Vulnerability of aquaculture-based fish production systems to the impacts of climate change: insights from inland waters in Bangladesh

Abstract

Aquaculture plays a vital role in the agro-based economy of Bangladesh through its contributions to employment and income generation, and through provision of food and nutrition for the people of the country. In addition to 1.32 million full-time fisherfolk, 14.7 million people are involved in aquaculture in Bangladesh. Though all of Bangladesh is more or less prone to adverse impacts of climate change, the northern and northwestern drought-prone areas and coastal regions are particularly sensitive because of specific hydrometeorological, climatic, and human-induced hazards. Erratic rain, irregular rainfall, and temperature changes affect the readiness of fish for breeding. In 2009–2010, extreme weather caused late maturity of fish for breeding in the Mymensingh region—the largest aquaculture zone in the country. Fish farmers are struggling with higher production costs due to water scarcity, higher and lower temperatures, day–night temperature fluctuations, and lower productivity of ponds. Hatchery production has also declined because of such causes. The Bangladesh Climate Change Strategy and Action Plan have considered the fisheries sector as one of the potentially most threatened areas to be targeted. The fisheries sector differs from mainstream agriculture and has distinct interactions and needs with respect to climate change. Capture fisheries have unique features of natural resource harvesting linked with ecosystem production processes. Aquaculture complements and increasingly adds to the supply and, though it is more similar to agriculture in its interactions, it has important links with capture fisheries. Most indigenous fish are migratory and rely on seasonal flooding for spawning cues and access to larval rearing habitats (floodplains). Habitat destruction also has a significant impact, as does lack of flooding/rain—an obvious impact of climate change in the last few decades. Since the economic impacts of climate change will have to be borne by individuals, communities, and the government, there is a need to evolve a climate-resilient development strategy involving all of the relevant sectors, including aquaculture. Only eco-friendly, improved, and innovative management practices with insights into technological, environmental, and socioeconomic concerns can mitigate the impact of climate change on aquaculture in Bangladesh and ensure sustainable fish diversity and production.