Orange-crowned Warbler

Late Fall Warbler

Orange-crowned Warbler [Mark Morse Photo]

The Orange-crowned Warbler Oreothlypis celata is most commonly seen here in the fall.  That is because it is late coming from its breeding grounds and is seen here most commonly after most of our warblers have migrated south.  It breeds in northern Canada below the tree line and in the mountainous areas of western US.  It winters in the southern US and Mexico.  

The Orange-crowned Warbler is a small warbler, 12 cm (4.75-5 in) long.  It is yellowish/grayish with a small sharp bill.  It has faint streaks on its underparts, a broken white eyering, a line through its eye, and yellow under tail coverts.  It is named for its least conspicuous field mark, the orange crown which is rarely seen.  Females and juveniles are grayer than the more yellowish males.  The yellow under tail coverts are an important field mark.  That helps distinguish it from the very similar Tennessee Warbler which has white under tail coverts.  

There are four populations of this species normally separated geographically.  They vary slightly in plumage and behaviour.  It is common in the west but uncommon in the east.  

This species eats invertebrates, berries, nectar and sap, sometimes feeding from sapsucker wells.  It nests on the ground or in a low-lying shrub, preferring marshes, forest edges or swamps as nesting areas.  Its nest is made of grass and plant fibres and is lined with fur and feathers.  It lays 3 to 6 white eggs with red or brown blotches.  

An interesting fact about the Orange-crowned Warbler is that it is one of the latest fall migrating warblers and usually does not leave its Canadian breeding grounds until late September or October.  That is a fact we birders can celebrate.  It is always a good day when we see an Orange-crowned Warbler!