Short term temporal variation of mangrove fish assemblage in Chabahar Bay (Oman Sea)

Abstract

This study aimed to assess the temporal variation in fish assemblage in Chabahar Bay mangrove habitat. Baited Remote Underwater Video (BRUV) sampling method was applied to record the fish presence. Fishes were sampled monthly from June 2017 to April 2018 at daylight time (9:00 to 14:00) during high tide. Water temperature, turbidity, and salinity were recorded at the time of sampling. During the study, a total of 17 species belonging to 12 families were identified. A mbassis gymnocephalus was found as the dominant fish throughout the year except in November and December. The most abundant fish fauna in numbers was characterized by the following five species: Ambassis gymnocephalus (53.38%), Sardinella sp. (17.13%), Terapon jarbua (4.79%), Rhabdosargus sarba (3.25%) and Acanthopagrus berda (2.9%). ANOSIM showed that significant differences in the assemblage structure occurred among months (R=0.613, P < 0.001), and the CLUSTER analysis, together with the SIMPROF test showed that December is significantly different in term of fish assemblage. Canonical Correspondence Analysis (CCA) on species-environment correlations revealed that temperature and turbidity were the main parameters influencing fish occurrence in the mangrove habitat of Chabahar Bay. The overall diversity (Shannon–Wiener, Simpson’s Index of Diversity, and Pielou’s evenness), as well as functional diversity indexes (FRic and FDis), was higher in autumn and spring pointing out that the diversity is higher when the temperature had the closest value to averaged value.