Date: 11/26/18 4:59 am From: Wayne Hoffman <whoffman...> Subject: [obol] Re: Bean Goose taxonomy
I have now laded in Wilmington.
I worked pretty hard on nailing down the identity of the Nestucca bird, and have some thoughts about this one. Unfortunately
First, I found the illustrations in Dement'ev et al. very useful: drawings of the bills of serratus and middendorffii, as I remember. I divested myself of that multi-volume set before moving. It is a classic ornithological faunistic work covering the whole of the former Soviet Union at the subspecies level. It was translated into English by a program in which the US State Department paid Russian emigres living in Israel to translate numerous scientific works from Russian to English. Translation date is 1967. I imagine the Valley Library has it, or at least access to it.
Second, my understanding of the taxonomic issues are as follows: The research that led the AOU to split the Bean Goose was done in Europe, and the AOU expected the European lists to follow suit. Since then, some molecular genetic work has shown patterns of differentiation not completely concordant with the AOU taxonomy. I think Reeber (mine is still packed) gave a pretty good review of this. However, as I understand it, the most distinctive form genetically was middendorffii. So, if the split is revisited, one possible outcome might be, middendorffii as a separate species and the rest lumped back into Bean Goose, which would still leave North America with 2 species of strays.
Third, the California records committee took years to mke a decision about the Salton Sea bird. To simplify acomplex situation, the head and bill looked good for Taiga, but the overall shape, including quite short neck, was better for Tundra. Howell et al. (Rare birds of north America) concluded that it was Taiga, but the Cal committee eventually settled on Tundra.
Fourth, I would follow Doug's lead, and not put a lot of weight on cistribution of orange on the bill.
Overall, my take on Doug's photos is likely Tundra, but everybody keep taking photos!