- 5.5 in
- 7.9 in
- 0.3–0.5 oz
- Paruline à tête jaune (French)
- Chipe cabeza amarilla (Spanish)
- The Hermit Warbler hybridizes with the Townsend's Warbler where their ranges overlap in Oregon and Washington. The hybrid zones are rather narrow and appear to be slowly moving, with the more aggressive Townsend's Warbler displacing the Hermit Warbler.
- Hermit Warbler females have been found to prefer to mate with Townsend's Warbler-type males, but no evidence was found of Townsend's Warbler females mating with Hermit Warbler males.
- The oldest recorded Hermit Warbler was a female, and at least 9 years, 1 month old when she was recaptured and rereleased in California in 2006.
Tall coniferous forests, especially of Douglas-fir.
Insects and spiders.
- Clutch Size
- 4–5 eggs
- Egg Description
- Creamy white with fine dark speckles around large end.
- Condition at Hatching
- Helpless with tufts of down.
Open cup of fine twigs, rootlets, dry moss, bark, pine needles, and spider silk. Lined with fine plant fibers and hair. Placed on top of conifer branches, well concealed from above.
Gleans insects of middle and outer portion of tree branches. Often hovers.
Hermit Warbler populations were stable between 1966 and 2015, according to the North American Breeding Bird Survey. Partners in Flight estimates a global breeding population of 2.5 million, with 100% breeding and migrating through the U.S., and 82% wintering in Mexico. The species rates an 11 out of 20 on the Continental Concern Score. Hermit Warbler is not on the 2016 State of North America's Birds' Watch List. It is a U.S.-Canada Stewardship species. Because of its specialized habitat and its small range, Hermit Warbler may be vulnerable to habitat alteration. Townsend's Warbler may be displacing the species in parts of its range.
- Pearson, S. F. 1997. Hermit Warbler (Dendroica occidentalis). In The Birds of North America, No. 303 (A. Poole and F. Gill, eds.). The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union, Washington, D.C.
- North American Bird Conservation Initiative. 2016. The State of North
America’s Birds 2016. Environment and Climate Change Canada: Ottawa, Ontario.
- Partners in Flight. 2012. Species assessment database.
- Pearson, S. F. 2000. Behavioral asymmetries in a moving hybrid zone. Behavioral Ecology 11: 84-92.
- Rohwer, S. and C. Wood. 1998. Three hybrid zones between Hermit and Townsend's warblers in Washington and Oregon. Auk 115: 284-310.
- USGS Patuxent Wildlife Research Center. 2016. Longevity records of North American Birds.
- USGS Patuxent Wildlife Research Center. 2015. North American Breeding Bird Survey 1966–2015 Analysis.