Effects of Global Warming on Fisheries
Global warming caused by the trapping in the atmosphere of gases (e.g., carbon dioxide, methane, etc.) produced by massive fossil-fuel burning industries has raised global temperature resulting to climate change and rising sea level.
Climate change is driving extreme climatic events such as droughts, severe cyclones, and floods. Rising sea level is expected to swamp low-lying areas of the country in the years to come especially with the melting of the polar glaciers.
According to the Intergovernmental Panel on Climate Change, East Asia is one of the most vulnerable regions facing widescale impact of the global warming phenomena.
In the fisheries sector where many coastal villages depend for livelihood, effects of global warming could displace thousands of families. Coral reefs are threatened because of carbon dioxide concentration resulting to acidification of seawater. An increase in sea surface temperature also causes bleaching in corals, and deleterious effects on reef accretion and biodiversity (McCathy et al., 2001).
To mitigate the impact of warming temperature on the fisheries sector and help the sector adapt to the changes, the Department of Science and Technology’s Philippine Council for Aquaculture and Marine Research and Development wants the public to keep tab on the following:
For inland fisheries (lakes, rivers and ponds)
- Lakes serve as catch basins for run-off from watersheds. Watersheds should be protected and conserved to ensure recharging of water lost through evaporation and filtration.
- Rivers may be heavily silted with severe flashfloods and mudslides brought by unusually heavy rainfall in affected areas.
- Fishponds in coastal areas are at risk to inundation with a rise in sea level. Increasing the height of dikes or installation of perimeter nets may also be considered.
- To conserve water and soil in the uplands and mitigate floods in the lowlands, small farm reservoirs or impoundments should be constructed. Such water bodies can also be used for production of fish, crops and livestock.
- Mangroves (“bakawan”) in coastal fringes will be inundated by rising sea level. There should be a “free zone” of at least 100 meters from the shoreline to allow mangrove species to expand inland.
- More Marine Protected Areas or MPAs should be established in critical areas where coral bleaching may occur due to increase in sea surface temperature. MPAs enhance recovery of affected areas and protect biodiversity.
- Cage or pen farming of fish and other cultured species could be a practical and profitable option in flood-prone areas.
- Promotion of seaweed farming in appropriate areas could reduce carbon dioxide concentration in seawater through photosynthesis. STP