The last remaining Mountain Gorillas

The mountain gorilla was listed as endangered on the IUCN Red List

by Lorenzo Ciotti
The last remaining Mountain Gorillas

The mountain gorilla was listed as endangered on the IUCN Red List. Conservation efforts have led to an increase in the overall population of the mountain gorilla in the Virungas and in Bwindi. The combined population is now believed to be over 1,000 individuals.

In December 2010, the official website of the Virunga National Park announced that the number of mountain gorillas living in the trinational forest area of which Virunga is a part, has increased by 26.3% over the past seven years, a growth rate average of 3.7% per year.

The 2010 census estimated that 480 mountain gorillas inhabited the region. The 2003 census had estimated the Virunga gorilla population to be 380 individuals, which represented a 17% increase in the total population since 1989, when there were 320 individuals.

The population has nearly doubled since its lowest point in 1981, when a census estimated there were only 254 gorillas left. The 2006 census in Bwindi indicated a population of 340 gorillas, which represents a 6% increase in total population size since 2002 and a 12% increase from 320 individuals in 1997.

All of these estimates were based on traditional census methods using manure samples. collected in night nests. In contrast, genetic analyzes of the entire population during the 2006 census indicated that there were only around 300 individuals in Bwindi.

The discrepancy highlights the difficulty of using inaccurate census data to estimate population growth.

The last remaining Mountain Gorillas

According to computer modeling of their population dynamics in both Bwindi and the Virungas, gorilla groups that were habituated to research and ecotourism have higher growth rates than unaccustomed gorillas.

Habituation means that through repeated, neutral contact with humans, gorillas exhibit normal behavior when people are around. Accustomed gorillas are watched more closely by field personnel and receive veterinary care for traps, respiratory illnesses, and other life-threatening conditions.

However, the researchers have recommended that some gorillas remain de-habited as a betting hedging strategy against the risk of human pathogen transmission throughout the population. The main international non-governmental organization involved in mountain gorilla conservation is the International Gorilla Conservation Program, established in 1991 as a joint effort of the African Wildlife Foundation, Fauna & Flora International, and the World Wide Fund for Nature.

Conservation requires work on many levels, from local to international, and involves protection and law enforcement as well as research and education.