First Confirmed Record of Pine Warbler for British Columbia

© Rick Toochin

Citation:  Toochin, Rick. 2006. First confirmed record of Pine Warbler for British Columbia. Bird Information Web Site: www.birdinfo.com/PineWarbler.html Version 2007 01 24.

INTRODUCTION

Pine Warbler (Dendroica pinus) is a species that favours the pine-forested habitats found throughout southeastern North America. In Volume 4 of the Birds of British Columbia by Campbell et al, Pine Warbler does not appear anywhere in the text (Campbell et al, 2001). Recently there have been two reports of this species in British Columbia. The first is a sight record of a probable immature female observed at Rocky Point Bird Observatory on September 26 and 29, 1999 (Rocky Point Bird Observatory Data) and recently an immature male was photographed in Lillooet coming to a suet feeder on November 29 and December 2, 2005 (I. Routley pers. comm.). Having been photographed, the second report constitutes the first confirmed record of this species for British Columbia. The similarity of Pine Warbler to fall plumaged Blackpoll Warbler (Dendroica striata) and Bay-breasted Warbler (Dendroica castanea) makes it possible that unaware observers could miss this species without carefully considering the subtle differences between the three species. Since Pine Warbler (like all eastern warblers) has a history of vagrancy in western North America it is likely this species will occur again in BC 

DISTRIBUTION

A non-migratory population of Pine Warblers are found as residents in woodlands from eastern Texas, Arkansas, and Louisiana to North Carolina down to the Gulf Coast and throughout Florida (Dunn et al, 1997). This non-migratory population extends to the north along the coast from Virginia through Delaware (Dunn et al, 1997). A second population of Pine Warblers found in the east breed in the region but migrate south for the winter. This population is found from eastern Kentucky, Tennessee through southern regions of Illinois, southern Indiana, and southeastern Ohio (Dunn et al, 1997). Where habitat remains Pine Warblers are a localized breeder in southeast Manitoba, eastern Saskatchewan, Minnesota, Wisconsin, Michigan and across southern Ontario through southern Quebec (Dunn et al, 1997). On the Atlantic Coast this species is found in Pine Forests in the New England States and locally in New Brunswick (Dunn et al, 1997). Pine Warblers are a short distance migrant but show up out of range mostly in the fall in the Maritime Provinces usually being seen at feeders (Dunn et al, 1997). Across the rest of North America Pine Warbler is mostly a late fall vagrant occurring most frequently from October to November often in Pine habitats (Dunn et al, 1997). 

IDENTIFICATION

Pine Warbler, Blackpoll Warbler and Bay-breasted Warblers all look similar to each other in the fall. Together they make what is called collectively the “Pine-Baypoll Warbler Complex” (Hough, 1996). Adults in breeding plumage are fairly obvious and identification is straightforward. This is not the case with immature and fall plumaged birds. By carefully observing fall plumaged birds and using multiple field marks and not relying any single point, it is possible to make a positive identification. Birds showing clear markings and no variation are not a problem when a good look is obtained. The problems can occur when birds show markings found on similar looking species and have markings that overlap one another. The following section will try to explain the best features identify each species with the focus being on diagnostic or specific markings for identifying Pine Warbler.

The identification of adult male and female Pine Warblers is fairly straightforward and is shown in standard field guides. Pine Warbler is a large warbler similar in overall size to Yellow-rumped Warbler. Pine Warblers are heavy billed and long tailed making them look large in their proportions (Dunn et al, 1997).  Male Pine Warblers are identified by their brilliant yellow breast with dark streaks that start from the malar patch and continue down the sides to the rear flanks (Dunn et al, 1997). The crown, neck and back are olive green lacking any black streaking  (Dunn et al, 1997). The dark auricular patch is distinctive in this species and defines the bright yellow throat (Dunn et al, 1997).  Pine Warbler has dark eyes and bill with a yellow-whitish eye ring. There are two bold white wing bars with light edges to the tertial feather tips. The lower belly and vent are white as is the underside of the tail (Dunn et al, 1997).  The legs are black. Adult females are similar looking (but less bright yellow) to the males but lack the heavy dark side and flank streaks (Dunn et al, 1997).   Immature plumages are similar to fall plumages of Blackpoll Warblers and Bay-breasted Warblers. Care and attention to subtle details and behaviour are good clues in separating these three species. Immature male Pine Warblers are generally yellow on the breast with varying amounts of olive streaks down the flanks (Dunn et al, 1997).   The head and face are olive-green giving the species a strongly demarcated olive ear patch  (Dunn et al, 1997). The eye-ring is yellow to white in color. The large bill is black tipped with a pale base to the lower mandible. The eye is dark in color. An important feature to look for is the back color. On Pine Warbler the upper back is olive-green with no black streaks and looks solid in color  (Kaufman, 1990).  The wings are always a dull olive color and have two dull wing bars and lack white tips to the primaries (Kaufman, 1990). The primary extension is short giving the tail a long look (Hough, 1996). The lower belly and under tail coverts are white  (Kaufman, 1990).  The under tail has a large amount of white (Hough, 1996). Pine Warblers like to flick their tails as the move about allowing an observer to see bold white in the tail feathers (Dunn et al, 1997). The legs are dark in color. Immature females are very different looking to the males. They are overall a dull brownish-yellow color. The yellow is variable and is limited to the throat and the upper chest. The eye ring is broken and is white  (Dunn et al, 1997).  The bill is black tipped with a pale base to the lower mandible. There are two weak white wing bars. The under tail coverts are white as is the underside of the tail  (Dunn et al, 1997).  Pine Warblers are not exclusively found in Pine woodlands but they have preference for this type of habitat (Dunn et al, 1997). Pine Warblers feed for the most part in the upper canopy of Pine Trees but will come down and feed near the tree base or even on the ground (Dunn et al, 1997). Can be seen at all heights during migration. The tail flicking is constant and noticeable in this species (Dunn et al, 1997). Another good behavioural mark is the rather slow and sluggish manner which this species probes along the branches or ground while looking for food (Dunn et al, 1997). It is almost Vireo like in this aspect of behaviour and not acting like the other warblers by having quick flighty movements from branch to branch.

