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This paper reviews the past and present conditions and management of Chilika Lagoon, the largest lagoon on India's eastern coast. Spatial and temporal salinity gradients, because of freshwater river inflow and seasonal seawater influx, have created unique characteristics of an estuarine ecosystem, and exercised a continuous, selective influence on the biota. Unfortunately, its biodiversity and the livelihoods that depend on it were being lost at a fast rate because of a blockage of the lagoon's mouth by silt coming from upstream catchments, as well as oceanic long-shore transport. Projects to restore the dynamic characteristics of the lagoon included dredging a new mouth to the ocean, as well as prevention of soil erosion in upstream areas. Management efforts resulted in a dramatic revival of this ecosystem, and contributed to a sharp rise in the incomes of fisherfolk. The institutional aspects of implementing such large-scale policy changes also are discussed, and the remaining issues and lessons learned are presented.

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The wise use of wetlands is expected to contribute to ecological integrity, as well as to secure livelihoods, especially of communities dependent on their ecosystem services for sustenance. This paper provides a conceptual framework capable of examining the goals of wetland management, poverty reduction and sustainable livelihoods. The framework highlights ecological character as a social construct and, with the notion of wetlands as settings for human well-being, builds a concept for assessing the inter-linkages between ecosystem services and livelihoods. The value and broader applicability of our framework is then tested by applying it to a case study from India (Lake Chilika) to evaluate the degree to which the mutual goals of improving both human well-being and the ecological character of wetlands have been achieved. The case study maps changes in human well-being induced in the basin communities due to external vulnerability contexts, institutions and freedoms. It further assesses the response strategies in terms of their impacts on ecological character and poverty status.Key words livelihoods; biodiversity; development; Ramsar Convention; wetlands; ecosystem services; poverty; Chilika Lake Evaluation des liens entre services écosystémiques des zones humides et pauvreté: cadre général et étude de cas Résumé L'utilisation rationnelle des zones humides est censée contribuer à l'intégrité écologique, ainsi qu'à assurer les moyens de subsistance, en particulier des collectivités tributaires de leurs services écosystémiques pour la nourriture et les ressources de base. Cet article fournit un cadre conceptuel capable d'examiner les objectifs de gestion des zones humides, la réduction de la pauvreté et les moyens de subsistance durables. Le cadre souligne le caractère écologique comme une construction sociale et, avec la notion de zones humides comme cadre pour le bien-être humain, construit un concept pour l'évaluation des liens entre les services écosystémiques et les moyens de subsistance. La valeur et l'applicabilité plus large de notre cadre sont ensuite testées en l'appliquant à une étude de cas en Inde (Lac Chilika) pour évaluer à quel niveau les objectifs communs d'amélioration à la fois du bien-être humain et du caractère écologique des zones humides ont été atteints. L'étude de cas dresse la carte des changements dans le bien-être humain, induits, dans les communautés du bassin, par des contextes de vulnérabilité externe, les institutions et les libertés. Il évalue ensuite les stratégies de réponse en termes de leurs impacts sur le caractère écologique et le niveau de pauvreté.

Chilika Lake, an assemblage of marine, brackish and freshwater ecosystems, on the east coast of India is a designated Ramsar site and a biodiversity hotspot. Intensive ichthyofaunal inventories and biodiversity assessments were carried out during 2000–2014 and documented 317 species belonging to 207 genera, in 88 families and 23 orders, including two endemic (Gobiidae) and one exotic cichlid species (Oreochromis mossambicus). In total, 255 collections (178 collections of previously recorded species and 77 that represent newly recorded species) were made during a post-restoration survey accounting for 80.44% retrieval of historically documented species. This paper presents an updated and comprehensive checklist of the lake’s ichthyofauna (1916–2014), which is comprised of 278 food fishes, 271 (85.49%) migratory and 46 (14.51%) are resident species indicating that the lake fishery is largely migratory species-dependent. An account of faunal characteristics for 129 commercially important species is provided. The checklist also documents 48 threatened species and 103 species under different categories of conservation status.

The growth, mortality and stock status of grey mullets Chelon parsia (Ham. 1822), Chelon planiceps (Val. 1836) and Mugil cephalus (Linn. 1758) were investigated during December 2010 to November 2011 from Chilika Lake, Asia, largest brackish water lake. The length‐based analysis, using length frequency data collected from fish landing centres, formed the basic study methodology. Growth function and population parameters were studied using FAO‐ICLARM Stock Assessment Tools‐II (FiSAT‐II). The von Bertalanffy growth function (VBGF) was established as Lt = 321 mm*(1 − exp (‐0.98 year−1 × (t + 0.085 year)) for C. parsia, Lt = 315 mm × (1 − exp (−0.80 year−1 × (t + 0.105 year)) for C. planiceps and Lt = 700 mm*(1 − exp (−0.70 year−1*(t + 0.097 year)) for M. cephalus. Lower K and higher L∞ values for M. cephalus indicated slow growth and high longevity of the species, compared to other grey mullets. Length–weight relationships were derived, indicating isometric growth for grey mullets. Recruitment of mullets was observed throughout the year, with a peak during April–July. About 50% of the mullets were caught by fishing gear before reaching their first year of age. The level of exploitation (E ≥ 0.60) was more than the optimum level (E = 0.4 for pelagic stock), indicating overexploitation of grey mullets in Chilika Lake. Moreover, the average annual yields of three mullets were observed to be higher than the estimated maximum sustainable yields (MSY), also indicating overharvesting of mullets. Thus, the mullets could be considered one of the highly overexploited resources in Chilika Lake. The findings of this study will facilitate the development of appropriate management strategies for the mullet fishery in Chilika Lake.