Diversity and distribution of fish fauna in the Ib River, a tributary of Mahanadi, India

Abstract

Ichthyofaunal survey was conducted in the Ib River (21°44’ to 22°50’ N; 83°56’ to 83°54’ E), an important tributary of Mahanadi, to evaluate the diversity and distribution of freshwater fishes along six sites on seasonal basis between February, 2016 and January, 2017. A total of 55 species belonging to 42 genera, 21 families and 9 orders were recorded from the study area. Maximum number of species belonged to the Order Cypriniformes (41.8%) followed by Siluriformes (21.8%) and Perciformes (21.8%). Maximum value of species richness was observed in downstream areas; Sundargarh and Barghat and least in upper stretches of Pamsala. Shannon–Weiner diversity index ranged between 2.47 to 3.68 at the six sites of Ib River indicating healthy state of the river. Bray-Curtis similarity cluster analysis suggests that similarities between sites decrease with increasing distance, with highest similarity found between Sundargarh and Barghat sites. Baseline data on fish biodiversity has been generated in this study which can now be periodically monitored and form basis for future conservation plans.

Evaluating the influence of environmental variables on the length-weight relationship and prediction modelling in flathead grey mullet, Mugil cephalus Linnaeus, 1758

“…River inflows create highly energetic and dynamic sedimentary environments with excellent spatial and temporal gradients in physical parameters like salinity and suspended sediment concentration ( Dyer, 1997 ). Increased sediment concentration eventually leads to increased turbidity and conductivity, reducing the habitat suitability for fish occurrence and growth ( Chandran et al, 2019 ). This could be why Kakdwip was recommended as an outlier location in the present study.…”

Quantification of morphological variations among populations of Channa gachua (Hamilton, 1822) from different geographical locations in India

“…However, such variations may be affected by differential habitat use, especially the use of different ecological niches with food availability in the ecosystem, feeding regimes and physicochemical parameters of the water (Hegrenes, 2001;Khan, et al, 2013). The larger size of head, snout and jaws in the population of GP may be results of fast flowing water and big prey feeding behaviour which reasonably correlated to the abundance of bigger preys in fast moving waters (Deepa, et al, 2009;Chandran, et al, 2019) as most of the specimens were collected from the Ganga River. In PC2, the positively correlated variables were snout length, the gap between dorsal fin and caudal fin and gap between anal fin and caudal fin, which showed variations in the caudal peduncle region, while negatively correlated variable was dorsal fin base length.…”