Are fish forgetful? Find out if this common belief about their memory is true.
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"You have the memory of a fish!" Is a common phrase (and insult!) we have all heard, implying the target has a poor memory. But where did this phrase come from, and is it actually true?
Do fish have bad memories?
It is true that fish have relatively small brains compared to most other vertebrate animals (animals with spines), and this is often assumed to be linked to a supposedly low intelligence level.
However, this assumption is not correct. Despite differences in brain size and form, fish have been scientifically proven to have memories lasting months, perhaps even years, as well as the ability to recognise and consciously avoid pain and danger, seek out reward, navigate mazes, and even use tools.
While fish have a brain structure that is different from humans, it is not true that this means they are incapable of forming memories. Fish do not have a hippocampus, the brain structure in mammals that forms memories, but they do have an analogous structure called the lateral pallium. Research has shown that this is responsible for the connection of events at different points in time, which allows fish to form connections between events and experiences, thus remembering things and acting accordingly.
Do goldfish have a three second memory?
This particular claim, despite its notoriety, is a complete myth and scientifically unfounded.
Science has actually found goldfish to have quite impressive memories. They are able to remember where in their tank they are usually fed, can correlate a particular action to a reward, can escape nets and navigate mazes, and remember other individual goldfish, even after long periods of separation.
Research that shows fishes have good memories
Research from scientists in Canada suggests that fish can remember things for up to twelve days, forming associations and learning contexts.
They studied African Cichlids, a species often found in aquariums, and they trained the fish to enter a particular zone of the aquarium to receive a food reward. Each training session lasted twenty minutes, and the fish were trained for three days. After three days, they were not given training for another twelve days. They were then reintroduced to the training aquarium, and their movements were tracked.
The scientists found that the fish demonstrated a clear preference for the area they had previously associated with the food reward, demonstrating their memory abilities.
Cleaner Wrasse have been widely studied, due to their unusual relationships with other fish. They provide cleaning services to other fish, which has been proven to form complex social relationships. Cleaner Wrasse often provide this 'service' to fish who would normally prey on them, but the provision of this service overrides this natural instinct. They have also been proven to recognise over 100 different ‘client fish', and show preference for some clients over others.
This proves they have an ability to not only remember individual fish, but also to form relationships and discern between individuals. They are only four inches long, with a brain that weighs less than a tenth of a gram, but brain size does not prevent them from displaying some amazing cognitive abilities.
Other studies have found memory retention in wild fish up to eleven months after a negative experience, and several experiments have proven that fish are able to learn to escape mazes. Fish have also been witnessed using tools to carry out every day actions; National Geographic has published photographic evidence of fish using rocks to open the hard exterior of shellfish to get to the soft meat inside.
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The impact of these myths on fishes
Myths such as these make it easier for us to devalue animals and their experiences. This makes it easier to believe other falsehoods, such as 'fish can’t feel pain' or ‘fish don’t think’, and conclude that they do not need to be provided protections.
However, fish are conscious beings who can suffer and they currently suffer in greater numbers than any other vertebrate animal, as they are not only farmed in the greatest numbers but also experience serious welfare issues including disease, sea lice, and overcrowding on these farms.
This makes it all the more shocking that the UK Governments currently grant fewer legal protections to farmed fish when compared to land animals.
FISH ARE FORGOTTEN, NOT FORGETFUL
The science shows that fish cannot be said to be any more forgetful than any other animal. They have highly developed brains and sensory systems, which allows them to form long-term memories, maintain complex social relationships, avoid danger, and use tools. In fact, their cognitive abilities may even exceed those of other animals in some areas.
Although science clearly shows that fish have good memories and are able to feel pain, they are currently denied some important basic protections in UK law.
It’s a legal requirement in the UK for animals, including fish, to “be spared any avoidable pain, distress or suffering during their killing and related operations.” But, while other farmed animals are protected by detailed legislation around how they must be slaughtered to spare avoidable suffering, fish are not.
As a result, the welfare of the 77 million farmed fish slaughtered in the UK each year is not being properly protected. Investigations on UK fish farms have revealed salmon cruelly having their gills cut while fully conscious, and being repeatedly clubbed to death.
That’s why we launched our Forgotten Fish campaign calling on the UK Governments to give fish the same protections at slaughter as other farmed animals.
HOW YOU CAN HELP FISH
Sign this petition which calls on the UK government to give fish the same protection as other farmed animals.
Note: Why 'fish' and not 'fishes'? In his book ‘What a Fish Knows’, ethologist Jonathan Balcombe points out that referring to their plural as ‘fish’ lumps them together ‘like rows of insentient corn.’ But the truth is that fishes are individuals with personalities, relationships and the capacity to feel. The Humane League UK wants to set an example of recognition and inclusion in the language that we use as well as fighting to improve the rights of fishes farmed for food. We advocate for using the plural ‘fishes’ instead of ‘fish.’ For the purposes of this article, we have used the more commonly-used ‘fish'.