The world’s fish populations are already being affected by global warming, and the human population faces long-term consequences with respect to seafood supplies and local economies that depend on them, according to a statement from the United Nations Food and Agriculture Organization.
These conclusions are coming out of a four-day conference of 200 experts and policymakers focused on the marine fisheries issue. The conference, in Rome, Italy, comes to a close today.
Changes already being seen, as reported in a technical summary (PDF 160 kb) written prior to the conference:
- Oceans are warming, while currents, such as those affected by El Nino, seem to be changing. This could have implications for the West Coast.
- Salinity is changing in surface waters, with warming areas of Earth growing more salty from evaporation, while more northern and southern areas grow less salty from increased rain along with ice and snow melt.
- Global sea level has been rising since 1961 with an accelerated rate since 1993.
- Fish distribution has been changing, generally with both warm- and cold-water species moving closer to the poles.
Predictions for the future:
- Changes in fish availability will change at the local and regional levels.
- Markets for various seafoods could grow unstable, as distribution systems try to respond to shifts in supply at various locations.
- Prices for various seafoods could fluctuate with uncertain supplies, and those in the industry could see their jobs disrupted.
- Countries where people eat a lot of seafood may face changes in nutrition with related health implications.
The technical summary also includes this statement:
At both the local and global levels, fisheries and aquaculture play important roles in providing food and generating income. Some 42 million people work directly in the sector, the great majority in developing countries. Adding those who work in associated processing, marketing, distribution and supply industries, the sector supports several hundred million livelihoods.
Aquatic foods have high nutritional quality, contributing 20 percent or more of average per capita animal protein intake for more than 2.8 billion people, again mostly in developing countries.
Fish is also the world’s most widely traded foodstuff and a key source of export earnings for many poorer countries. The sector has particular significance for small island states.
Another reality with climate change and we’re seeing the tip of the ice burg already, is ocean acidification; this will have huge influence on many marine plants and animals, including those needing to grow calcium-based shells, like clams and oysters. As oceans warm there’s also strong likelihood of broader distribution of predators, pests, and disease organisms that are non-indigenous.