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Ideal moon-watching time

It’s that time of year: a late April/early May full moon could provide a nice backdrop for the silhouettes of nocturnal migrants the next couple nights. 
See below for details from Kimball Garrett.
Justyn Stahl
North Park

———- Forwarded message ———
From: Kimball Garrett <kgarrett@…>
Date: Tue, May 5, 2020 at 8:14 PM
Subject: [LACoBirds] Ideal moon-watching time
To: <>

The next three nights, but especially tomorrow (Wednesday) night, should be ideal for moon-watching for nocturnal migrants.  The full moon (a "supermoon" this month) is early Thursday morning, so Wednesday evening should be perfect. It's better to watch a bit before the full moon than after, since the moon will be higher in the sky around 9:00 pm (when nocturnal migrants should be aloft).  Peak spring migration in our area is roughly from 20 April to 10 May, so a full moon the last week of April or first week of May is fortuitous.
Just put your spotting scope on the moon (I usually zoom up to about 40X) and watch for birds flying across the face of the moon. They're surprisingly easy to detect.  You might be able to distinguish "biggish passerines" (e.g, thrushes, grosbeaks, tanagers) from "smallish passerines" (e.g., warblers, buntings, vireos), but it's hopeless to try to identify anything further.  Just counting and getting a sense of the magnitude of movement is fascinating enough.
I suggest that between 9:00 to 10:00 on Wednesday evening (6 May) you give it a try for one or two 10 or 15 minute periods.  Wear sunglasses or use some kind of filter to darken the bright moon or you'll run the risk of at least temporary damage to your eyes. Keep a tally, and make a note of direction of travel.  This is best done by using the moon as a clock face and noting direction by indicating (for example) "6:00 to 12:00" or "4:00 to 9:00."  Using a compass or known orientation, you can later translate that into direction of travel (e.g. "to NW," which seems to be the dominant direction of travel at many local sites). 
If you want, you can report results on this list serve (# of birds per unit time, main direction of travel, your locality, and the time of evening you watched). 
Though you won't be able to identify the birds crossing the face of the moon, you might be able to get a sense of what is moving by listening for nocturnal flight calls.  Some calls (like the "queee?" of Swainson's Thrush) are quite distinctive.  Better yet, make recordings if you can.  There isn't a one to one correspondence between what you hear and what you see flying across the moon (probably not even close), but listening for calls might give you a rough idea of some of the dominant species in the sky.

Kimball L. Garrett

Ornithology Collections Manager
Natural History Museum of Los Angeles County

Source: SanDiegoRegionBirding Latest Reports