Santa Cruz Flats, Pinal County, AZ

Thursday, July 20, 2017
Desert birding in our summer months calls for early rising. Usually, I look for shady (using the term loosely) locations, but today, it was a potential beast: Santa Cruz Flats, extending south of Eloy all the way to the Santa Cruz River — a great expanse of open land between the Sawtooth Mountains (west) and Picacho Peak (east).

Who would even think of going out there in mid-July?? Well, Dr. Dave Pearson (ASU) noticed it was an under-birded area and when he discovered 44 TROPICAL KINGBIRDS (or more) in early June, he decided to follow up to discover if there might be fledglings. Lois Lorenz, Kathe Anderson and I joined him on his search.

Did I mention the active monsoon season we’ve been enjoying? Not only does it bring humidity, but this year, lots of thundershowers and extended rainfall. With only a few paved roads through the Flats, the dusty dirt roads might just be a slip and slide mud experience. So, I was thinking the trip might be short-lived.

Stopping first at Arizona City Lake, we began our bird count for the day with thirty-one (31) waterfowl and desert species in half an hour (5:30-6:00 a.m.)

Although we had rain the previous night in the East Valley (Phoenix), the dirt roads within the Flats were dry — but not dusty. Sweet! Not even mud puddles!

SWAINSON’S HAWK (9), both adult and immature, at various locations, often perched in the fields. This immature was really far out in the field but still easier for me to try to photograph than one flying overhead.

We saw more BLUE GROSBEAK on overhead wires than in trees or on the ground.
In the most arid areas, we had some good desert birds including GREATER ROADRUNNER, BELL'S VIREO, BLACK-TAILED GNATCATCHER, and LUCY'S WARBLER.
Along with the usual assortment of blackbirds (GREAT-TAILED GRACKLE, BROWN-HEADED COWBIRD, RED-WINGED and YELLOW-HEADED BLACKBIRDS), a BULLOCK'S and HOODED ORIOLE were present.
In six hours of birding, I need not list each bird we spotted, but the BURROWING OWLs always steal the show.

Our main purpose at the Flats was to determine if the TROPICAL KINGBIRDs had fledged any young. This is a bit farther north than TRKI are usually found and to be in such great numbers is mind-boggling. I'm lucky if I find one or two per year in the southern areas of the state.

What we found was that the TROPICAL KINGBIRD (24 counted) has a nifty song (trill) and a trill of a call, too. When we came upon its trees, one would fly out and over us before circling back down into the leafy pecan trees (on various roads). So, we could surmise that nesting was ongoing. The trill is short, sweet and catchy.

Note its gray head; pale throat and cheek. Upper breast is actually olive but sunlight is washing it out as it fades into yellow on the rest of its underparts. Wings and tail are brownish black with thin whitish edges on the tail feathers. Tail is slightly notched, not squared as in Western Kingbird. And, look at the size of the bill!  It is longer than or equal to its lore+eye. In Western Kingbird, the size of the bill is the size of the lore. And, not seen in the photo, the back of the TRKI is grayish washed with olive-green, not the pale gray back of the Western.

The bird sets itself apart from the WESTERN KINGBIRDs (18) both by song and by appearance.

WESTERN KINGBIRD - with wide white outer tail feathers
Another bird had us scratching our heads. The CLIFF SWALLOW. We've all seen CLIFF SWALLOWs that nest under bridges and fly out over bodies of water or fields with insects. But CLIFF SWALLOWs foraging on the turf of the various turf farms within the Flats? Interesting! 
Series of 3 photos of CLIFF SWALLOWS foraging at the Turf Farms

Dr. Pearson provided a conservative estimate for eBird of 2500 CLIFF SWALLOW.

Not only was it a day to remember with our 66 species count for the day, (4 separate eBird locations), it begged to be repeated. Will the nesting TROPICAL KINGBIRDS have young by next week?  Or, later?  Generally, the species migrates out of southern Arizona by the end of July up until September, so there is still time to check out the TRKI again before they take off for the more southern Americas.

R-L: Dave Pearson, Lois Lorenz and Kathe Anderson

* * *

1 comment:

  1. Very daring!!! I've done this trek only once in the summer and it And that's to put it mildly:)