Environmental drivers and ecological implications of a ctenophore swarm: a case study from the Bay of Bengal, northern Indian Ocean

Abstract Ctenophores are quick responders to coastal environmental changes and play a crucial role in marine food web dynamics. We report the drivers of ctenophore swarm (Pleurobrachia spp.) associated ecological estuarine waters Sundarbans mangrove–estuarine complex northern Bay Bengal (BoB). Plankton fish samples were collected from at peak outflow northeast monsoon (NEM). Sampling locations mouth witnessed ctenophores pileus Pleurobrachia globosa) swarming proportions. Multivariate statistical analysis revealed significant differences hydrographical biological properties between non-swarm areas. The sea surface salinity, ammonium, mesozooplankton (MSP) density positively correlated while microzooplankton (MCZ) was negatively with swarm. Fish caught locations, dominated by microbial consisted species less market value, those conventional plankton mainly commercially important species. Thus, first-ever record fishing ground BoB, this study provides evidence how ‘dead end’ predator affects organization fisheries tropical waters.