This article is part of our special pets section on the growing interest of scientists in our animal companions.
Many students enter veterinary school with career aspirations that date back to childhood, when they fell in love with the idea of serving cats and dogs, or horses, or the exotic animals at the zoo. Jessie Sanders arrived at vet school with a more specific passion. “I was the odd little fish,” he said.
It was an interest that had surprised even her. In college, Dr. Sanders had begun volunteering at an aquarium, hoping to work with whales. Instead, she found herself assigned to the fish squad – and falling hard for her finned charges.
“I just love fish,” he said. “I love the way they are made. I like the way they interact with the environment. And there’s still so much we just don’t know about all the little inner workings.”
Dr. Sanders is running today Aquatic Veterinary Services, with patients that include carnival goldfish, pet store bettas, and prize-winning koi worth tens of thousands of dollars. Last year, he became one of the first 10 veterinarians to become board certified in the practice of fish, an entirely new accreditation.
Dr. Sanders spoke to The New York Times about life as a fish veterinarian. Her story was based on two conversations and her responses edited and condensed.
I’ve done nothing but pet fish for 10 years, and it’s been awesome and challenging. I like the challenge of putting everything in an underwater environment. And the number of personalities you get in fish – they have so many little quirks. Some of them are super chill and nice, and some of them are absolute terrors.
We had a hospital for about three years. Unfortunately a 24 hour gym moved in and shared the wall next door and they liked to play their music all night. Fish have an organ known as a lateral line that detects vibrations. is how predators can sense, swim in a school together. Obviously, having rock music playing at you all hours of the night is very stressful. We lost everything connected to that wall within the first month they were open.
We just have a mobile clinic now. We serve the greater San Francisco Bay Area. I will drive between three and eight hours a day. When I get there, it’s the same as taking your cat or dog to the vet. We’re going to have a conversation: What’s going on? Have they eaten? Is there anything in particular you want me to take a very close look at?
The most common “disease” we see in fish is actually poor water chemistry. Like the air we breathe, the water a fish swims in is critical to its overall health. If you breathe nothing but pollution, you will be prone to more diseases. So we check the water chemistry. if it’s terrible, the fish are already stressed. I don’t want to lay a hand on them because that could make things worse.
Then you have to catch the fish. I have a bunch of different nets. The cute little square fish tank nets – I usually use one on each side of the fish and squish them together. In larger ponds I use mesh nets. They have floats on top and weights on the bottom. I have ponds that are so big that I have to use two nets and get in there with my waders. It’s one of those things you have to practice. No one is good at starting out, but I’m pretty good at it now.
After I catch them, they will be transferred to the exam tub. I usually have a tub of their tank or pond water ready to go with some tranquilizers. For most of my physical examinations, I prefer the fish to be lightly anesthetized. It’s less stressful for them. Trying to contain a wet, slippery torpedo won’t really be to our advantage. We just need them to be manageable. So they might wave a fin at me, but once they’re stunned, I can get a really good look at their whole body.
We are usually going to do skin and gill mucus biopsies. The skin mucus biopsy mainly looks for parasites, which can irritate the fish and make them lethargic. Gill biopsies are more important because this can show us what their respiratory system is doing. It gives us a great diagnostic tool without having to stick a tube down their throat.
If we need to do more diagnostics, ultrasound or x-rays, we can do it while the fish is asleep. A client has a goldfish pond, and there is one goldfish that just couldn’t get up and swim with everyone. it’s kind of stuck at the bottom. We’ll take x-rays.
A buoyancy disorder is when a fish that should be able to swim in the middle of the water column either sinks to the bottom or floats on the surface. It is very important for fish with buoyancy disorders to be able to assess their internal anatomy — specifically the swim bladder, a small air sac that helps them float.
It can also be related to diet. This is very common in goldfish ponds where you have fish that float around after eating. If there is a lot of competition and limited food during feeding time, it is madness. Everyone eat, eat, eat. they absorb a little too much air.
This can be remedied by spreading the feeding out a bit more or feeding a sinking diet. Many fish diets float because it gives owners a chance to evaluate them on the surface, and obviously it’s much more interactive. Koi and goldfish are natural bottom feeding fish. But we have taught them – because they are golden retrievers, they will do anything for food – to surface during feeding.
For fish operations, there are many different levels. I do a lot of enucleations, which are removals of the eyeball. In fish, these are so easy. they have no eyelids or need to have some kind of globe to look normal. I made one for a little goldfish that actually had an abscess in her eye. The fish was just miserable. We managed to get it out, and the next day the owner says, “It’s a completely different fish. He eats, he zips.” They heal beautifully every time.
We see ovarian cancer very often in koi. If we catch it early enough, we can have surgery to remove it. We use a higher dose of the sedative. We have a specialized trough in which the fish sit upright. They are sitting on top of a small tank that has the stunned water. There is an aquarium pump that pumps it through a tube into the fish’s mouth, goes over their gills, runs down the side of their body, and then back into the tank.
The biggest challenge is that the public doesn’t even know fish vets exist. Even in our own profession, we are ridiculed. Fish are generally not respected as pets. Like, “Why are you wasting your time? It’s just a fish.” For many people, it’s not just a fish. It is a real, living, breathing animal that needs care and respect. Many fish are brought into homes as practice pets and get the short end of the stick.