Thus the far published data on Ashtamudi fish diversity includes 156 species, where else  Ashtamudi Fish Census (AFC) 2022 recorded and collected 51 species. The finalized list may enhance the number of species, as the results of the market survey are being analyzed. One of the salient features of AFC is the decline in species diversity, and increase in the predominance of marine species, even in the freshwater zone, which indicate a decline in the freshwater flow from the Kallada river. The team also recorded two species for the first time from the lake, which included the tripod fish Tricanthus bicaculeatus (local name Muppiri), and Queenfish, Scomberoides lysan (Cheru paara).

The market survey showed the trends in the dominance of mackerel (Ayala) and Trachinotes blochii (Valavode), in the lake, indicating the increasing presence of marine fish in the lake, which could be an interesting aspect to study in relation with the climate change of the oceans. The team recorded decline in the mean size of the commercially valuable fish, including pearl sport (Karimeen) and mud crab (Kaayal Njandu).

Fish diversity was found to be less in polluted zones of the river, indicating the threats of pollution in the system. Urban pollution, solid waste (specifically plastic pollution) have grown significantly in the region, impacting biodiversity. Of late, there is also rapid invasion by the alien Mytella strigata (Charu Mussel) in Ashtamudi Lake, with significant impacts on native populations of Perna viridis (Green mussel) and the dominant clam species, besides impacting the fish breeding sites in the region.

The other threats to the fish diversity recorded from the region include electric fishing, illegal fishing using small-mesh size nets and poison, and siltation are the other threats in the region.

The team forwarded the following suggestions to better manage the rich fish diversity and biodiversity-dependent livelihoods.

1. Regulations to manage the number of Chinese fishing nets and stake nets in the region based on the carrying capacity of the system and population of commercial fishes.

2. Impose minimum legal size restrictions for all commercial species fished from the lake.

3. Publish a comprehensive publication on the fish diversity of the lake and organize regular education and awareness programs highlighting the unique biodiversity of Ashtamudi lake.

4. Considering the increasing encroachments of the watersheds of the lake, the district authorities should prepare spatial planning in the lake and its watershed.

5. Arrange regular desilting of the estuaries and remove dredged deposits scientifically.

6. Considering the survey report that the mangrove areas act as the rich breeding grounds of fish, crabs, and shrimps, launch a mangrove restoration and livelihood enhancement program coupled with responsible tourism, with the help of fisher’s cooperatives and women self-help groups, and community participation.

7. Ashtamudi lake is the only lake in India that supports locally valuable Arrowfin goby (Oxyurichthys tentacularis) (local name: Koozhavali), declare a fish sanctuary in Ashtamudi lake, after conducting a detailed study on its population dynamics.