Wednesday, July 20, 2011
Did you know that a female dolphin born under the Sanibel Causeway may live for 25 years and never venture more than 15 or 20 miles from the causeway? Pretty amazing, but female Atlantic Bottlenose Dolphins have perfected the art of blooming where they are planted. Wouldn’t it be great if we could all do that as well?
Last week during "Dolphin Daze," campers from the Sanibel Sea School studied how dolphins use biosonar – echolocation — to "see" the world around them.
Dolphins produce sound waves with the assistance of the melon, a fatty organ located in their forehead that is believed to help them focus the sound waves used for echolocation. The shape of the large rounded forehead of dolphins comes from the underlying melon gland.
To demonstrate to ourselves our echolocation works, we had a rousing game of “Echo Location,” Sanibel Sea School’s rendition of Marco Polo, only where the one who is "it" wears a blacked-out snorkeling mask and thus cannot peak.
We also learned that dolphins have a voice apart from their echolocation. They use their voice to produce a variety of clicks and whistles through which they communicate to one another. Each dolphin has a signature voice used to distinguish individuals in their social groups – these social groups are called pods.
Back in camp, we made drums from cast off large food cans and saw how each of us can create a signature ‘voice’ distinguishable from the others in the pod.
With drums at hand, we held a drumming circle and talked about the difference between noise and music, but it was unclear whether we succeeded at the latter rather than the former.
We spent time learning to throw a cast net and gained a better appreciation for the challenges a dolphin faces to capture their daily ration of nearly 25 pounds of fish. We played cooperative hunting games, frolicked in the warm Gulf waters and pretended we were dolphins while learning to surf – dolphins are perhaps the world’s best surfers.
Sanibel Marina donated a fun-filled cruise on the Stars & Stripes for all of our campers, where we were treated to the spectacular sights of dolphins surfing in the wake. It was a great way to have a close encounter of the dolphin kind.
We are grateful to the many people who help create life-long ocean experiences and memories at Sanibel Sea School. Bailey’s General Store quenched our thirst with an unending supply of ice, and The Island Cow provided hamburgers and hot dogs for our Friday cookouts. The Bait Box donated nets, expertise and island skills to our programs. The Sanibel Community House hosts our milk and cookies on Friday afternoons, where we share our week of fun with parents and grandparents.
Sanibel Sea School is a Sanibel-based non-profit foundation; we envision a world where all people value, understand and care for the ocean. Please share our vision by joining us at sanibelseashool.org.DINA CRAIG