Red Fox (Vulpes vulpes)|
Image: Wikipedia, Minette Layne
Image: Wikipedia, Quartl
|Note: V. lagopus is often placed in a separate genus (Alopex), but van Gelter argued that they should be treated as congeneric because they hybridize. American red foxes (also called silver foxes) are often treated separately as V. fulva, but are here lumped under V. vulpes with European red foxes. Image: Wikipedia, Quartl|
Contact between these foxes occurs in northern North America and northern Eurasia. The cross, which has been produced in captivity, is reversible, but in most crosses the mother is an arctic fox. Natural hybrids have also been reported (see below).
These hybrids are generally intermediate in appearance, but grow faster, and are larger, stronger, and more vicious than either parent. They bark like Arctic foxes. Hybrids have white banding on their guard hairs, a genetically dominant trait characteristic of V. vulpes.
There are conflicting reports concerning the fertility of hybrids. Some authors say they are sterile in both sexes (e.g., Mäkinen and Gustavsson 1982; Nes et al. 1988), others that females are partially fertile. According to Lohi (1982) the Golden Island breed was a mutation that “appeared in 1980 at a farm in Finland in the progeny of a white arctic fox (Alopex lagopus) female mated with a silver fox (Vulpes vulpes) male [Silver Fox is an alternative common name of V. vulpes]. Further matings at the same farm have produced 100% Golden Island offspring.” For this new breed to be established, certainly at least some of the hybrids must have been partially fertile.
Hybrids are created by breeders because they have the short, wooly underfur of V. lagopus with the large body size of V. vulpes. In addition, F₁ litters are larger than those from pure V. vulpes matings.
Gudmundsson (1945) reports an escaped red fox vixen whelping a litter in Iceland with a native arctic fox male.
By the same author: Handbook of Avian Hybrids of the World, Oxford University Press (2006).
References: Anonymous 1929, 1930; Boettger 1896; Cole and Shackelford 1946†; Gustavsson et al. 1988; Mäkinen and Gustavsson 1982†; Nes et al. 1988; Nyberg 1980; Pomytko et al. 1973; Serov and Zakijan 1977; Serov et al. 1976; Switonski 1982; van Gelder 1977b (p. 10), 1978 (p. 7); Wipf and Shackelford 1949.
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