We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Finfish harvest patterns in the largest Ramsar wetland—Vembanad estuary along the south-west coast of India
Summary
Researchers quantified finfish harvests across ten landing centres in India's Vembanad estuary from 2019–2020, documenting 867 tonnes of catch spanning 88 species, with gill nets dominating and five threatened species among the haul. This baseline fishery data is critical for understanding how microplastic contamination in estuarine systems may be entering the food chain through commercially harvested fish consumed by humans.
Quantifying the fish harvest from inland aquatic ecosystems is a major prerequisite for effective fisheries management. However, rigorous efforts are lacking in this direction due to erratic fishing patterns, isolated landing sites, and nonattendance of fishermen. Moreover, there is an urgent need of systematic evaluation of aquatic resources from Ramsar sites, which are wetlands of international importance. In this direction, the finfish harvest of the Vembanad estuary, a Ramsar site of international importance in Kerala state, India was estimated on a monthly basis from June 2019 to May 2020, covering ten major fish landing centres. The exploited finfish fishery was estimated as 867 tonnes, comprising 88 species from 48 families and 71 genera. Cichlids (19.50%), catfishes (12.40%), anchovies (10.10%), mullets (8.52%), and cyprinids (3.70%) were the major groups in the fishery. The landings included one endangered (EN) (Himantura uarnak) and 4 vulnerable (VU) (Rhizoprionodon acutus, Hyporhamphus xanthopterus, Channa diplogramma, and Horabagrus brachysoma) fish species. The major fish species in the fishery were Etroplus suratensis (90.46 t), Oreochromis mossambicus (65.56 t), Arius maculatus (57.97 t), Ehirava fluviatilis (56.34 t), and Stolephorus commersonnii (53.24 t). Gill nets (66.80%) were the dominant fishing gear in the estuarine fishery, followed by stake nets (21.32%), seine nets (6.70%), and Chinese dip nets (2.55%). The highest landings were recorded during the pre-monsoon season (40.43%), while the lowest during the monsoon (26.99%). The study revealed a decline (68%) in the finfish landings, from 2647.1 t (1988–89) and 1192.17 t (2012–13) to 867.13 t (2019–20), which might have been due to depletion of microhabitats and mangrove areas, compositional changes in water and soil, siltation, pollution, microplastics contamination, urbanization in the Kochi city, a reduction in estuarine area and mean depth, and over-exploitation. Therefore, there is an urgent need for management actions, including protection of natural microhabitats, mesh size regulation, the implementation of catch quotas and total allowable catch, artificial stocking of edible indigenous fish species, prevention or elimination of alien fish species and the declaration of fish protection zones, to protect the largest Ramsar site along the west coast of India.