BIODIVERSITY OF SHALLOW REEF FISH ASSEMBLAGES IN WESTERN AUSTRALIA USING A RAPID CENSUSING TECHNIQUE

WA Museum Records and Supplements | Updated 1 decade ago

 Abstract - A rapid assessment methodology was used to provide relative abundance data on selected families of Western Australian fishes. Twenty shallow water reef sites were surveyed covering the coastline between the Recherche Archipelago in the south east and the Kimberley in the north. Three groups of atolls located off the Kimberley coast were also included. Eighteen families that best represent the State's nearshore reef fish fauna were targeted. They are: Serranidae, Caesionidae, Lutjanidae, Haemulidae, Lethrinidae, Mullidae, Pempherididae, Kyphosidae, Girellidae, Scorpididae, Chaetodontidae, Pomacanthidae, Pomacentridae, Cheilodactylidae, Labridae, Odacidae, Acanthuridae, and Monacanthidae. Analysis of the dataset using a hierarchical classification technique indicates that four groups of reef fishes are present: a southwest assemblage, a northwest assemblage, an offshore atolls assemblage, and a Kimberley assemblage. The first assemblage is comprised mainly of temperate species, while the latter three are mostly tropical fishes; these two broader groupings narrowly overlap on the west coast between Kalbarri and the Houtman Abrolhos. Evidence of a wide zone of temperate/tropical overlap-as proposed by some previous studies-is not supported by this analysis, nor is the presence of a prominent subtropical fauna on the west coast. Ecological differences of the four assemblages are explored, as well as the impact by the Leeuwin Current on this arrangement.