HYPERMELANISTIC AMERICAN PIPIT RETURNS TO WINTER IN CENTRAL CALIFORNIA

摘要

On 1 December 2013, I observed a hypermelanistic American Pipit (Anthus rubescens) at Bedwell Bayfront Park in San Mateo County, California (Schneider 2014). This rather striking individual remained there through at least 4 January 2014. Almost a year later, on 5 November 2014,1 found a similar pipit at the same location, where it remained through at least 28 January 2015. The bird was judged by photos to be in its first year when observed in 2013. Photographs of the bird in 2014-2015 again show a rather uniform medium-brown plumage with pale edging on the wing coverts and tertials and a blackish bill and legs, and the shape of the primary coverts, as well as other features of the plumage, made it possible to age the bird then as an adult. As the bird was not captured and banded in winter 2013-2014, it is difficult to prove that the pipit the following winter was in fact the same bird, but the rarity of this plumage abnormality in pipits, the similar overall appearance from one winter to the next, and the same location argue strongly that this was indeed the same bird. The progression in the apparent age of the bird from first year to adult also lends support to this conclusion.