As far as I know, the variation within species would overwhelm any attempt
to use bill length as an id indicator. Here are the measurements from Pyle
for exposed culmen:
Purple
male 26.8-33.4
female 31.7-38.1
Rock
ptilocnemis (Bering Sea rare to WA)
male 26.9-32.5
female 29.7-38.5
Good luck telling those bills apart :)
Rock
tschuktschorum (the Aleutian one that comes to OR, the other one stays put
but is very close to these measurements)
male 24.5-30.1
female 28.4-34.0
Sorry if my nice table gets chopped up in the ABA view of this email.
Bob Archer
PDX
On Tue, Nov 26, 2019 at 7:08 PM <t4c1x@xxxxxxxx> wrote:
Can someone with experience with both races of Rock Sandpiper and with
Purple Sandpiper tell me if the difference in bill length between both
Purple Sandpiper and Pribilof Rock Sandpiper and Aleutian Rock Sandpiper is
as great as Sibley's illustrations suggest. Is there overlap in culmen
length between the Aleutian Rock and the other two? And is the difference
in bill length a useful characteristic in field identification?
Darrel
