"People come and go on the river, but love the beauty of sea bass." The poem mentions that the sea bass is delicious. But in fact, most of the perch fish are carnivorous fish, very fierce, so the meat is also delicious. The Chinese perch's distant relative in Africa, the Nile perch, is a bit unpopular, killing other fish and causing many local fish deaths.
Lake Victoria in Africa is the second largest freshwater lake in the world and is an ancient lake with many rare fish. But an uninvited guest brought their end to life ahead of schedule.
The uninvited guest was Africa's famous Nile perch. The Nile perch is a large freshwater fish native to Africa, with an average body length of about 1.2 meters for mature Nile perch. Originally grown on the Congo, Nile, Senegal and Chad rivers, it was introduced in the 1950s to Lake Victoria, the largest freshwater lake in Africa (and the second largest in the world), in East Africa. Because the Nile perch is a fast carnivorous fish species, large and fast-growing, it soon multiplied in large numbers on Lake Victoria and left hundreds of other species of fish and aquatic animals in the lake extinct or endangered, with only those living in the crevices and shallow waters spared. (They even eat juvenile fish of the same kind.)
Nile perch (Lates niloticus) Nile perch, or Nile perch for short, is known in English as Nile Perch. It is a genus of perch perch and is a very ferocious predatory fish and the largest freshwater fish in Africa. It is widely distributed in the major rivers throughout tropical Africa and is introduced to Lake Victoria, as well as reservoirs in many areas. They are found in Lake Chad, Congo, Nile, Senegal, Turkana and other river basins, and have also been found in the brackish waters of Lake Mareotis in Egypt. Its common names include African Snook, as well as a large number of names in different Languages in Africa.
The orange area of the map is the origin of Nile perch, and the light orange area is the area of Nile perch invasion.
Nile sea bass fillets exported to Europe
The rapid reproduction of Nile perch in Lake Victoria has led to a rapid increase in nile perch fishing production, which has led to the rapid development of local fishing and fillet processing industries, and has greatly benefited fishermen and operators in the three countries along the lake (Kenya, Uganda and Tanzania), and the Nile perch industry has thus become a pillar industry in the three local countries. Nile perch is exported to Europe and is mainly processed into fillets in the countries of origin, mainly 200-800 grams of chilled fillets and 500-1200 grams of frozen fillets. In 2003, the export value of Nile perch to the Eu amounted to 169 million euros.
The Nile perch is silvery with a pale blue tinge. They have particularly black eyes with a bright yellow outer ring. They are one of the largest freshwater fish, reaching a maximum of almost 2 meters and weighing up to 200 kg.
Adults can inhabit lakes with ample oxygen, while juveniles are confined to coastal or barrier areas. Nile bass are ferocious predators, feeding on fish (including their own kind), crustaceans and insects; juveniles feed on zooplankton.
Although the Nile perch is an invasive species, in Africa, the Nile perch is mainly processed into frozen fillets for export to the European market and is the absolute king of exported aquatic products. The Nile perch is large, the flesh is white and delicate, the intermuscular spines are few, and the taste is neutral, which is very in line with the European requirements for white meat fish and white meat fillets. In Uganda, Nile perch exports sometimes outpace coffee exports, making it the largest agricultural export. Uganda exports 90 per cent of freshwater fish, including Nile perch and less than 10 per cent of Nile tilapia, mainly to the Netherlands, Belgium, the United Kingdom and Germany. According to scientists, Nile perch are rich in a substance called "omega type 3 unsaturated fatty acids". This substance is beneficial to our human cardiovascular and cerebrovascular systems, can clear blood lipids, lower blood pressure and alleviate symptoms of arrhythmia.
Due to the great economic value of Nile perch, it is extremely important for the local aquaculture industry. The Rohe perch was introduced to Lake Victoria in East Africa in 1954 for economic (fishing and food) purposes.
