Status and Occurrence of Prairie Warbler (Setophaga discolor) in British Columbia.
by Rick Toochin
Read the full article with photos/figures here.
Introduction and Distribution
The Prairie Warbler (Setophaga discolor) is an eastern species found breeding from a few areas in Southern Ontario to eastern Oklahoma and across the south eastern United States to Northern Florida (Dunn and Garrett 1997). This species only commonly winters in Florida in North America (Dunn and Garrett 1997). In British Columbia, there are 7 Provincial records (Toochin et al. 2013). Of these records 2 have occurred in the later part of spring and 5 records have occurred in the fall (Toochin et al. 2013). Prairie Warblers, like other eastern warblers, occur as vagrants on the west coast of North America and have increased in frequency over the past few decades. In the western United States, the Prairie Warbler has been recorded in California with more than 350 records (to 2007) where it is no longer a review species for the State (Hamilton et al. 2007). Records decrease the further north travelled in the west but Oregon still has 14 accepted records as of 2012 (OFO 2012) with their being 1 record for Washington on December 29, 1989 from Walla Walla (Wahl et al. 2005, WBRC 2012) and there are 2 records for southern coastal Alaska which are both from the month of September (West 2008). The dates are September 22, 1988 on Middleton Island in the Gulf of Alaska (Tobish and Isleib 1989) and September 29, 1990 at Ketchikan in the southwestern panhandle of the State (Tobish and Isleib 1990). Future records in British Columbia are very likely as observer coverage increases and our understanding of vagrancy increases. Due to the wandering nature of the Prairie Warbler, it is a species of warbler that can occur anywhere in British Columbia.
Occurrence and Documentation
The occurrence of Prairie Warbler in British Columbia has slowly increased as knowledge of eastern warbler vagrancy has increased amongst the Province’s observers. Of the 7 Provincial records, 2 are photo documented with the rest being documented with well written field notes. Records in September reflect the fall migration peak movement of this species. The November and December records likely reflect lost migrant birds or birds pushed north by late fall storms like the “Pineapple Express” that pushes storms up from waters off Hawaii and off California northward towards coastal Vancouver Island and the Queen Charlotte Islands. It is possible that birds ending up in this region in November and later come from lost birds at sea off California and are pushed northward by these fast tracking storm fronts. This purely speculation at this time but as records of more and more eastern vagrants occur at this time in the fall in this region after or during this weather event someday the evidence might become more solid. This species should be looked for in the late May early June overshoot window that is reflected with 2 Provincial records to date. Prairie Warblers on migration will use open habitats such as young deciduous trees such as Birch, Willow or Alder Trees to feed but do also prefer open scrubby habitats to feed. The bird in Sooke was found in a mixture of Scotch Broom and open hedgerow habitat while the bird in Tofino was in hanging out in a small grove of Alder and Birch Trees (Toochin 2012). In the breeding season Prairie Warblers prefer scrubby successional habitat such as regenerating fields, pastures, clear-cuts, power line right-of-ways, old abandoned orchards or small patches of habitat. Prairie Warblers are found in the winter in open scrubby clearings and edges. All the British Columbia records are listed below in Table 1.
Table 1: Prairie Warbler Records for British Columbia:
1.(1) adult male June 17, 1977: Doug Brown: Mount Kobau (Cannings et al. 1987, Toochin et al. 2013)
2.(1) male December 18, 1993-January 25, 1994: Peter Hamel, Margo Hearne: Masset, Queen Charlotte Islands (Toochin et al. 2013)
3.(1) adult male singing May 29, 1995: Aurora Patterson: Chesterman’s Beach near Tofino (Toochin et al. 2013)
4.(1) immature male September 8, 1995: Mitch Meredith, and other observers (photo/banded) Triangle Island (Campbell et al. 2001, Toochin et al. 2013)
5.(1) immature November 16-19, 2008: Jan Bradshaw, and other observers (photo) near Tranquille just west of Kamloops (Toochin et al. 2013)
6.(1) immature November 23, 2008 & December 28, 2008: Rick Toochin: Sooke (Toochin 2012)
7.(1) immature male September 28 – October 3, 2009: Adrian Dorst, and other observers (photo) Tofino (Charleswort 2010)
Read the full article with photos/figures here.
