Assessing Genetic Variation and Population Connectivity in Wallago attu: A Call for Enhanced Conservation Measures.

Exploited fish species are experiencing population decline and environmental changes due to human activities. As populations decline, genetic diversity may decrease, potentially resulting in a reduced ability to adapt to current and future ecological shifts. The prominent freshwater fish species, Wallago attu, faces extinction threats and has recently been classified as Vulnerable on the IUCN Red List. Little is known about the species' genetic and population dynamics, despite the economic importance in the region. The study aimed to use microsatellites to gather baseline genetic and population data and assess the effect of water management practices on population structure. The study revealed low-to-moderate genetic diversity within sample localities but significantly high differentiation among populations. Findings indicated significant inbreeding within populations and strong evidence of recent bottlenecks. Genetic relatedness analysis, a UPGMA dendrogram and Bayesian clustering, clearly divided the populations into two clusters, which suggests a significant genetic divergence. Anthropogenic activities and water management strategies significantly influenced the genetic population structure in the studied regions. To ensure the long-term survival of this vulnerable species, conservation-oriented management should prioritize preserving current genetic diversity, given its distinct genetic patterns.