NOTEWORTHY WATERBIRD RECORDS IN THE DELTA OF THE RIO COLORADO, MEXICO, 2002

Abstract

Surveys of the Río Colorado delta in summer 2002 revealed abandonment of one large heronry but the existence of another large and several small, inconspicuous heronries previously nonexistent or undetected. Most notable among these mixed-species colonies were two nests of the Tricolored Heron and two fledglings of the Reddish Egret, representing considerable northward extensions of these species’ breeding ranges.