For years, fish have been unfairly labelled as living decorations, supposedly doomed to swim in circles and forget everything within seconds. But science tells a very different story – some of these clever little swimmers can even recognise faces and be trained to perform tasks. So, let’s dive into some more facts about fish.
Modern research reveals that fish are intelligent, trainable creatures capable of learning complex behaviours and remembering information for months. A recent Companion Animals NZ survey found that around 5% of New Zealand households keep fish as pets, with the main motivations being relaxation, decoration, and a sense of familiarity.
Health and wellness benefits
The calming effect of watching fish isn't just anecdotal. Scientific studies have demonstrated that viewing fish can reduce blood pressure and heart rate, making aquariums a legitimate form of stress relief in our fast-paced world.
For anyone feeling stressed, aquariums can provide a calming focal point. The gentle movement of fish, the sound of flowing water, and the living ecosystem create conditions that promote relaxation and reduce stress.
The benefits extend beyond general relaxation. Research has shown that exposure to brightly coloured aquariums can increase appetite in individuals with Alzheimer’s disease and reduce disruptive behaviours among residents in specialised dementia units, suggesting that keeping fish may have therapeutic benefits in medical care settings, too.
Practical advantages for modern living
Fish thrive in settings that would be unsuitable for other animals, particularly small apartments where space is at a premium. They don't require walks in bad weather, won't scratch furniture, and won't disturb neighbours with noise.
For families with children, fish are safe and contained, non-destructive, and relatively affordable to keep. They’re also ideal for people with allergies who can’t live comfortably with furry animals.
Caring for fish can teach children responsibility through regular routines like feeding, water testing, and tank cleaning. However, adults should always be the main caregivers, and families should think carefully before taking on this responsibility – as fish are not completely low-maintenance companions.
They require attentive care, including regular water testing, correct filtration, temperature and pH, adequate space, appropriate feeding and environmental enrichment to stay healthy and happy. Each species has unique needs - some grow very large or live for decades - so keeping fish takes time, education and sometimes veterinary support.
The SPCA has an excellent kids’ guide to fish care available here: https://www.spca.nz/advice-and-welfare/article/caring-for-fish
Debunking the memory myth
The long-standing myth that fish have only a three-second memory has been thoroughly disproven by modern research. Studies show that fish can remember information for months or even years - for example, anecdotal evidence shows that goldfish have been observed recalling the colour of a feeding tube a year later. Fish demonstrate complex spatial learning abilities, forming cognitive maps of their environment and navigating using multiple landmarks. They possess hippocampus-like brain structures that support spatial cognition.
Fish are surprisingly good at predicting the timing of events. Like most animals, they use environmental cues alongside their internal clocks to predict when things will happen. This ability helps them anticipate daily events such as prey movements or predator activity. They can even combine timing and location in what’s known as “time–place learning” - the skill of knowing not just when but also where something is likely to occur.
What's particularly fascinating is that fish show individual variation in their learning abilities. Different fish display varying levels of cognitive flexibility. Just like people, some fish are quick learners while others need more time and patience.
Target training and fish
Target training is a technique for teaching fish specific behaviours, akin to teaching a dog to "sit." By guiding fish to touch a designated target, trainers can direct them through hoops, around obstacles, or to specific locations. This method is widely utilised in aquariums to manage feeding times, facilitate medical procedures, and reduce stress during veterinary care. Training also provides mental stimulation and environmental enrichment, enhancing overall fish wellbeing.
Ethical considerations and modern fish keeping
As our understanding of fish intelligence has grown, so too has scrutiny of older fishkeeping practices like tiny tanks, solitary housing for social species, lack of enrichment, and poor handling during transport and sales.
Recognition of fish as sentient beings with complex cognitive abilities demands that we reconsider outdated practices. Fortunately, progressive scientists and aquarists are leading a shift toward better practices. Environmental enrichment, species-specific setups, and positive reinforcement training are now recognised as essential components of proper fish care. Target training and other interactive behaviours aren't just entertainment - they provide crucial mental stimulation that improves overall welfare.
This modern approach to fishkeeping acknowledges that meeting basic survival needs isn't enough. Fish, like all intelligent animals, benefit from cognitive challenges, social interaction (when appropriate for their species), and environments that allow them to express natural behaviours.
More than decorations: Giving fish a Good Life
Fish may not wag their tails or curl up on the couch, but they’re no less fascinating or deserving of care. As our understanding deepens, it’s clear that fish are thinking, feeling creatures capable of learning, remembering, and thriving when given the right environment. By moving beyond outdated ideas and embracing evidence-based care, fish keepers can offer their pets a life that’s not just comfortable — but truly enriching.
References:
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