what is the average weight of a red fox
Red fox Red foxes are the largest species of the genus Vulpes.[37] However, relative to dimensions, red foxes are much lighter than similarly sized dogs of the genus Canis. Their limb bones, for example, weigh 30 percent less per unit area of bone than expected for similarly sized dogs.[38] They display significant individual, sexual, age and geographical variation in size. On average, adults measure 35–50 cm (14–20 in) high at the shoulder and 45–90 cm (18–35 in) in body length with tails measuring 30–55.5 cm (11.8–21.9 in). The ears measure 7.7–12.5 cm (3–5 in) and the hind feet 12–18.5 cm (5–7 in). Weights range from 2.2–14 kg (5–31 lb), with vixens typically weighing 15–20% less than males.[39][40] Adult red foxes have skulls measuring 129–167 mm (5.1–6.6 in), while those of vixens measure 128–159 mm (5.0–6.3 in).[6] The forefoot print measures 60 mm (2.4 in) in length and 45 mm (1.8 in) in width, while the hind foot print measures 55 mm (2.2 in) long and 38 mm (1.5 in) wide. They trot at a speed of 6–13 km/h (4–8 mph), and have a maximum running speed of 50 km/h (30 mph). They have a stride of 25–35 cm (9.8–13.8 in) when walking at a normal pace.[38]:36 North American red foxes are generally lightly built, with comparatively long bodies for their mass and have a high degree of sexual dimorphism. British red foxes are heavily built, but short, while continental European red foxes are closer to the general average among red fox populations.[41] The largest red fox on record in Great Britain was a 17.2 kg (38 lb), 1.4-metre (4 ft 7 in) long male, killed in Aberdeenshire, Scotland, in early 2012.[42]
Red fox Red foxes colonised the North American continent in two waves: during or before the Illinoian glaciation, and during the Wisconsinan glaciation.[17] Gene mapping demonstrates that red foxes in North America have been isolated from their Old World counterparts for over 400,000 years, thus raising the possibility that speciation has occurred, and that the previous binomial name of Vulpes fulva may be valid.[18] In the far north, red fox fossils have been found in Sangamonian deposits in the Fairbanks District and Medicine Hat. Fossils dating from the Wisconsian are present in 25 sites in Arkansas, California, Colorado, Idaho, Missouri, New Mexico, Tennessee, Texas, Virginia, and Wyoming. Although they ranged far south during the Wisconsinan, the onset of warm conditions shrank their range toward the north, and have only recently reclaimed their former American ranges because of human-induced environmental changes.[5] Genetic testing indicates two distinct red fox refugia exist in North America, which have been separated since the Wisconsinan. The northern (or boreal) refugium occurs in Alaska and western Canada, and consists of the large subspecies V. v. alascensis, V. v. abietorum, V. v. regalis, and V. v. rubricosa. The southern (or montane) refugium occurs in the subalpine parklands and alpine meadows of the Rocky Mountains, the Cascade Range, and Sierra Nevada. It encompasses the subspecies V. v. macroura, V. v. cascadensis, and V. v. necator. The latter clade has been separated from all other red fox populations since the last glacial maximum, and may possess unique ecological or physiological adaptations.[17]