Brazil is facing an energy crisis (specifically electricity). They have plans to build or are building many hydroelectric dams on the river systems. These are the same rivers that many of the Brazilian rays that are traded for ornamental use come from. Even with limited information out there, it seems that the rays are actually benefiting from the damming of these rivers. I'll ppst an excerpt from an article below. I have read several times that stingrays actually increase in number dramatically after a river system is dammed. Unfortunately, other fish do not share the same fate but it is at least encouraging that the rays are thriving despite the man made obstruction. The gene pool will definitely be disrupted, but news that the Henlei is increasing in number isn't what I would consider a negative side effect.
Excerpt:
Case study of the Tucuruí Dam
The present Brazilian electrical crisis and the subsequent demand for the construction of hydroelectric powerplants has raised questions about the effects of dams on freshwater fishes, especially stingray populations. Currently there are 21 dams under construction, and Brazilian scientists are running against time in order to collect as much biological and ecological data as possible, to measure the effects on fish populations. The Tucuruí Dam, closed in 1984, has completely prevented the interchange of stingrays between the Tocantins and Pará rivers.
The Tocantins River is also home to the endemic stingray species Potamotrygon henlei, a precious black and white spotted ray for aquarists. Seventeen years since the dam closure, local fishermen report that piranhas and stingrays, especially P. henlei, have increased abruptly in number, while some teleosts have disappeared and others decreased in size. The stingrays (P. henlei) have learned to eat the meshed fishes caught in the gillnets, and fisherman do not kill them since their meat has no commercial value in the region. Although preliminary evidence indicates a positive situation for P. henlei in the reservoir area, the same cannot be confirmed for P. orbignyi or Paratrygon aiereba, since the implications of the interrupted genetic flux between Tocantins and Amazonas populations can only be speculated at this time.
Neotropical Freshwater Stingrays: diversity and conservation status
Patricia Charvet-Almeida1, Maria Lúcia Góes de Araújo2, Ricardo S. Rosa3 and Getúlio Rincón4
1MPEG, Belém; 2UA, Manaus; 3UFPB, João Pessoa; 4UNESP, Rio Claro, Brazil
Brazil will build the power plants. If they are truly facing a crisis, then there will be no consideration on the affect on wildlife. Let's face it, if you had to choose between electricity and your local river's wildlife population, you would choose the former. They are doing the same.
Excerpt:
Case study of the Tucuruí Dam
The present Brazilian electrical crisis and the subsequent demand for the construction of hydroelectric powerplants has raised questions about the effects of dams on freshwater fishes, especially stingray populations. Currently there are 21 dams under construction, and Brazilian scientists are running against time in order to collect as much biological and ecological data as possible, to measure the effects on fish populations. The Tucuruí Dam, closed in 1984, has completely prevented the interchange of stingrays between the Tocantins and Pará rivers.
The Tocantins River is also home to the endemic stingray species Potamotrygon henlei, a precious black and white spotted ray for aquarists. Seventeen years since the dam closure, local fishermen report that piranhas and stingrays, especially P. henlei, have increased abruptly in number, while some teleosts have disappeared and others decreased in size. The stingrays (P. henlei) have learned to eat the meshed fishes caught in the gillnets, and fisherman do not kill them since their meat has no commercial value in the region. Although preliminary evidence indicates a positive situation for P. henlei in the reservoir area, the same cannot be confirmed for P. orbignyi or Paratrygon aiereba, since the implications of the interrupted genetic flux between Tocantins and Amazonas populations can only be speculated at this time.
Neotropical Freshwater Stingrays: diversity and conservation status
Patricia Charvet-Almeida1, Maria Lúcia Góes de Araújo2, Ricardo S. Rosa3 and Getúlio Rincón4
1MPEG, Belém; 2UA, Manaus; 3UFPB, João Pessoa; 4UNESP, Rio Claro, Brazil
Brazil will build the power plants. If they are truly facing a crisis, then there will be no consideration on the affect on wildlife. Let's face it, if you had to choose between electricity and your local river's wildlife population, you would choose the former. They are doing the same.
