Denver West Office Complex & Aurora Reservoir

October 21, 2019

Richard Stevens:

Temperatures only reached 52 degrees on this cold Monday.  Winds were 7-8 mph with gusts to 15 mph.

After waiting for rush hour to end, I drove to the Denver West Office Complex (Jefferson County).  The action was along the southern side of building # 6.

First, the Magnolia Warbler flew into the pines at the southeast corner.  It was followed by two Townsend's Warblers one of which flew down to the creek for a bath (photos on Colorado Birding Society's website eventually).

Three or four Yellow-rumped Warblers fluttered about the deciduous trees next to the building.  A pair of Ruby-crowned Kinglets and two Red-breasted Nuthatches also visited the pine trees.

Finally, the Nashville Warbler made an appearance.  The warbler stayed mostly deep in the pines; however, it did emerge several times allowing for identification looks.

My next stop was Aurora Reservoir (Arapahoe).  Hundreds of gulls stood on the swim beach.  Highlights were three Iceland Gulls and two adult Lesser Black-backed Gulls.

Around 4:00 pm, most of the gulls on the swim beach flew up.  I looked around for a reason (no people around) and observed a Jaeger chasing a couple of gulls.

I looked for the white flashes on the under wing and upper wing.  It had short pointed central tail feathers, dark brown cap and dark bill.  It looked similar to the Parasitic Jaeger photos from Warren Lake (Larimer).  Perhaps it was the same bird?

After 15-20 minutes, it followed gulls and disappeared below the dam.  I circled around but did not see the bird again.

On the way home, I stopped by Cherry Creek Reservoir (Arapahoe) to see if the Semipalmated Plover was still there (to update a friend).  It was not there.  Neither were the two Western Sandpipers and Lesser Yellowlegs (with broken foot).  They appeared to stay together since October 18.