Diversity and assemblage pattern of finfish and shellfish along the Sitakunda coast, Bay of Bengal

Abstract

Finfish and shellfish diversity at three sampling sites of the Sitakunda coast of the Bay of Bengal were studied monthly from March 2016 to February 2018, wherein 355181 fishery individuals were enumerated from 554 catch samples collected by 13 different types of gears. Out of a total of 168 fish species identified, 124 were finfish species (13 orders and 47 families), and 44 were shellfish species (2 orders and 8 families). The order Decapoda (65.17 %) occupied the highest position, followed by Perciformes (20.59 %), Scopeliformes (5.37 %), Clupeiformes (4.97 %), Siluriformes (1.35 %), Pleuronectiformes (1.18 %) and the remaining 9 orders contributed only 1.36 % of the total sampled population. Oxyurichthys keiensis is reported as a new record for Bangladesh. The highest numbers of individuals during pre-monsoon were recorded at Station II, and the lowest numbers of individuals from Station III during the post-monsoon season. Diversity indices showed no significant difference across years, but a significant differences were observed among stations. Stations I and II showed comparatively higher species abundance and diversity. According to the evenness index, the population of Station II was the most stable among the three stations. Analysis of Similarity (ANOSIM), Similarity Percentage Analysis (SIMPER), cluster analysis, and non-metric multidimensional scaling revealed clear differences in species populations across seasons.