[midvalleybirds] RE: [COBOL] Amazing number of eagles in Powell Butte

tom at barbless.com tom at barbless.com
Fri Mar 1 10:29:31 PST 2019

+Mid Valley Birding wrt Tangent,

Is there a scientific definition of "eagle roost"? Quick googling yields varied discussion that I would dangerously summarize as: 'communal night roosts for sleeping' and 'scattered day perches for hunting'. Some roosts are just used for days+ instead of year after year, and should be called 'transitory roosts'. Roosts sizes are 'from one up to several hundred adjacent trees' or 'trees within 100 meters of each other'.

Having commuted on the southern edge of the so-called Tangent Night Roost 400+ times (Bell Plain Dr), I often see up to 23 individuals in small groups over several square miles (Paul's "forage during the day over quite a wide area"). When livestock are down, said individuals and small-groups will concentrate into a single 40 acre field.

For the mid-valley birders, is there a clump of trees that represent THE Tangent Roost, or is it just the region? One seemingly authoritative eagle roost mapping site shows many roosts in Oregon, but nothing for the Tangent Roost.


Maybe I/we need to get the Tangent Roost listed?


-----Original Message-----
From: COBOL at groups.io <COBOL at groups.io> On Behalf Of Paul Sullivan
Sent: Thursday, February 28, 2019 8:34 PM
To: COBOL at groups.io
Subject: Re: [COBOL] Amazing number of eagles in Powell Butte

Chuck et al,

Are you aware of the Bald Eagle nightly roost near Tangent that get 50 or more birds at its peak?   Also consider the night roost at the Bear Valley NWR west of Worden (south of Klamath Falls).

 I think these roosts are comprised of birds that fan out to forage during the day over quite a wide area, then come together at dusk to spend the night together.

Why?  Certainly the Bear Valley refuge roost provides shelter from winter storms.

Paul Sullivan

-----Original Message-----
From: COBOL at groups.io [mailto:COBOL at groups.io] On Behalf Of Chuck Gates
Sent: Thursday, February 28, 2019 7:24 PM
To: COBOL <COBOL at groups.io>
Subject: [COBOL] Amazing number of eagles in Powell Butte

Cindy Zalunardo called me and said she had 14 Bald Eagles in one roost tree around 6:00PM tonight on Parrish Lane east of Powell Butte.  There was just enough light that I thought I would go check it out.  Of course she did not have 14 Bald Eagles in one tree.  That would be ridiculous. She had 20.  Though the light had faded by 6:30, it was still easy to make out all 20 in the last light of the day.  Absolutely amazing.  I looked it up, 57 is the highest number of Bald Eagles seen in one day. That was along the Crooked River in 1988 (Eagle Eye) but that was over a 
20+ mile route.  Of the 22 times that more than 20 Bald Eagles have been
reported from one site, most of them come from Wickiup which covers a huge area.  I think this is the largest number of eagles reported in one tree from Central Oregon since record keeping started.  Another great find by Cindy Z.

The mystery is why so many.  Are they using Houston Lake?  I was there just there two days ago and there was only one Baldy there. Where did these guys come from?  A typical raptor route tally for all of Powell Butte usually has less than 5 Bald Eagles.  Hmm.

It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so.
Mark Twain

Chuck Gates
Prineville Bird Club
Powell Butte,
Central Oregon Oregon Birding Site Guide http://www.ecaudubon.org/birding-locations
Oregon County Checklists

Groups.io Links: You receive all messages sent to this group.

View/Reply Online (#293): https://groups.io/g/COBOL/message/293
Mute This Topic: https://groups.io/mt/30171211/1700290
Group Owner: COBOL+owner at groups.io
Unsubscribe: https://groups.io/g/COBOL/leave/3732997/1694931633/xyzzy  [tom at barbless.com]

More information about the birding mailing list