[Post 4] European wildcat and domestic cat hybrids

European wildcat and domestic cat hybrids

Introgressive hybridization is an issue for European wildcat conservation. Hybrids between the European wildcat (Felis silvestris silvestris) and domestic cat (Felis catus) are commonly found in Scotland and Hungary. Domestic cats were historically spread across the globe by humans and are found in most regions that humans inhabit. Therefore, wildcat-domestic cat hybridisation is likely to have been facilitated by humans. 

When two species hybridise, the offspring has a mixture of genes from each species. When fertile hybrid offspring are produced, the more that they breed with each other and the common species, the more likely it is for the rarer species population to reduce in its genetic diversity. The amount of the original genes in a species is called the ‘genetic integrity’. For example, a purebred wildcat would have 100% genetic integrity. The genetic integrity of the wildcat is declining due to ‘genetic pollution’ from domestic cats. The dilution of the original wildcat genes can and has led to the extinction of some wildcat populations. 

The conservation of the wildcat, particularly in Scotland, is an issue. Domestic cats are almost ubiquitous, therefore some cross breeding between the two species will inevitably occur. Conservation management within the UK must decide whether to conserve hybrids or only wildcat purebreds. With a dwindling population size, due to habitat loss, conservation of wild hybrids perhaps should be considered. Current conservation measures are based around captive breeding programs using zoo populations and the reintroduction of these individuals into the wild. However, even some of these captive populations are ‘polluted’ with domestic cat genes. The conservation management of this hybridization is proving very difficult. 

A method of identifying a European wildcat markings on the back and tail.  Fur around the mouth should always be brown in this species. Spotted markings are usually an indication of hybridisation with the domestic cat. The above images are of a taxidermy mounted European wildcat from the World Museum, Liverpool.