The Great Savannah harbors diverse and unique flora and fauna as well as several endemic species. Biogeographic evidence suggests that the area was probably a "Pleistocene refuge" during the glacial periods, which resulted in autochthonous flora represented by at least 41 endemic species, including the yagrumo Cecropia kavanayensis (Steyermark 1979). There are many keystone fauna species and species of conservation interest, including the jaguar (Panthera onca), tapir (Tapirus terrestris), harpy eagle (Harpia harpyja), and two Venezuelan endemics, Tyler´s mouse opossum (Marmosa tyleriana) and the Roraima mouse (Podoxymis roraimae) (Huber and Febres 2000).

Vegetative formations typical of the Guiana Shield-those that grow on acidic soils derived from sandstone decomposition, which are nitrogen, phosphorus and potassium poor but aluminum rich-are found in the Eastern Sector of Canaima National Park. Savannahs and riparian forests dominate along the rivers and creeks. Typically, herbaceous plants cover the savannah and only occasionally do isolated trees or small groups of trees interrupt this coverage. Depending on the soil and altitude conditions, there are savannahs with moriche palms and shrub savannahs (Huber and Febres 2000, Michelangeli undated).

           
In the savannahs with palms, the dominant element is the moriche palm (Mauritia flexuosa)

In the muddy, palm savannahs, grasses like Andropogon, Eriochrysis, Panicum and Sorghastrum thrive. The dominant tree is the moriche palm (Mauritia flexuosa), locally known as kuai, and is used frequently by Pemón indigenous communities.  (Other common English names for this tree include mauritia palm and aguaje palm.)  Small bodies of water form in the lowest portions of the palm groves, and diverse aquatic plant groups grow-both submerged and floating-including Azolla, Salvinia, Lemna, Nympha, Sagittaria, Echinodorus, Mayaca, Tonina, Utricularia, Urospatha, Ludwigia and Montrichardia (Michelangeli undated).

In the bush savannahs, the grasses (Gramineae) grow in bunches over dry, sandy, quartzous and rocky soils. Common genera include Axonopus and Trachypogon. Other typical plants include Scleria cyperina and Bulbostylis paradoxa, a  with cylindrical stems that grows in clumps. Woody shrubs include Bowdichia virgilioides, Byrsonima crassifolia, Anacardium occidentalis, Casearia sylvestris, Palicourea rigida, Byrsonima verbascifolia and Manihot triste. In the wetter and muddier zones, broad-leafed plants such as species of the Stegolepis genus are common (Huber and Febres 2000, Michelangeli undated).

Riparian forests grow along the rivers and are influenced by periods of flooded banks and increased water levels. During the rainy season, these forested strips are partially submerged. Trees in these forests grow between 15 and 20 m. Typical species include members of the palm family such as Euterpe precatoria and moriche (Mauritia flexuosa); species of the Bombacaceae family: ceibón (Bombax s.), and Guiana chestnut (Pachira aquatica); Campsiandra comosa, Dimorphandra davisii, Macrolobium bifolium, Pterocarpus officinalis of the Fabaceae family; Garcinia madruno of the Clusiaceae family: Eugenia punicifolia of the Myrtaceae; Remijia densiflora of the Rubiaceae family; and Pouteria canaimensis of the Sapotaceae family (Michelangeli undated).

On the summits of the tepuyes, tepuy forests grow. Typically, the trees are only 6 to10 m high and have thick canopies formed almost entirely by coriaceous leaves. Plants of the following genera (among others) grow here: Schefflera, Ocotea, Ficus, Rapanea, Podocarpus, Pagamea, Protium, Oxythece, Clethra, Didimopanax, Aldina, Macrocarpea, Drimys, Erythroxylum and Weinmania. These forests can grow in different habitats, such as in sunny areas, over sandstone or igneous substrates, in dry areas, or in areas close to waterways. Close to the waterways, there are additional species of the following genera: Aspidosperma, Amanoa, Aiovea, Cyrilla, Digomphia, Hieronyma, Pithecellobium, Rapanea, Remijia and Spathelia. Tree ferns and palms also do well here, such as Geonoma appuniana and Euterpe caatinga. The understory includes dense or sparse Bromeliaceae (Ayensua, Bocchinia), Eriocaulaceae (Syngonanthus) and insectivore plants (Drosera, Heliamphora and Utricularia) (Michelangeli undated).

In the Lema Mountains, there are evergreen basimontane forests 600 to 700 m, with trees growing to 25 to 30 m high, with irregular canopies. Dominate families include leguminous, Lauraceae, Apocynaceae and Moraceae, among others. Between the altitudes of 700 and 1,400 m, there are several types of submontane evergreen forests (montane up to the summits). Trees grow between 10 and 15 m, canopies are very dense, with coriaceous leaves and frequent epiphytes. Tree families include Theaceae, Rubiaceae (Isertia hypoleuca), Euphorbiaceae, palms and Melastomataceae (Miconia superba). Colonies of the Rapataceae (Stegolepis steyermarki) are found in the understory, with colorful yellow ochre flowers. Shrubs growing on exposed rocks are mostly of the Rubiaceae, Clusiaceae, Melastomataceae and Ochnaceae families. A notable species is the giant terrestrial bromeliad (Brocchinia micrantha) (Michelangeli undated).

