Basking shark's incredible 3000-mile journey


A basking shark has shocked experts by making an amazing 3000-mile journey from Ireland to Africa.

The 5m/16' long female shark named Banda, was one of five tagged by the Irish Basking Shark Study Group last July, while she was feeding in waters off Ireland.

She lost her tag in December when she was just off the coast of Africa, 3000 miles away.

Some scientists had begun to wonder whether Basking sharks were travelling further afield than previously thought. A number of years ago, Dr Simon Berrow, a co-founder of the study group, had been tagging sharks off Malin Head when he noticed that many carried a parasite found on whales and dolphins that have travelled through tropical waters.

"Up until now there have been lots of different theories put forward about the sharks and one was that they hibernated over the winter because there wasn't enough food in the waters around the north Atlantic," said Emmett Johnston, project co-ordinator.

"Other people said they went offshore and they have been tracked offshore in the winter.

"But we have been theorising that they head further south to where the food is, like the larger whales from this area."

But another mystery is what food these sharks are eating when they head south.

Mr Johnston explained that their main food - plankton - is not found in the tropical waters there.

"It is a very different kind of habitat - it is akin to finding a polar bear in the desert," he said.

"It is in stark contrast to the type of waters that they are associated with.

"Recovering five complete basking shark tracks will allow us to compare the data and make informed conclusions. Until then, there is not much we can say other than this is a highly unusual place to find a species that is presumed to inhabit temperate waters."

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