Chimpanzee Extinction Warning

10th July 2010

Chimpanzees are disappearing at a faster rate than originally thought and some subspecies could become extinct within 17-23 years, based on preliminary research conducted at the African sanctuaries that take in orphaned apes.


The Pan African Sanctuaries Alliance (PASA) presented a study today at its 2004 Management Workshop in Johannesburg, South Africa, that revealed chimpanzees in West Africa are facing extinction within the next two decades.


The subspecies Pan troglodytes vellerosus – which is found predominantly in Nigeria – is one of four chimpanzee subspecies, and it is estimated that no more than 8,000 remain in the wild. It is believed that the illegal hunting and eating of apes – known as the “bushmeat crisis” – has had the greatest impact on the rate of decline, along with deforestation, human encroachment, and disease.


“The situation is much more critical than we thought,” said Prof. Norm Rosen, an anthropologist at California State University-Fullerton, who coordinated the study and serves as chairman of the PASA Advisory Board. “The numbers at the sanctuaries don’t lie. You don’t get the kind steady stream of orphaned chimpanzees we’re seeing without a devastating drop in the wild population.”


The study was conducted by using the rate of orphans arriving at sanctuaries to calculate the loss of chimpanzees in the wild. The results were obtained through the use of a simulation program developed by the Conservation Breeding Specialist Group (CBSG), which processes the data over 100 times in order to ensure accuracy.


At present, the 19 PASA sanctuaries care for approximately 670 chimpanzees, a number that has risen by more than 50 percent in the last three years.


Rosen’s study – which is based on the assumption that 10 chimpanzees in the wild are killed for every orphan that reaches a sanctuary – predicts that the vellerosus subspecies will become extinct within the next 17-23 years. The other three chimpanzee subspecies face slightly better odds, but all are expected to disappear within 41-53 years, at the current rate of decline.


PASA was formed in 2000 to unite the sanctuaries across Africa that take in injured, unwanted or confiscated chimpanzees, gorillas, bonobos and other primates.