Townsend’s Warbler Dendroica townsendi
Cascade Creek (near Ano Nuevo State Reserve), California. January 2007

On the 11th of January 2007 I had the most memorable two hours birding I’ve had for a long time watching wintering warblers feeding at very close range over a thick pile of rotting sprouts in a field at Cascade Creek close to the Ano Nuevo State Reserve (near Pescadero and just off Highway 1).

The smell coming from this pile of liquifying veg was - well, ‘interesting’, (and also clinging and penetrating, especially when I mistook what turned out to be a thin dry crust for solid ground and sank up to my ankles into a viscous brown gloop) but getting what surely has to be uniquely close views of tens of Townsend’s and Yellow-rumped Warblers (and a very obliging 1st winter female Hooded Warbler) dipping their bills into a soup of festering vegetables just a few feet away more than compensated for the stink coming up from my trainers (though Jack Cole, San Jose resident and long-suffering friend who I went to Ana Nuevo with, did apparently take rather a long time to hose the ‘delicate aroma’ out of his car after I’d gone back to the UK - sorry about that!).

Note in some of the photos the now-dried “liquid sprout” - like dried molasses almost - around the bill and on the forehead picked up when foraging.

 

 

 

Adult Males:

 

 

 

 

 

 

 

Adult Females (?):

 

 

 

 

1st winter Females:

 

Townsend’s Warblers breed in mature coniferous and mixed forests from east-central, south-central, and southern Alaska south through much of British Columbia to the Olympic Peninsula in Washington, and to the mountains of western Montana, the Idaho panhandle, and northeast Oregon.

Townsend’s Warblers have two separate winter ranges. Those that breed on the Queen Charlotte Islands winter on the Pacific coast from British Columbia to southern California. Other Townsend’s Warblers migrate to southeast Arizona and southwest Texas, extensive stretches of montane habitat in Mexico, and parts of Guatemala, Nicaragua, Honduras, and Costa Rica. Those individuals that winter on the Pacific coast have shorter wings than those wintering in Arizona, Texas, Mexico and Central America, raising the possibility that the two groups should be considered distinct subspecies.

Townsend’s and Hermit Warblers D. occidentalis are very closely related; they often hybridize in the narrow zones where their ranges overlap. Researchers believe that Townsend’s Warblers are displacing Hermit Warblers in these zones, in part because male Townsend’s Warblers show greater aggression, maintain their territories more effectively, and attract females more readily than Hermit Warblers. Townsend’s Warblers also lay more eggs per clutch than Hermit Warblers in the hybrid zone; this difference may be another selective advantage for Townsend’s.
(Adapted from http://www.birds.cornell.edu/BOW/towwar/)

All photos copyright Charlie Moores