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Three-second fish memory 'a myth'

Fish can remember things for months, according to researchers who have dismissed the myth that the animals have a three-second memory.

The traditional view that fish lack the brain power to retain memories is "absolute rubbish" said Dr Kevin Warburton, an adjunct researcher with Charles Sturt University's Institute for Land, Water and Society in Australia.

He made his conclusions after studying the behaviour of Australian freshwater fish such as the silver perch, which can remember a predator for several months after only one encounter.

Dr Warburton said: "Fish are quite sophisticated.

"Fish can remember prey types for months. They can learn to avoid predators after being attacked once and they retain this memory for several months.

"And carp that have been caught by fishers avoid hooks for at least a year.

"That fish have only a three second memory is just rubbish."

Nobody knows where the three-second myth comes from.

Dr Ashley Ward, a fish biologist at Sydney University, said: "It seems to come from an advert many years ago, but nobody is sure what it was for."

Fish can also learn to improve how to catch food, said Dr Warburton, carry out acts of deception and modify their behaviour.

For example, in reef environments cleaner fish who eat parasites off 'client' fish act on best behaviour when they spot a larger patron.

Dr Warburton said: "What's fascinating is that they co-operate more with clients when they are being observed by other potential clients.

"This improves their 'image' and their chances of attracting clients.

"Some cleaners co-operate with small clients to raise their image so as to deceive larger clients, which they then cheat on by biting them rather than removing their parasites."

© Telegraph.co.uk