Or just disposition, or whatever the non-anthropomorphic term for it
would be. If you ever have a chance to work on a study of one species
of birds, it may be surprising how much the behavior traits vary among
I've assisted on long-term studies of nesting kestrels and tree
swallows, and with both species, the range of nest defense behavior is
very noticeable-- very wide among kestrels, less so among the tree
swallows but still enough to be observable.
A less cheerful thought is that it might not be in as good health and is
preserving its energy.
On 1/17/2012 10:03 AM, MARIE HEMEON wrote:
> Could the aggressive behavior and, lack there of, be a function of sex or age?
> ----- Original Message -----
> From: Larry Clarfeld<mailto:[log in to unmask]>
> To: [log in to unmask]<mailto:[log in to unmask]>
> Sent: Tuesday, January 17, 2012 9:56 AM
> Subject: [VTBIRD] Varied Thrush - YES @ 8:30am 1/17
> Hi VTBirders,
> After arriving at Mountain Valley Farm at 8:15 this morning, I found a
> sign on the driveway directing birders towards a good area to view the
> bird without getting too close and scaring them away. After about 15
> minutes of watching, the Varied Thrush arrived, flew down to the stone
> wall, picked up a piece of corn, and flew back up to the trees. I was
> able to watch it for only about 30 seconds before it flew out of
> sight, and it didn't return during the 15 additional minutes that I
> remained there.
> Although I didn't see Gib or Sue while I was there, I certainly thank
> them for allowing guests! It was interesting how the behavior to this
> bird differed from the Varied Thrush in Bolton last winter, which
> would chase away other birds from the feeding station and hold its
> turf... it will be interesting to see how long it sticks around,
> Good birding,
> - Larry
> Larry Clarfeld
> Environmental Educator
> Youth Birding Coordinator
> North Branch Nature Center
> 713 Elm St.
> Montpelier, VT 05602
> (802) 229-6206
> [log in to unmask]<mailto:[log in to unmask]>
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