As usual, I must second Ted's thoughts. Nasty is right about this
complex - Mike Lanzone and I recorded flight calls of Black-headed
Grosbeak, Western Tanager and Bullock's Oriole in Arizona in 2005, and
the variation was staggering. On subsequent (and previous actually)
trips to the SW, I record
Good stuff, Andrew!
A few things:
1. "Ted's clips" of Brewer's Sparrows are actually Nathan Pieplow's.
2. Interesting to compare Andrew's observations in Catron County, NM,
with observations from "up north" in Colorado. Pretty convergent, on the
whole, I would say.
3. Andrew says "presumed" Bul