Black-crowned Night Herons that reach the Bering Sea are undoubtedly of old-world origin. The nominate form of this species breeds only as far north as Central Japan. The North American subspecies however is accidental anywhere in the state of Alaska, and breeds no closer to the Bering Sea than extreme Southwest British Columbia. There are a few records of Black-crowned Night-Heron from the Aleutians, and only one Pribilof record. The Saint Paul bird was found on April 3, 1979. Three of the four Aleutian records also come from April, with the fourth record occurring in late May. Often the lakes are still frozen on Saint Paul in April and early May, so a visiting birder on the lookout for Herons in early spring would be wise to find open water. Adults are unmistakable, and the immatures, with their yellow bills and all dark upperparts are also easily identified.