Revealed: Fish DO have a good memory and can even be sneaky

Daily Mail, By DAILY MAIL REPORTER, 2nd July 2010

Fish do not have a three second memory and are in fact quite cunning, according to scientists.

Researchers found that fish remember potential predators for months. They are also capable of teamwork and carrying out acts of deception.

Dr Kevin Warburton, who has been studying fish behaviour for many years, described the suggestion of the three second memory as 'absolute rubbish'.

Fish are far cleverer than scientists have previously believed

He 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.'

Dr Warburton, whose research has focused on Australia's freshwater fish, has run experiments looking at how Silver Perch learn how to handle different types of prey.

Dr Warburton said fish also exhibit behaviour that we tend to think as human.

'Some behavioural traits that we think are very human, such as deception, fish have as well,' he said.

'Fish can recognise other individuals and modify their own behaviour after observing interactions between other individuals.

'For example Siamese fighting fish will attack other members of the same species more aggressively if they've seen them lose contests with other fighters.'

In reef environments, cleaner fish remove and eat parasites from larger 'client' fish.

Dr Warburton added: 'But 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.'

Dr Warburton said fish inspect suspected predators to assess the level of threat.

He added: 'For added safety, they often do this as co-operating pairs, with the two fish taking the lead alternately. They will approach predators most closely when they have co-operated in previous inspections.'

He said minnows recognise dangerous habitats by associating the smell of the water with 'alarm' chemicals that are released when fellow minnows are damaged by predators.

This learned response to habitat water can be socially transmitted to naive fish.

Dr Warburton is an adjunct researcher with Charles Sturt University's Institute for Land, Water and Society in Albury, New South Wales, Australia.