Sometimes called the treefox, the shortlegged grey fox is noted for its ability to climb trees much more than other foxes. Up to 27 in. head and bodylength and 15 lb  weight, the greyfox has a bushy tail up to 17 in. long.  The general colour of the fur is grey with underpartswhite but there  is a rusty tinge along the sides of the neck, lower flanks and underside of the tail.  There is a black line along the middle of the back, continuing along the tail, and black lines on the face.  There is a noticeable ridge of stiff hairs along the top of the tail. Its size and colour vary from one region to another.  In the northeast of its range its coat is a dark grey; in the southwest it is paler and slightly redder.
    The range from southern Canada through the United States to Mexico, Central America and northern South America.  A smaller animal with shorter ears living on certain islands Off southern Calfornia is regarded as a second species. It scavenges the beaches and makes its den among the cacti.

Climbing fox

    Grey foxes live in forests, especially of southern pines, or brush country in the dry areas of the southwestern United States and Mexico.  It is difficult to assess numbers because the animal is not only about mainly at night but is also adept at keeping out of sight at all times.  It is therefore comparatively seldom seen and even its yapping bark often passes unrecognized, even if heard, partly because it is somewhat like the call of the coyote.  During the day it rests in thick vegetation or among rocks, or in a tree hollow.  Much of its food is caught on the ground but the fox will not only go up into trees when pursued but will also do so of its own will, especially to find fruits in season.  It will run up a leaning trunk or climb a straight trunk gripping it with its forelimbs and pushing upwards with the hindfeet, the long claws on the toes of the hindfeet acting as climbing irons.  Once in the tree it may leap from one branch to another.  In descending the fox backs down the tree. it is not a fast runner, nor can it run long distances.  The difference between the crude climbing of the red fox and the skill of the grey fox can best be illustrated by an accident.  A grey fox was found dead in a tree its tail caught by the tip in a forked twig and further held by having passed through a second fork.  From the scarring on the bark of the nearby twigs the fox had made desperate efforts to free itself.  The important point is that all the twigs around the fox were no more than 3/4 in. thick and most were nearer 2/5 in. 

Fox and grapes

    Its diet is wide and takes in mice, squirrels, small birds and eggs, as well as insects.  It also includes more plant food than is usual in the dog family.Grain and fruits, especially wild grapes and wild cherries, form tlhe bulk of the food at certain seasons and in particular areas.  With such a wide diet the grey fox readily takes to farmland and can be a nuisance, especially where there is poultry.  It is also established in some builtup areas, for instance, the outskirts of New York City.  The actual requirements of grey foxes were worked out by Richard F Dyson, Curator of Large Mammals at the Arizona-Sonora Desert Museum at Tucson.  Because some of the mammals were overweight and had shaggy coats he tested grey foxes for 6 months and found they kept in excellent health on 3-8% of their own body weight of food (flesh and fruit) per day. Later it was shown that this held good for other carnivores. 

United families

    The cubs are born in spring after a gestation period of about 2 months, the litter averaging 3 or 4, but it may be from 2 to 7. At birth the cubs are black, blind and helpless, about 31 oz weight.  They are weaned at 6 weeks.  The male helps in bringing up the family, the cubs finally leaving the parents at the age of 5 months.  Grey foxes have lived up to 12 years in captivity. 
    The grey fox may be killed by wolf, coyote, bobcat and lynx but today its main enemy is man.  Because of its habit of going quickly to ground or up into trees it is not hunted but trapped.  In this the trapper takes advantage of the regularity with which a grey fox uses a run through the vegetation and sets his traps accordingly.  The pelts make only second-rate furs. 

Dogs do climb

    But for its habit of tree-climbing the grey fox would hardly be noticed by zoologists.  Yet tree-climbing foxes are no novelty, even among those whose coats are red.  Many a fox has outwitted the hunt by running up the trunk of a leaning tree and hiding among the foliage.  Others have ascended by using low branches but at least one red fox in England denned up in the crotch of a large tree and had her cubs there.  The crotch was 15 ft from the ground and the vixen reached it, judging by the scratch marks on the bark, by jumping up from buttress root and scrabbling the last few feet. This is highly unusual, but ordinary tree-climbing by red foxes seems to be common than we suppose.  One thing they never do is cling by the forelegs, as the grey fox does.  That is a cat-like action, bit it probably also a result of the grey fox's short legs.  Domestic dogs will sometimes climb trees.  Those that do this most successfully are the small breeds with short legs.