Do Guppies Have a Memory?

Imagine that while peering into your guppy tank, you notice some semblance of strange behavior from your guppy, almost as if he recognizes you. Even if that is not how you came across this article (although that would’ve been cool), we still have the answers for you! Do guppies really have memory?

Guppies do have memory. Guppies have been known to remember and recognize other fish and have even been shown to possess learning retention. In addition, guppies can successfully complete mazes and even remember which of their counterparts were better competitors.

Memory is complex in nature, and other factors such as learning and recognition play a role in memory. Let’s explore these factors and how they relate to one of our favorite tropical fish – the guppy.

Can Guppies Remember?

I know we have all been bombarded from time to time with ‘facts’ about fish retaining 5-second memory-spans and lovable cartoon fish characters who are on the forgetful side. So it would be easy to think that guppies would be in a similar boat.

But, in fact, this is far from the truth. Guppies (among other fish) are capable of some impressive intellectual feats. Some feats can be likened to other mammals such as mice and rats.

Guppies do have memory and are even capable of remembering and recognizing other fish. Additionally, guppies show the ability to learn as they can complete mazes successfully. They can even remember which of their counterparts were better competitors.

Although not specific to the guppy itself, some studies have shown that different fish species can recall information up to weeks or even months later. One popular aquarium fish species has even been shown to remember information for up to 5 months later.

That is an astounding degree of information recall. Especially considering most people are likely to forget where they have placed their car keys in the morning – guilty as charged.

Regardless, it is clear that different fish species have varying yet impressive memory spans; Meaning your guppy may remember things for longer than you think.

Swimming Guppy

Are Guppies Smart?

As it turns out, yes! Although it is very easy to assume that guppies may not be one of the sharpest tools in the shed, the guppy can perform some pretty impressive intellectual tasks.

It all has to do with the brain size of the guppy – go figure. Research has shown that large-brained female guppies were able to outperform smaller-brained female guppies in numerical tasks.

And those numerical tasks mentioned earlier? Guppies were even shown to be able to count!

Guppies with strongly lateralized brains were able to distinguish between three and four objects. Lateralized brains refer to the distinction between the left and right brain that executes different cognitive functions.

Those that had non-lateralized brains were only able to differentiate two versus three objects. This being said, regardless of the degree of brain lateralization, counting is an impressive feat for any animal – let alone a guppy!

It is not entirely known why guppies would need to achieve such a task as counting. But one theory states it all boils down to survival. For instance, when faced with predatory threats, guppies need to be able to choose the largest shoal and join that shoal. This is due to the fact there is safety in numbers.

Can Guppies Recognize Their Owners?

This answer is not as clear-cut as the others as there is a lack of studies around this question. The answer is…possibly.

One fascinating study showed that a specific species of tropical fish could remember and recognize human faces with a surprising degree of accuracy – up to 86%!

Even more interesting is that the fish reached the accuracy level of 86% even when the scientists tried to make recognizing the faces harder for the fish.

As the study was based on showing photos of human faces to the fish, the scientists changed the picture’s color to black and white and distorted the head shape on the images. In fact, the guppies reached the highest level of recognition accuracy after the scientist distorted the faces.

Similarly, many guppy owners are convinced that their pet guppy recognizes them. So, although anecdotal, there may just be some truth to this behavior.

So when you are peering into your tank and watching your beloved guppies, consider that they might just be watching you too!

How Long Is The Attention Span Of A Guppy?

Now the other aspect to discuss is ‘how long is the attention span of the guppy?’. A quick Google search reveals quite a few articles detailing that the memory span of guppies consists of about 15 seconds.

This information is usually coupled with stats covering the average attention span of a human and goldfish, stating that the average human attention span is now less than that of a goldfish and guppy – yikes.

However, take the stats mentioned above with a grain of salt. Although this is widely spread all over Google, many people argue that the original source of the statistics, and credentials of the study, are shaky at best.

Because, although a well-known company released the stats, it is argued that the company used statistics from a not-so-trustworthy site. In addition, there seems to be no supporting literature supporting this claim.

So although there is no clear answer supported by other literature, it is clear that guppies can hold a fair amount of attention – at least enough to count, complete mazes, and take note of how their other fellow fish look like.


Memory is a complex thing, and it is clear that we still have a lot to learn about the memory capacity of the guppy. However, the guppy’s ability to complete intellectual tasks proves that it is brighter than many would have given credit.

Also, keep in mind that your guppy may just recognize and remember things for longer than you think – so maybe this is reason enough to put down that extra piece of chocolate.