National Audubon Society Birds of North America: A Guide Review
10,000 Birds
JUNE 1, 2021
Interestingly, Chestnut-collared Longspur does appear under its brand-new official name, Thick-billed Longspur, though the description underneath uses the old name. I like my field guides to have clearly stated taxonomic guidelines in the Introduction, even if it includes a page of exceptions, and a cut-off date.
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