Chickens do the same thing so I suspect that the behavior is common in flocking
birds. Chickens will peck at and eventually kill an infirm or injured chicken
or sometimes just for no apparent reason. We kept a dozen or so hens when I was
growing up so I'm very familiar with the behavior. Sometimes you can segregate
a hen until the wounds heal and they will leave it alone. If the bird appeared
to be sick or pecked at too much before they caught it my parents would kill the
chicken quickly to stop it's suffering. Hens actually make good pets. Most of
them come to like being held and stroked and will make a soft clucking noise
that is pretty much the equivalent of a cat's purr but then when they've had
enough the can turn on you and give you a good peck without warning then flap
angerly away only to come back later for more neck and back rubs. I'm sure it
all makes sense to birds though. There is something about the picked on bird
that disturbs the flocks social order or their safety in that they may
understand that it is sick and therefor a threat to the rest of them. Of course
my parents also said that birds just have a mean streak that we don't understand
which may be as good an answer as any.


Ray Holden
Olympia




________________________________
From: Barbara Deihl <barbdeihl at comcast.net>
To: Tweeters at u.washington.edu
Sent: Mon, June 13, 2011 4:11:42 PM
Subject: [Tweeters] Re: crow behavior question -

Hi Tweets and Judy and Linda,

I wrote to Tony Angell, one of the authors of "In the Company of Crows and
Ravens", and asked him his thoughts and whether or not he and John Marzluff
dealt with this in either their book or in the PBS special that aired last fall.
Here are his comments.
As Tony is not a "Tweet", I will forward any responses to him and then post for
him again, if his response is requested. Feel free to post your responses
either on Tweeters or offlist to me or both.
Interesting...

As I write, the crows in my yard are both harrassing their own and other
species! No death knell, do I hear...

--------------------this, from Tony:


Hi Barb:
>>
>>
>>Yes, we discuss this behavior to some degree in our book, In the Company of
>>Crows and Ravens, but like many mysteries regarding crows, this one's solution
>>is incomplete. One thing seems certain, there seems to be some murderous
>>punishment dispensed by crows towards other crows. The problem is that we
>>really don't understand the source of the wrath (territorial dispute, disease,
>>revenge of some sort)? That the other bird appeared injured may well have been
>>the result of the original assault and the team of crows were seeking to finish
>>off the offender -- crow execution. Then too, we don't know if the injured crow
>>(with a condition unrelated to an injury inflicted by other crows) was in such a
>>condition that dispatching it was essentially putting it out of it's misery in a
>>response not unlike our shooting a horse to relieve its pain inasmuch as it is
>>beyond any chance of survival.++
>>
>>
>>I realize that the above is speculation but as we have learned, from
>>speculation/hypothesis come fact and there are still a lot of facts to learn on
>>these species.
>>
>>
>>Best,
>>
>>
>>Tony
>>
>>
>>++ Oddly enough, shooting the horse is more an example of altruism, but in the
>>crow's case it could be an extreme form of kin selection as it would ultimately
>>relieve the suffering kin folk from pain.
>>
>>

-----------------------


Barb Deihl

North Matthews Beach - NE Seattle

barbdeihl at comcast.net