The own configuration of the island of Cuba, long and narrows, gives place to the existence of rivers of short course and reduced flow in their majority and to a dividing one main of the waters to all the long of the country in two slopes: north and south. The longest river is Cauto and the bigger one is Toa River, and in fact they are hardly creeks compared with the rivers that are come in America of North or South, Europe or any another continent.

Bayate River, at Sierra del Rosario, Pinar del Rio

The most importants rivers are:

River	Longitude (km)	Province
Cauto	370	Granma
Sagua La Grande	163	Villa Clara
Zaza	155	Sancti Spiritus
Caonao	133	Ciego de Avila
San Pedro	124	Camaguey
Jatibonico del Sur	119	Sancti Spiritus
Las Yeguas	117	Camaguey
Cuyaguateje	112	Pinar del Río
Mayarí	106	Holguín
Hondo	105	Pinar del Río
Agabama	105	Sancti Spiritus
Toa	100	Guantánamo

The fluvial basins in a same way are relatively little extension and there are a total of 632 bigger than 5 km² with a fluvial glide of 31 682 million cubic meters. The biggest basins in the country are:

Name of basin	Area (km²)	Area (mi²)
Cauto	9540	3730
Zaza	2413	945
Guantánamo-Guaso	2347	920
Toa	1061	415

Zunzún

The Cuban's flora and fauna are characterized by their great diversity and high endemism level where the influence of insularity and the incredible geologic variety without a doubt with a notable presence of limestone areas, serpentinites, of slates and savannas with quarz sands , gives place to an extensive habitat variety and dissimilar conditions of life as well as to a very diverse mosaic of soils.

 

There have been counted as part of the flora and fauna of Cuba around 32 050 alive organisms although an important part of them are inferior organisms. There are among superior organisms 8 000 species of plants, 7 500 species of insects, 963 of fish, 121 of reptiles, 46 of amphibians, 350 species of birds and 42 of mammals are known. A very important characteristic of the Cuban's flora and fauna is that there are not dangerous species for the man,you can sleep everywhere with all tranquility (with the sure nuisance of the mosquitos, clear) because despite there are 2 species of crocodiles, they don't attack the man (at least without provocation) and the species of sharks that live in the Cuban waters don't share the aggressiveness of their neighbors from Florida. Between the other species of reptiles or amphibians there is not any poisonous and not even aggressive and lastly the mammals besides being scarce are of little size and totally inoffensive.