A red fox hunts by moving back and forth over an area, finding food by scent and sound. A red fox that is hunting a mouse can stand still and listen for it, and it can hear small animals it cannot see, such as a mouse under snow or hidden in leaves. It creeps close, the way a cat does, and then pounces: a fox that has found a mouse launches itself into the air at a 45-degree angle and lands on it, pinning it to the ground. Researchers in the Czech Republic observed 84 wild red foxes jump at small prey and recorded 592 jumps. The study found that red foxes strongly preferred to jump toward the north-east, approximately 20 degrees off from magnetic north, which is the direction a compass needle points. In short vegetation, the foxes showed no preferred jump direction. A red fox's top running speed is approximately 48 km/h (as reported), and it can jump over obstacles as high as 2 m.

Red foxes are omnivores, which means they eat both plants and animals, and they eat rodents and rabbits; voles are a favorite food of red foxes. Red foxes store extra food by hiding it, in a den or buried in the ground. Where meadow voles are common, they can make up as much as 50 percent of a red fox's diet, and where berries and fruit are plentiful, they can make up almost all of it. A red fox eats approximately half a kilogram to one kilogram of food each day; red foxes help to control the numbers of rodents and rabbits. A red fox may partly bury extra food, cover it with soil, grass, leaves or snow, and mark it with urine.

A red fox den is a hole in the earth 15 to 20 feet long, usually on the side of a knoll, and red foxes often use an old woodchuck burrow as a den instead of digging their own. A newborn red fox weighs approximately 96 g (3.4 oz) and is covered with fine gray fur. Red fox pups are born brown or gray and usually turn red within approximately a month, and they open their eyes 9 to 14 days after birth. Red foxes often leave bones, feathers or other found objects around the den entrance for the kits to play with. At 10 weeks old a kit may travel short distances from the den without a parent, and at approximately 12 weeks old the pups begin to explore their parents' home range on their own or with a parent. Red fox kits are nursed for 56 to 70 days, and their parents and older siblings also give them solid food.

In Connecticut, the normal home range for a red fox is approximately 2 to 4 square miles, in New Jersey and other temperate places red foxes typically range over 2 to 8 square miles, and in Colorado a typical home range is five to ten square miles, depending on food. How big a home range is depends on its habitat and on how much food is there, and a red fox with kits usually stays within a mile of its den while the kits are growing up. Red foxes mark their home ranges with scent, and a red fox usually stays in the same home range for life. Red foxes can disperse, or move away to a new area, as far as almost 400 km, or as near as 10 km. Male red foxes in Iowa and Illinois moved a mean of 18 miles (29 km) from where they were born, and females moved 10 miles (16 km).

Words to know

• magnetic: like a magnet
• vegetation: plants
• disperse: move away
• temperate: mild weather