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Dolphin Watch
The brass ring
By ANN WEAVER
Article published on Thursday, June 28, 2007
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![[Image]](/content_images/062807_out-01.jpg) |
| Photo by ANN WEAVER |
| Bottlenose dolphin bull N (right) is boldest with burly bull Midface (left), named for notches half way down his dorsal fin that look like a face in silhouette. |
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The first of 77 million baby boomers have turned 60 years old. Addressing the potential of their memory-lapse marketplace, the computer industry offers various mental gyms (software). The enticement: To keep your memory, keep learning.
For physical human maladies, we turn to the animal kingdom. We test all drugs on animals. We study animals like sharks that don't get cancer. We'll take any animal adaptation that prolongs human life.
Can animals help with memory? What insight do they provide into the connection between living by your wits and mental health? If there's a biological basis for that connection, the study of animal behavior has important contributions.
Among John's Pass 180 dolphins is a bull named N. We were half way through the alphabet, naming dolphins with gender-free letters, when we first saw him.
N lives around here. Though mortgaged humans may be surprised that animals who swim 24-hours a day actually live somewhere, scientists label dolphins as resident or transient by how often they're seen. We've seen N on 56% of the 53 surveys we done so far this year.
Never one to shirk social opportunities, N's social life has been particularly stimulating of late with, it'd seem, commensurate demands on his mental abilities. Though we never know what a wild dolphin thinks, my guess is that N's brain has been working out lately.
N is very social. He's never alone. And he swims with a variety of dolphins, no small memory task. He is, not surprisingly, keenest about adult females without calves. He dogs DD1 at every chance; she's not easily persuaded. He travels with P and Q. He hounded Courtney last month. He got a new opportunity last weekend.
Social attitudes vary with your companions. Most people are bolder in the company of their staunchest supporters. This is true for animals too. At the San Diego Zoo, the gentle female gorilla Alvila had low status unless her beloved keeper Gale Foland was near. Gorillas who threatened Alvila retreated when Gale came into view, whereupon Alvila gave the deep moans of gorilla satisfaction. Before you laugh, humans make the same spontaneous sounds when eating something delicious.
N is boldest with burly bull Midface. Midface travels a lot. But when he's in town, he and N roam together. N is most likely to fight when with Midface. Otherwise, he swims with DD2.
Late June, a cadre of dolphins scattered across the shallows inside John's Pass. Young bull Riptab swung by the boat but continued on. It was soon obvious why.
Six dolphins comprised the cadre. Tanks, Law, her calf Quatro and LA Stick hunted. LA Stick's newborn calf, which should've been glued to her side, was nowhere to be seen. Bulls Edge and KK were glued to her instead.
With the loss of the calf, LA Stick became the newest available female. Edge and KK had the advantage of protective proximity to her.
But they had to maintain it.
N and Midface roamed the periphery. They too swung by the boat and continued on. Outgunned, neither the lone bull nor smaller pair seemed willing to tangle with Edge and KK.
The cadre headed north and milled off Little Bird Key.
Further north, bulls BB and DD2 were busy hunting. Their intense vocalizations blasted prey from the ocean floor. Surface trails of glassy circles and mudplumes signaled the sites of their efforts.
Three hours later the cadre, still milling around Little Bird Key, now included Face and Baby Face, Sponge and pal Pepto (for its very pink belly), and LA Stick's older calf Cactus. We hadn't seen Cactus and LA Stick together since January. I collected data and headed off to finish the survey. The dolphins went in the same direction so I paced them.
In a boat, you monitor 360 degrees. Scanning at one point, I saw two dolphins swimming in my wake. They trailed the cadre at a distance but never joined it. I call such dolphins 'trailers.'
They moved synchronously a half body length apart: competitive bulls. I squinted. The trailers were N and Midface.
N and Midface knew the cadre well. Without Edge and KK, they could've joined directly. But they didn't. They played 'stealth dolphin,' maybe even hiding in my wake.
Eventually, two more bulls approached from behind, BB and DD2. That made sense. They could've easily heard the babbling cadre from their hunting site.
Unlike N and Midface, they joined the cadre directly. Both are relatively peaceful bulls. Maybe that's why.
For a beefy bull, BB avoids conflict. However, brutal scars indicate he was attacked seriously in the past. He knows how much fights can hurt. DD2 rarely fights. When he does, he helps N.
Six bottlenose bulls and a female to fight over is a fuse waiting for fire. Enter the final pair.
These allies turned the tide for N and Midface, who seized the moment and charged into the cadre. I braced when Face surfaced with Baby Face several yards away. She's no fool.
Two dolphins torpedoed spectacularly across turquoise shallows as fast as I've ever seen. More bodies followed, splitting the water surface into rooster-tails in synchronous pursuit. They covered hundreds of yards in a blink.
Face surfaced, BB with her. He hadn't helped chase Edge and KK away. The remaining cadre moved on like an elephant herd ignoring the tantrum of a single elephant.
Edge and KK didn't give up. So much for LA Stick's moment of peace. But the chase worked.
One by one, all the bulls rejoined the cadre. N and Midface returned first, claiming privileged proximity to LA Stick. The hubbub attracted new dolphins like people to a brawl in a mall: females Stick and Scrapefin were soon embroiled in taking some heat off LA Stick. Ousted bulls Edge and KK swam at the edge of the cadre, slamming fish much harder and higher than necessary.
Remember the details; their story doesn't end here. However, this story must.
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.
Other stories about these dolphins
Out of the Blue, Sea Spats, Ya Wanna Fight? Take it to the Flats!, Food Court, Persistence Pays, Attack of the Oyster, The Cost of Competence, Move Over, Baby Face!
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Article published on Thursday, June 28, 2007
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