Benthic macrofauna of the bay and adjoining waterways of jambu and kharnasi odisha east coast of India

Abstract

In the state of Odisha, on the east coast of India, mangrove estuarine habitats are either understudied else unexplored for macrobenthos. Hukitola Bay and the adjoining Jambu and Kharnasi waterways in the Mahanadi estuarine system, south of the Bhitarkanika National Park and Gahirmatha Marine Wildlife Sanctuary (quotarribadaquot of Olive Ridley turtles), is one such region. Given the steady anthropogenic interferences and the absence of reliable information on macrobenthos, environmental assessment of the Bay was imperative. Therefore, the study s main objective was to address the gaps in knowledge by providing taxonomic and ecological information on the macrobenthos of the region under consideration. Furthermore, this work aimed to assess the influence of environmental variables on macrobenthic assemblage patterns. The study was designed to seasonally sample 10 GPS fixed points in the Bay environment for the macrobenthic epifauna, water, and sediments for a year (2019). Results revealed 78 species from five major taxa, namely Mollusca (65%), Arthropoda (28%), Annelida (3%), Echinodermata (3%), and Brachiopoda (1%). Findings indicated significant numbers of the placunid Placuna placenta, potamid Pirenella cingulata, and venerid Paratapes textilis. The mangrove-fringed regions had a higher density of fauna than other areas due to the outwelled nutrient-rich waters from mangroves that proved advantageous for the colonization and sustenance of a few species, for example, Pirenella cingulata Placuna placenta, Paratapes textilis, and Tegillarca granosa. In contrast, a wider variety of species could be observed in the outer bay, newline