Ucayali River

"Ucayali" redirects here. For other uses, see Ucayali (disambiguation).

Ucayali River
Confluence of the Tambo (from bottom) and Urubamba Rivers (background right) forming the Ucayali River (background left)
Map of the Amazon Basin with the Ucayali River highlighted
Location
Country	Peru
Physical characteristics
Source	confluence of the Tambo and Urubamba Rivers
• location	Atalaya, Ucayali, Peru
Mouth	Amazon River
• location	confluence with Marañón River, Loreto, Peru
Length	2,238 km (1,391 mi) 1,460 km (910 mi)
Basin size	351,549 km2 (135,734 sq mi)
Discharge
• location	Requena, Peru
• average	(Period of data: 1990–2006)13,385 m3/s (472,700 cu ft/s) 13,500 m3/s (480,000 cu ft/s) (Confluence of Marañón: ~13,800 m3/s (490,000 cu ft/s))
• minimum	3,000 m3/s (110,000 cu ft/s)
• maximum	28,000 m3/s (990,000 cu ft/s)
Discharge
• location	Pucallpa, Peru (Basin size: 260,733 km2 (100,670 sq mi)
• average	(Period of data: 1990–2006)8,931.2 m3/s (315,400 cu ft/s)
Basin features
Tributaries
• left	Tambo, Pachitea, Aguaytia, Pacaya, Pisqui, Cushabatay
• right	Urubamba, Tamaya, Tapiche

The Ucayali River (Spanish: Río Ucayali, IPA: [ˈri.o wkaˈʝali]) is the main headstream of the Amazon River. It rises about 110 km (68 mi) north of Lake Titicaca, in the Arequipa region of Peru and becomes the Amazon at the confluence of the Marañón close to Nauta city. The city of Pucallpa is located on the banks of the Ucayali.

Description

The Ucayali, together with the Apurímac River, the Ene River and the Tambo River, is today considered the main headwater of the Amazon River, totaling a length of 2,669.9 kilometres (1,659.0 mi) from the source of the Apurímac at Nevado Mismi to the confluence of the Ucayali and Marañón Rivers:

• Apurímac River (total length): 730.7 km (454.0 mi)
• Ene River (total length): 180.6 km (112.2 mi)
• Tambo River (total length): 158.5 km (98.5 mi)
• Ucayali River (confluence with Tambo River to confluence with the Marañón): 1,600.1 km (994.3 mi)

Exploration

The Ucayali was first called San Miguel, then Ucayali, Ucayare, Poro, Apu-Poro, Cocama and Rio de Cuzco. Peru has organised many costly and ably-conducted expeditions to explore it. One of them (1867) claimed to have reached within 380 km (240 mi) of Lima, and the little steamer "Napo" found its way up the violent currents for 124 km (77 mi) above the junction with the Pachitea River, and as far as the Tambo River, 1,240 km (770 mi) from the confluence of the Ucayali with the Amazon. The "Napo" then succeeded in ascending the Urubamba River 56 km (35 mi) upstream from its junction with the Tambo, to a point 320 km (200 mi) north of Cuzco.

Rubber boom

During the first Amazon rubber boom, the Ucayali River basin and its indigenous inhabitants were heavily exploited for the collection of rubber. One of Peru's first rubber barons, Carlos Fitzcarrald, based his enterprise in the Ucayali and due to his success he became the richest rubber entrepreneur on the river by 1888. Many indigenous tribes along the Ucayali were targeted by rubber barons like Fitzcarrald during Correrias("forays" or "chasings"), which were effectually slave raids. Some of the indigenous groups that were targeted include Asháninka, Amahuaca, Piro [Yine], Shipibo and Conibo. Fitzcarrald's enterprise dominated the area around Atalaya, which is located near the Tambo and Urubamba River's confluence. According to anthropolgist Søren Hvalkof, the "favourite focus of the Atalaya patrons’ correrías" were isolated Asháninka settlements around the Gran Pajonal and Ucayali.

“Cumaria, Peru, head of navigation on the Ucayali River 3,000 miles from the sea.”

The work force in the form of slaves had at this time been converted into a commodity as part of the economy of the region. The correrías after indigenous slaves were common in all parts and involved all of the indigenous groups of the Ucayali. With the booming economy of rubber extraction, in 1880 human exploitation and perversion reached new heights

— Søren Hvalkof, Liberation through land rights

In 1893, Fitzcarrald was credited with establishing the Isthmus of Fitzcarrald, an important portage route between the Urubamba River, a tributary of the Ucayali, and the Manu tributary of the Madre de Dios River. In subsequent years, several other prominent rubber entrepreneurs, like Carlos Scharff and Leopoldo Collazos, attempted to establish portage routes which connected the Ucayali River to the Madre de Dios. The establishment of Fitzcarrald's portage route marked the beginning of Peruvian activity with the rubber trade in the Madre de Dios River basin.

Navigation

The Ucayali's width varies from 400–1,200 metres (1,300–3,900 ft), due to the large number of islands. The current runs from 5–6 kilometres per hour (3.1–3.7 mph), and a channel from 20–50 metres (66–164 ft) wide can always be found with a minimum depth of 1.5 m (4.9 ft). There are five difficult passes, due to the accumulation of trees and rafts of timber. Sometimes large rocks which have fallen from the mountains and spread across the riverbed cause whirlpools.

National Reserve

The Ucayali is home to the Amazon river dolphin, giant otter, and the Amazonian manatee, which are abundant in Pacaya-Samiria National Reserve, close to Nauta. The southeastern border of the reserve is formed by the lower Ucayali River.

The river gives its name to the Ucayali Region of Peru and the Ucayali Province of the Loreto Region.

See also

• Scinax pyroinguinis

References

Bibliography

• Huertas Castillo, Beatriz (2004). Indigenous peoples in isolation in the Peruvian Amazon. The International Work Group for Indigenous Affairs.
• García Hierro, Pedro; Hvalkof, Søren; Gray, Andrew (1998). Liberation through land rights in the Peruvian Amazon. The International Work Group for Indigenous Affairs.