By Graham Keeley in Barcelona
Published: 16 March 2007
Pet cats are to provide an unexpected lifeline for the world's most endangered feline, the Iberian lynx.
Researchers in Spain discovered that they can inseminate the eggs of domestic cats with the sperm of male lynx. The breakthrough means they can test the fertility of males' sperm and widen the gene pool of the rarest wild cat.
Experts believe that there are only between 100 and 150 Iberian lynxes alive, due to dwindling habitats and a decline in their natural prey, wild rabbits.
The only two colonies of wild lynx where breeding pairs have been found are in the Doñana natural park and in the Sierra Morena, both in Andalucia, southern Spain.
Lynx are often killed by cars. But now scientists are to extract sperm from males killed on the roads, and freeze it for later use.
They have been helped by veterinary practices near Madrid, which contributed the ovaries of dead domestic cats. These gave scientists a pool of immature eggs which are then nurtured in laboratories and later fertilised with lynx sperm.
Scientists can then see how suitable sperm is for impregnating female lynx. Using domestic cat eggs means researchers do not have to use the eggs from an already endangered species. It means they do not have to move lynx from one location to another, avoiding problems with transport and adaptation.
Eduardo Roldan, who led the project at the Superior Scientific Research Council, said: "We know the case of one male Iberian lynx that has not been able to successfully breed, although lab tests with domestic cat eggs show that he is fertile.
"Cases such as this one can help develop a proper reproduction programme." The research will be presented at the Field Biology and Research Conference in Oxford in September.
Another project which researchers hope will save the Iberian lynx from extinction involves releasing domestic rabbits into the wild as a food supplement in the Doñana natural park.
At present, dwindling numbers of wild rabbits have forced hungry lynxes to stray from their natural habitat in search of prey.
Francisco Palomares, head of the lynx project at the Doñana park biological station, hopes this will stop the lynx from leaving the park - into the path of passing motorists - to find food.
Mr Palomares said: "They will not eat dead meat, so there is no point in putting out slaughtered rabbits. We will use domestic rabbits and release them into the wild. If there are few rabbits, female [lynx] cannot eat properly nor feed their cubs properly."
Scientists believe if lynx numbers continue to fall at their current rate, they will be extinct in 10 years.
They estimate as much as 35 per cent of the remaining population have now left the park in search of their favourite dish.
The Iberian lynx was once found throughout Spain, Portugal and parts of southern France, with an estimated population at the turn of the century of 100,000. But years of over-hunting and the loss of natural habitat to make way of agriculture caused the population to drop dramatically to just a few thousand by the 1980s.
In Spain, the fight to save the Iberian lynx has become a political battle. Ecologists were last year accused of faking sightings of the timid feline to stop a planned motorway near Madrid from being built. But environmental groups claim the lynx will become the "first big cat to die out since the sabre-toothed tiger". They have urged the Spanish government to do more to ensure the lynx is not lost.