This article is part of our Pets special section, dedicated to scientists' growing interest 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 caring for dogs and cats, or horses, or exotic animals at the zoo. Jessie Sanders came to veterinary school with a more particular passion. “I was that weird fish kid,” she said.
It was an interest that surprised even her. In college, Dr. Sanders began volunteering at an aquarium, hoping to work with whales. Instead, she found herself assigned to the fish team, and fell head over heels in love with her finned charges.
“I love fish,” he said. “I love the way they're built. I love the way they interact with their environment. And there's so much we don't know about all the little inner workings.”
Today, Dr. Sanders runs Aquatic Veterinary Services, with patients that include carnival goldfish, pet store bettas, and prized koi worth tens of thousands of dollars. Last year, she became one of the first 10 veterinarians to receive a board certification in fish practice, an entirely new accreditation.
Dr. Sanders spoke to The New York Times about her life as a fish veterinarian. Her story is based on two conversations, and her responses have been edited and condensed.
I've had nothing but pet fish for 10 years, and it's been amazing and challenging. I love the challenge of setting everything up in an underwater environment. And the amount of personality you get in the fish – they have so many little quirks. Some of them are super laid back and gentle, 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 adjacent wall, and they liked to play their music all night. Fish have an organ known as a lateral line that picks up vibrations; that's how they can sense predators, swimming together in a school. Obviously, having rock music playing at all hours of the night is very stressful. Everything that was attached to that wall was lost within the first month of being open.
We just have a mobile office now. We serve the greater San Francisco Bay Area. I’ll drive three to eight hours a day. When I get there, it’s like taking your cat or dog to the vet. We’ll talk about it: What happened? Did they eat? Is there anything in particular you want me to take a closer 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 their overall health. If you're breathing nothing but pollution, you're going to be prone to more disease. So let's check the water chemistry; if it's terrible, the fish are already stressed. I don't want to mess with that because that could make things worse.
Then you have to catch the fish. I have a bunch of different nets. The cute little square aquarium nets for tank fish: I usually use one on each side of the fish and squeeze them together. In the bigger ponds, I use drag nets. They have floats on top and weights on the bottom. I have ponds so big I have to use two nets and get in there with my waders. It’s one of those things you have to practice. Nobody’s good at it at first, but now I’m really good at it.
After I catch them, I transfer them to the examination tank. I usually have a tank with their tank or their pond water ready to go with some sedatives. For most of my physical exams, I like to have the fish lightly anesthetized. It's less stressful for them; trying to hold onto a wet, slippery catfish isn't going to be exactly in our favor. We just need them to be manageable. So they might move a fin at me, but once they're anesthetized, I can get a really good look at their entire body.
We will usually do skin mucus and gill biopsies. The skin mucus biopsy is mostly just to look for parasites, which can irritate the fish and make them lethargic. Gill biopsies are more important because they can show us how their respiratory system is working. They give us a great diagnostic tool without having to stick a tube down their throat.
If we need to do more diagnostics, ultrasounds or x-rays, we can do it while the fish is sleeping. A client has a goldfish pond, and there is one that couldn't get up and swim with all the fish; he got stuck at the bottom. We'll do some x-rays.
A buoyancy disorder occurs when a fish, which should be able to swim in the center of the water column, sinks to the bottom or floats at the surface. For fish with buoyancy disorders, it is very important to be able to evaluate their internal anatomy, particularly the swim bladder, a small air sac that helps them float.
It can also be related to diet. It is very common in goldfish ponds where there are fish that float after eating. If there is a lot of competition and limited food during the meal, it is crazy. They are all eating, eating, eating; they are sucking in a little too much air.
This can be corrected by spreading out the food a bit more or by feeding a sinking diet. Many fish diets float because it gives the owners the opportunity to evaluate them at the surface, and of course it is much more interactive. Koi and goldfish are naturally bottom feeders. But we have trained them, because they are golden retrievers, they will do anything for food, to come to the surface during feeding time.
For fish surgeries, there are a lot of different levels. I do a lot of enucleations, which are eyeball removals. In fish, they are so easy; they don’t have eyelids or need any kind of eyeball to look normal. I did one for a little goldfish that actually had an abscess in his eye. The fish was just miserable. We were able to get it out and the next day the owner is like, “That’s a completely different fish. He’s eating, he’s moving fast.” They just heal beautifully every single time.
We see ovarian cancer very commonly in koi. If we catch it early enough, we can do surgery to remove it. We use a higher dose of sedative. We have a specialized feeder where the fish sit upright. They sit over a small tank that contains anesthetized water. There is an aquarium pump that pumps it through a tube up to the fish's mouth, over the gills, down the side of the body, and back to the tank.
The biggest challenge is that the public doesn't even know that fish vets exist. Even within our profession, we are ridiculed. Fish are not respected as pets in general. Like, “Why are you wasting your time? It's just a fish.” To many people, it's not just a fish. It's a real living, breathing animal that needs care and respect. Many fish are brought into homes as training pets and are treated really poorly.