Wolves have a fearsome reputation as pack hunters that are able to execute ruthlessly efficient co-ordinated attacks on much larger animals. But they would much rather go fishing.

Given the choice between traipsing miles to find a fast-moving deer or spending a day on the river, the wolves will opt for a fish dinner. Grey wolves had been known to take the occasional fish, but only recently have scientists discovered that they seek out salmon in preference to their normal fare.

Salmon are available in their thousands for several weeks during the early autumn in the Great Bear Rainforest in British Columbia, Canada, and while they are running upstream they comprise up to 70 per cent of the wolves' diet.

Dr Chris Darimont, of the University of Victoria in Canada, said that it made sense for the wolves to catch salmon instead of chasing deer. “Salmon is a safe resource in contrast to deer that could kick back and break your ribs or skull - which happens quite often with wolves.

“The fish is highly nutritious. Salmon offers a bit more protein but the real bonus is that it offers more fat. It has four times more calories bite for bite than deer.

“Wolves have a huge home range and have to search for deer. In contrast, salmon come to you. There are thousands on their way and you can sit in the estuary for a month or two.”

Whole families of wolves will take part in the fishing expeditions, and the antics of the pups trying to catch their own salmon provided the scientists watching them in the forest with welcome light relief.

He said: “We certainly see families together. It's a wonderful sight. At that time of year the pups are four to five months old. Watching them hunt together in a creek is actually a riot.

“They tip over on algae-covered rocks, they make miss after miss after miss, then they finally get one of the salmon and parade it around their siblings and parents with great pride.” To catch a fish the wolves stand perfectly still with their heads held low. When they identify a suitable salmon they dash forward and plunge their heads in the water.Puzzlingly, they ate only the heads. Researchers suspect that they have learnt to avoid the rest of the fish because of the risk of picking up parasites.

Bears and wolves can often be seen fishing near each other but the salmon are so abundant that the hunters tolerate one another. Bears have an advantage because they can hook the fish out with their claws instead of plunging their faces into the water.

In the area where the wolves were seen fishing there are few roads, little logging and hardly any people. So primitive was the forest and so important were the fish to the wolves and bears that Dr Darimont believes the sight of the two species fishing almost side by side in shallow rivers would once have been seen in Britain.

“I would have expected the association between wolves and salmon to be present in the UK population. It's like a little glimpse into the past,” he said.

The findings of a four-year study of the wolves were published in BMC Ecology.

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