Bangladesh is one of the most vulnerable nation to climate change because of its position. The fisheries and aquaculture industries are seriously concerned about climate change, especially as it relates to fish productivity. Fish and their habitats will be affected by climate change. Warmer temperatures will affect which species may be farmed in specific places as well as the abundance, migration patterns, and mortality rates of wild fish stocks. People who depend on fisheries and aquaculture, including employees, coastal communities, and fish eaters, will experience social and economic implications as a result of these climate effects on fish.
Impact on marine environment:
On our oceans and marine life, climate change is having a significant effect. Oceans have a significant impact on climate dynamics since they are the primary conduit for 83% of the global carbon cycle. Since the 1970s, they have absorbed 93% of the extra heat from greenhouse gas emissions.
Between 500,000 and 10 million marine species reside in the waters, which significantly adds to the richness of our world. The distribution of fish stocks and their diet is altering as a result of its consequences. Marine capture fisheries, which already struggle with a number of issues like overfishing, ocean acidification, coral bleaching, sea level rise, habitat degradation, and poor management, are not well-equipped to deal with new issues brought on by climate change.
Sea level rise and the salt of the soil and water have both good and harmful effects in coastal areas. The cultivation of shrimp and other brackish water fish and shellfish may increase as sea levels rise and soil-water salinity, which will boost the production of high-value fish items. But, it may decrease the production of freshwater species in these region. The Sundarban, the biggest mangrove forest in the world, is also impacted by climate change, which leads to the extinction of many marine fish species and the loss of their spawning grounds. Climate change may have an impact on marine fish species, pH changes, and temperature increases, as well as an increase in the frequency of intense tropical cyclones and surges in the Bay of Bengal.
Impact on Fisheries Sector:
Fishing communities are vulnerable, and storms and other extreme weather can jeopardize their livelihoods. Processes like changing river flows have a major impact on freshwater ecosystems and have clear effects on fishermen. Impacts on security, migration, transportation, and markets will also have an adverse impact on the social and economic backdrop of fishing. Fisheries are already changing quickly as a result of overfishing and globalization. They will experience a wide range of diverse effects from climate change, some of which may be unforeseen and shocking. The least fortunate will find it hardest to adjust to these effects.
Impact on Aquaculture Sector:
Fish hatcheries of Bangladesh are affected both directly and indirectly by climate change, notably at different stages of hatchery production and in terms of the financial loss brought on by the emergence of disease and other environmental-related impairments. Geographically, the majority of Bangladesh’s aquaculture farms are managed within a constrained range of temperature (22.8-23.1 °C, or 73-73.5 °F) and rainfall (1750-2000 mm). Thus, even the smallest changes in these factors have an impact on fish output.
The broodstock, raised in both natural and artificial environments, is adversely impacted by temperature changes, unpredictable rainfall, river siltation, flash flooding, and deteriorating water quality. Climate change related temperature variations impair the maturation and reproductive abilities of broodstock, have an impact on embryonic development, and result in stunted larval and juvenile growth. Post-larval disease epidemics are brought on by changes in temperature, pH, and salinity in shrimp and prawn hatcheries. Storms and torrential rains can sometimes sweep away farm-raised broodfish and fish seed, resulting in significant socioeconomic losses.
Farhana Islam
Agriculturist, Researcher
