Santa Cruz River near Tumacacori, 29 Nov 2008

Jake Mohlmann and I took a walk down the Santa Cruz River near the town of Carmen on Saturday. The only truly rare bird was an adult female BULLOCK'S ORIOLE. Of course this bird is a relatively common summer breeder, but finding one in November is highly unusual. The quality of the pictures is fair at best, but diagnostic.

Note that the yellow coloration in the above picture is brighest on in the malar region, which is fairly distinctive of female Bullock's. I'm calling this an adult because the yellow head and upper breast coloration was brighter than I would expect in hatch-year birds, but sometimes it can be difficult. (Anyone out there with experience banding this species? It may be difficult to tell from the pictures alone.)

Also note the upper wingbar, which is formed by the buffy whitish tips of the greater coverts. If you click on the picture to enlarge it, you can also see what appears to be a row of tiny dark spurs cutting into the upper edge of the wingbar. I find this mark to be very helpful when you can't get a great look at the head pattern/color - for example, when blocked by leaves or branches. Compared with the smoother upper edge of the wingbar shown by female or immature male Baltimore Orioles, it's a fairly distinct field mark. Not that one should expect to find a Baltimore Oriole in Arizona in any season, but a nice adult male was found in Tubac earlier this year! So it helps to weigh all options.

All of these images were captured on a simple Canon Powershot S5 with a 1.5x lens adapter (rendering it effectively an 18x optical zoom).

An unusual morning mist shrouded the peaks of the Tumacacori Mountains immediately west of the river; very scenic. The riparian habitat still has a lot of cottonwoods and other native vegetation, but much of the old-growth cottonwoods and willows are gone. Cattle have tromped down much of the grasses and herbaceous growth, but there are still plenty of places for birds to hide.

Another neat find was a row of 10 White-winged Doves perched along a telephone wire in the tiny town of Carmen (just north of Tumacacori). Most of the White-winged Doves that are so ubiquitous in Arizona during the breeding season head farther south, but small concentrations of the species are sticking around more and more frequently during the winter, especially in towns along or near the Santa Cruz River.

We didn't find much later in the morning at Santa Gertrudis Lane, but there was a nice Northern Cardinal perched strikingly amongst the red pyracantha berries. There are bunches of these and other berries (hackberry, elderberry) all along the lane, and it is always worth checking to see if concentrations of fruit-eating species like Cedar Waxwings, American Robins (or the much more rare Rufous-backed Robin!) are attracted to this spot. The only thrush we found was a skulking Hermit Thrush.

Plenty of good winter birding to be had in southeastern Arizona...can't wait for the Christmas Bird Count season to start!

Good birding,
John Yerger

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