The Lake Victoria Basin already supports a rapidly growing population—currently 30 million—which will further pollute the waters, said John Balirwa, director of the Ugandan Fisheries Resources Research Institute.
"Here on the island, perch sells for 2,000 shillings a kilo [2.2 pounds]," or about U.S. $1.15, said Charles Lubulwa, a middleman who sells to fish-processing plants on the mainland.
"That same perch goes for 2,500 [shillings] in Kampala and for nearly 4,000 once it's cleaned and shipped to Europe or Korea. With prices like that there will always be more fishermen."
A Boom Too Big?
Villages like the one on Nsazi are magnets for Uganda's unemployed.
"There are 2,000 people in this village," said Geoffrey Kimenke, who owns the hamlet's lone video hall, where patrons pay to watch Nigerian martial arts films on a generator-powered television.
"There were 600 when I first came here in 1998."
The village is a collection of mud and woven-branch huts separated by muddy lanes, with a few houses built of wooden plank and even fewer sitting on concrete foundations.
Water is fetched from the lake, and a stand of trees serves as the community latrine.
"We have four clinics, but the health situation is not good—a lot of diseases. ," Kimenke said.
"It's the water—there's no sanitation."
The Lake Victoria fishing industry employs more than 200,000 people in Uganda and hundreds of thousands more in Kenya and Tanzania.
The export business has spawned modern processing plants, trucking companies, and air-cargo brokers.
It has also brought fleabag hotels, restaurants, prostitution, and bars. According to one recent study, Uganda's breweries and soda distributors are among the biggest domestic beneficiaries.
At barely 10,000 years old, Victoria is a young lake.
Until the 1950s its native species were too meager to support a large-scale fishing industry. In that decade British colonial administrators seeded the lake with Nile perch from Lake Albert, located on the border of Uganda and the Democratic Republic of the Congo.
In time the perch conquered Lake Victoria, devouring hundreds of native fish species.
Nile perch can grow to more than 5 feet (150 centimeters) long and weigh as much as 400 pounds (180 kilograms).
Their prolific excrement helps feed another invasive species, the water hyacinth, a fast-growing weed that is choking the region's waterways.
Foreign demand, however, has priced the Nile perch out of local budgets.
As the cost has quadrupled over the last decade, the amount of fish protein consumed by Ugandans each year has fallen from 22 pounds (10 kilograms) per capita to 4.5 pounds (2 kilograms) today, according to the Uganda Fisheries Resource Research Institute.
City dwellers have shifted to fish that are less appealing to European customers. Rural areas, though, have seen a sharp decline in their overall protein intake.
Some families have resorted to eating fish "frames," the deep-fried fish heads and skeletons that are resold to local middlemen after fillets are frozen and shipped abroad, said Godwin Khisa, an economic analyst at Uganda's National Agricultural Research Organization.
Smaller Each Time
Cutting through 5-foot (150-centimeter) swells in Lake Victoria, a fisher named Frank piloted a leaky, unpainted 22-foot (6.7-meter) boat southwest of Nsazi island.
After two hours he and his assistant fed hundreds of yards of netting into the water, the nets' bottoms weighted by tiny bags of gravel, the tops suspended by chunks of cork.
Six hours later the two fishers took turns hauling up the catch. Soon the first perch appeared, stiff and dead, its open mouth revealing a swollen protruding tongue.
For two more hours they pulled up the nets, piling more than two dozen perch onto the floor of the boat, most of them smaller than the legal minimum of 18 inches (45 centimeters).
A few catfish came up and were thrown into a separate pile for the local market.
By now it was dark, and the crew headed home, arriving 11 hours after they had left.
"It's a good catch, yes," Frank said, as the fish were weighed at a scale by the shoreline.
"It's just smaller each time."
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