Status and Occurrence of the Hermit Warbler (Setophaga occidentalis) in British Columbia(July 2013)
by Rick Toochin
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Introduction and Distribution
The Hermit Warbler (Setophaga occidentalis) is a secretive species of warbler that breeds in coniferous forests, from western Washington State (the Olympic Peninsula, east of the Olympic Mountains, rarely at the southern end of Puget Sound), south through the Cascades into western Oregon, south through the Sierra Nevada Mountains of California, and in the coast ranges of Marin County (Curson et al. 1994, Dunn and Garrett 1997, Wahl et al. 2005). There is a small population of breeding birds in the Santa Cruz Mountains as well as the San Gabriel and San Bernardino Mountains of Southern California (Dunn and Garrett 1997). The Hermit Warbler winters primarily in the montane forests of western Mexico from Sinaloa, Durango and southern Nuevo Leon, south through the highlands of northern Central America to Nicaragua (Curson et al. 1994, Dunn and Garrett 1997). The Hermit Warbler regularly winters in coastal California from north of San Francisco to San Diego, and is recorded occasionally further north as far as Washington State, and as far inland as central California (Dunn and Garrett 1997, Sibley 2000, Wahl et al. 2005, Dunn and Alderfer 2011). In migration the Hermit Warbler is recorded in southern Nevada, with most birds passing through Arizona, and some birds passing through New Mexico and West Texas (Dunn and Garrett 1997, Sibley 2000, Wahl et al. 2005, Dunn and Alderfer 2011). As a vagrant, the Hermit Warbler has been recorded throughout the eastern United States and Canada (Godfrey 1986, Dunn and Garrett 1997, Dunn and Alderfer 2011). The Hermit Warbler is an accidental vagrant to south east Alaska (West 2008).
In British Columbia this species occurs as a casual vagrant. There have been 30 records of the Hermit Warbler recorded with all records coming from coastal areas of the Province (Campbell et al. 2001, Toochin et al. 2013).
It is important to note that just south of British Columbia, the Hermit Warbler freely hybridize with the closely related Townsend’s Warbler (Setophaga townsendi) in northern Washington in the Olympic Mountains, as well as in the Cascade Mountains around Mount Rainier and Mount Adams (Dunn and Garrett 1997, Eckert 2001). This hybridization zone also runs south along the western slope of the Cascades into northern Oregon (Dunn and Garrett 1997, Eckert 2001). The common occurrence of hybrid birds in these regions makes identification of Hermit Warblers out of range in British Columbia problematic and difficult. Observers need to get both upper views and underside views of birds to try and rule out hybrid birds. Some birds are impossible to identify without having them in the hand (Dunn and Garrett 1997, Eckert 2001). The Hermit Warbler is a species that should be looked for in British Columbia in the future by keen observers.
Occurrence and Documentation
Records of the Hermit Warbler in British Columbia reflect the known peak migration period for this species. In Arizona and California, peak migration period is from April 25 to May 10, with smaller numbers of birds moving north in the latter half of May into early June (Dunn and Garrett 1997). Over half of the records found in British Columbia come from the April 25 to May 10 time period, and are mostly overshoots of adult males heading north (Dunn and Garrett 1997, Campbell et al. 2001, Toochin et al. 2013, Please see Table 1). The number of records decreases as May progresses with a few June records; there is a scattering of summer records and few fall records (Toochin et al. 2013). The Hermit Warbler is like the Townsend’s Warbler in that both species like to live in the tops of tall coniferous trees making them difficult to see (Dunn and Garrett 1997, Dunn and Alderfer 2011). Another problem for observers is that the vocalizations of Hermit Warbler completely overlap those given by the more common Townsend’s Warbler (Dunn and Garrett 1997, Eckert 2001). The Hermit Warbler has been found paired off with Townsend’s Warbler at Toad Lake, near Pt. Alberni on Vancouver Island (Innes 1995). Also, a pair of Hermit Warblers responded to tape play-back at Sooke Mountain Provincial Park in Sooke (Toochin et al. 2013, Toochin 2012b, please see Table 1). It should be noted that for three summers after this sighting, a hybrid Hermit Warbler and Townsend’s Warbler was photographed and seen on territory in the park (L. Haviland Pers. Comm.). Hybrid Hermit Warblers have been recorded multiple times along the coast of British Columbia from Vancouver, Victoria, Duncan, Campbell River, Gold River, Port Alberni, Tofino, Chilliwack and as far east as Manning Park (Campbell et al. 2001). With any observation of a suspected Hermit Warbler, observers must see both the underside and upper side of the bird to rule out potential hybrid birds (Campbell et al. 2001, Eckert 2001). Of the 30 records only a handful are photographed, but given the recent explosion of digital cameras used by birders, it is likely that future records will be photographed (Toochin et al. 2013, Please see Table 1). The Hermit Warbler is often found in mixed flocks of Black-throated Gray Warblers and Townsend’s Warblers and in known warbler migrant traps along the coast of British Columbia. Any odd sounding “Townsend’s Warbler” should be tracked down by observers and checked with a visual identification because Hermit Warbler vocalizations overlap extensively with Townsend’s Warbler (Campbell et al. 2001, Eckert 2001). With more observer coverage, it is almost certain there will be more Hermit Warblers found British Columbia in the future.
