<P> In tropical forests, gorillas are hunted to provide meat for the bushmeat trade . Logging also destroys gorilla habitats . Although logging diminishes gorilla habitats, it may also provide for increased herbaceous vegetation as a result of gaps in the tree cover . Destruction of gorilla habitat may harm the overall forest ecosystem . Western lowland gorillas are seed dispersers, which mean they carry seeds from one place to another, and this trait is beneficial to many of the animals in the forest . Therefore, if there are no western lowland gorillas to disperse the needed seeds to other animals, not only will the gorillas become extinct but so will many other animals, which could over time destroy an entire ecosystem . </P> <P> The western lowland gorilla population in the wild is faced by a number of factors that threaten its extinction . Such factors include deforestation, farming, grazing and the expanding human settlements that cause forest loss . There is a correlation between human intervention in the wild with the destruction of habitats and increase in bushmeat hunting . Another of these factors is infertility . Generally, female gorillas mature at 10--12 years of age (or earlier at 7--8 years) and their male counterparts mature more slowly, rarely strong and dominant enough to reproduce before 15--20 years of age . The fecundity of females, or capacity of producing young in great numbers, appears to decline by the age of 18 . Of one half of captive females of viable reproductive age, approximately only 30% of those had only a single birth . However, these non-reproductive gorillas may prove to be a valuable resource since the use of assisted reproductive techniques aid in the maintaining of genetic diversity in the limited populations in zoos . </P> <P> In the 1980s, a census of the gorilla populations in equatorial Africa was thought to be 100,000 . Researchers later adjusted the figure to less than half because of poaching and diseases . Surveys conducted by the Wildlife Conservation Society in 2006 and 2007 found about 125,000 previously unreported gorillas have been living in the swamp forests of Lake Télé Community Reserve and in neighboring Marantaceae (dryland) forests in the Republic of the Congo . However, gorillas remain vulnerable to Ebola, deforestation and poaching . </P> <P> In 2002 and 2003, there was an Ebola outbreak in the Lossi sanctuary population, and in 2004, there was an Ebola outbreak in the Lokoué forest clearing in Odzala - Kokoua National Park, both in the Republic of the Congo . The Ebola outbreak in the Lokoué forest clearing negatively affected the individuals living in groups and the adult females more than the solitary males, resulting in an increase in the proportion of solitary males to those living in groups . This population decreased from 377 individuals to 38 individuals two years after the outbreak and to 40 individuals six years after the outbreak . The population is still slowly recovering, even today, it is hoped towards a population that has the same demographic structure of an unaffected population, because of new births and breeding groups . This Ebola outbreak also affected the Maya Nord population (52 kilometres northwest from Lokoué) from 400 individuals to considerably fewer . Because of these outbreaks, the International Union for Conservation of Nature (IUCN) updated the status of western lowland gorillas from "endangered" to "critically endangered". </P>

How long do western lowland gorillas live in captivity