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Dolphin Watch
The attitudes behind the aerials
By ANN WEAVER
Article published on Thursday, March 6, 2008
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![[Image]](/content_images/030608_out-01.jpg) |
| Photo by ANN WEAVER |
| A bottlenose dolphin explodes out of the water one spectacular August morning using behavior called a bow. Bows are one of three aerial behaviors. The other two are long jumps (leaps) and landing flatly with lots of splash (breaches). |
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Why do dolphins jump out of the water? Are they showing off?
Last Sunday was gorgeous. Around sunset, boats packed John’s Pass. Some were returning from a rocking day on the Gulf. Others were heading out to watch the sunset. A congenial cocktail party crowded a small square pier. Dolphins darted and disappeared just beyond.
Suddenly, right off the pier, two dolphins did a magnificent double bow, criss-crossing in midair. The cocktail crowd shrieked.
Again the dolphins bowed. Each time, the crowd roared. Wow! What a show!
The beautiful double bow by the cocktail crowd was, of course, no Sea World show for people. It was a show of attitude for other dolphins. As lovely as they are, double bows actually mean trouble and often a fight. The lovely sunset display was no exception. This fight that involved bull Rum and females Slight, Slightwin, DD1 and Face was short-lived. Maybe young Rum was out-gunned.
How do dolphins fight with aerial behaviors?
Like a World War II dog fight. You can zoom out of the water to avoid unwanted attention. Scrapefin bowed repeatedly one November evening to fend off amorous bull DD2; it wasn’t the only time. Key did the same in July to fend off bull N. N of course didn’t take no for an answer.
A dolphin can turn the tables and use aerial maneuvers to promote unwanted attention as well. At Chicago’s Brookfield Zoo, an amorous bull used aerials to intimidate the lady of his choice by landing on or near her. This crude but universal message is not limited to dolphins.
Dolphins mostly use aerial behavior to talk to each other. But they sometimes use it to talk to people too (and not just about sex). My first lesson in how a dolphin can use aerial behavior for precise communication came, fittingly, the first time I rode a dolphin tour boat. Jammed shoulder-to-shoulder, we tourists gawked for a glimpse of dolphins in a pea-green lagoon.
As dolphins do, they mostly appeared and vanished.
Then one surfaced. In a blink, I was soaking wet. I gasped. The people next to me laughed.
They could afford to. They weren’t wet. Impossibly, deftly, that dolphin had soaked only me. I should’ve known it was a sign.
My second lesson in the attitudes behind the aerials came from SeaWorld San Diego. We were collecting data with focal animal samples, which meant focusing on one dolphin at a time and ignoring everyone else in the pool. Dutifully, I disregarded the gleaming black pilot whale, twice the length of the dolphins, who cruised in front of me as I stood at the pool’s edge.
That wasn’t working for the whale.
So it breached. Breaches make big splashes. I was soaked again. Icy water hit my arms. But warm water hit my stomach. The whale had urinated on me! Talk about attitude!
Sometimes we make dolphin aerial behavior more mystifying than it probably is. In July 2006, P was searching for breakfast. Calf PC danced nearby. Assistant Marie Dahlberg and I were approaching slowly when P shot out of the water, bowed off our bow and slid back to the brine without a splash. We backed away. She resumed her hunt. But when she resumed it nearby, it was hard to believe her bow meant ‘get lost.’ It probably meant ‘good morning.’
No live wire (some dolphins are; Bet is prone to aerial behavior), P has nonetheless retrieved our waning attention with aerial behaviors many times.
Once, dolphins moved though a narrow passage to a popular bay. They split into two subgroups. As we passed P to follow the others, she breached three times. We stopped. She swung by the boat and then headed opposite of the other dolphins. We followed guardedly. She swam slower and slower until we were abreast. Then she swam off our bow as if that was the whole idea.
Another time, P poked around dim sunset waters. Mostly out of view, she was (frankly) uninteresting. As we pulled away, P switched gears. She started tossing horsetails with vigor. Attracted, we stayed to watch. Wouldn’t be the first time the animal was smarter.
Dolphins leap when they recognize something. The First Lady of dolphin training, Karen Pryor reported that dolphins leapt with glee when they finally ‘got’ the point of a training exercise. Similarly, last April guests Amanda Heidemann and Becky Sherwin were treated to repeated aerials when Bet flung herself before us so often, everyone got a couple of pictures. None of the other dolphins did that. Bet was the only one we hadn’t seen for awhile.
Sometimes, aerials aren’t about communicating with other dolphins or people. At sea, a perplexing aerial is when a calf throws itself skyward out of context with on-going behavior. Hundreds of photographs suggest the reason is a clinging remora, a small relatively inoffensive freeloader who scours tender dolphin skin for morsels to eat. Remoras don’t bite. They tickle. Calves are particularly likely to breach to remove remoras. Do remoras like calves more than adults? Or have adults learned to rub remoras off with a swift slide along the seafloor?
So when dolphins hurl themselves spectacularly skyward, they’re usually showing off. But for whom? It sure would help if they could wag a tail or something.
Dr. Weaver studies wild dolphins under federal permit GA1088-1815, National Oceanic and Atmospheric Administration. Send her an e-mail at acweaver@tampabay.rr.com or visit www.dazzlingdolphins.com.
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Article published on Thursday, March 6, 2008
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