Extracted from a report from Ciro Porto und Valdemar Sibinelli from "Terra da Gente", August edition No.16, 2005
The Amazon fluvial system hosts about 2500 known fish species. Among them are some of the biggest freshwater fishes of the world, e.g. the 300 kg reaching Piraíba (Brachyplatystoma filamentosum) and the Pirarucú (Arapaima gigas) with an average weight of 150 kg. However, it is estimated that about 3000 more species are waiting to be discovered by science. Diversity of species does not stand for a high density of population. The opposite is the case. The enormous biodiversity of the Amazon region emerged because of poor food supply. The flora and fauna had to accommodate and specialize itself to survive. This is exactly what happens in the black water rivers like the Rio Negro (Portuguese for "black river"), which are poor in nutrition. They drain the swamp forests of the Terra Firme, where they wash away the pre-forms of humus impeding thus composition of a proper humus layer, whereby the rivers obtain its coffee like coloring. The washed-away humic acid makes the water extremely acerbic, the pH-value is about 4. Acidity is further increased by decaying leaves. Black water forest and rivers host a reduced number of animals. The rivers were also called "rivers of hunger" by their first discoverers. On the other hand, the river population remains relatively untroubled by mosquitoes and other insect plagues.
Fish always represented an important source of protein for the native population of the region at the upper Rio Negro. A survey conducted among by the Federation of Indigenous Organizations at the Rio Negro (Foirin) in 1997 to 1998 showed. that the biggest problem for the native people is the reduction of the fish population through over-fishing, caused by a untypical high population growth among the Indians and, as a consequence, a higher food demand.
Hereupon Foirin initiated together with another NGO, the Social-Ecological Institute (ISA), and specialists of the center for tropical fishes at the Institute for Environment and Sustainable Natural Resources of the national environment agency IBAMA the project for artificial fish breeding at the upper Tiquié. Technicians of this institute taught the Indios of the Tukano, Tuzuca and of the Maku tribes all necessary steps for the artificial reproduction. After 5 years of activities in laboratories amidst the jungle, on the upper reaches of the Rio Negro, the extinction of fish - a basic food supply in Amazonia - in the black water region, could be prevented.
Before preparing the caught fish for cooking, its sexual organs are extracted and hormones are injected into the female fish. The whole operation however is not that easy as it seems. The dense forest makes the selection of suitable locations for the breeding basins difficult. Considerable fluctuations of the water temperature of some of the igarapés (flooded areas) lead to high loss of spawn. In addition, the great distances between the laboratories and the spawning grounds hamper a regular control. In this case, the knowledge of the Indios does not help very much, because by tradition they are not experienced in live stock breading and husbandry. Nevertheless, a close work between them and the scientist is indispensable. Last but not least, there is insufficient or no scientific knowledge of many species that cannot be researched adequately because of lack of founding and time. At this point, the knowledge and experience of the native Indians leads to new conclusions.
Purchasing additional feeding stuff is complicated due to the lack of funds. Production quotas therefore are too low to be sold-off as surplus to the market. In any case, the main subject of the project is to grant food supply to the native population. Manioc roots as well as termites and ants are fed as protein. As a positive and welcomed side effect, the trapping of leafcutter ants reduces damaging of the plantations.
The project proves that, despite all the difficulties, sustainable economic activities and environment conservation, including the native, indigenous population, is possible. The successes of the Indios at the upper Tiquíe persuaded them to pass their experiences to other tribes in the region to open other breeding stations. Today, about 82 of these stations exist. The medium term planning is to establish 80 more stations in the upper Rio Negro region.