Red Fox

The red fox is the most successful wild carnivore on the planet, measured by sheer range. It lives above the Arctic Circle and in the Sahara’s fringes, on remote mountainsides and in the centre of London, and it manages this on a diet of almost anything and a talent for staying out of sight.

Overview

Red foxes are found across virtually the whole Northern Hemisphere and were introduced to Australia in the 1850s, where they have spread across the continent and driven several native mammals toward extinction. Their success comes down to two things: an extremely broad diet, and behavioural flexibility — a fox will change its hunting, denning, and activity patterns to fit wherever it finds itself.

Physical characteristics

Despite the bushy coat, a red fox is a lightweight animal — 3 to 7 kg, about the size of a small dog or a large cat — with a slender frame, long legs, large triangular ears, and a long tail (the “brush”) tipped with white. The classic coat is rusty red with black “socks” and ear tips and a white throat and belly, but colour varies to silver, black (“silver fox”), and a dark-cross form.

The fox’s senses are tuned for hunting small prey: it can hear a mouse squeak from 100 m and a low-frequency rustle in undergrowth from many metres away.

Hunting

Red foxes hunt like cats. A fox locates prey by sound, stalks in a crouch, and finishes with a high, arcing mouse pounce, landing with the forepaws pinning the animal.

One of the strangest findings in animal behaviour is that this pounce is aligned to a compass bearing. Foxes catch far more prey when they jump toward the north-east, and researchers believe they use a visual sense of the Earth’s magnetic field as a “rangefinder” — lining up the sound of hidden prey with a fixed magnetic reference to judge exactly how far to leap into snow or thick grass.

Foxes are also thorough scavengers and cachers, burying surplus food and returning to it later, and they will take fruit, beetles, earthworms, and household scraps in large quantities.

Behaviour and life cycle

Red foxes live in family groups centred on a breeding pair and a territory, sometimes with non-breeding adult “helpers” — usually daughters from a previous year. They are mostly active at dusk and night.

Breeding is tightly seasonal. Cubs — usually four to six — are born in early spring in an underground den. They emerge at about a month old, are weaned by two months, and disperse in the autumn, sometimes travelling tens or even hundreds of kilometres to find their own territory.

People and foxes

The red fox is listed as Least Concern and is one of the few wild carnivores whose numbers and range have grown alongside human expansion. It is legally hunted, trapped for fur, and culled as a livestock and game predator across much of its range, and it suffers periodic outbreaks of mange and rabies, but none of this dents the overall population.

Where the red fox has been introduced, however — most damagingly in Australia — it is a serious invasive species, and large sums are spent trying to control it to protect native wildlife.