Ravens

'... the use of declarative gestures is not restricted to the primate lineage...'

-- The use of referential gestures in ravens (Corvus corax) in the wild

カラス

A Japanese study of urban crows found that the birds dropped hard-shelled nuts in the road at traffic intersections for cars to roll over and crack. When the traffic was heavy, the crows waited for the walk signal before grabbing their snacks from the street. How can you not admire that?

The crow's ability to adapt to man-made environments - in contrast to the struggles of more fragile species - has made it one of the planet's most successful bird species. But this achievement is the source of Haupt's ambivalence: it's everyone's loss, she reminds us, if we create an environment that accommodates only tough survivor species like the crow.

-- from a review by of Deborah Blum of Crow Planet by Lyanda Lynn Haupt.

Perhaps in the long run crows, rats, cockroaches and other 'tough' species will radiate into endless new forms most beautiful.

Rooks rock

Nowadays, we've had so many startling findings that the rooks just don't surprise me that much any more. You almost expect them to do the cleverest thing.

-- Nathan Emery quoted in BBC report (see also Ed Yong)

Foolin'

A bird watcher named Bill Reed observed and photographed a kittiwake in Svalbard seeming to fly upside down (see photo). What, he asks, is going on? I agree with those who say the bird is looking over its shoulder, not flying upside down. [1]

But observations of other birds flying upside down are said to well documented. In Pleasurable Kingdom: Animals and the Nature of Feeling Good, Jonathan Balcombe says there are many accounts of raven antics in [refereed] scientific journals and books. "A notable trick is flying upside down, sometimes for 100 meters or more."

The reason, he argues, is play -- behaviour that is both adaptive and pleasurable [2]:

in Iqualit, a village north of Hudson Bay, locals have seen ravens hanging upside down, swinging and somersaulting over powerlines, hanging from them with their bills, and sliding down roofs...On another occasion, two ravens played a form of 'rodeo' on two loosely strung, wind-whipped overhead power lines. They too turns trying to grasp the second wire in the bill and hand on as long as possible.

...Raven authority Bernd Heinrich has watched Houdi, one of the birds he raised from a chick, sliding and rolling on her back repeatedly down a two foot high snow mound.

(Photo of ravens borrowed from Maya's Granny.)

Footnotes

[1] (added 12 June): "Apparently this kind of twisting and turning is called 'whiffling'." See the comment at bottom of this post.

[2] If, as seems likely, this explanation is true, it is also the case that play is part of a rich array of behaviours. And there is an almost endless supply of stories about ravens. Among the ones included in Graeme Gibson's Bedside Book of Birds are two told by the unlikely pair of John Wesley and Farley Mowat. Wesley, writing in 1790, tells of an old raven that deeply in love with an old Newfoundland dog. It barks like the dog barks, is inconsolable when they are apart and collects food for the dog against its return. Mowat (in Westviking, 1965) tells the story of how Flóki Vilgerðarson's used ravens to find distant land on his navigation across the open ocean from Norway to Iceland (finding land, as Noah does, with a raven, the first bird mentioned in the Bible). "Some people deride this account as apocryphal," writes Mowat. "There is no reason to think it is anything of the sort. On the contrary, [raven-assisted navigation] was no more than what one might expected from a seafaring people who were very closely attuned to the world in which they lived". And then there is Italo Calvino's story Last Comes the Raven, recalling his days with the partisans...

Trickster (2)

A neat summary of recent findings about corvids here.



P.S. Joshua Klein on the intelligence of crows.

Trickster

Crows seem to be able to use causal reasoning to solve a problem, a feat previously undocumented in any other non-human animal, including chimps. They also rival primates in ability to deceive.

The storytellers would not be surprised:

[Raven] came to a place where many people were encamped fishing.... He entered a house and asked what they used for bait. They said, "Fat." Then he said, "Let me see you put enough on your hooks for bait," and he noticed carefully how they baited and handled their hooks. The next time they went out, he walked off behind a point and went underwater to get this bait. Now they got bites and pulled up quickly, but there was nothing on their hooks.

-- fragment of a Tlingit story as told by Lewis Hyde.