Bird ID question - Purple Martin?

[Jeff Parks]

Hello all -

I was birding in the Shanahan Ridge area outside of Boulder yesterday, and saw what I thought were swallows flitting around.  While I was watching another bird, a couple of these birds landed on a dead tree nearby, and I took a quick look at them.  They didn't look like tree swallows, although they were dark blue on the back.  I pulled out my camera and tried to get a few pictures of them while they were still there, and managed to get some, although they are not very good.  After looking at them on the computer, I am wondering if they are Purple Martins?  I have attached a few pictures which show them from different angles.  I would appreciate any feedback as to what bird this is.

PS -- since the pictures were not as good as I would have hoped, I went back this morning to see if I could get better ones,  but I was not able to find them again. 

Jeff Parks
Boulder, CO

[Joey Kellner]

Color and overall shape indicate Violet-green Swallow.

Joey Kellner

Littleton, Colorado

[Jim Nelson]

The coloring certainly suggests Violet-green Swallow, but the lack of any green and the odd pattern on the face and the light colored head don’t seem to line up with adult or juvenile Violet-green.  If it weren’t for the violet back color and the fact that the birds are perched, the face suggests White-throated Swift.  Or is it a mix of Tree Swallow and Violet-green Swallow?

 

Jim Nelson

Bethesda, MD

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[Jeff Parks]

Hello all -

I received lots of good comments, thanks to everyone that chimed in. 

My initial confusion on this bird was due to the fact that it showed a different color than any of the swallows I have seen around here, so I was thinking it must be one I hadn't seen yet, even though the Purple Martin is a rare visitor to this part of the country, and the belly was too white for a PUMA based on what I could find out about that species.  Based on the feedback I have received, I suspect it is a Violet Green Swallow, as explained by Christian Nunes:

Iridescent feathers refract light in different ways depending on the angle to the observer. I think that's what's happening here.  This is a female VGSW, so not as dashing as the male. Purple Martins are very scarce breeders on the West Slope, and very rare migrants anywhere east of the Rockies. Tree Swallows breed in Aspen groves at higher elevations, and also sparingly along riparian areas along the base of the Front Range (Boulder Creek and its tributaries support a small breeding population). If you are in the Ponderosa Pine forest, your swallow options are rather limited and the default is VGSW, so that is where to start. Breeding birds in CO tend to morph away from what is depicted in field guides because it's hot and dry here, so they get tattered and worn. This is especially true for species that breed in cavities, since the entrance and egress from these cavities wears heavily on the feathers. A good way to go about bird ID is to address pitfalls like feather wear and iridescence irregularities, and rely upon habitat and range to focus in on the most likely of options. In this way the abnormalities of common birds can be appreciated, and pitfalls like IDing something as a mega rarity or a hybrid can be avoided.

So, thanks to Christian for clearing that up, I am still on the steep part of the learning curve when it comes to birds, but am always happy to learn more details about our feathered friends. 

Happy Birding -

Jeff Parks
Boulder,  CO