I want to thank all who have commented on this observation of bird behavior.
So many times these exchanges are taken "off list," denying the rest of us
the opportunity to learn. Thank you for making your comments public and for
sharing your knowledge.
So. Glens Falls, NY
----- Original Message -----
From: "Michael Blust" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, February 04, 2007 10:08 AM
Subject: Re: [VTBIRD] Pigeon -- Rock Dove Rescue
:I do not know what mechanism resulted in the behavior you observed. I
suspect physiological shock or perhaps being physically stunned. Many of us
have seen birds stun themselves by hitting windows and appear dead, only to
suddenly fly away. It is possible the hawk wound up stunning the cowbird
during the capture. Since this is not (as far as I know) a regular
behavior, all I can do is speculate. In any case, I too would have cheered
for the hawk and would have admired (though not necessarily cheered) the
"pluck" of the cowbird who avoided "the pluck".
: Michael Blust
: Dept. of Science
: Green Mountain College
: Poultney, VT
: From: Vermont Birds on behalf of Jane Stein
: Sent: Sun 2/4/2007 9:06 AM
: To: [log in to unmask]
: Subject: Re: [VTBIRD] Pigeon -- Rock Dove Rescue
: Michael, I couldn't possibly agree more with what you say here.
: Just to be clear, though, which of the possible explanations for the
: "playing dead" behavior is most likely is not a discussion I was trying
: to enter into.
: Also to be quite clear, I am vehemently opposed to the kind of
: sentimentalizing and gross anthropomorphizing one sometimes hears about
: bird (and animal) behavior. But on the other hand, I don't buy into the
: opposite idea, that critters are just little cookie-cutter automatons
: with zero awareness and zero ability to observe, draw conclusions, act
: on the conclusions and learn from experience. I think their ability to
: do that is certainly limited, but not altogether absent, and that we
: sometimes twist ourselves into real pretzels trying to find explanations
: for behavior that rely exclusively on physiology and/or genetic
: It is the job of scientists like you and Bill to do the work that
: laboriously teases out the mechanisms for those responses. It is our
: job, I think, to learn from you. But it's also our pleasure to observe
: and enjoy and marvel at what we see, whatever the mechanism is that
: produces it.
: Do you know, or does anybody know, what the mechanism is for the
: "playing dead" behavior I observed? I've seen a fair number of hawk
: prety captures, and I've never seen it any other time. I've seen
: captured prey become very still and I've seen them struggle violently,
: but I've never before or since seen one do what this cowbird did. It's
: the only time I've happened to see a hawk grab a cowbird, so I have no
: idea whether this is typical particularly of cowbirds or a rare
: miraculous (for the cowbird) coincidence of nerve-pinching released at
: precisely the right moment. Without further data, there's no way to
: make more than a wild guess.
: Whatever the mechanism, it was a wonderful thing to see. Being a hawk
: person, I confess I cheered when the little Sharpie blasted into the
: ball of blackbirds and came out the other side with lunch. But then I
: also had to cheer when the cowbird abruptly escaped what appeared to be
: his fate.
: Michael Blust wrote:
: > It does make a difference in terms of whether the response was an
: > instinctive response, an intellectual response, or a physiological
: > response. For instance, potential explanations might include that
: > the bird had temporarily gone into shock, that the hawk was pinching
: > on a nerve that rendered the prey temporarily helpless, that the
: > playing dead behavior was instinctive (and thus largely genetic and
: > therefore could be inherited), or that the playing dead behavior is
: > learned and thus not subject to direct inheritance. These all have
: > different implications for both the behavior of the predator and the
: > prey. They also have implications for heritability and therefore
: > evolution of the behavior.
: > In science, if you have one explanation that is supported by the
: > evidence, you may be right. If you have four explanations and the
: > evidence ONLY supports the one, you have a much stronger argument.
: > That is why Bill emphasizes to his students the importance of
: > alternative explanations. Thinking of alternatives is part of the
: > "art" of science, but as with all art, some people are into the
: > technical aspects, and others just enjoy what they experience. Both
: > have their place. And many of us enjoy both.
