Strangling Africa’s Regal Lake

Musa Aloo, a fisherman for more than 50 years, woke one morning last October to find his job had vanished. That’s because his nets and boat, which he had left in the waters of Lake Victoria, were suddenly engulfed in a sea of vegetation.

A carpet of water hyacinth had drifted shoreward, blocking all movement to and from the lake’s edge for miles. Scores of fishermen, their boats similarly swallowed up, struggled in vain for days to remove the insidious, floating weed. But the faster the men pulled out the heavy, matted clumps of green, the faster they reappeared.

Aloo’s boat and nets eventually disappeared into the lake, robbing him of his only means of support.

“The water hyacinth has completely ruined my life, and I can’t do anything about it,” said Aloo, 66, whose catch of Nile perch and tilapia often fetched him more than $500 a month--respectable money in a country where the official average monthly wage is less than $100. “Now I depend on the goodwill of my friends, who try to support me. But I’ve been reduced to a beggar.”

The vegetation is choking Lake Victoria, the 26,828-square-mile body of water bounded by Kenya, Uganda and Tanzania. The fast-growing water hyacinth is threatening food supplies, trade, transportation and hydroelectricity for millions of lakeside residents.

Because the governments of the three East African nations bordering the lake aren’t cooperating in dealing with the problem, there is a dearth of reliable information about the severity of the infestation by the water hyacinth.

But some researchers believe that unless decisive measures are taken to eradicate Eichhornia crassipes, which has found especially favorable conditions in the nutrient-rich pollutants of the lake, the weed could suffocate the shoreline of the world’s second-largest body of fresh water in the next few years.

“You cannot underestimate it,” said Andrew Mailu, deputy director of the Kenya Agricultural Research Institute in the capital, Nairobi. The institute has been awarded $2.4 million by the World Bank to help develop a solution to the botanical plague. “It is a very serious concern,” Mailu added.

The water hyacinth, a South American native spotted in Kenya as early as the 1950s, was first sighted on Lake Victoria, a source of the Nile River, in 1990.

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Considered by many to be a beautiful and exotic species, the plant has been used as an ornamental decoration in other countries. It may have been brought to the Lake Victoria area by beachfront hotels, which used it for decoration, or it may have come aboard cargo-bearing ships trafficking on the lake waters.

But lakeside dwellers in Kenya quickly learned to be frightened by its overwhelming presence, swift movement when blown by the wind and amazing ability to double its size and volume every five to 15 days. Further, as they have learned, the plant thrives in polluted water, has a huge seed capacity and can survive for up to 20 years.

The pesky plant has created big problems in other places, from Florida, which has waged one of the longer and more successful wars against it, to Peru.

Kenyan officials say that although they have the smallest share of Lake Victoria--6%, compared with Uganda’s 43% and Tanzania’s 51%--their nation has been Africa’s most afflicted. More than 1% of Kenya’s lake waters already are said to be covered by the water hyacinth, and researchers say the rest could be swallowed up within five years.

The creeping menace has also captured part of the Kenyan capital: Water hyacinth swarmed over the lake formed by the small Nairobi Dam in just three months, cutting off swimming and even halting the baptisms that once took place. There are fears that the plant might sweep into the city’s water and sewer system.

Devastating Effect

The hyacinth’s socioeconomic effect has been devastating: It has so clogged several major ports that they have been closed; Kenyan officials estimate that a quarter of Lake Victoria’s trade and transportation has been curtailed.

Mathias Wafula, assistant director of fisheries in Kisumu, said the amount of fish caught in Kenya’s Lake Victoria waters dropped by more than 16,500 tons between 1995 and 1996. He estimates that the catch will decline by a further 55,000 tons by the end of this year. This, in turn, has caused fish prices to skyrocket.

The hyacinth mess “is hitting fishermen really hard,” Wafula said. “They just can’t fish. This is something they would never have imagined in their lives.”

In lakeside communities from Kisumu (pop. 700,000) to Homa Bay--62 miles to the southwest--tens of thousands of fishermen who once thrived on the aquatic bounty of Lake Victoria have been forced to find other, less lucrative jobs.

Meantime, lacking jobs or the earnings they once had, many parents have been forced to pull their children from school.

Elisha Ogonda Midega--who lives in Kusa, a village 25 miles south of Kisumu on the shores of Nyakach Bay--had to yank his three children from a private boarding school and put them into lesser classes nearby after his business collapsed: All four of his boats are now rotting in a water hyacinth field that stretches almost two miles to the horizon.

Here, what had been lake is now dry land; in just three years, the hyacinth not only destroyed his livelihood, it also sucked up all the water in part of a Lake Victoria bay.

The Murky Waters

On the beaches at Kusa, where 400 fishermen once moored boats, a handful of farmers grow yams, tomatoes, cabbage and rice. There are some determined anglers left. But they must travel to nearby beaches and rivers, where they catch the lungfish that thrive in the murky waters beneath the hyacinth.

