Jeff,


One of the many species of birds that frequent our feeders or yard is the Red-breasted Nuthatch. Sometime after your e-mail, I was at the kitchen window and noticed less than the usual number of birds feeding, with the exception of species Black-capped Chickadees. The Chestnut-backed and all others had disappeared. Then I noticed something I had not previously seen: two Nuthatches, one behind and one within the squrrel- proof feeder were frozen- absolutely no movement for 15 minutes of this usually frenetic species. At first they looked like those molded birds often part of bird baths. I knew it could only mean one thing. The question was, which Accipiter? I did not see one. The next day one Nuthatch was frozen on the feeder and was looking at a young rat feeding on our deck (so was I). It was very focused on its movements- only its eyes moved. Then I noticed, in direct line beyond me, the Nuthatch and feeder was a Sharp-shinned Hawk- a beautiful adult male looking directly at the feeder- from 35 feet up and 170 feet away.


Thanks again for your observations.
Dan Reiff
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Joe,


I agree. I believe what you, others and I have observed is similar to those Lion and Zebra or other food sources we have all seen on National Geographic presentations. If the lions are no longer loafing and become active, sometimes after the prey is less aware and on an important nutrient source, including plants and water or necessary migratory route and rest, because of the prolonged inactive predator period, they may be surprised and caught unaware. They then are likely to use automatic, stereotypic species-specific, evasive behaviors. I also believe there are additional elements to complex interactive behavior. An extreme example occurs to me. Imagine a flock of migratory birds, deep in the Sahara desert. A Falcon arrives at an oasis far from any water or other nutrient source. The birds begin feeding, aware that the falcon is present. They need food, water and rest. They become hypervigalent to the predator's behavior, and flee or reel when charged. However, they need to remain present because there is no other nearby food source. So, they use individual and group flight and other skills to evade the Falcon and perhaps all but one survives that morning.


Thanks for the exchange of interesting e-mails.
Dan Reiff


----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
----- Forwarded Message -----
From: "Joseph BC Mackie" <joemackie.14 at comcast.net>
To: notcalm at comcast.net, "Jeff Kozma" <jcr_5105 at charter.net>
Cc: "Tweeters" <Tweeters at u.washington.edu>
Sent: Thursday, November 25, 2010 7:00:26 PM
Subject: Re: [Tweeters] unusual bird behavior



Hello Birders,

Over a few years of observation, my impression has been that prey of falcons and accipters are generally quite perceptive, i.e., if the predator has been successful in its hunt and is actively feeding or recently satiated, they seem to resume foraging with apparent immunity to the presence of said predator. They can tell if they're imminent potential targets or not by the behavior of the predator.

Cheers,
Joe Mackie
Bellingham


----- Original Message -----
From: notcalm at comcast.net
To: Jeff Kozma
Cc: Tweeters
Sent: Thursday, November 25, 2010 6:09 PM
Subject: Re: [Tweeters] unusual bird behavior


Hello Jeff,


Wow. How special to have a Kestrel in your yard!



I have observed Merlins and many Peregrines and a few Coopers and Sharp-shinned be near flocks of birds and the prey species and others appear more vigilant but continue feeding. After a falcon completes giving chase, the birds will land and begin feeding, sometimes close to where the Falcon is eating. I wonder how the birds were behaving before the Kestrel gave chase?


My observations and speculation have been that birds become hyper-vigilant and often more vocal when birds of prey are nearby in preparation for chase, but often remain feeding if they are on prime feeding grounds and quickly return following the chase to feeding at the same site if it provides a scarce or rich food source.


Like my Robin story yesterday, bare ground was very scarce, but a large group of them appeared and fed when I accidentally removed snow from small area of grass next to our driveway. They fed voraciously, in an unusually linear, dense cluster. Your rich and scare food source was probably necessary and the birds needed to stay. Perhaps if this was Summer and food was abundant they would have left.


Last year, I was filming a tightly clustered group of Pectoral Sandpipers in a Marsh, when a Merlin took one right in front of me, within seconds, a young Peregrine chased the Merlin, which dropped the SP. The peregrine then ate within close range of the original SP feeding site. The Pectorals took flight and landed within a short time (seconds) and distance and resumed feeding.


Dan Reiff
----- Original Message -----
From: "Jeff Kozma" <jcr_5105 at charter.net>
To: "Tweeters" <Tweeters at u.washington.edu>
Sent: Thursday, November 25, 2010 4:16:27 PM
Subject: [Tweeters] unusual bird behavior


Hi Tweeters,

When the weather gets really cold, and especially with snow on the ground, I
sometimes get a kestrel that visits my yard to attempt to pick of a bird to eat.
This afternoon, I looked out the window and saw the usual juncos and House
Finches feeding in the yard. I looked on the other side of my feeding area and
there was a male kestrel on the ground that was in the middle of eating a bird
it had caught. It was almost completely plucked and about half eaten so I
haven't identified the bird caught yet. What I was amazed at was that the birds
feeding in the yard were acting like it wasn't there. When it took off to my
neighbors roof to finish eating the bird, the birds in the yard never flushed
and kept on feeding like nothing was going on. Do birds not perceive the
kestrel as a threat? When a Sharp-shinned Hawk is in the yard eating a bird,
other birds completely disappear and do not return until the hawk has been gone
for some time. I know that kestrels prey on birds (although this is the first
time I have seen a kestrel eating an adult bird in my yard), especially young
birds and nestlings. I am totally perplexed as to why the birds in my yard
ignored the kestrel.

Any thoughts?

Jeff Kozma

Yakima (Terrace Heights)

j c r underscore 5105 at charter dot net


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