Of the two hundred or so species swimming in the lake, the agent from the mainland is interested in just one. A strong, fast-swimming freshwater dweller that can grow to the size of a man, the Nile perch was venerated by the ancient Egyptians. The fish was associated with the goddess Neith, who had assumed piscine form while she and the ram-headed god Khnum-Ra came together to create the world. Two thousand miles north of here at Esna in Upper Egypt, there is a cemetery that houses nothing but Nile perch. Consumption of the fish was forbidden under the pharaohs, and when one died it would be embalmed with salted mud, wrapped in linen and placed in an individual grave (a preservation method so effective that specimens exhumed today can be eaten with no ill effects).

It was not until two thousand years after the death of the last pharaoh that the perch appeared for the first time at the great river’s source. After a long search, the British colonisers selected it as the species most likely to rescue Lake Victoria’s ailing fishing industry. Although it had proven commercially popular in other Central African lakes, their choice was controversial. By eating worthless cichlids, the perch would undoubtedly increase the fishery’s economic value. Because of its size, moreover – a mature adult can weigh two hundred kilograms – fishermen wouldn’t need to use nets with small holes to catch it, and the pressure on smaller species would be reduced. But introducing alien species carries risks, and ecologists worried that a new, large predator might further imperil the native fish, exacerbating the decline in the lake’s biodiversity. Many other environments around the world had been devastated by invasive species, and the effects on a complex ecosystem that had already shown signs of fragility were impossible to foretell.

The scientists lost the argument. The authorities decided that the perch’s success elsewhere was sufficient indication that it would cause no problems here, and the promise of immediate economic benefits rendered moot the ecologists’ concerns over a hypothetical future threat. In 1954, therefore, as the doom-mongers looked on helplessly, a colonial fisheries officer in Uganda picked up a bucket full of juvenile Nile perch, strode to the end of a wharf near Kampala, and emptied it into the lake.

For years nothing happened. Fish remained elusive, catch sizes continued to shrink, and the people of Ukerewe grew ever more desperate. In the past they could have turned to farming to feed themselves and their children, but this fallback was no longer available. The Bantu expansion had populated the southern half of Africa with farmers – four in five Tanzanians depend on agriculture for their subsistence. But on the islands of Ukerewe the expansion had reached its limit. Medical advances such as vaccination and the development of antibiotics meant that more children were surviving to adulthood and more adults to old age. The population mushroomed. To make room for and build new villages, ancient forests were cut down. Farmland, handed down through the generations, had to be divided into smaller and smaller plots if each child was to receive a fair share. To produce enough to feed a large family, it had to be exploited more intensively. Packing crops more densely facilitated the spread of pathogens, and ruinous diseases swept through banana plantations and cassava fields. Ukerewe had once been famed for the fertility of its land. Now the soil, overworked and with no trees left to protect it from the elements, was spent.

It would be twenty years before salvation arrived. The Nile perch had been slow to gain a foothold in the lake. It didn’t appear in catches until the late 1970s, long after the colonisers had departed. At first the islanders showed little interest in it. Compared with the fish they were used to it tasted bland, and it provided scant reward for the great effort required to ready it for eating. The lake’s native species could be preserved by being left to dry in the sun, but if you tried this with the oily perch it would rot. Before it could be cooked, moreover, the perch had to be filleted, and the Kerewe had no experience of filleting such a large fish. They remained indifferent even as it began to appear more and more frequently in nets. Most of the catch was left to decompose on the beaches.

Gradually, however, tastes changed. Government experts toured the islands, demonstrating how the new arrival, which came to be known in Swahili as sangara, should be smoked, sliced and cooked. With their cherished native species continuing to dwindle, the people of Ukerewe began to regard the perch as a palatable alternative. As a market for it developed, they also recognised its economic merits. The first catches of the fish in Tanzanian waters were not recorded until 1978, but subsequent growth was rapid. In 1981, Tanzanian fishermen netted one thousand tons of sangara. Five years later they landed eighty thousand tons. They sold their haul to businessmen of Indian descent who, with the help of international development agencies like the World Bank, had built processing factories around the lakeshore. The businessmen exported the fish from the airports of Mwanza, Kisumu and Entebbe to Europe, Asia and the Middle East. Once again, fishermen came from all corners of East and Central Africa to join the gold rush. They came from Tanzania, Kenya and Uganda, the three countries that border the lake. They came from Burundi, Rwanda and Congo, and from far-off Malawi, Mozambique and Zambia. By the mid-1990s, fishermen in the Tanzanian half of the lake alone were catching nearly two hundred thousand tons of sangara each year – thirty times the total annual tonnage of fish caught in North America’s Great Lakes.

The islands of Ukerewe were at the heart of this new boom. Six of the seven original families of Kweru Mto abandoned the land to try their luck on the lake. Farmers from across the archipelago followed them, leaving their crops to wither as they climbed unsteadily into boats. New languages were heard on the islands, from elsewhere in Tanzania and from beyond the country’s borders. On the beaches, fishing camps sprang up; some were temporary, others became permanent. Islets that had never before been inhabited now played host to thriving villages. The lake region was for the first time awash with cash, and the threat of hunger evaporated.

It was not only fishermen and their families who benefited. Those with different skills or who were too old or frail to go out on the lake forged a living building boats, making and mending nets, unloading, weighing, drying and transporting fish, and cooking for fishermen. The sangara created a quarter of a million new jobs on and around Lake Victoria and generated hundreds of millions of dollars in export earnings. Once again, the perch was revered on the Nile – grateful islanders nicknamed it the “Saviour Fish.”

Find out more and purchase a copy of Mark’s book here.

Share This Article