[Tweeters] last chance for Northwestern Crows!

Gary Bletsch garybletsch at yahoo.com
Mon Aug 16 09:17:42 PDT 2021

Dear Tweeters,
If I am not mistaken, a taxonomic update on eBird will take place starting tomorrow. Many if not most birders will pick up a few armchair lifers, although I don't think there will be as many splits as there were last year. We will have to put up with a ridiculous new name for the Mew Gull, but if we've birded in Eurasia, we'll pick up a species with that split. If we've seen a Sedge Wren down in South America, assuming that we've seen one in the USA, we'll pick up a species there, too, since those Sedge Wrens down in Ecuador will now be Grass Wrens. 
The taxonomists have also decided, among other things, that the Northwestern Crow must be lumped with the American Crow. This is a section of our lists where we'll lose a species, but the lumps are far outnumbered by the splits, so almost everyone's life list will have a net gain after the update.
Here is a fun exercise that one may do with a computer. Go to eBird, then Explore, then Species Maps. Type in Northwestern Crow for the species, and voila! You get a nice map of the species distribution. If you click the little box on the right, "Show Points Sooner," that will give you a more precise map that shows each spot where the Northwestern Crow has been reported.
At this point, I'd take a screen shot and save it. Now you will be able to look back at this map sometime in the future. In a day or two, if you were to go on eBird and try the same thing, you will presumably have a different-looking map, since the two species will have been lumped. 
There are all sorts of interesting details in the map for the Northwestern Crow. For example, zooming in to our part of the world, Western Washington, you will see that there are zero pinpoints for this species in Skagit County, Snohomish County, or King County. I think the same can be said for Kitsap, Mason, Pierce, Thurston, Cowlitz, Clark, Wahkiakum, Lewis, and Skamania.
It would be absurd to expect any bird, even as smart a bird as a crow, to understand county boundaries. The lack of Northwestern Crow  sightings in those counties has nothing to do with the birds themselves, and everything to do with decisions made by birders, and especially by the eBird editors, as to where one should count Northwestern Crows, and where one should count American Crows. This leads to oddities, such as the Northwestern Crow making it all the way across Island County's Camano Island, to the western end of the Mark Clark Bridge--actually, to the western end of the new bridge that has replaced the Mark Clark Bridge, the name of which escapes me. Crows are free to fly eastwards across the narrow waterway here, taking them to Leque Island, Eide Road, and Stanwood. However, once the birds make this journey, their name changes to American Crow!
The same thing happens at such places as Guemes Island, Larrabee State Park, and Leadbetter Point. 
Another fun exercise that one can do right now is to call up the same map, only for the American Crow. If one zooms in to the boundary of Whatcom County and British Columbia, the same oddity arises. There are all sorts of colorful little dots on the Washington side of the line, but just a plain, birdless map on the Canadian side. Nary an American Crow does one see north of that international border! Of course, this is just another artifact of the human constructs involved. The eBird editors up there decided quite a while back that all of their crows are Northwesterns. 
Caw, caw, caw...I for one am looking forward to this particular lump! 
Yours truly,
Gary Bletsch

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