Dolphins Wear Sponge Nose Guards to Forage

In the 1980's female dolphins were first seen using sponges as a foraging tool to protect their noses while digging at the ocean floor for prey. New research, however, conducted by a team from Georgetown University (go Hoyas, biotches!) has taken a much more comprehensive look at this use of tools by dolphins.

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So they can use tools. But this dolphin has clearly not yet mastered the use of female contraception.

Professor Janet Mann of Georgetown looked at a population of bottlenose dolphins in Shark Bay in Western Australia to observe the sponging behavior. Only female dolphins were witnessed using sponges as a means to protect their noses while disturbing the ocean floor, and only 11% seemed to display this behavior. When they located prey, the dolphins would drop the sponges and attack it, only to pick back up their tools when they were finished. Professor Mann concluded that females learned this behavior while still weaning (while male dolphins preferred to socialize during this time). She also found that the female dolphins who used sponges (spongers), "were more solitary, spent more time in deep water channel habitats, dived for longer durations, and devoted more time to foraging than non-spongers."

Previously, chimpanzees were the only vertebrates observed habitually using tools to hunt for prey, so this study has significant ramifications. In fact, Professor Mann told the Daily Mail that the spongers spend "more time hunting with tools than any nonhuman animal." Probably more than some human animals as well!

Her research can be found in December's issue of PLoS ONE.


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The New Caledonian Crow doesn't count?

Interesting. . . I never knew that. cool.:D

By Ilovemyfuzzies (not verified) on 05 Jan 2009 #permalink

Previously, chimpanzees were the only vertebrates observed habitually using tools to hunt for prey...

Well, some humans do, too, though I suppose it's possible that no one was observing them!

Reminds me of the time I was in Bruges and I asked a woman at the counter of a chocolate shop if she only spoke Flemish. Of course, I did this while we were conversing in English. Brilliant...

It occurs to me to wonder (perhaps pointlessly) what such dolphins would make of the spongy foam "number one" hands?

I read a while back (like when I was 8) about dolphins using scorpion fish to force eels out of crevices in rock.

And how is 'tool' being defined here? Is it using the definition of 'an object found and modified by the user?' I ask because it seems to exclude all the fifty billion examples of other species' tool usage I can think of, from just the Planet Earth series alone.

Animals using tools: I faintly recall reading about a group of orangutans that was observed using sticks to pry open prickly fruit with nutritious seeds inside. Other orang groups were unaware of this technique and avoided the fruit. (Or maybe were just smarter and realized it was not worth the trouble.)