Purple Martin (1 Viewer)

Two groups are usually recognised:

David Sibley says the two groups are:
Eastern: subis
Western: hesperia & arboricola
http://www.sibleyguides.com/flycatchers_wrens.htm

But Cornell (Clements) has:
Northern: subis & arboricola
Desert: hesperia

Which one do you think is more consistent ?

Daniel,

Sibley justifies an east v west grouping thus: "These two populations differ in voice, size, plumage, migration timing, and do not overlap in range".
[And notably, both western forms have pale females.]

Perhaps Cornell’s separation of hesperia alone follows BNA Online’s observation that it is the “Most ecologically distinctive, breeding in giant cacti, especially saguaros (Cereus giganteus), occasionally found away from saguaros during migration”.

Richard

We may know more ... soon:

Moyle, R. G., B. Slikas, et al. (2008).
DNA SEQUENCE ASSESSMENT OF PHYLOGENETIC RELATIONSHIPS AMONG NEW WORLD MARTINS (HIRUNDINIDAE: PROGNE).
Wilson Journal of Ornithology 120: 683–691.

ABSTRACT.—The classification of New World martins (Progne) has a convoluted history because taxonomists have relied on plumage traits that vary continuously across populations. We estimated the phylogeny of Progne by analyzing mitochondrial cytochrome b DNA sequences of 27 individuals of eight of the nine species (10 subspecies) and nuclear beta-brinogen intron 7 sequences of 20 individuals of six species (8 subspecies). The Brown-chested Martin (P. tapera) is sister to other Progne species.
The Middle American taxa—Sinaloa Martin (P. sinaloae), Cuban Martin (P. cryptoleuca), Caribbean Martin (P. dominicensis), and Central American populations of Gray-breasted Martin (P. chalybea)—form a well supported clade. This group is distinct from Purple Martin (P. subis), which has no particularly close relatives. All four Middle American taxa appear to be good species, although Cuban and Caribbean martins could be merged in view of their similar plumage and low genetic divergence (1.2%). Two of the South American taxa, the Peruvian Martin (P. murphyi) and Southern Martin (P. elegans), are also distinct species. We did not examine the Galapagos Martin (P. modesta) for lack of DNA, but it is likely to be a good species as well. An unexpected result of the study was that Gray-breasted Martin appears polyphyletic; its South American populations are closer to the Southern Martin than to its Central American populations.

Daniel Philippe said:

We may know more ... soon

Click to expand...

… or may be not :

In this study, the authors say that P. subis is diverged by an average cytb distance of 5.6% from all other Progne species and there is a clear division between eastern and western subspecies, subis and arboricola, but unfortunately they lacked samples of the third subspecies, hesperia.

Daniel Philippe said:

...We estimated the phylogeny of Progne by analyzing mitochondrial cytochrome b DNA sequences of 27 individuals of eight of the nine species (10 subspecies) and nuclear beta-brinogen intron 7 sequences of 20 individuals of six species (8 subspecies)....

Click to expand...

It's a long time see I did my biology degree but the sample sizes here seem awfully small...?

I'd be curious to know if this is standard in the molecular world these days?

br
Mark

This paper has prompted a bit of 'hrmphing' down in the Southern Cone, with several folk none too impressed.

For anyone reading this with first-hand experience of the genus (and photos?), it would be great if you could contact (the brave) Alexandre Renaudier who is working on an identification workshop for Neotropical Birding magazine. Anyone interested, PM me and I'll send you Alex's email.

cheers

James

If you could send me Alex's email. I myself, only have first hand experience with subis (as they nest in my yard) but I also know of a great gentleman who does lots of great work with arbolicola

Fraser, Stutchbury, Silverio, Kramer, Barrow, Newstead, Mickle, Cousens, Lee, Morrison, Shaheen, Mammenga, Applegate & Tautin (in press). Continent-wide tracking to determine migratory connectivity and tropical habitat associations of a declining aerial insectivore. Proc R Soc B. [abstract] [pdf]

Turner 2004 (HBW 9).

Purple Martin Vocalizations

Nathan Pieplow has a new blog post up about vocalizations of the eastern and western populations of Purple Martin

http://earbirding.com/blog/archives/5365