“In a matter of years, instead of talking about this thing, we’ll be talking about the number of deaths because of it,” said Ogonda Midega, who also chairs a local environmental group and now lives by growing rice and rearing cattle.

Researchers at Osienala, a Kisumu-based environmental restoration group, say the hyacinth promotes the spread of diseases such as dysentery, which incubates in stagnant, dirty water; malaria, which thrives when mosquitoes burgeon in still waters; and bilharzia, which can be traced to snails that breed in the plant.

Experts at the Kenyan agricultural institute, while downplaying links between hyacinth and the spread of disease, do acknowledge that the plant blocks vital sunlight for underwater organisms and slashes the breeding space that fish need in shallow waters, causing a reduction in certain species.

Still, these researchers say the water hyacinth has not yet created a national disaster. “That’s alarmist,” said Stephen Njoka, director at the National Fibre Research Center on the outskirts of Kisumu. “It is not at that level of emergency.”

But critics say the Kenyan government has been too lax in grappling with the hyacinth problem.

“It is a crisis, and it’s becoming a disaster,” said Luis Navarro, senior program specialist at the International Development Research Center, a Nairobi-based Canadian institute that is trying to create an information clearinghouse for the water hyacinth. “But there is still no coordinated effort to do anything about it.”

American officials, particularly in Florida, have used combinations of chemicals and natural predator programs, and have pushed to curtail outside nutrient supplies to combat water hyacinth infestations. Here, the Kenyan agricultural institute has focused on importing and raising beetles from as far as Benin and Australia. These insects, in one phase of their life, feed voraciously on the hyacinth and thus are its natural enemy.

Researchers have spotted signs at the five sites where beetle eggs were released that the insects have devoured patches of water hyacinth. But the experts say it will take three to five years for the bugs to reproduce enough to significantly reduce the botanical infestation.

Weed removal by manual and mechanical means has proved to be a costly, time-consuming, short-term remedy; the use of chemicals has been ruled out by the three East African nations because of the possibly dangerous side effects on human and marine life.

Last year, at Dunga beach, Kisumu’s largest, authorities tried using a small harvester-type boat to dislodge the weed. Their efforts failed. The hyacinth had clogged the shoreline and extended more than a mile into the deeper waters of the lake, entangling nets, stranding boats and paralyzing all movement to and from the beach. Three people drowned after their boat capsized and rescuers could not reach them.

When officials failed to return with a bigger, better vessel, the fishermen of Dunga declared their own war on the water hyacinth. They had seen their catch drop by half within a 10-month period and membership in their cooperative fall from 131 to 78.

Weed-Busting Gangs

So they organized weed-busting gangs and spent days pulling up the aquatic plants by hand. The vegetation was later burned in heaps on the sand.

But Dunga fishermen fear they have not seen the last of what they call the “green plague.”

“It could float back any time now and cause the same problems again,” said John Otieno, a fisherman for 30 years who depends on his catch to support his eight children. “This concerns me.”

The worries about this plant’s aggressiveness, its persistence and the pervasive misinformation about it have helped fuel conspiracy theories.

Some lakeside residents believe the hyacinth invasion is part of an American plot, supported by the Kenyan government, to help exterminate Nyanza province’s predominantly Luo community. The Luo have traditionally been in the political opposition, and many feel their towns and villages have been intentionally neglected by the Kenyan authorities.

Others believe that Uganda--with which Kenyan relations have soured over the years--maliciously planted the weed in Kenyan waters, having itself been defeated by the hyacinth.

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Still others insist that the sudden spread of the plant is the result of a scientific blunder. “We’d never heard of it,” said Peter Oman, chairman of the Kichinjio beach fishermen’s cooperative. “We don’t know where it came from. We just can’t figure it out.”

Osienala, the environmental group, has started a campaign to educate Kenyans about the water hyacinth. “It’s there now, so people must learn to live with it,” said Kinya Munyirwa, the group’s programs officer.

The experts, for example, are encouraging fishermen to retake tiny sections of the lake at a time--to enclose small areas with their nets, pull up the weed and then catch the fish that reappear.

Meanwhile, in Homa Bay, a group called South Nyanza Future in Our Hands is teaching women to weave baskets and make handicrafts from dried water hyacinth.

The group, backed by private money and Swedish development aid, also hopes to persuade Kenyans to use the plant to plug gullies and ravines and as a barrier to protect crops. “Everyone thinks it is just a dangerous weed, but we think it has certain assets,” said Werne Bauer, one of the South Nyanza group’s project managers.

But most locals remain unconvinced. “We see it as a nuisance,” said Munyirwa. “It is something that has made us poorer. It has made the lake, which was thriving with activity, a dead lake.”