The red dot is Lake Victoria's location in Africa, the second largest freshwater lake in the world
The introduction of the Nile perch has caused the complete extinction or near extinction of hundreds of native fish species in Lake Victoria, and there are more than 200 species of endemic fish species in Lake Victoria, which have become completely extinct in the wild due to the predatory and competition of the Nile perch, and only a few species are still kept in aquariums in North America and Europe, waiting for possible future restoration work. Nile perch production is also decreasing due to overfishing; this gives some of the remaining native species a breathing space. Originally, nile bass fed on native cichlids, but due to a sharp decline in food diversity, Nile perch currently feeds mainly on small shrimp and carps.
The introduction of the Nile perch, while an ecological catastrophe for Lake Victoria, also stimulated the development of local fisheries. In 2003, nile perch was sold at €169 million in the European market, but the future outlook for the fishery remains uncertain.
Local residents are processing Nile perch
Since the 1990s, nile perch populations and production have been decreasing year on year due to overfishing (and a total collapse of the ecosystem). On the other hand, changes in indigenous ecosystems also have an impact on the local socio-economic situation. Large-scale fishing companies, as a result of the export of Nile perch, earn millions of dollars; the local traditional fishery is gradually declining or replaced, and the income from selling fish goes into the pockets of large companies, and local residents have little ability to spend their fish.
Processing plants set up in Africa by developed countries are processing Nile perch for export to Europe
The Academy Award-nominated documentary Darwin's Nightmare (a French-Austrian-Belgian work, 2004) explores the devastation caused by the introduction of the Nile perch, including weapons purchased (imported from Europe) from the export of sea bass, deepening local conflict and poverty.
The Lake Victoria Fisheries Organization pointed out that the excessive use of illegal fishing equipment in recent years has been the main reason for the decline in production, and the use of illegal fishing equipment such as small nets has led to the capture of a large number of juvenile fish that have not grown, destroying the hatching area of fish species in the lake area. Generally speaking, Nile perch with a body length of more than 50 cm are considered adults, but today nile perch with a body length of only 20 cm can often be seen in many aquatic markets near the lake area.
This carnivorous fish eats fiercely, and after being hooked, it will constantly jump out of the water and try to decouple. The Nile perch is the largest member of the family Cyprinidae, said to have had more than 400 pounds of large fish, and in 2009 Tim Smith, a 39-year-old food teacher from the United Kingdom, caught a 1.8-metre-long, 113-kilogram Nile bass on Lake Victoria and snatched the super seabass from the crocodile's mouth.
Nile perch have been introduced to Lake Victoria before the impact of stocking perch in Lake Kyoga can be assessed. Within 10 years, the river bass of Lake Kyoga had gained a foothold and bred, and by the 1980s, the Nile perch had become the main carnivorous fish on Lake Victoria. They feed on dozens of small species of fish, and several of them have become extinct. The introduction of river bass has brought disaster to native fish in the lake and reduced commercial fishing, but on the other hand, their growth has also provided a good species of weeping fish in the area. We can predict that there will be more fishing records on Lake Victoria.
It is worth mentioning that the Nile perch in the above-mentioned African countries is wild-caught. In recent years, some countries in Africa have begun to farm Nile perch, the most prominent of which is Nigeria. Once a major fishing country for wild Nile bass, Nigeria embarked on a path of combining conservation and farming of wild resources due to declining resources. Farming in Nigeria has been very rapid since 1995, reaching 4 900 tonnes in 2006 and 8 300 tonnes in 2008, and wild Nile perch catches recovering from around 5 000 tonnes in the 1990s to 17 000 tonnes in the same year. The wild breeding and captivity of Nile perch in Nigeria has the potential to become a potential competitor to wild Nile perch and farmed Vietnamese catfish, and even Chinese tilapia, and the future in the European and global markets.
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This article is the original article of "Eight Fresh Crossing the Sea" (ID: baxianguohai88)], unauthorized reproduction is prohibited.