Sighting Record for Utah

Common name:	Parasitic Jaeger
Scientific name:	Stercorarius parasiticus
Date:	9/4/2024; 9/5/2024
Time:	19:20; 9:00
Length of time observed:	2 minutes; roughly an hou
Number:	1
Age:	Juvenile
Sex:	Unknown
Location:	Shoreline at Lee Creek
County:	Salt Lake Co.
Latilong:	40.790670, -112.165030
Elevation:	~1,300 m
Distance to bird:	~8 m
Optical equipment:	Vortex Diamondback 8x42 binoculars, Vortex Razor HD 85mm spotting scope, Nikon D3500 with 300mm lens.
Weather:	Clear
Light Conditions:	Setting sun; bright and sunny
Description: Size of bird:	A bit smaller than Ring-billed Gull when standing nearby (subject to optical illusion since far away)
(Description:) Basic Shape:	Similar to a gull
(Description:) Overall Pattern:	Dark brown
(Description:) Bill Type:	Hooked, gull-like
(Description:) Field Marks and Identifying Characteristics:	I initially observed a very dark gull-shaped bird with pale bases to the primaries giving the impression of a single flash flying steadily but purposefully across the shoreline. Even though the sun was setting, it was clearly darker than the young California Gulls I had seen. The next observation was with Parker from around 20 m in the daytime with good light. It was standing, where we promptly forgot to note any particular details in our excitement to have refound it. The bird flew and landed a few kilometers out. We observed it in our scopes flying around lazily chasing nothing in particular a few times. It eventually flew back over us, where we got great views and photos, continuing in the opposite direction until we lost it. The following notes are from immediately after the observation, before consulting any references or photos. One underwing flash. Lightly barred undertail coverts but nothing extreme. Noticeable in flight was the compact nature of the bird: an average looking tail, head, chest. Not too lanky, not too bulky. Steady, gull-like flight, no particular chases, but lazy acrobatic flights towards gulls. The following notes are from studying the photos and consulting references: -Intermediate morph Juvenile: dingy dark head, scaly wing coverts, barred and dingy underparts, cinnamon undertail coverts. -Bill: Slim, black nail is only front 1/3 of bill -Head: Seemingly small (almost disproportionately so), streaky, pale malar region, pale nape, overall dark, no obvious dark lores or eye-ring -Underwing pattern: consistent with single flash. Large pale patch on the bases of the primaries. Slight dark notch on P10 (Could suggest LTJA but within variation). Notion of white crescent in greater primary coverts (could suggest POJA but also within variation). -Tail: undertail coverts barred loosely with a cinnamon brown. Average length, not obviously long. Central rectrices pointy, albeit worn. -Primaries: 3-5 pale primary shafts, P7/P6 aren't easily visible, P10-P8 obviously pale. In photos where it appears to be only 2 (P10-P9), remember the wing isn't fully open and the feather shafts are hidden. Can't tell whether primaries are tipped buffy. -Behavior: consistent with PAJA -Size: not a good enough comparison with nearby gulls to tell. (see photos)
Song or call & method of delivery:
Behavior:	Steadily flying across shoreline, occasionally meandering around the other birds. It never made a clear attempt at a chase while we observed it.
Habitat:	Shoreline of Great Salt Lake
Similar species and how were they eliminated:	(Typical) Juvie Pomarine Jaeger: -Bill: Thicker, large gonys -Head: Uniform color, dark malar region, dark lores, pale eye-ring -Underwing pattern: "two flashes" from pale patch at base of primaries and crescent in greater primary coverts -Tail: neatly barred. Central rectrices blunt -Primaries: 3-6 pale primary shafts -Behavior: typically more aggressive, more direct, less "lazy" -Impression: more bulky (Typical) Juvie Long-Tailed Jaeger: -Bill: black nail 1/2 of bill -Head: pale (and body) -Underwing pattern: "one flash" from limited pale patch at base of primaries -Tail: neatly barred and colder colors. Central rectrices rounded -Primaries: 2(ish) pale primary shafts -Behavior: weak tern-like flight -Impression: longer tail
Previous experience with this & similar species:	I've observed both Pomarine and Parasitic Jaegers, but neither at a good distance for study.
References consulted:	Kaufman Advanced Birding, Birds of the World, Sibley Guide to Birds, Julian R. Hough Jaeger Webinar
Description from:	Notes taken at the time of the sighting From photo(s) taken at the time of the sighting
Observer:	Connor Johnson
Observer's address:	1387 N 2050 E Layton, UT 84040
Observer's e-mail address:	**
Other observers who independently identified this bird:	Parker Zabriskie
Date prepared:	9/5/2024
Additional material:	Photos, eBird checklist:
Additional comments:	Amazing study bird, and I feel great for the next time I run into a Jaeger! I wasn't sure how to consolidate both of my sightings, so I put them both here.