Verification of Unusual Sight Record
For Utah

Rec. # 2020-38

Common name:

Parasitic Jaeger

Scientific name: Stercorarius parasiticus
Date: 10 Sept 2020
Time: 19:06
Length of time observed: 15 minutes
Number: 1
Age: Juvenile
Sex: Unknown
Location: Sand Hollow State Park
County: Washington
Latilong: 37.101379, -113.374115
Elevation: Approx 3000ft
Distance to bird: 40m
Optical equipment: 8x42 binoculars, Sigma 150-500mm lens on Nikon DSLR
Weather: High 70s, clear skies, calm
Light Conditions: Well lit by setting sun
Description:        Size of bird: The size of a small gull, impression was about a 15 inch body length.
(Description:)       Basic Shape: Gull/jaeger
(Description:)  Overall Pattern: Plain, very dark brown overall
(Description:)            Bill Type: Small, thin and straight. Culmen curves down at the very end.
Field Marks and
Identifying Characteristics:

Seen while walking down from the park ring road where we parked on the shoulder. A dark silhouette, similar in size and shape to Ring-billed Gulls which were also present. Slightly smaller-headed and shorter-legged than Ring-billed Gull, and more barrel-chested. Bird was stationary. Upon getting closer, the plumage was well-lit and we could see it was a uniform deep dark brown, almost black. Brown was cool toned with hints of gray. Photos taken reveal some very faint lighter brown edging on the feathers. Eye was dark, basically blending in with the plumage. Legs pale grey. Bill small thin and straight, gray with a dark tip, where the culmen curved down. Wings long and pointed, protruding past the tail.
(see photos)

Song or call & method of delivery: Silent
Behavior: Awake, but still. Looking around, but fairly undisturbed by our presence.
Habitat: Lake shore at water's edge, standing amongst washed up and dried weedy grass.
Similar species and how
were they eliminated:
Wrong body and bill shape for Black Tern and other dark tern/noddy type birds. The structure was more like a gull. Separated from Heermann's Gull, the only gull with plumage this dark, by bill size and coloration. Separated from Pomarine Jaeger by bill weight, and lack of pale barring on undertail. Separated from Long-tailed Jaeger by lack of pale whitish feather edging over upperparts. Separated from adult Parasitic Jaeger by presence of darker bill tip, and faint light brown feather edging.
Previous experience with
this & similar species:
This species is a regular fall migrant and occasionally overwinters where I live in Santa Cruz, California, and I have seen both this and Pomarine Jaegers before both during scope seawatch and on a pelagic
References consulted: Sibley Field Guide, Cornell Lab photos
Description from: Notes made later
From photo(s) taken at the time of the sighting
Observer: Liam Murphy, Giulia Donato
Observer's address: 175 18th Ave, Santa Cruz, CA 95062
Observer's e-mail address: **
Other observers who independently identified this bird: Seen the following day by Maurice DeMille, as well as Kevin, Pamela, and Everett Wheeler per eBird observations. Also seen the following day by Mike Schijf, eBird reviewer, who informed me via email.
Date prepared: 12 Sept 2020
Additional material: Photos
Additional comments: Photos emailed to submittal address