[birding] Identifying flying Band-tailed Pigeons vs. Eurasian Collared-Doves

[Matthew]

Hi Birders,

Now that Eurasian Collared-Doves have conquered Silverton I am having to 
leave many flyby Pigeons/Doves unidentified.  Before the Collared-Doves 
showed up it was pretty easy to identify flyby pigeons/dove:  Mourning Dove; 
small with pointed tail,  Rock Pigeon; fat with a white rump and under-wing 
and very distinctive flight pattern, Band-tailed Pigeon;  large with 
relatively plain plumage and fast direct flight.  When Eurasian 
Collared-Doves showed up the Mourning Dove and Rock Pigeon were still easy 
to I.D. but separating flying Band-tailed Pigeons from flying Eurasian 
Collared-Doves became a challenge.  At first glance one would think the two 
easy to separate but a distant flying Eurasian Collared-Dove/Band-tailed 
Pigeon looks relatively similar.  Both have a similar shape, dark flight 
feathers that contrast against the paler greater and median coverts, the 
greater and median coverts are also paler than the lesser coverts so there 
is a paler line of feathers between the flight feathers and lesser coverts, 
and they both have a pale tip to the tail.  It is also hard to judge the 
size and judge between buff and gray when the bird is distant and flying 
against a blue sky.  I think I have notice a difference in flight style 
between the two.  Band-tailed Pigeons seem to flap their wings more from the 
wrist and Eurasian Collared-Doves tend to fly more from the shoulder, but I 
do not know how reliable this characteristic is.  Any thoughts?

Matthew Schneider
Silverton, Oregon
gaviaimmer at live.com