Date: 2/27/17 6:07 am From: Phil Jeffrey <phil.jeffrey...> Subject: Re: [AZNMbirds] Sam Lena Waterthrush Follow-up
:: they essentially occur along rivers and streams with running water
As an East Coast birder who sees both waterthrushes each year, I'd like to chip in on this. We see Louisianas next to still water including muddy puddles a significant proportion of the time in Central Park (NYC) on migration and I've seen them in TX in the same context. I would not use this as an ID factor. Northerns are probably more prone to wander away from water - wet lawns and shaded cover, but that's also biased by Northerns being significantly more frequent through NYC.
Amongst the other factors people have listed - which all seem reasonable to me - I haven't seen mention of one that may be useful - Northern bobs in a different way than Louisiana waggles. Northern bobs mostly it's tail with relatively little movement of the body beyond (head-side) the legs, closer to Palm or Prairie: https://www.youtube.com/watch?v=VcoF12ILFEw - this bird also being useful as a pale NOWA for ID comparisons
In contrast a Louisiana is much more articulated, and the legs bob as well, with the whole body rotating about an axis in the breast. Really only the head remains still. https://www.youtube.com/watch?v=Y4I7ZTzywIc I didn't pick this one because the LOWA was feeding in still water, but it conveniently does go back to my original point.
I use the motion as one of my ID criteria, behind supercilium and flank contrast, leg color (spring only), call note and streaking density/shape.
Cheers Phil Jeffrey Princeton NJ
On Sun, Feb 26, 2017 at 2:48 PM, Gary Rosenberg <ghrosenberg...> wrote:
> Thanks Chris for your detailed analysis. One other factor I would mention > is habitat. I don't want to say "never", but I ca not think of a single > LOWA record from AZ from a pond - they essentially occur along rivers and > streams with running water. This is also true for them wintering in the > Tropics. Given that this bird was at a small pond with a mud edge should > have made people question the ID. > > Gary > > Sent from my iPhone > > Home Page: https://list.arizona.edu/sympa/info/aznmbirds > To unsubscribe use the Unsubscribe button on that page. > To view archive: click "Archive" on that page. >
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