Bank Swallows or Pale Sand Martins? Guangxi, China (1 Viewer)

[Barbets48]

Recently observed large numbers of brown swallows feeding over a freshwater marsh in Guangxi, China. Uncertain whether they are Bank Swallows or Pale Sand Martins, and according to the ID guides the two are distinguished based on clarity/definition of breast band and overall darker color brown in Bank Swallow. This has been difficult for me to judge, so submitting some (distant) photos here for help, for those who are more familiar with these species.

Mike

 

[Steve Lister]

I have never convinced myself I have seen Pale Martins on any of my Asian trips, despite being in the right places at the right times. I think I would need to see both species together to be sure. Can't say either way from your photos, sorry.

 

[Barbets48]

Does anyone else have any suggestions for how to separate these two species?

 

[MacNara]

I've never seen Pale Sand Martin, but looking at books and the internet, I can't see any easy signs that would visually separate them from Bank Swallows; and a fortiori I think it would be impossible on the basis of your photos.

However, Birds of the World online shows Pale Sand Martin wintering in Guangxi, but Bank Swallow not wintering anywhere in China - maps attached (I hope this counts as 'fair use'). Since it shouldn't be the migration season, at the moment, these should be Pale SM. However, I am not sure that this is reliable information - Mark Brazil's 'Birds of East Asia' shows Bank Swallow wintering along the Chinese coast in Zhejiang and Fujian (and this book doesn't go as far west as Guangxi).