: > Michael Blust Dept. of Science Green Mountain College Poultney, VT
: > ________________________________
: > From: Vermont Birds on behalf of jane Sent: Sat 2/3/2007 9:54 PM To:
: > [log in to unmask] Subject: Re: [VTBIRD] Pigeon -- Rock Dove Rescue
: > Um, how is that different from what I said? I made no assumptions,
: > the bird clearly was "playing dead." That observation doesn't
: > preclude an instinctive response-- although I do think we sometimes
: > bend so far over backwards to try to explain away bird and animal
: > behavior as hard-wired "stumulus-respose" that we encroach pretty far
: > beyond Occam's razor.
: > The bird played dead. *Why* it played dead is not something I
: > speculated on, but others are certainly free to.
: > Jane Shoreham
: > William H. Barnard wrote:
: >> Jane's comments might be totally correct, but I would like to
: >> suggest to readers that observations in nature often have multiple
: >> explanations. Jane's explanation is one of many that might explain
: >> her observation. I do not believe that cowbirds or other birds have
: >> the cognative powers to "play dead" when attacked by a hawk. Much
: >> as we might like to think that our birds have that ability,
: >> research might suggest that they are more "creatures of the moment"
: >> and live their lives, for the most part, by responding in very
: >> stereotyped behaviors to stimuli. Evidence of a thought process or
: >> learning in birds is present in the literature but not the norm.
: >> I always try to teach my students to look for alternative
: >> explanations and not grab the one's that are often driven by
: >> anthropomorphism.
: >> Bill Barnard
: >> -----Original Message----- From: Vermont Birds
: >> [mailto:[log in to unmask]] On Behalf Of jane Sent: Saturday,
: >> February 03, 2007 6:59 PM To: [log in to unmask] Subject: Re:
: >> [VTBIRD] Pigeon -- Rock Dove Rescue
: >> Great story! I read/saw somewhere that although Rock Doves may
: >> look stupid, they've exhibited the greatest cognitive ability of
: >> any bird, including crows, researchers have tested. It one of
: >> those studies involving pecking the right picture to get a food
: >> pellet, and the Rock Doves quickly learned to distinguish between
: >> photographs and artwork, and then actually between artists. If I
: >> remember right, it was something like Picasso and Monet they
: >> ultimately tested them on. Hard to believe.
: >> Some winters ago, I saw a little male Sharpie plunge into one of
: >> those big balls of blackbirds in a farm field in Addison and come
: >> out the other side with what looked like a cowbird in his claws.
: >> He took it over to a nearby barn roof and sat down with it and
: >> pulled a couple of feathers. The cowbird was completely splayed
: >> out, limp, head fallen back, wings open and drooping, looked quite
: >> dead.
: >> Then the Sharpie decided he didn't want to have his lunch with me
: >> watching, I guess, and lifted off to go somewhere else. He must
: >> have loosened his grip just for a second because the cowbird
: >> instantly came to life, jerked free and dove down out of my sight.
: >> Sharpie learned a lesson, I think. I didn't know birds would play
: >> dead to that extent. The cowbird wasn't just still, it let itself
: >> go completely limp in the hawk's talons and just waited for a lapse
: >> of concentration.
: >> Jane Shoreham
: >> William Gilbert wrote:
: >>> While watching a large flock of some 35 rock doves ground feeding
: >>> a
: >> hawk
: >>> flashed into view and took one of the suddenly fleeing Rock Doves
: >>> to
: >> the
: >>> ground. The others all disappeared to a roof top they favor.
: >>> As the Hawk prepared to dine while standing on the pigeon and
: >>> plucking feathers, the captive, coming back to life, broke loose
: >>> and tried to
: >> escape.
: >>> It made it into the air about 25 to 30 feet with the hawk in hot
: >> pursuit,
: >>> when the flock appeared again and flew into the path of the two
: >>> birds.
: >> In
: >>> the confusion the hawk lost its prey.
: >>> Sure looked like a rescue.