But international smuggling from neighboring Nigeria into Cameroon does not appear widespread, State University of New York at Albany researchers said in BioMed Central's journal BMC Ecology.
Working with Limbe Wildlife Center in Limbe, Cameroon, the U.S. researchers put genetic information from rescued chimps into a computer program that mapped their origins, comparing genetic sequences from rescued chimps with those of their wild counterparts across several areas of Cameroon and Nigeria.
"We found that all the rescued chimps were from Cameroon, implying that international smuggling is less of a problem than local trade," the researchers said in a statement.
"Worryingly though, the problem seems to occur throughout Cameroon, with some rescued chimps even coming from protected areas," they said, observing that a smuggler can get $100 for a live chimp in Cameroon and $20,000 on the international black market.
Since as many as 10 chimpanzees are killed for every one that's rescued, the study's findings could have a significant impact on the restoration of the population, the researchers said.
The genetic information from the rescued chimps will also help to reunite them with their relatives in the wild, the researchers said.
Most of the chimpanzees at the Limbe center belong to the most endangered subspecies of chimpanzee, inhabiting only Nigeria and adjacent parts of Cameroon, the researchers said.
In 2004, this subspecies was predicted to be extinct within 25 years if current rates of decline continued.