The lessons of Catharus thrushes revisited
I discuss morphological variation in United States Catharus thrushes with regard to in-hand and field identification, particularly in the Veery (C. fuscescens) and in the Gray-cheeked Thrush (C. minimus). Geographic variation in all United States Catharus is significant, creating a substantial identification challenge. Three subspecies especially are sufficiently similar to warrant caution: C. fuscescens salicicolus, C. m. minimus, and C. ustulatus swainsoni. As an example, I reidentified a specimen reported to be a salicicolus Veery and determined it to be instead a nominate Gray-cheeked Thrush. Ample recent specimens of Catharus in fresh plumage are needed to further elucidate geographic variation within the thrushes in this genus. Attempts at field identification of some forms should be made with the utmost care, and demand proper, thorough documentation.