Date: 6/27/18 11:36 am From: DAVID A LEATHERMAN <daleatherman...> Subject: Re: [cobirds] Singing Cordilleran Flycatcher, Lafayette, Boulder
I would add Pine Siskin, Western Wood-Pewee, Ruby-crowned Kinglet, Broad-tailed Hummingbird, Chipping Sparrow, and probably others besides what Chuck and Nathan already mentioned, to the list of mountain species increasingly occurring at low elevation during summer. My take is that urban tree plantings, particularly in big yards, parks and cemeteries, are maturing and, thus, increasingly provide what these birds need. I imagine, depending on the year, fires and a shortage of conifer cones and other foods (i.e., habitat hardships in the mountains), also play roles in how many of the mountain species seek their fortunes elsewhere (think Red Crossbill).
From: <cobirds...> <cobirds...> on behalf of Nathan Pieplow <npieplow...>
Sent: Wednesday, June 27, 2018 10:12 AM
Subject: Re: [cobirds] Singing Cordilleran Flycatcher, Lafayette, Boulder
On the topic of montane species nesting in lowland areas: a pair of Gray-headed Juncos apparently nested in the middle of Boulder this spring, on the creek behind the Basemar shopping center (same spot where the Varied Thrush and Black-throated Blue Warbler were hanging out last fall). I saw an adult singing persistently there on 5/10 and 5/30, and found the adult tending a brown streaky juvenile on 6/15.
Looks like Andy Belt reported a Gray-headed Junco at Rocky Mountain Arsenal on 6/19, too.
On Wed, Jun 27, 2018 at 8:52 AM Charles Hundertmark <chundertmark8...><mailto:<chundertmark8...>> wrote:
This morning from my bedroom window I heard a Cordilleran Flycatcher singing in the wooded stretch along an irrigation ditch. I first heard a Cordilleran singing in the neighborhood on June 11. I was out of town from June 12-20. Since returning, I’ve been hearing the Cordilleran calling on multiple days in the same vicinity.
On June 12, Richard Pautsch reported a persistently singing Cordilleran in Denver.
Are Cordilleran Flycatchers joining the growing list of montane species moving into lowland habitats? In Lynn Wickersham’s account for this species in The Second Colorado Breeding Bird Atlas, she notes that the species’ population has been increasing and suggests that “…increasing availability of manmade nest substrates…” may be contributing to the increase. Are suburban homes providing a nest substrate the way cabins have in the mountains? Do riparian strips along streams and irrigation ditches provide corridors for movement?
Will Cordilleran join Bushtits and Red-breasted Nuthatches in the list of montane species moving into lowland areas?
"What does not change / is the will to change” The Kingfishers, Charles Olson