According to the State Action Plan on Climate Change prepared by the Department of Environment and Climate Change, diseases and migration of species could lead to the depletion of fish stocks, while the damage or loss to coastal infrastructure could enhance the vulnerability of the fishing community. Changes in water temperature and variables such as sea level rise, wind velocity and wave action could trigger ecological and biological changes in marine and freshwater ecosystems, impacting on the distribution and abundance of fishes.

Inland fisheries

In the case of inland fisheries, the action plan assesses the risks posed by the depletion of inland water bodies, increased incidence of water-borne diseases among fishes and heavy deposit of silt during floods.

Pointing to the increase of 0.6 degrees centigrade in sea surface temperature over the past 50 years, it says the trend could affect the growth and life span of several species, especially of the pelagic group (dwelling neither close to the bottom nor near the shore).

The report notes that sardines and mackerels, which were abundantly available off the Kerala coast, had moved away to deeper waters in recent years.

Several important species of marine fish and high-value shrimp too had become rare while some traditional species in the Vembanad Lake had disappeared. At the same time, the report observed, puffer fish, seen as a menace by fishermen, had become abundant. The main shoreline change in many fishing villages has seen the virtual disappearance of beaches, it says.

Mangrove forests

The document estimates that the potential decline in mangrove forest habitat due to sea level rise, changes in sediments, pollutants from the rivers and lakes, sand-mining, deforestation, and massive reclamation of coastal wetlands could impact the coastal biodiversity. The clandestine introduction of exotic fishes into inland water bodies is another factor that is affecting the biodiversity of fish.

The lack of facilities for monitoring marine and estuarine pollution is cited as a severe shortcoming. The non-biodegradable pollutants have the potential to alter the aquatic ecosystem to a considerable extent, the report warns.

The action plan notes that climate change was threatening to play havoc with traditional fishing practices. Aberrant rains, changed wind patterns, storms, and changes in the marine ecological balance could affect the very survival of the fishing communities, it says.

Mitigation strategy

The plan outlines a mitigation strategy focussing on the establishment of fish sanctuaries for conservation of marine biodiversity, protected sanctuaries for aquaculture development in wetland zones and coastal afforestation to offset the impact of paddy field and wetland reclamation. It also recommends a campaign to create awareness about climate change impact among stakeholders.

The report moots steps to promote organic aquaculture and ensure sustainable inland fisheries through integration of fisheries, aquaculture and agriculture. It also stresses the need to strengthen information networking in the inland fisheries sector and create a system for prediction of production levels based on environment factors.

Vulnerability

Vulnerability assessment for the low coastal areas exposed to floods and salinity ingress is another major activity to be taken up.

The report calls for a sustainable livelihood approach to manage the likely impact of climate change on fishery production.

The recommendations will be taken up for implementation from the current year, according to officials at the department.