Sighting Record for Utah

Common name:	Buff-breasted Sandpiper
Scientific name:	Tryngites subruficollis
Date:	9/2/16
Time:	8:45 am
Length of time observed:	30 minutes
Number:	1
Age:	**Adult
Sex:	?
Location:	Utah Lake State Park
County:	Utah
Latilong:	40.236843, -111.743233
Elevation:
Distance to bird:	Flew by with a group of peeps at less than 25 yards. First saw the bird on the mudflats at close to 75 yards and later at over 150.
Optical equipment:	Swarovski 20X60 Spotting Scope, Nikon Monarchs 10X42 Binoculars, Iphone 5S (digiscoped photos).
Weather:	Not unbearably windy like the previous day. Calm conditions, slightly cloudy.
Light Conditions:	Perfect morning light.
Description: Size of bird:	Slightly smaller than Killdeer. Bigger than nearby Baird's, Least, and Western Sandpipers.
(Description:) Basic Shape:	Body was sandpiper/plover like. Small head. Appeared longer-winged in flight compared to other peeps.
(Description:) Overall Pattern:	Very buffy-colored overall. Black pattern on back was very noticeable. Clean, unmarked face.
(Description:) Bill Type:	The bill was short, straight, and thin.
(Description:) Field Marks and Identifying Characteristics:	[on 1 Sep]: First noted the bird with its back facing me on mudflats around 75 yards away and immediately recognized it as something different. Overall the bird was very buffy-colored with black scaly feathers on the back. This pattern really stood out through the scope. The bird also showed an unmarked, buffy face with cap. Bill was very thin, short and straight. Yellow legs. There was no streaking or breast band on the chest. When observed in flight I was able to see the black crescent on an otherwise pale underwing. This alone should be a clinching field mark. Size: Noticeably bigger than nearby peeps (Western, Baird's, Least). Roughly the same size as Pectoral, but slightly smaller than Killdeer. [on 2 Sep] The Buff-breasted Sandpiper was refound the morning of September 2 with 7 other birders. It was viewed in much better lighting and weather conditions. We all had great looks through the scope as it foraged on the mudflats with other sandpipers getting great comparisons with Baird's and Pectoral Sandpipers. Better photos were also obtained. (see photos)
Song or call & method of delivery:	Did not hear any vocalizations.
Behavior:	Seemed rather skittish. I first saw it in the scope at about 75 yards with its back facing me. I then kept it in the scope as it flew back another 15-20 yards until landing on the mudflats. It picked up and flew once more landing beyond the line of rocks extending into the lake. Then all of the peeps were startled by a plane landing at the Provo Airport Dike and took off. As the majority of the birds came back and resumed feeding, I scanned the flocks several times without any luck. Then to the west a small flock of 5 sandpipers flew by heading south towards the mudflats. Following right behind, a larger flock of peeps flew in. I put the scope on these birds and was able to pick out the Buff-breasted very easily, which later peeled off from the rest of the group and made several passes around the mudflats by itself. The light, overall coloring, pale underwings (with black crescent), and Wing/body shape really stood out.
Habitat:	Mudflats/shortgrass vegetation.
Similar species and how were they eliminated:	Pectoral Sandpiper: The Buff-breasted was seen in close proximity to at least a couple of Pectoral Sandpipers. First, the black speckling on a buffy colored back was very different. The Pectorals showed a more reddish/brown back, with a different scapular pattern. I also noticed they usually have two light colored lines running down the back, which was not present on this bird. There was no sign of the characteristic streaked breast band that a Pectoral would show. Body shape was also off. Unlike the Pectorals equipped with a slightly longer, droopy bill, this birds bill was thin, short, and straight. Baird's Sandpiper: Baird's Sandpipers have black legs as well as a streaky breast band. Baird's are also noticeably smaller than killdeer and not nearly as buffy as this bird was. Ruff: Size was the biggest factor in eliminating rough. Bird was slightly smaller than a killdeer.
Previous experience with this & similar species:	No experience with Buff-breasted Sandpiper in person. Just lots of study in field guides as well as online resources and videos.
References consulted:	National Geographic Field Guide to the Birds of North America, The Sibley Guide to Birds.
Description from:	From memory
Observer:	Kendall Watkins
Observer's address:	2622 W Dry Creek Drive, Riverton, Utah
Observer's e-mail address:	*e
Other observers who independently identified this bird:	[on 1 Sep]: Joellen Herbert. [on2 Sep]: Jack Binch, Merrill Webb, Samantha Phillips, Carol Jean Nelson, Larry Draper.
Date prepared:	September 1, 2016 with additions on 9/3/16
Additional material:	Photos
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