CHIMPS will be arriving in Scotland to take part in a breeding programme that experts hope will boost numbers of the rarest type of the primate, The Scotsman has learned.
Western chimpanzees used to thrive in 13 countries including Nigeria and Sierra Leone, but the sub species is under threat due to habitat loss.
In a bid to help increase numbers, bosses at the Royal Zoological Society of Scotland (RZSS) are plann
ing to add about five western chimps to the Budongo Trail enclosure at Edinburgh Zoo.
It is hoped the newcomers will breed with two resident male western chimps.
David Windmill, chief executive of RZSS, said: "The western chimp is particularly endangered and we are hoping the breeding we do will contribute to a much wider, worldwide effort to maintain endangered species in captivity."
Jo Elliot, animal registrar at Edinburgh Zoo, added that the breeding programme was important to make sure all captive chimps did not become hybrids – a cross between different sub-species.
"There's a concern that if we don't do something now, we will only have hybrid chimps in captivity," she said.
"There is no immediate risk of western chimps going extinct but, if we can, we want to keep pure sub-species, which are specifically adapted to a particular region."
However, it will be touch and go whether the males will breed successfully.
One, a 47-year-old animal called Ricky that used to be a ship's mascot, has never shown any interest in mating. The other western chimp at Edinburgh Zoo has also not yet bred.
Before the new chimps arrive, the three males in the Budongo Trail that are not western chimps will have vasectomies to stop them breeding with the newcomers.
Zoo staff are anticipating ructions when the new arrivals turn up. The existing 11 chimps have been living together for at least 20 years and could be aggressive towards new additions to the group.
However, experts will use their skills to separate the animals so they meet each other one at a time, to avoid fights.
The zoo must now wait for the European Studbook Foundation, which keeps records of the chimps in zoos across the continent, to find suitable animals to be transferred to Edinburgh.
They could arrive within a month, or it could take up to a year.
Before the plans for the breeding programme could start, staff had to find out whether any of the animals in Edinburgh Zoo were western chimps.
They look no different to other sub species, and the complex process of working out their origin took about two years.
DNA samples were taken, but this only showed whether the mothers were western chimps, whereas both parents had to belong to that sub-species.
That meant paternity tests also had to be carried out. However, it was extremely difficult to work out the identity of the fathers of some of the chimps.
Zoo staff were amazed to find out bones of two of the fathers were preserved at the National Museum of Scotland, and DNA samples were taken from these.
Eventually, they worked out two of the five males in the collection were the right sub-species.
One other male and one female could be, but more tests are needed.
If the female turns out to be a western chimp, she will also be encouraged to breed. The other females in the groups will be kept on contraception so they do not breed.
