Bill,

Sorry, but the word "strategy" is much used in biology meaning an
evolutionary strategy, not meant to imply that an individual bird
uses a strategy in the same way that humans do.

"The predators' strategy" is merely the behavior that has worked best
over time and has therefore been more or less fixed in the
population, as those individuals that didn't practice it were less
successful. This is called an evolutionarily stable strategy in
evolutionary biology, and much thought has been given to how
alternative strategies arise by mutation/natural selection and become
fixed in a population.* Given that context, "a really smart Sharp-
shinned Hawk" is one with a mutation that has resulted in its waiting
until a bunch of birds have assembled before making its predation
attempt. That kind of Sharp-shinned Hawk would increase in the
population, if indeed it had more successful hunting. But the fact
that we don't seem to find that means that either there was no such
mutation or that in fact it wasn't successful.

I would argue with you about the predictive power of animals, though.
When a lion comes to a waterhole or a chickadee to a feeder, it's
predicting that there will be something to eat there because it has
seen its food items there many times before. I believe that's the
essence of prediction, even though it's from observational learning,
not formulating a hypothesis and testing it.

There's a certain amount of irony in your telling me "let's not
anthropomorphize," as most of my adult life spent as an educator has
included the same suggestion to others. I'll have to watch my
language from now on.

Dennis

* Here's an example. When I was a boy birdwatcher visiting southern
California, I saw Heermann's Gulls with white wing patches (white
upper primary coverts) pretty often. I estimated that they occurred
in about 1 in 100 birds, and I would sometimes see several in a day.
I hypothesized that these patches made them more jaeger-like, perhaps
increasing their prowess in stealing food from other fish-eating
birds. I wondered to myself if that particular mutant would continue
to increase in the population (the end point of which would be white
wing patches in all Heermann's). From what I see now, I would say
that on the contrary it has declined, as I almost never see them now,
even in flocks of hundreds of Heermann's. Amazingly, the Birds of
North America account of this species scarcely mentions this
interesting plumage, only the original report of it in 1918.

On Oct 6, 2006, at 6:00 PM, William Kaufman wrote:

>
> I see the same activity but let's not anthropomorphize ;
> "that a common avian strategy . . . , indicating no predators
> around . . .., a really smart sharp-shinned hawk or cat. . . . "
> Yes they probably can think - observation or training - to a
> degree - but not to predict.
>
> Bill Kaufman
> Woodinville, WA
>
>
> on 10/6/06 6:47 PM, Dennis Paulson at dennispaulson at comcast.net wrote:
>
> Hello, tweets.
>
> I just observed a remarkable phenomenon in my yard that I've seen
> many times, but I thought I'd pass it on.
>
> The yard was pretty quiet, then a few birds showed up, then I
> noticed a number of robins coming to the fountain/bird bath. I
> started watching, and within minutes, one species after another
> came to the water, chickadees, juncos, House Finches, House
> Sparrows, Song Sparrow. Meanwhile, there were birds at all the
> feeders, birds flying back and forth across the yard, birds picking
> insects off the windowsill, and just a flurry of birds everywhere.
> I watched in amazement as a goldfinch came to the fountain - first
> one I've seen in the yard in 7 years. Then my only Townsend's
> Warbler so far of this fall right after it. Then activity died down
> somewhat, but there were still a few birds in sight, and 20 minutes
> later there was an Orange-crowned Warbler in the fountain, first
> one I've seen here this year. You have to understand that my yard
> isn't exactly jumping with warblers, and in fact I don't see as
> many as I used to. I don't think it's because I'm looking out the
> window any less.
>
> Anyway, quite some time ago it seemed obvious to me that a common
> avian strategy is to come out in the open only when other birds are
> already out there behaving normally, indicating no predators
> around, and that's what I see over and over again in my yard. No
> birds at all, then a burst of activity with numerous species, then
> back to dead quiet. A really smart Sharp-shinned Hawk or cat would
> wait until the middle of one of those flurries, then strike, but it
> may be that the predators' strategy is to attempt to catch the
> first bird they see, as (a) it might be the only bird around or (b)
> another predator might be watching and get there first.
>
>
> -----
>
> Dennis Paulson
>
> 1724 NE 98 St.
>
> Seattle, WA 98115
>
> 206-528-1382
>
> dennispaulson at comcast.net
>
>
> _______________________________________________
> Tweeters mailing list
> Tweeters at u.washington.edu
> http://mailman1.u.washington.edu/mailman/listinfo/tweeters
>
>

-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman1.u.washington.edu/pipermail/tweeters/attachments/20061007/102c9c5d/attachment.htm