Catch of the Day: The State of Global Fisheries Part Six, Issue 23 Catch of the Day: The State of Global Fisheries

Objectives After reading the assigned chapter and reviewing the materials presented the students will be able to understand: What are the environmental impacts of commercial fishing? Do sustainable fisheries exist? Is aquaculture sustainable?

Report Cites Dire Condition of Europe’s Fisheries More than 40 percent of commercial fish species in the northeast Atlantic and adjacent seas are being caught at higher than sustainable rates. The European Union proposed major fishing cuts: reduction of up to 60% in herring catches, 34% for cod, and 27% for mackerel. The proposal was a balance between what was biologically necessary and what was economically reasonable.

The Importance of Global Fisheries The value of international fish trade for 2004 was $71 billion. U.S. fishery product exports to China in 2005 were $356 million representing 11.8% of China’s seafood imports. Canned fishery products worth $1.1 billion were produced in the United States in 2005. Processed fishery products in the United States were valued at $6.6 billion as of 2004. The economies of many countries such as Iceland, Peru, and Norway depend heavily on fish product exports. In eastern Canada, the closure of the cod fishery cost at least 40,000 jobs in a country with a population one-tenth that of the United States.

Are We Running Out of Fish? Humans obtain fish and shellfish in three ways: marine capture fisheries, fresh water capture fisheries, and aquaculture or fish farms. According to the Food and Agriculture organization (FAO) of the UN for 47% of the species we have reached or are very close to the maximum sustainable limits. Another 16% like Atlantic cod are overexploited. Another 10% have already been significantly depleted. Chinese production has continued to increase. The top capture fisheries nations are China, Peru, United States, Indonesia, Japan, Chile, and India. According to the Worldwatch Institute, industrial fleets fished out at least 90% of all ocean predatory fish – tuna, marlin, swordfish, sharks, cod, halibut, skates, and flounder.

Environmental Costs of Fishing In trawling, done for bottom associated species like shrimp and Atlantic cod, a 10 to 130 meter (33 – 426 ft) net is scraped along large areas of the bottom, collecting everything in its path. Saturating trawling has been compared to clear cutting a forest. Extremely destructive methods like dynamiting and poisoning are still used in some areas. Habitat loss, including mangrove destruction from shrimp farming, is one impact of aquaculture. In Ecuador alone over 200,000 hectares (approximately 500,000 acres) of mangrove ecosystems and adjacent landscape have been converted to shrimp agriculture.

The Slimehead and the Patagonian Toothfish Marketing specialists renamed them orange roughy and chilean sea bass. The orange roughy fishery began off New Zealand in 1978 and quickly exceeded 35,000 tons. Maximum sustainable yield is 7,500 tons. Chilean seabass is also vunerable to overfishing (www.blueocean.org).

Aquaculture Two-thirds of aquaculture takes place in inland rivers, lakes, ponds, and artificial tanks. Coastal marine aquaculture (mariculture), which includes estuaries and coastal ocean, accounts for the remainder. The Chinese mainly raise herbivorous species like carp. By contrast, other countries (Norway, Chile, Britain, Canada, and US) raise carnivorous species like salmon. Carnivorous species put additional stress on wild fish stocks, since up to 5 kilograms of wild caught fish (in the form of pellets) must be fed to salmon to produce one kilogram of meat.

Aquaculture In Norwegian salmon farms, the fish produce as much waste as Norway’s 4 million humans. Many farm raised salmons are fed large doses of antibiotics. Areas devoted to shrimp farms tend to be cleared mangrove swamps. Mangroves are of critical importance as nurseries for juvenile fish and other marine animals. Coastal areas in Sri Lanka where mangroves were cleared were devastated by the 2004 tsunami.

Advantages of Fish Farming According to Lester Brown, the President of the Earth Policy Institute: Cattle require 7 kilograms (kg) of grain to add 1 kg of live weight, whereas fish can add a kg of live weight with less than 2 kg of grain. It takes 1000 tons of water to produce 1 ton of grain. Efficiency of fish farming of grain turns into an advantage of water efficiency as well.

Summary The Importance of Global Fisheries: Processed fishery products in the United States were valued at $6.6 billion as of 2004. The economies of many countries such as Iceland, Peru, and Norway depend heavily on fish product exports. Humans obtain fish and shellfish in three ways: marine capture fisheries, fresh water capture fisheries, and aquaculture or fish farms. According to the Worldwatch Institute, industrial fleets fished out at least 90% of all ocean predatory fish – tuna, marlin, swordfish, sharks, cod, halibut, skates, and flounder. Saturating trawling has been compared to clear cutting a forest. Extremely destructive methods like dynamiting and poisoning are still used in some areas. Habitat loss, including mangrove destruction from shrimp farming, is one impact of aquaculture. Two-thirds of aquaculture takes place in inland rivers, lakes, ponds, and artificial tanks. Coastal marine aquaculture (mariculture), which includes estuaries and coastal ocean, accounts for the remainder. Advantages of Fish Farming: Cattle require 7 kilograms (kg) of grain to add 1 kg of live weight, whereas fish can add 1 kg of live weight with less than 2 kg of grain. It takes 1000 tons of water to produce 1 ton of grain. Efficiency of fish farming of grain turns into an advantage of water efficiency as well.

Home Work 1. What are the 3 ways in which humans obtain fish? 2. What are the advantages of fish farming?