Occurrence of Gavialis gangeticus in the Lower Ganges of Bangladesh: urgent need for conservation initiatives

Abstract

The gharial, Gavialis gangeticus, a Critically Endangered fish-eating crocodilian native to the Indian subcontinent, has long been considered nearly extirpated from Bangladesh, with records largely limited to incidental captures in fishing gear. This study documents recent occurrences of G. gangeticus along a 100-km stretch of the Lower Ganges (Padma River) in northwest Bangladesh based on local ecological knowledge collected through a participatory monitoring approach conducted between 2018 and 2025. Eight individuals, including six yearlings, one hatchling and one adult, were recorded as accidental captures. An additional four individuals, including two yearlings, one hatchling and one adult, were directly observed on riverine chars. Occurrence records were spatially clustered around sandbar-associated habitats in the Godagari region, suggesting the presence of suitable microhabitats. The repeated detection of individuals indicates the possible persistence of the species in the region, either through localised recruitment or dispersal from upstream populations. However, the absence of systematic monitoring and the prevalence of fisheries interactions highlight significant threats and knowledge gaps.