Via Treehugger and the Science Bulletin of the American Museum of Natural History comes an unusual report of bottlenose dolphins (Tursiops truncatus) sliding down the noses of humpback whales (Megaptera novaeangliae), an observation originally reported two years ago in a paper by Deakos et al. The behavior was seen twice (nice to get a paper out of about ten seconds of observation!). Here’s a video version of the report:
Here’s one observation described in the paper:
At 1427 h, two adult-sized dolphins (approximately 3 m in length) reversed direction and approached the humpback whales. The dolphins positioned themselves directly in front of one humpback still at the surface and appeared to surf the pressure wave created by the whale’s head as it swam. The two dolphins could be differentiated since one of them had a distinctive cookie cutter shark (Isistius brasiliensis) bite on the right side of the body and a notched dorsal fin. During the next two breaths by the same whale, each dolphin independently was seen lying across the whale’s rostrum as it surfaced, oriented perpendicular to the whale’s body. At 1430 h, the whale stopped and slowly raised its rostrum upward while lifting the well-marked dolphin out of the water (Figure 1a). Once completely clear of the water, the dolphin remained arched, on its side, balanced over the end of the whale’s rostrum (Figure 1b). The dolphin appeared to cooperate, with no discernible effort to free itself or escape. When the whale was nearly vertical, with its eye nearly breaking the water surface, the dolphin slid down the dorsal side of the rostrum (Figure 1c) while swinging its flukes upward (Figure 1d). This entire lift sequence lasted about 3 s, ending when the dolphin entered the water tail first.
What in the world is going on here? The authors suggest a number of hypotheses:
- The whale is pwning the dolphin. Dolphins are known to surf the “pressure wave” in front of swimming humpback whales, and this could piss off the whale. The lifting of the dolphin could result from a head lunge by the whale, and head lunges are known to be part of the whale species’ aggressive behavior. The authors discount this because the head lunge was so slow, and the dolphin didn’t appear to flee it.
- The whale is helping a distressed dolphin. This is called succorant behavior, and has been seen in other marine mammals, though it’s very rare in baleen whales. The authors discount this because the dolphin didn’t appear injured or distressed. Also, if the action was merely a maternal response by a misguided female humpback whale (sex was not determined), that wouldn’t explain the dolphin’s “cooperative” behavior.
- They’re playing! Both bottlenose dolphins and humpback whales have been reported to engage in play-like behavior. The authors suspect that this is the most likely explanation—that “social play” was initiated by the dolphin, perhaps stimulating a maternal effect on the part of the whale.
__________
Deakos, M. H., B. K. Branstetter, L. Mazzuca, D. Fertl, and J. R. Mobley, Jr.. 2010. Two unusual interactions between a bottlenose dolphin (Tursiops truncatus) and a humpback whale (Megaptera novaeangliae) in Hawaiian waters. Aquatic Mammals 36:121-128.
Cetaceans just wanna have fun!
/@
That one’s a real dive – totally tanked.
Are they doing it on porpoise?
Yes, and they’re having a whale of a time.
Would you two stop spouting off!
You think cetaceans do puns? Are they a sign of true intelligence, or a sign that we have a long way to go in that department?
Cetacean intelligence is just a fluke of evolution…
/@
The problem is that any cetacean can blow holes in our theories, just for sheer pwnage.
These puns are krilling me.
Don’t flipper out now.
please don’t blubber.
The thing about whale puns is that it’s easy to cachalot of them if you try.
“I’m from what, on your calendar, would be the late 23rd century. I’ve been sent back in time to bring two humpback whales with me in an attempt to repopulate the species.”
It’s not just the whales – it’s the water!
But do they have free willy?
Or just a noob-y dick?
I’m sure there’s been a study on this; I’ll see if I can’t find the cetacean.
Another possibility is that the whale is the dolphin’s pet. Dolphins are supposed to be pretty intelligent. Maybe it’s just as well they don’t live on land. I’m already owned by two cats.
My favorite quote from Douglas Adams’ The Hitch-Hiker’s Guide to the Galaxy:
“For instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so much – the wheel, New York, wars and so on – whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than man – for precisely the same reasons.”
I get a lot of mileage out of this too. It’s a nice, gentle way to remind people that maybe we’re not sure what we mean by “intelligence” just yet. And people almost always get a chuckle out of it.
Water we waiting for? Let’s fluken’ join in…
Wanted to read more about it, but hit the Aquatic Mammals paywall. Gonna have to go mug a university student for his ID again–though I think the police are starting to catch on . . .
Make sure it is a grad student, otherwise the authorities might take notice.
A theology grad student would willingly give it up if I told him that I was going to expose Aquatic Mammals as a hotbed of Evilutionist lies.
Is it possible that this is a good way for the dolphin to get a good back-scratch? Don’t know what’s in it for the whale, though.
Rostrum scratch. Obviously.
What a cool story! 😀
I think that you are right. What we call play in humans is essentially training for real life. The fact that we continue to play as adults could be preservation of that behaviour (infantilism?) in later life, or because adults have to be able to react at a play level with children, only sometimes we substitute other adults for children. Therefore I see no problem in call this play.
Another hypotheses could be highly evolved Photoshop implemented in an elaborate hoax. If real,the behavior could have developed gradually from the dolphin accidentally, partially stranding on and sliding off of the whale to “wow, let’s try that again”.
So we’re not the only ones who can see farther by (not) standing on the (not)shoulders of giants.