Characteristics
There are 8 major ecosystems in Cuyabeno: (1) seasonally flooded forests or swamps, traversed by sediment-poor black-water rivers with a vegetation dominated by Mauritia flexuosa palms; (2) forests flooded by sediment-rich rivers, or varzea (Pires and Prance, 1985); (3) semi-perminently inudated forests flooded by black-water rivers, or igapó (Pires and Prance, 1985) and dominated by the famous Macrolobium trees which are the homes to countless Epiphytes, Herons, blue and Yellow Macaws and Huatzins; (4) well-drained forest located on small hills in the upper watershed and the áreas between the semi-inundated planes, particularly up-stream from the park entrance at "the Cuayabeno Bridge"; (5) "coffee-and-milk" coloured sediment-rich rivers, the largest being the Río Aguarico; (6) "black-water" sediment-poor rivers, like the tributaries to the Río Cuyabeno; (7) permanent lakes that rarely fall dry, primarily Zancudo Coche along the Río Aguarico; (8) semi-permanent lakes - the largest being the Cuyabeno Lake - that most of the years fall at least partly dry. Black waters (both rivers and lakes) can turn sediment-laden during periods of high rainfall.
All large amazon mammals are present: the lowland Tapirs, two species of Deer, all Amazon cats, including Jaguars and Pumas, Capibaras, two species of Dolphins, Manatees, both otter species, Giant Otter (Pteronura brasiliensis) and Neotropical Otter (Lutra longicaudis), etc. Monkeys are represented by 10 species, while rodents and bats are represented by dozens of species.
The current number of registered bird species is under debate, some claiming 530 species while others suggest that more than 580 species have been observed, but nobody is known to keep sound records. At the peak of the wet season, thousands of hectares of forest become inundated, forming an El Dorado for an estimated number 350 fish species, two species of Caymen, Boa Constrictors and Anacondas, while countless frogs and toads sing their never-ending concerts. Dolphins have been seen swimming deep in the inundated forest during high water, as they follow the fishes.
There are two lake areas in the park. The largest network of lakes is in the eastern part of the park, and can be conveniently reached from Lago Agrio over an asphalt road. The other lake network is located at the border with Peru, and requires some extensive travel. These latter areas have a different flora and fauna than the forests on the higher grounds in between these wetlands and at the upper watershed. While the inundated forests are relatively poor in species, the higher grounds are have some of the highest number of trees per hectare on earth. On one location in neighbouring Yasuní National Park, 307 species of trees/hectare were counted; many more than in all of Europe!
The river system covers the rivers Aguarico, San Miguel and Cuyabeno along with their tributaries. Amongst the Cuyabeno, there is a system of about 14 dark-water lakes. In the rainforest of the Amazon of Ecuador, it is difficult to speak of a rainy season, but a dryer season runs from somewhere mid-December to the end of the middle of March, but the beginning and the end of the dry season varies considerable. The climate corresponds to a wet tropical forest, with precipitation of about 3000 mm or 180 inches per year, and humidity ranging from 85% to 95%. The annual temperature oscillates around 25 C or 77 F.
Read more about this topic: Cuyabeno Wildlife Reserve