Wandering or Gray-tailed Tattler? November, Hawaiian Islands (Kaua`i) (1 Viewer)

[Shorebirdidiot]

I know these two species are very difficult to separate. Any help will be appreciated. I did not hear it call. The two images are of the same bird. Photos are heavily cropped.

 

[Andy Adcock]

Do I recall that shape and or position of the nostril is diagnostic?

 

[Bewick]

For me its a non-breeding wandering tattler-
1. Supercilium does not extend much post ocular- grey-tailed the supercilium extends further post ocular.
2. Yellow at base of lower mandible- on a grey tailed it appears as if that the bill is pale towards the base of the bill
3. A personal observation I made was that it also seems as if non-breeding wandering are darker birds while non-breeding grey-tailed tattlers seem to be paler in comparison.
4 (Edit). Though somewhat difficult to access due to the angle of the shot, it seems as if the length of the nasal grove is also better for a wandering tattler, grey tailed tattler have shorter nasal groves.

Edit- After some further research it seems as if the colouration of the bill can vary.

 

[Shorebirdidiot]

For me its a non-breeding wandering tattler-
1. Supercilium does not extend much post ocular- grey-tailed the supercilium extends further post ocular.
2. Yellow at base of lower mandible- on a grey tailed it appears as if that the bill is pale towards the base of the bill
3. A personal observation I made was that it also seems as if non-breeding wandering are darker birds while non-breeding grey-tailed tattlers seem to be paler in comparison.
4 (Edit). Though somewhat difficult to access due to the angle of the shot, it seems as if the length of the nasal grove is also better for a wandering tattler, grey tailed tattler have shorter nasal groves.

Edit- After some further research it seems as if the colouration of the bill can vary.

Thank you.

 

[Michael Long]

Wandering is also the default species in all the Hawaiian islands