Orange-crowned Warbler Subspecies Identification
Orange-crowned Warblers (Oreothylpis celata) are a member of the wood-warbler family (Parulidae), and breed across Canada and the northern United States. Four subspecies are recognized, three of which are found in British Columbia. The identification of Orange-crowned Warbler subspecies may seem daunting, however, with experience the separation of O. c. lutescens from the other two subspecies in British Columbia is fairly straightforward. This article will deal primarily with the identification of O. c. lutescens, O. c. orestra, and O. c. celata.
Although O. c. celata is extremely similar to O. c. orestra, and most individuals likely cannot be identified safely in the field.
O. c. lutescens – Breeds along the Pacific coast from Alaska to California, and winters from southwestern British Columbia to western Mexico. In British Columbia it can be found west of the Coast Mountains and adjacent islands, including Haida Gwaii.
O. c. orestra – Breeds from the southern Yukon through the Rocky Mountains to the southern United States. Most spend the winter from southern California south through western Mexico, although some have been found in southern British Columbia through the early winter. It breeds across the entire interior of British Columbia, from east side of the Coast Mountains to the east side of the Rocky Mountains, and in migration it may be found in small numbers west of the Coast Mountains.
O. c. celata – Breeds across the boreal forest from Alaska to Labrador, and in British Columbia it is found east of the Rocky Mountains in the Peace River/Fort Nelson lowlands. Winters from the southeastern United States through eastern Mexico and into Central America. A few may be found away from northeastern British Columbia in migration.
O. c. lutescens is typically the first to arrive in spring in BC, with the first most individuals arriving in April, while O. c. orestra/celata migrate through in mostly in May. During fall migration there appears to be considerable overlap between O. c. lutescens and O. c. orestra/celata and more work may be needed to further determine migration timing. Most over-wintering birds in southwestern British Columbia are O. c. lutescens, but some O. c. orestra or O. c. celata may also attempt to winter, although these birds may be found anywhere across southern British Columbia.