FORTUNE — It’s tough enough to keep a room of people happy with the office thermostat, imagine catering to the thermal (and all other) needs of 500 different species. Brent Whitaker is responsible for the more than 12,000 animals — and the 100 or so people who take care of them — at the National Aquarium’s two facilities.
Whitaker worked his way up to the job of “deputy executive director of biological programs” at the aquarium in Baltimore, but he started out as an aquatic veterinarian, a job that he and a group of his contemporaries pioneered.
Whitaker has spent the past 22 years leaning how to maintain his staff and funding while also minding the seemingly unusual health needs of rare species. He talks to Fortune about dreaming of a job that didn’t yet exist, how to keep the salt mix right in the shark tank, and making a scientific celebrity out of a sperm whale named “Inky.”
Fortune: What is the most interesting thing you’ve learned from managing so many animals?
Brent Whitaker: Life is a balance for them. By that I mean you could have a two- or three-degree temperature fluctuation because your heater goes off and suddenly you have a parasitic outbreak in a large reef tank.
So you talk about managing people, you have to look at the same kind of things for animals to meet your goals. But you’re not looking at salaries; you’re looking at providing the proper diet, the proper temperature, and the proper humidity.
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This is all an investment that goes into creating a great visitor experience with animals that live, because that ultimately is more affordable than the old model in place when this building was first built, back in the early 80s. The concept was: bring an animal in; the animal dies; go replace it.
That doesn’t sound sustainable.
There were no veterinarians there. I was the first full-time veterinarian in an aquarium anywhere, and I joined in 1989. They had part-time vets. Basically, if you were a fish keeper you knew what medicine to put in your tank. It was a different level of practice, if you will.
So how did you get interested in a field that pretty much didn’t exist?
I saw the aquarium when I was in college and fell in love with it. I always wanted to be a veterinarian but I also wanted to be a marine biologist or an oceanographer, and I wanted to figure out how to make these two things work together.
I finished college and I didn’t have the grades to go to vet school, so I went to the University of Florida for a masters in aquatic toxicology. By my second year, I applied to veterinary school and they didn’t let me in. So I went in and asked them why, and they said, ‘Well, you want to be an aquatic animal veterinarian, and we’re in the business of putting people out there who are going to get jobs, and there aren’t jobs doing this.’”
I thought about that as I was driving home, and I was really disturbed. So I stopped by the pet store on the way home and asked them for all their sick fish. I went back to school and dissected the fish and told the store which drugs they could use to keep the fish healthy based on the findings. The next year, they let me into vet school.
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And really, I got out and couldn’t find a job working with aquatic animals.
Oh no, they were right!
I actually ended up in private practice out in Florida for just about a year when the job at the National Aquarium opened up. As I said, it was the first full-time staff vet that any aquarium had opened.
What was the biggest challenge you faced?
When I started, they were having difficultly keeping the sharks alive in the large ocean tank, which is connected to the fish tank, and then the fish started dying. So we started looking at them, and I was really struck by the fact that all these fish had no parasites. Usually, in an established, healthy system, you see some sort of parasite.
The other thing is, we would go to another facility to replace the shark and that animal would die within 24 to 48 hours. That told me something was majorly wrong with the environment.
It turned out they had an imbalance of salt in the water. It cost about $30,000 in just salt, the balance was so bad, but we had great success, the animals did great, the parasites came back. More importantly, it set the tone for how we prevent it in the future.
The needs of these animals seem so complicated. Is it difficult to find experts who understand such rare animals?
It depends. We’re right now looking for a jellyfish expert, and we’ve identified a few, but they’re harder to find than, say, a reptile expert.
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I would imagine they’re also more difficult poster children than a cuter animal like a dolphin.
We’re doing a lot of work with dolphins right now and how we present them to the public. We don’t have shows anymore; we have “presentations.” But I still need to do the jump because I need to capture your attention and I understand that because I too am amazed. You look at it and you go, “Wow, 600 pounds of pure muscle just propelling itself 20 feet in the air.”
What are some of the most memorable things you’ve learned about animals?
We took care of a pygmy sperm whale through our rescue program a number of years ago, and we published a number of papers once we released it. This is a deep-dwelling animal. We learned about a little organism that this animal had that nobody had published before. We learned that this animal had a belly full of plastic and debris. It was a great “Smoky the Bear,” if you will; it was “Inky the Pygmy Sperm Whale.”