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Species of the month

Island Fox

Some facts about this small caniform carnivoran:

Size: The Island Fox is the smallest fox in North America, significantly smaller than the Gray Fox (Urocyon cinereoargenteus, i.e. the only other member of the Urocyon genus). It is also slightly smaller than the Swift Fox (Vulpes velox) and Kit Fox (Vulpes macrotis). Typically, the head-and-body length is 48–50 cm (19–19.5 in), shoulder height 12–15 cm (4.5–6 in). The tail is 11–29 cm (4.5–11.5 in) long, which is notably shorter than the 27–44 cm (10.5–17.5 in) tail of the Gray Fox.
Distribution: Contrary to the widely spread mainland Gray Fox, this species is endemic to six of the eight Channel Islands of California, United States.
Protection status: IUCN: Urocyon littoralis (Baird, 1857) (Near Threatened). Last assessed by Coonan, T., Ralls, K., Hudgens, B., Cypher, B. & Boser, C. in July 23, 2013. There are several active conservation measures in place in order to help support the species. In 2013 only 4,001 mature specimen remained, but the population is increasing and now the annual survival rates are above 85%.
Etymology: The generic name Urocyon means "tailed dog", from Greek ουρά meaning 'tail' and ancient Greek κύων meaning 'dog'; because of the tail which according to Baird has "a concealed mane of stiff hairs, without any soft fur intermixed". Its specific name is the Latin word littoralis meaning 'of the seashore'.

An interesting phylogenetic detail about the Island Fox – or rather, the genus Urocyon – is that whole genome sequencing (WGS) indicates that it is the most basal genus of all living canids. Fossils of their ancestors found in Kansas date to the Upper Pliocene (circa 2.6–3.6 million years ago), with some undescribed specimens dating even older. See Lindblad-Toh, K. et al. 2005. Genome sequence, comparative analysis and haplotype structure of the domestic dog. Nature 438: 803–819. DOI: 10.1038/nature04338