Date: 11/15/18 1:58 pm From: Derb Carter <derbc...> Subject: RE: Cullowhee martin
So much for measuring by photographs. That could change things. Below are listed reported wing chord measurements in Birds of North and Middle America (or Neotropical Birds Online if not in the former) in order for males and females of each species (longest avg to shortest with reported range).
Male Purple 146.3 139-153
Male Carib 143.5 134-149
Male Cuban 142.5 140-145
Female Purple 142.3 136-147
Female Cuban 140.0
Female Carib 140.0 135.5-148
MaleSinaloa 136.7 136-138
From these measurements, Sinaloa is obviously back in play. Wing chord is below the average of all three species (no measurements for female Sinaloa), very close to male Sinaloa (would expect female to be slightly shorter), and actually shorter than all reported measurements for Caribbean or Cuban except one male Caribbean. Also very close to shortest female Caribbean and no range reported for female Cuban. But 135 is notably below the averages for Cuban and Caribbean.
From: Jeremy Hyman [mailto:<jhyman...>]
Sent: Thursday, November 15, 2018 3:50 PM
To: <carolinabirds...>; Derb Carter
Subject: Re: Cullowhee martin
The wing chord of the bird is 135mm. Let me know if anyone wants to know any other measurements or see other photos. I think it will be a few days before someone from the museum picks it up.
I have a fair amount of experience with all the Progne martins in the Americas, except Galapagos. I think the bird found, photographed, and posted in the CBC gallery is almost certainly either a Cuban, Caribbean, or Sinaloa Martin, any of which would be an extraordinary record. Female plumages of these species are very similar. My limited experience with Sinaloa was years ago when it was considered a subspecies of Purple. Sinaloa is quite rare within its range in western Mexico, which is much more remote from western NC. It is smaller than the other two. This is imprecise from the photos, but my estimate of the wing chord in the specimen is 142-143 mm which is outside the reported range for Sinaloa of 136-138 mm, and within the range 134-149 and close to the mean 143.5 of Caribbean (I could not find measurements for Cuban).
I compared the posted photos to some photos I took of Cuban Martins on recent trips and it is generally identical to some in the photos. This does not, however, eliminate Caribbean because in female plumage it is essentially identical to Cuban (male Caribbeans are white below; male Cubans solid blue/purple). I checked some references that say the white below is more restricted on Caribbean than on Cuban, but in looking at photos of both species I really see little difference. One thing I did notice in photos of each species is the undertail covert of female Caribbean is always pure white, while the undertail covert of many but not all Cuban seems to have a few dark feathers. I have not seen this mentioned in guides. The Cullowhee bird has a pure white undertail.
Hopefully further investigation will reveal the identification, but my guess from the photos is either Caribbean or Cuban.