This is about a previously mentioned sleep-deprived encounter with an adult Golden-Plover. While I'm pretty sure it's an American Golden-Plover, I felt like the though process was worth sharing.
Photos by Max Segler
Step #1 in finding an interesting bird: notice something seems "different". There was a flock of juv Am. Golden-Plover flying around the beach for a period of time, but this bird never joined them.
Some listed features of Pacific Golden-Plover include a long bill and long legs. Per points #1 and 2 above, from a distance, I thought they looked pretty long. The distribution of white and black on the belly, while heavily in molt, sure didn't look *wrong* for Pacific Golden-Plover either (the broad white band, #3).
I'll admit, I wasn't terribly excited, but it was worthy of further investigation.
If point blank views were possible, I would have been able to see more critical details. Per above, the red lines show the length of the tertials vs. the tail tip. In Pacific, they're nearly the same. In American, the tertial tips are much closer to the body than the tail tip. The amount of primary tips visible (blue lines) averages a shorter/smaller amount visible. Combine these features and it makes for a unique "back end". I also feel like fresh Pacific Golden-Plovers have a slightly different hue of "gold" on fresh feathers vs. American (yellow line) - but this is likely far less definitive.
I held out hoping for a flush - perhaps some photos, and a chance to look at those feet. Pacific Golden-Plovers are reported to have their toes extend past the tail tip, whereas American do not.
While I didn't get any more pictures of my own, Max did (per above), and I watched the bird fly in my scope.
The toes peek past the tail tip. Honestly, it's not much different than the one flight photo of the first Ontario record. Alas, it's also not that much different than other reference media of American Golden-Plovers... Turns out those toes might be one of those features where there is overlap between the species, at least depending on photo angle / posture etc. Some images of Pacific really do show crazy long toes, which is interesting, right up until you have a bird like this! Ahh!
We never did get a clear view of the critical "back end" details. What is visible in the photos suggests American Golden-Plover to me. It seems the tertials and tail tips are well offset (red), and it does look like there is a lot of primary tip showing (blue).
No matter what, it was another fun chance for some solid bird study.
While I'm not a fan of just reiterating known ID criteria, I do think there is some value in sharing field experiences. Even more so, I can't stress how much easier it is to really learn and appreciate these published ID features, when you have a real life bird to look at. Can you *see* how long the toes are in flight? Or do you need pictures in order to tell? ... How visible are the tertials & tail tip at a distance? How much overlap, or how reliable, are some of these published field marks?
From Max - after this was written (!!) :
ReplyDeleteHave you noticed PGPL having a thicker/more BBPL esque bill vs AMGP? I remember looking through Macaulay and noticing that, although I’m not sure if it legit.
Based on what I’m seeing, our bird would have more AMGP bill thickness