In 1973, however, a fresh study concluded that the specimens from Bolivia had more teeth than the specimens from elsewhere and that the rapids and water falls of the Madeira River acted as a barrier, effectively isolating the Bolivian population.
Other localized, small populations occur notably on four tributary rivers: the central Tapajós River, lower Madeira River, lower Rio Negro, and lower Ucayali River; also on the Amazon River, one region downstream of the Tapajós-Amazon River confluence.
The Campina Jay is endemic to the Brazilian Amazon where it is known almost entirely from within the Madeira-Purus interfluve in the state of Amazonas.
On the Amazon River its range starts upstream of the Madeira River confluence, but the entire Madeira is its eastern limit in the Basin's southwest quadrant, extending upstream into its tributaries in northern Bolivia.
The range of the Cobalt-winged Parakeet is in the extreme western Amazon Basin in Brazil's states of Amazonas, Acre, and Rondônia, part of the North Region; also from north to south, southernmost Venezuela, eastern Colombia-Ecuador-Peru, and northern and central Bolivia, and in Bolivia within the tributary rivers to the Madeira River flowing northeast to the Amazon River.
Near the Amazon River, its range extends east to about the Madeira River, while in the southern half of its range it extends east to the Xingu River.
The type locality of Drymaeus branneri is above Porto Velho along the Madeira-Mamoré railroad (= ca. 260 km South-West of Porto Velho), Rondônia, Brazil.
The Gilded Barbet ranges in the eastern Andes drainages to the rivers of the western Amazon Basin from eastern Colombia-Venezuela, eastern Ecuador, from north to south-eastern Peru, and northern Bolivia; in Bolivia the Barbet only ranges on the headwater tributaries to the north-easterly flowing Madeira River.
Notable achievements include: in 1879 as a Lieutenant, he commanded the survey of the Madeira River, in the Amazon.
The contiguous range has three extensions; a southerly extension from southern Peru into central Bolivia; it is about 2000 km long and 400 km wide, and in Bolivia covers the upper reaches of tributary rivers to the northeast flowing Madeira River.
Populations found in the south-eastern Amazon Basin (south of the Amazon River and east of the Madeira River) were formerly included in this species, but were described as a new species, the Cryptic Forest Falcon, in 2003.
The range in Bolivia is bifurcated; in the north, the Long-tailed Potoo is found on the headwater rivers to Brazil's Amazonas state's Madeira River; in northeastern Bolivia, the bifurcated range extends only to the mountain headwaters of another tributary of the Madeira, the Brazilian-Bolivia Guaporé River.
It has two subspecies: The widespread nominate has a white rump and is found south of the Amazon River and west of the Madeira River, while ochroptera has a yellowish rump and is found between the Amazon River and the lower Rio Negro.
Madeira-Mamoré Railroad (365 km; 227 mi) along the huge rapids of upper Madeira
He was descendent of the Suárez brothers "rubber barons", who had been responsible for the extermination of the Caripuña people on the Madeira River in Bolivia (Tully, p. 404).
This corridor is about 700 km wide, and includes the confluence areas downstream of the major rivers: Rio Negro, Madeira, Tapajós, Xingu, and the outlet section of the Tocantins River in the southeast Basin's neighbouring river system, Araguaia-Tocantins.
He might then, by his knowledge of bird ranges, state where the tape had been made—Zimmer gives the example of "south bank of the Amazon between the Rios Madeira and Tapajos".
Another species, the White-tailed Tityra (Tityra leucura), is generally considered a variant of the Black-crowned Tityra, but recent evidence suggests it may be a valid species restricted to the Brazilian Amazon near the Madeira River.
In the southwest Amazon Basin, the Tui Parakeet ranges more widely, it being present in the vicinity of several large rivers such as the Solimões River, Madeira River, Madre de Dios River, Purús River, Juruá River, Ucayali River and lowermost Marañón River.
Rodrigues (2007) considers the Proto-Tupian homeland to be somewhere between the Guaporé and Aripuanã rivers, in the Madeira River basin.
In Bolivia, on the Brazil-Bolivia border river the Guapore, the range bifurcates and is found only at the headwaters of the Guapore, and in the northern Bolivia-Peru region where the Guapore joins the headwater rivers of Brazil's Amazonas state's Madeira River.
The White-eared Puffbird's range encompasses nearly all of northern Bolivia, the Madeira River's many headwater tributary rivers; also the extreme headwaters of the Tapajós River.
The main range of the White-winged Potoo is the central Amazon Basin at the confluence of four rivers, from the Rio Negro on the north, to the Madeira River on the south, in eastern regions of Brazil's Amazonas state.
Mississippi River | River Thames | Amazon River | Columbia River | Madeira | Hudson River | Colorado River | Potomac River | river | Ohio River | Missouri River | Delaware River | Murray River | River Tyne | Madeira River | Volga River | River Nene | River Clyde | River Trent | River Severn | Amur River | River Wear | Allegheny River | Red River | Dnieper River | Yarra River | Paraná River | River Tees | Fraser River | Yangtze River |
The three largest projects studied, Jirau, Santo Antônio and Belo Monte, are already beyond the feasibility phase: In 2007, Ibama, the environmental agency, gave approval for the construction of two new dams, Jirau (3,300 MW) and Santo Antônio (3,150 MW), on the Madeira River in the state of Rondônia.
Gibbon's study concluded that a rail-road along the Madeira river rapids would allow efficient transport of goods from the Bolivian capital of La Paz to US markets.
It is found in northern Bolivia (Beni Department and Santa Cruz Department) and Brazil (in the southern Amazon between the Tocantins River, Xingu, Tapajós, and Madeira Rivers).
The rivers in the Amazon Basin, going upstream are the following: Amazon River, (Tocantins, Araguaia— east of the Xingu), Xingu River, Madeira, and Marañón-Ucayali, (in Amazonian Peru).
Roosmalens' dwarf marmoset (Callibella humilis or Callithrix (Calibella) humilis), also known as the black-crowned dwarf marmoset, is a small New World monkey native to the Amazon Rainforest, on the east bank of the lower Madeira River, and the west bank of the Aripuanã River, in Brazil.