Date: 10/30/20 4:43 pm
From: Russ Namitz <namitzr...>
Subject: [obol] Re: California vs Woodhouse's Scrub-Jays in OR/NV/CA
Hey Joel~

I took a shot across the bow at our Nevada neighbors and for that I publicly apologize. I did not mean to cast aspersions on the birding skills of those observers. I know that you personally are familiar with some of them.

However, birding by geography is one of the very foundations of bird ID; it is something that is taken into consideration, rightly so, wherever one birds. Using geography alone is a slippery slope, and like much of bird ID, other variables should be taken into consideration.

Of the 19 Woodhouse's Scrub-Jay eBird reports from NW Nevada that are roughly within 50 miles to the Oregon border that you provided (thank you btw), only 6 reports occurred after the 2016 split of Western Scrub-Jay into California and Woodhouse's, and only 3 of those provide any sort of ID comments.

So of the 12 pre-2016 split, none have any comments of scrub-jay ID, most detections are from stationary counts and almost half of those are from stationary point counts. A quick note about the Great Basin Bird Observatory (GBBO) point counts: these reports have 2 counts for each day with different times and species lists, so there are 10 detections there, not five, though almost certainly the same individual(s).

What that means is that this data collection and bird identification took place when Western Scrub-Jay was still a single species. I suspect that observers were not paying as close attention to differentiate subspecies ID details, especially on stationary point counts where the vast majority of bird species are typically "heard only."

To me, this suggests that A) Woodhouse's Scrub-Jay is the default scrub-jay species in eBird for those NW Nevada Counties (Washoe, Humboldt, Elko) and does not get flagged as a rarity, and B) eBird perhaps included NW Nevada in the assumed geographic range of Woodhouse's Scrub-Jay when updating the 2016 split which automatically switched all of the "Western Scrub-Jay" detections in the database to "Woodhouse's Scrub-Jay."

My real point in responding to Bob's post is that I believe that the eBird filters of those NW Nevada Counties should be set to zero for Woodhouse's Scrub-Jay, prompting users to write identification comments at the very least.

Cheers,
Russ Namitz



 
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