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Hello All,

I had the pleasure of meeting several wonderful birders yesterday at Smithville Res. in Platte Co; Mo. I have long been fascinated by immature jaegers and the associated identification issues. In August of 1977, I traveled to San Diego California to take an over night pelagic trip 162 miles offshore where we observed and photographed numerous jaegers of all three species along with South Polar Skua. Earlier on other pelagic trips and during a 1974 trip to Alaska, I had begun to develop an interest in this complex group. This was about the time that I was introduced to David DeSante and other California birders who were instrumental in my understanding of the Thayer's Gull/ Iceland Gull situation.

Yesterday, September 18th was rather humid but nicely sunny. Nancy Leo and I left Prairie Village arriving first at the Smithville dam. From the Crow's Creek area, located on the east shore of the lake, About 8:30 or 9:00 am the jaeger in question was located sitting about 350 meters nearly due west of the point. It was sufficiently far enough from the dam as to have been invisible given the lighting from that earlier location.

The young jaeger showed a buff colored head appearing lighter at some angles than others. The bill was small and in proportion to the head placed the bird into one of two species- Long-tailed or Parasitic. Many characteristics completely eliminated Pomarine.

The head often appeared to be distinctly smaller and somewhat out of proportion to the rest of the body, especially when the wings and body were in complete side profile view. This is often a strange anomaly but one I have noted on several occasions with Parasitic Jaeger. It is, of course, just one clue in the never-ending mysteries of jaeger ID.

After watching the birds slowly drift in the wind for at least a full hour, while nearly approaching the dam, (the bird then being over 700 yards away from the Crow Creek point) and showing no fear of nearby speed boats, A hunting Osprey changed the dynamic of the situation. 

As Kristi Mayo noted from her observations of the night before, the bird left the water with rapid, deep and powerful wing beats. It took only 21 seconds from take off to cross the nearly 300 yards when the Osprey flared to avoid being hit. After 6 more seconds the Osprey had out powered the jaeger and was safe from further harassment. The jaeger next continued closer toward us before swinging west crossing the entire lake and eventually being lost against the far shore.

The photo of the bird posted on Facebook, brought several things to mind immediately. First was the width of the wing near the junction of the body and the overall width as it continued distally toward the wrist. Second, was how wide the "hand" was even though flared to make a turn, and third the proportions of these parts of the wing. As a final note on the photo - which is totally in silhouette- is the action shown by the head and chest. The bird is lifting the head and showing considerable length and somewhat more bulkiness that one would normally expect for the smaller species in the genus- Long-tailed. This is in preparation for and in the act of beginning a turn.

Plumages in young Parasitic and Long-tailed can be helpful in the identification but this needs to be observed or photographs at much closer distances that what we were able to see. Kristi's notes are very good, but may not eliminate subtle age divisions. So we were left with more subtle overall shapes and physical characteristics which also are expressed in most obvious behavioral ways.

I have the luxury of an extensive HD library of jaegers from several arctic locations to use as a personal reference, and in my opinion this far surpasses anything in any field guide. Mark Land graciously took some time to review a bunch of footage with us and also to share the book- Skuas and Jaegers- by Klaus Malling Olsen and Hans Larsson. Published by Yale University press (1997), and I'd like to thank him for that.

 But to summarize- After extensive review of the flight characteristics from the HD video tape, and comparison with HD records of both Long-tailed and Parasitic- my impressions in the field that the bird was a juvenile Parasitic Jaeger seem to be confirmed. I certainly hope that the boat trip on Monday scheduled can relocate this individual to take some close up photos to confirm in much more detail the characteristics I feel so certain about. Later today, I will capture some of the footage and try to post this either as still frames or as video on Facebook or Vimeo.

This is a fascinating bird that can pull one right into the complexities of identification with gusto!
Enjoy.

Tim Barksdale
Birdman Productions
Choteau, MT and 
Prairie Village, KS

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