more ravens and crows


Eric Johnson <e.johnson31@...>
 

FYI, here is what I have been able to figure out about raven/crow distribution in Calif. It works most of the
time! Ravens occur in the more arid climates (Calif. deserts) as well as the Sierra (conifers). Crows occur in the
more mesic climates of the central and north coast, and in the central valley. Coastal San Diego County has, to
my recollection, only ravens (arid). They co-occur where the redwood and doug fir (conifers) occupy a mesic
climate (coastal Marin, Mendocino, etc.). Why? Who knows! Ravens seem ro be adapted to the places crows
don't like. Are crows competitively excluding ravens from the milder climates? Anyone know of places where
crows have displaced ravens (or vice versa)? Maybe we need to look at the north cost in a century or so!

Eric J.

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