Ecological sustainability assessment of the Netravathi–Gurupur estuarine ecosystem in south-west India:  Implications for fisheries management

Preetha  Panikkar; Feroz Khan M.; Sibina Mol S; Vijaykumar M. E.; Sonalika Sahoo; Ajoy Saha; Samanta S. K.; Das B. K.

doi:10.21077/

Authors

Preetha Panikkar ICAR- Central Inland Fisheries Research Institute
Feroz Khan M.
Sibina Mol S ICAR_Central Inland Fisheries Research Institute https://orcid.org/0000-0003-0804-6268
Vijaykumar M. E.
Sonalika Sahoo
Ajoy Saha
Samanta S. K.
Das B. K.

https://doi.org/10.21077/

Keywords:

ecology, food-web, model, Netravathi-Gurupur

Abstract

Tropical estuaries are dynamic, productive ecosystems with rich biodiversity, typically influenced by anthropogenic activities. The ecological integrity of the Netravathi Gurupur estuarine ecosystem in the south-western coast of India is under increasing pressure from habitat degradation and pollution. Given the estuary's significant economic importance coupled with scarce information regarding its ecological status and trophic interactions, an assessment of the ecological sustainability focusing on fish production was conducted using the Ecopath modeling approach. The model comprised 28 functional groups spanning primary producers (trophic level, TL 1.0) to top predators (TL 3.9), depicting a trophic structure predominantly regulated by bottom-up control. Most fish groups exhibited relatively low ecotrophic efficiencies (EE), suggesting limited exploitation pressure and substantial energy dissipation within the system. In contrast, crustaceans emerged as the most intensively exploited groups, with crabs (EE=0.952), shrimps and prawns (EE=0.819) approaching full utilisation, indicating strong fishing pressure at lower trophic levels. System-level indices indicated high total system throughput (22,655.12 t km^-² yr¹), reflecting high ecosystem productivity, but low ascendancy (38.33%), consistent with a developing ecosystem that retains resilience but remains sensitive to continued anthropogenic disturbances. These metrics provide a quantitative basis for evaluating ecological sustainability by identifying both vulnerable functional groups and critical trophic pathways requiring management attention. The findings facilitate ecosystem-based management recommendations, such as regulating crustacean harvests, protecting nursery habitats, and regulating pollutant inputs, thereby promoting sustainable resource use while maintaining ecosystem structure and services that support local fisheries and livelihoods.

Keywords: Ecology, Ecopath modeling, Ecotrophic efficiency, Fishing pressure, Food-web, , Trophic structure

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Author Biographies

Preetha Panikkar, ICAR- Central Inland Fisheries Research Institute

Principal Scientist, Regional Centre of ICAR- Central Inland Fisheries Research Institute, Hessaraghatta, Bangalore, India, 560089
Feroz Khan M.

Scientist (Rtd.), Regional Centre of ICAR- Central Inland Fisheries Research Institute, Hessaraghatta, Bangalore, India, 560089
Sibina Mol S, ICAR_Central Inland Fisheries Research Institute

Scientist

Reservoir and Wetland Fisheries Division
Sonalika Sahoo

Senior Scientist, Regional Centre of ICAR- Central Inland Fisheries Research Institute, Hessaraghatta, Bangalore, India, 560089
Ajoy Saha

Senior Scientist, ICAR- Central Inland Fisheries Research Institute, Barrackpore, Kolkata, India, 700120

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