Of the mentioned floral species, the moriche palm is considered "vulnerable" in Venezuela because its palm frond is intensely harvested and because of habitat destruction for agricultural, grazing and petroleum activities. The palmito (Euterpe precatoria) is also considered vulnerable because of habitat loss and probable overharvest of the heart of palm (Llamozas and col. 1993).

Of Venezuela's 351 mammal species, 145 have been registered in Canaima National Park. Some of these species are widely distributed throughout the country, such as the southern opossum (Didelphis marsupialis), tapir (Tapirus terrestris), collared peccary (Tayassu tajacu), jaguar (Panthera onca) and some bats. Other species' distributions are restricted to the Guiana Shield, like the pale-throated three-toed sloth (Bradypus tridactylus), lesser ghost bat (Diclidurus scutatus), chestnut long-tongued bat (Lionycteris spurelli), the white-footed climbing mouse (Rhipidomys leucodactylus), and two animals endemic to Venezuela, Tyler´s mouse opossum (Marmosa tyleriana) and Roraima mouse (Podoxymis roraimae). From an ecological point of view, one mammal group in the park requires forest coverage and includes rodents (paca, agouti and squirrel), bush dog (Speothos venaticus), Coatimundi (Nasua nasua), southern tamandua (Tamandua tetradactyla) and the giant armadillo (Priodontes maximus). The other mammal group inhabits the upper tepuyes herbaceous areas and savannahs and includes species like the short-tailed cane mouse (Zygodontes brevicauda), Brazilian guinea pig (Cavia aperea), crab-eating fox (Cerdocyon thous), jaguarundi (Herpailurus yagouaroundi), lutrine opossum (Lutreolina crassicaudata) and Pallas's mastiff bat (Molossus molossus) (Huber and Febres 2000, Linares 1998, Ochoa and col 1993).

Of the 1,323 bird species registered in Venezuela, 495 have been reported in the Great Savannah. The forests have the greatest diversity, where it is more difficult to see birds like parakeets, antbirds, ovenbirds, cotingas, cock-of-the-rock and some thrushes. Birds such as hawks, nighthawks, savannah seedeaters, parakeets and others inhabit the savannah. There is high bird endemism in the Great Savannah; one notable species is the Tepui tinamou (Crypturellus ptaritepui) that is only known to inhabit the Sororopán and Ptari tepuyes (BirdLife International 2003). Several Northern migratory species winter in the Great Savannah, such as spotted sandpiper (Actitis macularia), barn swallow (Hirundo rustica) and blackpoll warbler (Dendroica striata). There are also several Australian migrants such as the small-billed elaenia flycatcher (Elaenia parvirostris), variegated flycatcher (Empidonomus varius) and the lined seedeater (Sporophila lineola) (Lentino 1997, Lentino and col. 1996).

Regarding the herpetofauna, more than 60 amphibian (frogs, toads and caecilians) and 70 reptile (turtles, crocodiles, lizards and snakes) species have been identified. Notable endemic species are those of the Oreophrynella genus, which is a group of small toads living on the tepuyes; the Tepuihyla genus, which are white-lipped frogs; and the small lizard of the Riolama genus, among others (Gorzula and Señaris 1998, Huber and Febres 2000).

Fifty-two fish species have been registered, grouped in 5 orders and 17 families widely distributed in all of the Great Savannah's rivers. There are also 14 endemic species in the zone (Lasso 1989, Huber and Febres 2000).

The following table provides a summary of threatened fauna species inhabiting the park and their level of threat at the national and international levels.

Common name	Scientific name	Venezuela threatened status	Global threatened status
Giant Armadillo	Priodontes maximus	Endangered	Endangered
Giant Anteater	Myrmecophaga tridactyla	Vulnerable	Vulnerable
Tapir	Tapirus terrestres	Vulnerable	Vulnerable
Bush dog	Speothos venaticus	Vulnerable	Vulnerable
Little spotted cat	Leopardus tigrinus	Vulnerable	Almost threatened
Ocelot	Leopardus pardalis	Vulnerable	Not listed
Margay	Leopardus wiedii	Vulnerable	Not listed
Jaguar	Panthera onca	Vulnerable	Lesser risk, almost threatened
Roraima mouse	Podoxymis roraimae	Lesser risk, less concern	Not listed
Latrine opossum	Lutreolina crassicaudata	Lesser risk, less concern	Not listed
Harpy eagle	Harpia harpyja	Vulnerable	Lesser risk

Sources: Cat Specialist Group (2001), Downer, C. & Castellanos, A. (2001), Edentate Specialist Group (1996), Rodríguez and Rojas-Suárez (1999).