The forests in the reserve have been largely untouched, particularly on the wetter southern slopes of the mountain.

At the lower levels, below 700 metres (2,300 ft), the reserve is covered by closed rain forest rich in species of vegetation.
Above this, up to 2,000 metres (6,600 ft) in elevation, there is montane forest with many creepers and epiphytes growing on the trees.
 The reserve also contains Araliaceae and Arecaceae (palm tree) forests.

The original lowland rain forests typically have tall trees of up to 50 metres (160 ft) emerging from a canopy of around 30 metres (98 ft).
 The understory is relatively sparse.

The most dominant trees are in the Ficus genus.
 Other trees belongs to the Chrysophyllum, Milicia, Ricinodendron and Euphorbiaceae genera.

The Gran Caldera de Luba has much the highest density of fauna on the island due to its inaccessibility to hunters, who must walk for two days to reach the crater.

A 2001 report said that 120 species of birds had been identified so far, including 36 that are endemic races on Bioko.

Fernando Po batis is an endemic species found only in the lowland forest.
Larger hunted species such as black-casqued wattled hornbill and hadada ibis are only found in this part of Bioko.

The reserve is home to Ogilby's duiker, whose long-term survival may depend on enforcement of protection in the Gran Caldera de Luba reserve.

Endangered green sea turtles lay their eggs in nests on the beaches.

Other threatened turtle species that nest on the beaches are the hawksbill sea turtle, olive ridley sea turtle and leatherback sea turtle.

The density of the primate populations in the crater, at 1.2 to 3.3 encounters per square kilometer, are among the highest in Africa.

Five of the primate species are of global conservation concern: Preuss's monkey, red-eared guenon, black colobus, western red colobus and drill.
The reserve may be home to the largest surviving population of drill.

According to the Primate Specialist Group of the IUCN Species Survival Commission, the island is the most important location in Africa for conserving diversity of primates.
 Pennant's colobus, a type of red colobus, is one of the most endangered primates in the world.

There are no viable captive populations of the subspecies of monkey found on Bioko.
 
Attempts to raise black colobus and red colobus in captivity have failed.
The forests in the reserve have been largely untouched, particularly on the wetter southern slopes of the mountain.
At the lower levels, below 700 metres (2,300 ft), the reserve is covered by closed rain forest rich in species of vegetation. Above this, up to 2,000 metres (6,600 ft) in elevation, there is montane forest with many creepers and epiphytes growing on the trees.  The reserve also contains Araliaceae and Arecaceae (palm tree) forests.
The original lowland rain forests typically have tall trees of up to 50 metres (160 ft) emerging from a canopy of around 30 metres (98 ft).  The understory is relatively sparse.
The most dominant trees are in the Ficus genus.  Other trees belongs to the Chrysophyllum, Milicia, Ricinodendron and Euphorbiaceae genera. 
The Gran Caldera de Luba has much the highest density of fauna on the island due to its inaccessibility to hunters, who must walk for two days to reach the crater.
A 2001 report said that 120 species of birds had been identified so far, including 36 that are endemic races on Bioko. 
Fernando Po batis is an endemic species found only in the lowland forest. Larger hunted species such as black-casqued wattled hornbill and hadada ibis are only found in this part of Bioko.
The reserve is home to Ogilby's duiker, whose long-term survival may depend on enforcement of protection in the Gran Caldera de Luba reserve.
Endangered green sea turtles lay their eggs in nests on the beaches.
Other threatened turtle species that nest on the beaches are the hawksbill sea turtle, olive ridley sea turtle and leatherback sea turtle.
The density of the primate populations in the crater, at 1.2 to 3.3 encounters per square kilometer, are among the highest in Africa.
Five of the primate species are of global conservation concern: Preuss's monkey, red-eared guenon, black colobus, western red colobus and drill. The reserve may be home to the largest surviving population of drill.
According to the Primate Specialist Group of the IUCN Species Survival Commission, the island is the most important location in Africa for conserving diversity of primates.  Pennant's colobus, a type of red colobus, is one of the most endangered primates in the world.
There are no viable captive populations of the subspecies of monkey found on Bioko.  
Attempts to raise black colobus and red colobus in captivity have failed.
Luba Crater Scientific Reserve