Verification of Unusual
Sight Record
For Utah
Rec. # 2020-01
Common name: |
Parasitic Jaeger |
Scientific name: | Stercorarius parasiticus |
Date: | 10-5-2014 |
Time: | 07:15am |
Length of time observed: | 15 minutes |
Number: | 2 |
Age: | Juvenile and adult |
Sex: | ? |
Location: | Antelope Island Causeway, 2nd bridge |
County: | Davis |
Latilong: | |
Elevation: | 4200ft |
Distance to bird: | 50m at closest approach |
Optical equipment: | 10x50 Nikon Binos, Canon SX50 Digital Camera |
Weather: | Mostly sunny |
Light Conditions: | Good |
Description: Size of bird: | 16in |
(Description:) Basic Shape: | Gull like |
(Description:) Overall Pattern: | overall dark but with paler belly |
(Description:) Bill Type: | |
(Description:)
Field Marks and Identifying Characteristics: |
"Continuing adult and juvenile(both apparent light morphs) from yesterday. I saw
the adult just before dawn, around 7am, flying north of the 2nd bridge a few
hundred meters out. Very distinctive flight,fast and low just above the water.
All blackish-brown upper-side,under-wings and cap, bright white belly. Long
pointed R1 tail feathers. It flew around for about 5 minutes,coming in to about
200m out, then flew southeast until I lost it. About 1/2 hour later, another
Jaerger was seen at the 2nd bridge, but this was more mottled brown so it was a
juvy. It flew much closer,chasing and harassing gulls, very fast falcon like
flight." From my notes taken at the time of the sighting. I did not find either
of these Jaegers, I was just chasing reports that had come over the eBird rare
bird alerts. That fall there were at least 4 different Jaegers that had been
seen near the 2nd bridge of the AIC (see photos) |
Song or call & method of delivery: | none heard |
Behavior: |
Adult, seen flying over causeway heading north, landed briefly on the water but
immediately got up and then circled back around heading SE toward Farmington bay Juvenile-harassing gulls near the marina and 2nd bridge |
Habitat: | Open water of Great Salt Lake |
Similar
species and
how were they eliminated: |
Long-tailed Jaegers are smaller and more delicate, adults have much longer R1
tail feathers, Juveniles have blunt R1 tail feathers, not pointed tail feathers
like the juvenile I saw. Pomarine are larger and more bulky, adults have twisted spoon shaped R1 tail feathers, juveniles are almost unheard of in fall in the western USA, virtually all are dark morphs, unlike the juvenile I saw, and have blunt R1 tail feathers |
Previous
experience with this & similar species: |
Yes, I had seen a Parasitic Jaeger 2 weeks earlier in the same location. However that bird was a juvenile intermediate morph, the juvenile I saw on this morning was a light morph so a different individual. |
References consulted: | Sibley, eBird |
Description from: |
Notes taken at the time of the sighting From photo(s) taken at the time of the sighting |
Observer: | Bryant Olsen |
Observer's address: | 688 East 700 South #105 |
Observer's e-mail address: | ** |
Other observers who independently identified this bird: | Many others had reported seeing these 2 Jaegers. Including Nick and Logan Smith and Steve and Cindy Sommerfeld, Mark Thal and a friend joined me as I was watching the juvenile |
Date prepared: | 1-3-2020 |
Additional material: | Photos |
Additional comments: |
Logan and Nick smith got excellent photos of the adult Parasitic Jaeger,
which can be seen here:
https://ebird.org/checklist/S20064329 My eBird checklist: https://ebird.org/checklist?subID=S20037458 |