A study of diversity, distribution and habitat preferences of nudibranch in Redang Island

Abstract

The aim of this study is to observe and identify the diversity of the nudibranch, to observe the distribution and habitat preferences of the nudibranchs and also to estimate the species abundance in Redang Island. The sampling was divided into two methods; the 0.18m2 photoquadrat analysis by Coral Point Count with Excel extension (CPCe) and survey (questionaire) survey that is distributed to dive centres in Redang Island. The species diversity and distribution are analyzed using the ecological indices which are Shannon-Weiner Index and Pielou Evenness Index. The habitat preferences is analyzed using One Way ANOVA and Post Hoc Tukey test (P<0.05). Overall, there are 21 species of nudibranchs from IO genus and seven families of nudibranchs found from 24 dive sites in Redang Island. The most dominant families found are family Chromodorididae and Phyllidiidae with a total of seven and six species respectively. The species that are most abundant is Phyllidiella pustulosa from family Phyllidiidae and Chromodoris bullocki from family Chromodorididae. In terms of diversity, Terumbu Kili and Tunnel point are highest in number of different species. Pulau Kerengga and Mak Cantik on the other hand house the most nudibranchs in general. The habitat preference for nudibranchs in Redang Island is mostly coralline algae and macroalgae