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Explorer of the Week: Samuel “Doc” Gruber

We are pleased to announced that this week’s explorer is Samuel “Doc” Gruber, a shark expert who received funding from National Geographic in 2009 for his research on adult lemon sharks. As owner and director of the Bimini Biological Field Station located in Bimini, Bahamas, Gruber offers marine biology internships to people interested in shark research. He is a recognized...

We are pleased to announced that this week’s explorer is Samuel “Doc” Gruber, a shark expert who received funding from National Geographic in 2009 for his research on adult lemon sharks. As owner and director of the Bimini Biological Field Station located in Bimini, Bahamas, Gruber offers marine biology internships to people interested in shark research. He is a recognized authority of shark behavior and created the World Conservation Union’s (IUCN) Shark Specialist Group. In our correspondence, after he sent many, many photos, some of which you see below, I remarked “WOW!  What an amazing life you are leading!”  He replied by telling me he is a survivor of stage III non-Hodgkin’s lymphoma, has learned to never give up, and feels like one of the luckiest people in the world. 

Photo: Gruber kisses a lemon shark at the Sharklab in Miami, FL
Photograph by James Barley

If you could trade places with one explorer at National Geographic, who would it be and why?
Tell you the truth I have never wanted to do anything other than what I do. So I never even considered changing places. I think Bob Ballard and Sylvia Earle are cool. I know and admire David Doubilet and have worked with a number of NGTV producers who are great guys. But I have little interest in doing anything else but teaching the up-and-coming students who want to use sharks as models for their research.

What do you think National Geographic explorers will be exploring in a hundred years?
I think they will still be exploring this planet and especially the seas. But I am hoping that we will also be exploring the cosmos too. Wish I could be here to see it!

Photograph by James Barley

What’s the biggest surprise you’ve discovered in your work or in the field?
When I was a graduate student in the early sixties my boss put me on a project dealing with vision in sharks. The prevailing theories then painted a picture of a relatable blind, bumbling creature, basically a swimming nose. I spent 15 years researching vision in these amazing creatures and discovered that they have among the most sophisticated, advanced visual systems in the sea. The eye of the shark possesses unique structures and capabilities. This work was in complete disagreement with the literature from the generations before my time. While researching their vision I used Pavlov’s classical conditioning paradigm to try to teach young lemon sharks to respond to a visual stimulus. In that way I could literally ask them questions about what they were seeing. I was totally amazed and gobsmacked when I saw the rapidity with which they learned the classically conditioned nictitating response. Dr. Niel Schneiderman and I published an article in 1975 showing that a lemon shark can learn 80 times faster than a cat or rabbit using the same training paradigm. So it was a double surprise—lemon sharks are very quick learners with their relatively big brains, and they have a really advanced visual system as well.

See Gruber feed a baby shark by hand:

Have you ever been lost? How did you get found?
While we were spearfishing off Miami in the late fifties our boat slipped anchor and floated away. We were miles off shore and had full gear on. We could just see the boat on the horizon and started swimming for it. But it just got farther and farther away. We were despairing because it was a weekday and few boaters were out. The weather turned nasty and we really got worried. Those were the days before BCDs [Buoyancy Control Device] and even backpacks, so we couldn’t stop for fear of losing our precious gear. As the afternoon wore on we headed west, figuring we would get back at some point. Then a miracle: A boat came by and picked us up. They had seen our skiff floating free and searched for us. All was well as it ended well for me and my spearing partner, Dr. Tony Pelicane. We even got our boat back.

What are you reading?
Right now I am reading Bluenoser Tales by Capt. Robert “Punchy” Powell and I love it. Captain Powell was a World War II ace in the ETO [European Theater of Operations] with over a hundred missions in his Thunderbolt and Mustang fighters … and he just turned 91. I am a fanatic for World War II airmen and aircraft. I was already seven years old when the skies were filled with dueling gladiators, and they were my heroes. I had the honor and pleasure of meeting this unique pilot, who is as sharp today as he was 60 years ago. And I am reading his story.

Photograph by William Parks

What is your favorite food?
Saba shioyaki (Scomber scomber) because it is healthy, economical, and delicious.

What are you listening to?
Right now I am listening to NPR, [including] All Things Considered, and Radio Mozart. NPR keeps me in the loop with a variety of news and stories. Radio Mozart is all the music I need.

What one item do you always have with you?
Hate to say it but my “fairly” smart phone. In the field I always carry my Leatherman Wave tool too.

If you were to meet your eight-year-old self, what would you say? 
That’s easy: Follow your dreams, don’t stop, and focus … stay with it.

If you won the lottery, what would you buy? Where would you travel?
I [would] support my research station at Bimini in the Bahamas with a new solar-operated, hurricane-proof facility and not have to worry about where my next grant is coming from—indeed, where the groceries are coming from to feed all 18 of my staff and volunteers. I [would] buy a great research vessel, a better 1957 Porsche Speedster, and a Curtiss P40 Tomahawk Flying Tiger.

If you were a baseball player, and you came up to bat, what song would be played as your “signature song”?
Strange—are there signature songs? I must have been undersea and missed that one. So I have no idea what they are for but will take a guess at “Off We Go Into the Wild Blue Yonder” (the U.S. Army Air Corps song).

Listen to Gruber’s signature song:

Do you have a hidden talent?
Hmmm … I was a semiprofessional ballet dancer. My dreams included becoming a pilot in the Air force or becoming a professional ballet dancer. In the end, I chose shark research, but I did qualify for cadet training and had danced semi-professionally based on my many years of springboard diving.

Photograph courtesy Samuel Gruber

What is your favorite National Geographic photo?
I just love this photograph by Brian Skerry from the Bahamas, in the “Eden for Sharks,” gallery showing yours truly holding a baby lemon shark in tonic immobility, a state induced by inverting a shark.

What is your favorite National Geographic magazine or news article?
The 1967 article by Dr. Eugenie Clark [that] I believe was called “Sharks: Magnificent and Misunderstood”

If you were to bring back one species of animal that has gone extinct, what would it be? 
Easy—the baddest of all, Carcharocles (Carcharodon) megalodon


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Meet the Author

Amy Bucci
Amy Bucci is a web producer for National Geographic. Her projects mainly cover National Geographic explorers, grantees and initiatives.