Sperm donors courted for big cats
Zoos called on to supply tiger and leopard lifelines.
Conservationists in London have appealed to fellow zoo-keepers for sperm donations from their big cats. They aim to create a sperm bank to keep the threatened species afloat.
The initiative's organizers hope the bank will provide a lifeline for the Amur leopard (Panthera pardus orientalis), Amur tiger (also called the Siberian tiger or Panthera tigris altaica) and the Sumatran tiger (Panthera tigris sumatrae). Stored sperm samples from the three species could create a valuable buffer against the failure of natural breeding programmes.
"This will be an extra brick in the wall against extinction," says Sarah Christie, a big-cat expert with the Zoological Society of London who is spearheading the project.
That wall needs all the fortification it can muster. Experts estimate that there are no more than 500 Sumatran tigers, 400 Amur tigers and barely 30 Amur leopards left in the wild. Many zoos and conservation groups are trying frantically to boost captive numbers to safeguard the species' futures.
The use of stored sperm is not meant to replace more traditional breeding methods, Christie says. But it could come in handy if two cats cannot be mated for logistical or personal reasons. And if a particularly valuable male dies, a sperm sample would allow him to carry on fathering kittens from beyond the grave.
To date, big-cat breeding programmes have not given us many test tube kittens. Although success rates in cheetahs are now good, only two Amur tigers have been born by this method, and not a single Amur leopard.
But results are set to improve, says Christie. And it therefore makes sense to be armed with as many sperm samples as she can get.
Christie has called on zoos in Britain and Europe to let her know whenever they are planning to anaesthetize one of their tigers or leopards. One of the London team will then hurry to the scene to take a sample from the sleeping male.
Christie says that the travel expenses, and problems with permits for long-distance sperm shipping, will prevent her from casting the net any wider. But she hopes that in time the project will become a valuable “genetic lifeboat” for the cats.
To that end, Christie plans to keep the scheme running indefinitely to collect as much sperm as possible. "We are not expecting it all to flood in over the next few months," she says.