The 18th annual Vembanad Fish Count (VFC) recently concluded, revealing a worrying trend: only 61 species were recorded in the lake, comprising 58 finfish and three shellfish. This count represents a noticeable decrease from the previous year, highlighting escalating environmental challenges.
The extensive survey, organized by the Ashoka Trust for Research in Ecology and Environment-Community Environment Resource Centre (ATREE-CERC), mobilized approximately 110 volunteers. This diverse group included academics, researchers, and local fishers, all dedicated to assessing the health of Vembanad Lake’s southern regions near the Thanneermukkom bund. The initiative received crucial financial backing from the State Wetland Authority Kerala (SWAK).
Maneeja Murali, Senior Programme Officer at ATREE-CERC, noted that adverse weather conditions, including rain and prevalent slush, hindered the counting efforts. However, the data clearly indicates a decline when compared to the 17th VFC, which recorded a healthier 85 species (74 finfish and 11 shellfish).
A Growing Cause for Concern
Among the most alarming findings is the continued shrinking of the giant freshwater prawn, known locally as Attu Konju (Macrobrachium rosenbergii). Its average weight has plummeted from 500-600 grams to approximately 300 grams. This consistent decline in both the availability and size of these prawns over three consecutive years underscores a critical need for immediate conservation efforts, as emphasized by Ms. Murali.
Further research into the struggles of the giant freshwater prawn and the broader reduction in fish diversity across the lake is strongly advocated by Sajeevan M. K., Dean of the Kerala University of Fisheries and Ocean Studies (KUFOS).
Widespread Environmental Degradation
Volunteers reported significant environmental issues impacting fish populations. Dense blankets of water hyacinth made many areas inaccessible by boat, directly affecting the survey’s reach and the natural habitat. Near the Nazarath church at Kumarakom, oil deposits were observed spreading across the water, severely limiting fish presence. Furthermore, decaying organic matter was found in numerous locations, contributing to poor water quality. Pathiramanal island also showed substantial accumulation of plastic waste, further degrading fish habitats.
The two-day event commenced with an orientation program on September 25, followed by the dawn fish count on September 26, with participants divided into three groups. The concluding ceremony, held at Thanneermukkom, was inaugurated by Priyadarsanan Dharma Rajan, a senior fellow at ATREE.