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Monster Fish Q & A, with Zeb Hogan

Zeb Hogan is raising awareness of freshwater fisheries by highlighting some enormous examples. (Photo courtesy of National Geographic)

Editor’s Note: Dr. Zeb Hogan is an assistant research professor at the University of Nevada-Reno, and host of the National Geographic series “Monster Fish.” Hogan is the keynote speaker at NC State’s Frederick and Joan Barkalow Distinguished Conservationist Lecture, which will be held Sept. 14 from 1:30-2:30 p.m. in David Clark Labs, Room 101. The event is free and open to the public, and will be followed by a reception from 2:30-3:30. We had a chance to talk with Dr. Hogan about enormous fish, making science accessible to the public, and what you can do to support sustainable fisheries.

The Abstract: We often hear about fisheries being imperiled, why are large freshwater fish species especially vulnerable?

Zeb Hogan: Large-bodied fish tend to be slow-growing, late-to-mature, high-value species. Many of them are also migratory or have large home ranges. All of these characteristics make large fish more vulnerable to extinction. Take sturgeon for example – females of some species don’t reproduce until they are over 20 years old; they are full of a product worth thousands of dollars (caviar); and many species must migrate long distances to spawn. These traits make sturgeon particularly susceptible to threats such as overexploitation and habitat fragmentation.

TA: Through the Megafishes Project and “Monster Fish”, you’ve dealt with some enormous fish. What is the largest fish you’ve ever encountered in the wild, and where did that take place?

ZH: That’s a tricky question: we often don’t weigh the fish, because we don’t want to hurt them. The largest obligate freshwater fish that I’ve come across during the project was a 646-pound (293 kilogram) Mekong giant catfish that was caught in northern Thailand in 2005. I’ve also seen a 15-foot-long freshwater stingray, a 12-foot-long sturgeon, and a 250-pound carp. In North America, our largest obligate freshwater fish are the alligator gar, the paddlefish and the lake sturgeon. There have also been reports of very large catfish in the U.S., but nothing over 200 pounds has been reported since the 1800s.

TA: What has been the biggest surprise to you in your travels as a researcher and host of “Monster Fish”?

ZH: I guess I am always surprised by the low profile of many species of large-bodied fish. Take the alligator gar for example: until recently, it was considered a “trash fish” by many anglers and pretty much ignored by the general public. And yet it is one of the largest freshwater fish in the world, capable of growing to over 8 feet and more than 300 pounds. The alligator gar also has a long evolutionary history, and is vulnerable to overfishing. Perhaps what I’m describing is the phrase “out of sight, out of mind.” I think it’s a shame that we often ignore the underwater world – especially in freshwater – because we can’t see it.

TA: What do you hope to accomplish through “Monster Fish”?

ZH: While I never thought I’d end up being part of a TV show, I do enjoy sharing my experiences with others. I think this is especially important with freshwater fish, because they are so difficult for people to see and appreciate. We spend a lot of time on “Monster Fish” trying to figure out interesting ways to educate people about large-bodied fish. Often, it’s a huge challenge just to find the fish, then we have to come up with a way to film the fish without hurting it, and teach people at the same time. My favorite shows have been those where we are working in clear water and we can swim or dive and viewers can see the fish behaving naturally underwater. Unfortunately those opportunities are rare, partly because the fish themselves are rare and partly because many species are found in remote areas in deep or murky water.

TA: What are the challenges in conveying scientific research to the general public?

ZH: That’s a very good question and it’s hard to answer in a few sentences. If you are referring specifically to TV and “Monster Fish,” then the challenge is conveying good science and a conservation message in an entertaining way. National Geographic Television faces the same constraints as other television channels: if people don’t watch the shows, they can’t afford to put them on air, because advertising pays for the production of the shows. So National Geographic Television is constantly trying to find a balance between programs that have a good message vs. programs that people will watch. Readers may think it is easy to find that balance but it is not.

The BBC, for example, does a very good job of finding that balance with their “Planet Earth” shows, but those programs are publically financed and have huge budgets. There are also some other very simple practical considerations: when we are filming we need to combine our research objectives with enough action to keep the programs from becoming too dry. This can be a challenge since research usually requires repetition of the same task again and again. Repetition (replication) may make for good science but it doesn’t make for good TV!

TA: What can the average person do to help support sustainable fisheries and protect these species?

ZH: There are many things the average person can do and, if everyone did just one of them, fish would be much better off! People can volunteer at their local aquarium or museum, help out at a watershed clean-up day, join an organization like National Geographic, American Rivers, or International Rivers, support local, national, and international legislation to better regulate and protect fish and their habitats, eat sustainably caught fish, be aware of invasive species issues and be supportive of efforts to control them, encourage your local schools of include freshwater issues in their lesson plans, ask your local power company or water district to hold a “freshwater day,” or just get out, take your children, your family or your friends and enjoy a day on the river or a day of fishing. Find ways to keep opportunities like that open to everyone for the future.