate how finescale spatial habitat variation influences the distribution and abundance of coral reef fishes. Significant variation in the reef fish assemblage was driven by variation in habitat. Consequently finescale habitat variation needs be accounted for in spatial or temporal surveys of coral fish assemblages. My second question investigated how protection from fishing influences the overall variation in coral reef fish assemblages, while my third question investigated how consistent the differences in protected fish assemblages are through time. Protection from fishing accounted for significantly more variation in fish assemblages than that explained by finescale habitat alone. This was driven by an average abundance and length of target species being higher inside sanctuaries and a response in non-target species indicating that there are some trophic interactions occurring between fishes. I found that both target and non-target species can be more abundant at protected reefscapes through time, consistent with the theory that protected areas can achieve recovery and lasting maintenance of fish assemblage structure relative to adjacent fished locations. I also investigated how fish assemblages within shallow coral reef habitats differ to those of adjacent continental shelf habitats to a depth of 100m. Cross-shelf sampling produced significant new knowledge on the depth and habitat specificity of many species previously only known from shallow coral reef environments. Many target species protected by shallow water protected areas are found as adults in unpotected shelf waters suggesting shallow water protected areas alone may not be effective for all species equally.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2012|