Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!hplabs!hpfcso!hppad!geleynse
From: geleynse@hppad.HP.COM (Martin Geleynse)
Newsgroups: rec.birds
Subject: Re: Peregrines & shorebirds
Message-ID: <2120001@hppad.HP.COM>
Date: 5 Sep 89 20:26:35 GMT
References: <1989Aug24.193532.6535@utzoo.uucp>
Organization: HP Panacom Automation Div Waterloo, Ont.
Lines: 68

With respect to the "request for comments" on falcon learning and the
response of falcons to the flocking behaviour of some prey species,
by mjm@oliven.olivetti.com (Michael Mammoser): I have observed this
predator avoidance technique a number of times in reaction to both
wild falcons, and those trained for falconry.

Several years ago I trained and flew a Merlin at startlings and
cowbirds which flock in early fall. Any time there were more than a
few individuals, the quarry would invariably form a tight "pack" an
fly in swirling circles. They would gradually make their way to some
dense cover, usually standing corn, which they would then dive into.
I noticed that the position of any one individual within the flock
was constantly changing. Individuals on the outside edge would be
"swallowed up" by a wave of birds from the top of the flock, for
example.

My Merlin would enter these flocks repeatedly, but she was never
successful.  With small groups of startlings, she could single out
one, and fly it down. Her success rate in these instances was
somewhere around 20%. As the season wore on she stopped entering the
large swirling masses of birds. Rather, she would "pace" them until
they reached cover. I am sure that, if a small group had broken away
from the flock, she would have persued with vigor. However, none ever
did.

I am leading up to two points: 

1)  Falcons are able to "learn" by trial and error experience, and
    modify there hunting techniques accordingly.  

2)  Experienced birds do not enter large flocks of prey because they 
    have learned that, as long as the flock is in formation, there is 
    essentially no chance of success. 

(In addition, it is very unlikely that a falcon could be hurt by striking
a bird a small as a plover. They will quite happily pile into something 
as large as a Mallard duck with no ill effects.)

The "learning" or refinement of hunting techniques is well
documented.  I refer those interested to the book "Fledgling
Behaviour of Peregrine Falcons" by Steve Sherrod. The fact that I can
release my Peregrine, which immediately climbs several hundred feet
into the air and circles directly above my dog pointing a covey of
partridge for ten minutes, until I arrive to flush, is further evidence of
a falcons ability to adapt its hunting behaviour, at least within limits.

Of course, during the entire training procedure, I do not beleive the
falcon used any abtract reasoning ability, rather, it formed an
increasingly stronger association between "correct behaviour" (go
high, watch dog) and desired result (dinner).

The observations of shallow stoops by a Peregrine on shore birds may
be explained in 2 ways:

1)  The falcon has, through trial and error, learned that this behaviour
    sometimes causes a few shorebirds to separate from the flock, and 
    thus become catchable. (pretty abstract - not likely).

2)  The falcon is singles out a bird on the edge of the flock, stoops,
    but looses sight of it in the flock before completeing the stoop. 
    Not having any quarry in sight, and having previously associated
    altitude with success, it pulls out of the stoop. (probably closer
    to the truth)
    

There's my two cents anyway,

Martin