Wild bears getting fat on fast food diet

Wild bears living near US towns and cities are growing overweight from eating the left-overs of fast food meals, researchers have found.

High-calorie, high-fat diets have led to record levels of obesity among people and even domestic pets in the US.

Now, a study in Nevada has found that black bears living near urban areas are picking up the poor eating habits of their human neighbours.

Bears that wander into populated areas to scavenge for food were also found to be less active than those in the wilderness, according to the Wildlife Conservation Society (WCS).

Dr Jon Beckmann and Dr Joel Berger of the WCS said many black bears no longer bothered hunting for food in their wild habitats.

Instead, the constant supply of high-calorie fast food found in rubbish bins proved an easier way for the animals to get year-round sustenance.

The researchers used radio collars to track the movement of 59 bears in the Lake Tahoe basin on the California-Nevada border.

They found that the animals fell into two distinct groups.

One group, dubbed “country bears”, spent nearly all their time in the wild.

The second group, “city bears”, virtually lived in urban areas and feasted on the rubbish and left-over food of local people.

A bear fattening up for winter needs a massive 20,000 calories a day.

While country bears spent more than 13 hours a day looking for food their lazier cousins in the city spent just over eight hours feasting on human left-overs.

Come winter, country bears spent more time in their dens, avoiding the cold and lack of food outside.

But city bears took advantage of the year-round supply of left-overs and kept on eating, the study found.

The end result was that the city-dwelling animals were fatter than the average bear.

A quarter weighed over 400lbs, compared to an average of 220lbs-300lbs. Some weighed between 500lb and 600lbs.

It is not clear whether the bears’ health suffered as a result of their excess weight.

But as more bears wander into, or live in, towns and cities, the more likely they are to come into contact with humans.

Many are hit by cars and killed, and the dangers of a city mean more bears are dying than being born in some areas, the study said.