By Dr. Becker
If a standard goldfish is given quality food, clean, toxin free water, and ample room to grow and swim, he can live up to 30 years. So when the owner of George, a 10-year-old standard goldfish, noticed a tumor on his head, she decided to take action.
The tumor had grown quite large, making it difficult for George to swim and eat properly. So an Australian veterinarian performed a high-risk microsurgery to remove the tumor; it was George's only hope for survival… and it was a success.
The team put the fish under general anesthetic (first by letting George swim in a bucket that contained anesthetic-laced water and later by pumping it via a tube over his gills). After the tumor was removed, George recuperated in a bucket of oxygenized water for a few days, and he is now fully recovered.
While this type of operation might sound unusual, the Australian veterinarian had done similar surgery 10 other times… and as he noted, veterinarians do not "discriminate between the species when trying to save lives." Not only do I whole heartedly agree that all life is valuable, but it's so refreshing to meet people who are committed to finding vets who are able to help, regardless of their economic "value," as in George's case.
Do Fish Feel Pain?
There's an ongoing debate over whether or not fish feel pain, but if you're wondering whether anesthesia is necessary for a fish surgery, there's accumulating research suggesting it certainly is.
In 2003, researchers found 58 receptors in the heads of rainbow trout that responded to electrical and chemical shocks. The fish also rubbed their lips into the gravel and against the sides of their tank, while their ventilation rate increased nearly double after the shocks.
What's more, when the fish were given morphine, their pain-related behaviors were significantly reduced, as was their ventilation rate. The researchers concluded that "these pain-related behaviors are not simple reflexes and therefore there is the potential for pain perception in fish."1
Dr. Culum Brown, a professor in the Department of Biological Sciences at Macquarie University, has stated that pain perception is deep rooted in vertebrates since it is essential to animal survival. And not only does he believe it's obvious that fish feel pain, he also lead a newly published study that showed fish may have significant cognitive abilities, too.
New Study: Fish Are Intelligent, Deserve Compassion
According to Dr. Brown, fish perception and cognitive abilities match or exceed that of other vertebrates. In a review published in Animal Cognition,2 he shows evidence that fish:3
- Perform multiple complex tasks simultaneously (a trait that was once believed to exist only among humans)
- Recall the location of objects using "feature cues" (which humans figure out how to do around age 6)
- Have excellent long-term memories
- "Cooperate with one another and show signs of Machiavellian intelligence such as cooperation and reconciliation"
- Use tools
Given his decades of research, Dr. Brown believes fish should be afforded the same level of compassion and welfare as warm-blooded vertebrates, but unfortunately most view them only as food or pets (and as pets, they are often not given the same level of care as dogs, cats, or birds). He writes:
"Part of the problem is the large gap between people's perception of fish intelligence and the scientific reality. This is an important issue because public perception guides government policy. The perception of an animal's intelligence often drives our decision whether or not to include them in our moral circle.
From a welfare perspective, most researchers would suggest that if an animal is sentient, then it can most likely suffer and should therefore be offered some form of formal protection.
…Although scientists cannot provide a definitive answer on the level of consciousness for any non-human vertebrate, the extensive evidence of fish behavioral and cognitive sophistication and pain perception suggests that the best practice would be to lend fish the same level of protection as any other vertebrate."
Fish Become Angry if Forced to Live in Small, Barren Spaces
Adding to the accumulating evidence that fish deserve better treatment is research from 2011 suggested that Midas Cichlid, a common aquarium fish, show behavioral changes depending on their living environment.
Fish living in large aquariums with complex (i.e. stimulating) habitat were significantly less aggressive than those living in smaller barren spaces.4 The fish living in cramped, uninspired quarters showed mild disgust by flaring their fins, and displayed more significant anger by chasing, nipping, charging, and even killing one another.
Similar behavior has been observed in sea urchins and great white sharks held captive in small environments. Clearly, some fish become aggressive when placed in confined spaces, and that aggression can wreak havoc on the lives of other fish of the same species sharing the same environment, not to mention, if Dr. Brown's research is correct, on their own psyche.
Do You Want to Hear Fish 'Talk'?
Fish don't talk like you and I do, of course, but that doesn't mean they don't communicate. Some fish "talk" by grating their teeth, blowing bubbles, rattling their bones, or clacking their jaws.
Others use their swim bladders to make vibrations in the water that create sounds such as booms, growls, thumps, whistles, and even musical notes, which are detected by other fish. The vibrations may communicate mating or spawning information, or may be used to avoid predators, or for reasons we have yet to uncover. You can hear some fish sounds for yourself using the New York Times links below:
- Fish sounds, part 1: Clownfish, toad fish, herring, cusk eel, black drum
- Fish sounds, part 2: Silver perch, weakfish, spotted sea trout, red drum, Atlantic croaker, oyster toadfish, striped cusk eel
Tips for Keeping Your Pet Fish Happy
Unfortunately, many people think of fish as a "throwaway" pet that requires little investment of time or money. In reality, you should put careful consideration into planning the best environment for whatever type of pet you choose, and consider them to be worthy of attention and medical care.
Many small aquariums, and especially fish bowls, do not provide optimal welfare for fish, particularly if you don't add in stimuli. Larger aquariums with a complex habitat will help to create more natural behavior and, likely, greater well-being in your fish. This includes:
- Providing ample space – at least 24 square inches of water for every one inch of fish
- Providing a quiet pump and filter that keeps water clean and flowing
- Installing an air pump for oxygen and a thermometer to monitor water temperature (this should generally be between 68 and 76°F but depends on the species of fish)
- Providing items for your fish to explore – plants, rocks, structures, ceramic objects, etc. It's important to make sure the "furniture" you add to your fish tank is non-toxic
- Keeping your fish in a quiet area away from loud televisions and radios, and out of direct sunlight
- Providing the right type of food for the species of fish (fish may vary in their nutritional requirements)
- Cleaning the tank regularly and using pure water (most tap water contains fluoride, chlorine, and impurities that can harm fish)
- Taking care not to startle your fish with sudden changes in lighting or noise
- If your fish seems sick, take him to a fish vet along with a sample of tank water
- While some fish do better alone, most enjoy companionship and should be kept in pairs (or more)
Finally, when choosing fish for your tank, only buy fish that have been bred in captivity, not those taken from the ocean.