Monday, March 2, 2009

When is a Red Fox, Not a Red Fox?


When it’s a black fox, a cross fox, a silver fox, a bastard fox or a Samson fox. The name "Red Fox" does not begin to describe all the colours found in the species. As a result the red fox is often referred to as the coloured fox, or polytypic: having many representatives.
The red fox can have several possible colour schemes, some of which may occur in the same litter. There are three recognized colour phases: red, silver and cross, and two naturally occurring mutations: bastard and Samson.
Between 45 and 75 percent of foxes are considered red phase. Red phase foxes may be found in much of North America but the silver and cross are seldom found south of Canada. The mutations are usually found in Canada.
The silver phase, which makes up between 2 and 17 percent of red foxes, may be black or silver depending on the amount of silver-tipped hairs which occur. Silver foxes are black except for a white tip on the tail and a silver frosting on the tips of some or nearly all the guard hairs.
The third phase, the cross fox, (about 35 percent of all red foxes) is dark with light buffy patches near the legs, shoulders and hips, and a distinct cross of dark fur across the shoulders.
The bastard fox is described as a cross fox with a red streak down the back rather than a dark one. This mutation may be the offspring of red and silver parents. The second mutation, often referred to as the Samson, lacks guard hairs and has only short underfur giving the animals a wooly appearance. The Samson is usually sooty gray in colour.
The genetics of coat colour in red foxes is very complicated. Variation within families may occur but in the wild only the three basic colour phases are present. Selective breeding of ranch foxes has resulted in some unusual colour phases, and changes in in temperament (more people friendly) and the adrenal glands.
Red foxes molt once a year beginning in April, triggered by the lengthening of days, and by June most foxes look rather ragged. However, the new fur coat begins to grow during summer and is most brilliant during October and November. But by mid-January the wear and tear of survival depletes the guard hairs, leaving only the soft underfur.
The rabies prevention program initiated by the Ministry of Natural Resources has resulted in an increase in fox numbers. This may provide more opportunities to see members of the multi-coloured red fox.
Photos by Clayton Rollins

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