Differentiating Grey-tailed Tattler and Wandering Tattler

Learned from this observation: https://www.inaturalist.org/observations/73302509. Also see P34 in Paulson (1986). Identification of juvenile tattlers, and a gray-tailed tattler record from Washington. Western Birds 17: 33-36.

Plumage of both species is very similar. Can look to the bill groove to reliably differentiate the species - "Nasal groove is shorter in Gray-tailed. The deep groove on each side of the bill into which the nostril opens is shorter in Gray-tailed, not reaching one-half the bill length; in Wandering it reaches to somewhat over one-half the bill length."

Wandering Tattlers are also much less common in Australia, and are visitors to NE and N only (visitation to N very rare)

Grey-tailed Tattler (groove <1/2 of bill length):

Image by Malcolm Tattersall from observation https://www.inaturalist.org/observations/73469129

Image by andrewpavlov from observation https://www.inaturalist.org/observations/72352041

Wandering Tattler (groove >1/2 of bill length):

Image by toddburrows from observation https://www.inaturalist.org/observations/70311925

Image by docprt from observation https://www.inaturalist.org/observations/73680449

In noting this, while looking for photo examples in INaturalist there seems to be inconsistency here - i.e. many Research Grade Wandering Tattlers with short grooves and Research Grade Grey-tailed Tattlers with long groves. Please comment if you know why or know of other identifying features to look out for.

Posted on 15 April, 2021 01:07 by tamika_lunn