I live on southern Vancouver Island, which falls entirely within the recognized range of the northwestern crow. I am curious to hear what people think about identifying Corvus brachyrhynchos caurinus. Now that the northwestern crow is classified as a subspecies of American crow, it can be argued that Corvus brachyrhynchos is always correct… or rather never incorrect. Furthermore, the two are all but impossible to distinguish morphologically—at least that is my understanding.
On the one hand, it’s reasonable to suggest that, if a subspecies can’t be identified with certainty, the correct identification is at species level. But the upshot of that, assuming everyone agreed (which of course they don’t) is that Corvus brachyrhynchos caurinus would effectively not show as existing at all. Which, I’m assuming, it does.
I am curious, too, just how many of the crows I am seeing are actually ssp. caurinus. Some? Most? Virtually all? Virtually none?
We similar issue on East Coast when Fish Crows and American Crows are both present and non-vocal. Technically, we can only ID to genus. If American Crow is only crow in area and you can’t distinguish it from subspecies, then species ID is correct. Perhaps you can only distinguish if bird is in hand.
Those are both good threads.
Best practice for crows would be to include audio for iNat observations where ranges overlap. Northwestern Crows have a lower, huskier voice than (other) American Crows. Similarly, Fish Crows sound quite different from American Crows.
Where the ranges of Chihuahuan Ravens and Common Ravens overlap, I would also encourage audio. For example, I did not manage to get audio for this observation, so I’ve left it at the genus level. Though in photos where the neck feathers are ruffled in a way that allows the observer to capture the base color, audio may not be necessary.
A thread on the Northwest Crow in particular are found here:
Before then, on Vancouver Island, bird lists would have Northwestern Crow instead of American Crow. On Vancouver Island, I think it would be generally accepted to put the now subspecies as your ID - realize though after that it is up to community taxon. Of the 47 American Crow observations I have on Vancouver Island, 25 are to RG subspecies. I have many birds identified to subspecies by others in the community, mostly in southern Africa, that as far as I can tell it is by range - I for the most part leave it and let them have at it.
As I understand the taxa isn’t really identifiable at all - at least not in the field.
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