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Floodplain wetlands are among the most threatened ecosystems. It is highly vulnerable to climate change, affecting the wetland ecosystem and its associated fisheries. In the face of data deficiency, this article presents an alternative approach to assess the vulnerability of wetland fisheries to climate change. A total of 15 wetlands from a wetland-fisheries-rich area of West Bengal, India, were selected to illustrate the methodology. The proposed method mainly relies on stakeholders' perceptions of the wetland fisheries vulnerability. Elicitation stakeholders' response iteratively screened the indicators of fisheries vulnerability. The hybrid method of index-based vulnerability comprises two types of indicators: climate indicators with long-term quantitative data and stakeholder perceived vulnerability indicators specific to wetland fisheries. The high level of consensus (92%) among respondents provided strong evidence of climate change in last 15 years, which has also been validated through long-term data analysis. The Principal Component Analysis extracted five synthesized vulnerability indicators, explaining 83.35% variability of the original 14 indicators. The wetlands were further grouped according to differential vulnerability for prioritizing the wetlands for strategic planning. Climate change, reduction in species richness and adaptive capacity were the key components responsible for differential vulnerability. The study also revealed some indigenous climate-smart mitigation strategies of wetland fisheries to climate change. [ABSTRACT FROM AUTHOR]

The small-scale fisheries sector plays very significant role in Indian fisheries. Fish life history parameters such as growth and morality are considered important factors for their conservation and management. Accordingly, the population parameters of a commercially important freshwater clupeid fish, Gudusia chapra (Hamilton, 1822) of Mathura beel, a tropical oxbow lake in West Bengal were investigated on the basis of primary data using a FiSAT-II software package. A total of 2062 specimens of both sexes combined, exhibiting a length (TL) range 1.7-15.4 cm and a weight range of 1.14-35.69 g, were collected from different sites of the wetland during October 2017-September 2019. The growth parameters L∞, K and t0 of the species were 16.55 cm, 1.10/year and -0.02, respectively. The growth performance (ϕ) was 2.48. The estimated mortality rates Z, M and F were 2.72, 1.25 and 1.47/year, respectively. The current exploitation ratio (E) was estimated to be 0.54 based on the length-converted catch curve. Analysis of the relative yield per recruit and relative biomass per recruit model indicated that the current E value is approaching an Emax value of 0.56. The maximum sustainable yield of this species was estimated to be 10.7 t, compared to the present annual yield of 11.5 t. For optimal fisheries management and a reduced risk of over exploitation, the current exploitation rate should be reduced by about 40% to achieve E0.5 as a target reference point. The information generated in the present study will facilitate optimal management of the resources for sustainable fisheries management and conservation of G. chapra. [ABSTRACT FROM AUTHOR]

Wetlands are among the most productive of all aquatic ecosystems. In developing countries, millions of marginal fishers rely solely on wetlands for security of both nutrition and livelihood. The decline in wetland fisheries owing to anthropogenic and climatic changes has made fishers increasingly vulnerable. Pen culture can be an effective climate-resilient technology for enhancing fish production in shallow, macrophyte-choked, and multi-stake floodplain wetlands, especially in eastern and north-eastern India. In this context, pen culture was implemented as an adaptive measure in a tropical Gangetic wetland (Mathura) to enhance fish production and increase the adaptive capacity of fishers. Indian Major Carps, Gibelion catla, Labeo rohita, and Cirrhinus mrigala of initial size 10.4±.21g, 8.2±0.48g, and 6.5±0.23g respectively, were stocked at the ratio of 4:4:2 and at the rate of 30 fish m-2 each in pens of 100 m2 in duplicate. For purposes of conservation, Labeo bata and Gudusia chapra, 4.3±0.18g and 3.8±.34g initial size, respectively, were stocked at the rate of 20 Nos.m-2 each at the ratio of 1:1. The fish were fed with commercial feed at the rate of 4% of body weight. A net survival of 82%, 87%, and 75% was recorded in Indian Major Carps, L. bata and G. chapra. A production of 380 kg IMC was achieved during 120 days of the culture period. L. bata achieved an average weight of 21.40±0.34g during the 90-day culture period, with a survival rate of 87%. G. chapra attained an average weight of 16.5±0.42g during the culture period, with a recorded survival rate of 75%. G. chapra was observed to spawn in the pen. The water quality inside pens and reference sites did not differ significantly (p>0.05). The produced fish were released in the wetland for fisheries enhancement. The present communication discusses the technological suitability and economic feasibility of adopting climate-resilient pen culture as an adaptation measure for enhancing the adaptive capacity of wetland fishers in the face of a changing climate. [ABSTRACT FROM AUTHOR]