Table 1: British Columbia records of Hermit Warbler
1.(1) adult male May 15, 1946: George Hardy: Lost Lake, Saanich, near Victoria (Hardy 1947, Toochin and Fenneman 2008)
2.(1) adult breeding plumage singing male June 12, 1971: Roger Taylor Thetis Lake Park, outside Victoria (R. Taylor Pers. Comm.) (Toochin and Fenneman 2008)
3.(1) adult male plumage May 8, 1982: Ian Kinman: Chancellor Boulevard, Vancouver (Weber 1985, Toochin 2012a)
4.(1) adult breeding plumage singing male May 2, 1990: Mike Chutter: west of Nanaimo (Campbell 1990c, Toochin and Fenneman 2008)
5.(1) adult breeding plumage female May 8, 1991: Rick Toochin: Klanawa River, just outside PRNP (Campbell 1991b, Toochin and Fenneman 2008)
6.(1) adult breeding plumage singing male April 25, 1992: Mark Wynja, mobs (photo) Queen Elizabeth Park, Vancouver (Bowling 1992c, Dorsey 1996b, Toochin 2012a)
7.(1) adult breeding plumage singing male April 28-29, 1992: Bryan Gates, mobs: Mt. Douglas Park, Victoria (Bowling 1992c, Davidson 1993, Campbell et al. 2001, Toochin and Fenneman 2008)
8.(1) adult breeding plumage singing male April 29, 1994: L. Grover: Reifel Migratory Bird Sanctuary, Ladner (Toochin 2012a)
9.(1) adult breeding plumage male May 18-June 20, 1994: Doug Innes, mobs: Toad Lake, near Pt. Alberni (Siddle 1994b, Innes 1995, Toochin and Fenneman 2008)
10.(1) ad breeding plumage female May 30, 1994: Derrick Marven, mobs: Toad Lake, near Pt. Alberni (w/male hybrid) (Siddle 1994b, Toochin and Fenneman 2008)
11.(1) adult breeding plumage female May 6, 1999: Mike Toochin: Queen Elizabeth Park, Vancouver (Bowling 1999c, Toochin 2012a)
12.(1) adult breeding plumage singing male May 6, 1999: Rick Toochin, GB: Queen Elizabeth Park, Vancouver (Toochin 2012a)
13.(1) adult breeding plumage singing male May 2, 2000: Nathan Hentze: Courtenay (N. Hentze pers. Comm.) (Toochin and Fenneman 2008)
14.(1) adult breeding plumage singing male May 11, 2001: Dan Petersen: Burnaby Mountain Park, Burnaby (Bain 2003c, Toochin 2012a)
15.(1) adult breeding plumage singing male May 18, 2001: Rick Toochin: Derby Reach Regional Park, North Langley (Cecile 2001c, Toochin 2012a)
16.(1) adult male June 30, 2002: Sandy McRuer, mobs: Two River Arm, Sproat Lake (Yahoo message #2011 BCBIRDINGVANISLAND, Toochin and Fenneman 2008)
17.(1) adult breeding plumage singing male May 14, 2003: Dan Petersen: Burnaby Mountain Park, Burnaby (Cecile 2003c, Toochin 2012a)
18.(1) adult breeding plumage singing male May 9, 2004: fide John Kalman: Bridal Veil Falls, Chilliwack (Toochin 2012c)
19.(1) adult breeding plumage male May 21, 2006: Bryan Gates, and other observers: Mount Tolmie, Victoria (Cecile 2006c, Toochin and Fenneman 2008)
20.(1) adult breeding plumage male April 21, 2007: Rick Toochin: Jordan River (Cecile 2007c, Toochin 2012b)
21.(1) adult male breeding plumage May 1, 2007: Chris Saunders: Observatory Hill, Victoria (Yahoo message #12182 BCVIBIRDS, Toochin and Fenneman 2008)
22.(2) adult male and female May 12, 2007: Rick Toochin, Corina Isaac: Sooke Mountain Park (Cecile 2007c, Toochin 2012b)
(1) adult male May 13, 2007: Rick Toochin, Louis Haviland: Sooke Mountain Park (Cecile 2007c, Toochin 2012b)
23.(1) adult breeding plumage female May 16, 2008: Chris Turner: Lighthouse Park, West Vancouver (Toochin 2012a)
24.(1) adult breeding plumage male May 25, 2009: John Vroegop: along Carolin Mine Road, Sowugia River off Coquihalla Highway (Toochin 2012c)
25.(1) fall plumage August 6, 2009: Ruth Herman Kerryview Drive, near Prospect Lake, Victoria (Yahoo message #11398 BCVIBIRDS)
26.(1) male September 8, 2009: mobs: Lynus Lane and River Road, Richmond (Toochin 2012a)
27.(1) adult male June 3, 2010: Guy Monty: Spider Lake Provincial Park, outside Qualicum Beach (Yahoo message #14526 BCVIBIRDS)
28.(1) adult male May 29, 2011: Doug Brown: along the Stillwater Main forest road near Powell River, just past the Lois Lake dam (BC Bird Alert: Accessed June 2, 2011)
29.(1) adult breeding plumage female July 19, 2011: fide Dan Petersen: Central Park, Burnaby (Toochin 2012a)
30.(1) adult breeding plumage singing male May 5, 2013: Rick Toochin: Emory Creek Provincial Park, outside Yale
Acknowledgements
I wish to thank Jamie Fenneman for reviewing the manuscript. I also wish to thank Louis Haviland for providing me information on the sightings from Sooke Mountain Provincial Park.
