Dive Dry with Dr. Bill

#321 A Whale... of a Shark!

I was in Atlanta over the holidays to enjoy the Bushing family's first holiday reunion in some 10 years. Mom flew in from Florida and sister Judy from Michigan to join sister Nancy, her family and me in Georgia. Of course it was wonderful to be able to spend time together even though it meant staying "high and dry" for three weeks. My nephew David, an avid diver himself, thought a trip to the Georgia Aquarium would be a great way to make me feel "at home" so the two of us drove into the city for a day at this much touted facility.

The Georgia Aquarium is the largest in the world. It houses more than 500 species of aquatic life. One attraction I was very interested in seeing was the huge tank that houses three whale sharks, a manta ray and probably thousands of other interesting fish. I've had concerns about keeping whale sharks in captivity, especially since two died in captivity during 2007 at this aquarium. I have even greater concerns about keeping marine mammals such as dolphins and small whales like the white belugas in such facilities since they are usually highly social and sentient beings. I've always thought how we humans will feel once the Xanadusians invade planet Earth and imprison us in cages for their entertainment and "education." Of course I am also greatly discomforted knowing that the Xanadusian diet may well include human flesh. At least we do not eat the whale sharks, mantas or beluga whales held captive in aquaria.

David and I walked through every exhibit hall in the aquarium. I saw many of the species I've encountered on my dive trips to the tropical waters of SE Asia, Australia, the South Pacific and the Caribbean. They even had a tank or two dedicated to our own kelp forest critters... complete with garibaldi. But there was no question that the massive 6.3 million gallon tank housing the whale sharks and manta ray was the show stopper. David and I spent much of our visit staring through the thick acrylic at the many species of fish swimming in that tank, but mostly the magnificent whale sharks. This is the only aquarium outside of Asia that exhibits them.

The aquarium has a program whereby SCUBA divers can submerge in the tank to directly experience the whale sharks for $290. However, given the state of my "economy," this was not an option. The only time I've dived in waters where a whale shark had been sighted was while diving Chumphon Pinnacle off Koh Tao, Thailand, in the Gulf of Siam. Unfortunately my team did a deep dive to the base of the pinnacle. It wasn't until we returned to the dive boat that we learned the other divers in the shallow water above 40 feet had an encounter with a whale shark. Just my luck. The same thing happened the one time a manta ray was sighted on a dive.

Whale sharks are the largest fish in the world, reaching lengths up to 46 feet and a weight of 33,000 pounds. I felt I came pretty close to that eating all the holiday cookies Mom and my sisters baked. These fish are found in all tropical and subtropical waters, usually out in open water near the surface. The enormous head is dominated by a huge mouth up to five feet wide, but has two tiny eyes. The fish's dorsal surface is gray to blue-gray in color, with a network of white vertical and horizontal stripes and many white spots. The underbelly is white, as is the case with many counter-shaded fish. When seen from above the darker upper surface blends in with the darker deep water. From below the white belly nearly matches the bright sky. You don't have to worry about offending these fish since they are very "thick skinned" (up to four inches).

Although these huge sharks dwarf even the great white, they are nothing to be feared... unless they happen to bump into you underwater! Despite their huge size, their food is taken in very tiny bites... but LOTS of them. Whale sharks feed not on marine mammals or even large fish, but mostly on plankton. That is why they need the huge mouths. However, in doing the research for this column I learned that they will also swallow large numbers of baitfish and can even take an occasional tuna (sushi on the fly). You learn something new every day! Oh, I also learned they don't become sexually mature until age 30. I'm glad I'm not a whale shark!

I greatly enjoyed the opportunity to see the whale sharks as well as the manta rays and beluga whales. However, my concerns about keeping such large fish, and especially intelligent mammals, in relatively small aquaria were not entirely satisfied. I will readily admit that there is great educational value in allowing the many school aged children (and their parents!) to see these and other species. Certainly holding them in tanks has allowed a lot of scientific research on their physiology and health that would be much more difficult tasks to undertake on them in the wild. However, just keep in mind what will happen to us when the Xanadusians finally arrive. Maybe if we released the Willies and whale sharks in our tanks, the little chartreuse men would look more kindly on us. I said maybe. No guarantee.

© 2009 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!

(Top) Whale shark swimming in the aquarium's main tank; (bottom) beluga whale
peeking at us and manta ray swimming past.

This document maintained by Dr. Bill Bushing.
Material and images © 2008 Star Thrower Educational Multimedia