Both the eagles in your photos are Bald Eagles. Bald Eagles are very
territorial and deaths in territorial eagle encounters are rare but known to
happen. My knowledge is first hand from having been involved in Bald Eagle
biology for almost 30 years in the Midwest. I or my colleagues twice found
dead adult eagles, with fresh and bloody puncture wounds on the feet and body,
near active nests. Additionally, Great Horned Owls and other large Bubo owls
are not afraid to enter eagle nests after dark and have been filmed, with
infrared digital video, trying to snatch young eagles in the presence the
adults at night.
Whether or not "subadult" eagles engage in any nest related activities is a
matter of definition of "subadult". There's video of a color-banded (banded by
me) 3-year old Bald Eagle nesting in southern Kansas. Her plumage was one of a
near-adult; she had a dark horizontal bar across her eye and head. So, her
plumage might have been called subadult, but she was successfully reproducing.
An account of this has been published in the Journal of Raptor
Research--Mulhern, Daniel W., Michael A. Watkins, M. Alan Jenkins and Steve K.
Sherrod. 1994. Successful nesting by a pair of Bald Eagles at ages three and
four. Journal of Raptor Research 28(2):113-114.
Lastly, I feel that the twirling of eagles is territorial, not courting
behavior as many have said. If we could know the gender of the twirling eagle
I think they would turn out to be the same sex and know for sure. There was a
video taken near Portland, not too long ago and broadcast, where both eagles
looked, to me, like males. Also, Australian White-bellied Sea Eagles,
Haliaeetus leucogaster, have been filmed showing one member of a pair flying to
intercept and twirl with an intruding eagle.
Alan Jenkins
Creswell, OR
________________________________
From: obol-bounce@xxxxxxxxxxxxx <obol-bounce@xxxxxxxxxxxxx> on behalf of Judy
Todd <judy@xxxxxxxxxxxxxxxxxxx>
Sent: Monday, February 11, 2019 5:21 PM
To: obol
Subject: [obol] Eagle ID?
A friend took these after watching the drama and chase. Does it appear that the
'intruder' was a golden? What other eagle would chase or wound resident bald
eagle adults or juveniles near their nest? Any ideas? Near ponds at Molalla,
OR. Judy Todd, 503-260-4995
