[CT Birds] Corvids at Play
LS.BROKER at COX.NET
Mon Jan 23 16:22:29 EST 2012
From Steve Broker (Cheshire):
Play behavior by ravens and other corvids has been documented widely. Derek Ratcliffe (1997) summarizes reported examples of ravens at play in his excellent book, The Raven: A Natural History in Britain and Ireland (London: T&AD Poyser, 326pp.) Ratcliffe writes, "Play, especially in the form of 'snow-romping' is reported by various observers." He cites examples of raven play observed by Bernd Heinrich (see 1989. Ravens in Winter and 1999. Mind of the Raven), who "also described Ravens in Maine snow-bathing, kicking snow, sliding on their breasts and rolling on their backs in it, apparently for fun, 'like happy dogs'." Ratcliffe continues, "Gwinner had captive birds that repeatedly slid down an inclined, shiny piece of board . . ." [Sounds remarkably like the recent YouTube post on this listserv.]
Other play behaviors described by Ratcliffe include the following: (1) "Tony Cross has seen birds bouncing up and down on the very end of a long, dead branch, by holding on with their beaks and with their swings closed tight against their bodies. He has on numerous occasions watched Ravens taking sticks, turf and sheep droppings aloft, dropping them and trying to catch them again before they hit the ground." (2) "Gwinner also recorded his captive Ravens indulging over 300 times in 'upside down hanging', a curious behavioural trick known also in other corvids, but for which no functional explanation is yet forthcoming. It is performed especially by young birds up to 2 years old." (3) "One of the most oft-remarked quirks of tame Ravens is their playing of tricks on other animals, especially cats and dogs. A favourite ruse is to sidle up to a sleeping animal and tweak its tail, quickly jumping back or flapping up to a higher perch before the enraged animal can retaliate." Ratcliffe notes that such "risky actions may well be related to the stealing of food from other predators . . . yet, some of these attacks seem more in the nature of devilry . . ."
Two other book publications that provide important insights into animal (bird) play are: (1) Griffin, Donald R. 2001. Animal Minds: Beyond Cognition to Consciousness. Chicago: The University of Chicago Press, 355pp.; (2) Bekoff, Marc. 2007. The Emotional Lives of Animals. Novato, California: New World Library, 215pp.
In Connecticut, I have been observing Common Ravens at West Rock Ridge State Park for the past ten years, and I have seen the West Rock ravens at play numerous times. The birds have exhibited various forms of play, including rolling over and sliding down a steep snowbank on their backs and also carrying stones in their bills, dropping them, and trying to swoop down and catch the stones in the air. Writer Kathleen Kudlinski's latest contribution to her excellent "The Naturalist" column in the New Haven Register (on-line today and in yesterday's paper, I believe) focuses on ravens and their intelligence and lists some of these observed behaviors.
Ravens are among the earliest nesting birds in their breeding ranges, and the rebuilding of last year's nest at West Rock will begin by the last two weeks in February. Let the games - for real and for play - begin!
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