As with a few eastern warblers Pine Warbler is known to come to suet feeders in the winter months. This behaviour is not seen in Blackpoll Warbler.

 SIMILAR SPECIES.

On fall plumaged Blackpoll Warblers look for a small bill and short tail with a long primary extension (Dunn et al, 1997). In plumage characteristics Blackpoll Warblers are variable but the following clues should help observers. On the head Blackpoll Warblers have a dark line through the eye, a dark olive-green head with dark crown streaks, the upper back is also olive-green but with dark black streaks. On Blackpoll Warblers there is no strongly defined olive- green auricular patch so what is seen is weakly defined (Dunn et al, 1997). The throat is yellow to yellow-green which extends down the flanks (Dunn et al, 1997). There are dark streaks on the yellow-green sides and flanks that is a critical field mark to note in the field.  The white of the belly starts on Blackpoll Warbler from the lower chest and extends to the under tail coverts. On Pine Warbler the yellow on the breast extends lower down the chest towards the belly. The tail of Blackpoll Warbler has less white in the feathers. The legs can vary from being all fleshy colored to dark legged but on immature birds the feet are always fleshy yellow (almost never pink)(Dunn et al, 1997). 

On immature Bay-breasted Warblers look for a plainer face lacking a distinct eye ring and dark auricular patch of Pine Warblers (Dunn, 1997). Bay-breasted Warblers have black streaks on the back like immature Blackpoll Warblers but they are fainter and broken into chains while Blackpoll Warblers have long continuous back streaks (Kaufman, 1990). Another important difference found on immature Bay-breasted Warblers is the breast; side flanks and vent are dull-buffy yellow color with no streaking (Dunn, 1996).  The belly and ventral areas of both Pine and Blackpoll Warblers is white (Dunn, 1997). Like the Pine Warbler, the primaries of immature Bay-breasted Warblers lack white edges like those found on Blackpoll Warblers (Dunn, 1997). Another important mark to look for is immature Bay-breasted Warblers have dark legs and feet (Dunn, 1997).

Caution is always important when trying to identify difficult fall plumaged warblers. The best way to ensure a positive identification is to secure good pictures of any possible Pine Warbler reported in BC.

OCCURRENCE

The timing of both BC records of Pine Warbler was in the fall when vagrant birds are most likely to turn up. In both cases each Pine Warbler was found feeding and using Pine Woodland habitat. The Rocky Point bird was feeding with a large flock of Myrtle raced Yellow-rumped Warblers (Dendroica coronata coronata)(Rocky Point Bird Observatory Data). The Lillooet bird was solitary and coming to a suet feeder (I. Routley pers. comm.). Although there are only two fall records for BC it appears that observers should pay close attention to any odd looking fall plumaged Blackpoll Warbler as this species could easily go unnoticed by an unsuspecting observer.

Along the West Coast of North America Pine Warbler is a rare vagrant. There is no record for the State of Washington (Checklist for Washington State, 2005). The only accepted record for Oregon is an immature found on October 23, 1986 in the town of Harbour in Curry County  (Oregon Rare Birds Committee, 2005). In California there are 68 accepted records according to the California Rare Birds Committee with the majority of sightings coming from the months of September through till December (Rare Birds of California, 2005).

Keen observers should investigate any late "Blackpoll or Bay-breasted Warbler" sightings seen in the middle of November into the winter months.  It is highly likely that any late bird believed to be a "Blackpoll or Bay-breasted Warbler" will turn out to be a Pine Warbler since both Blackpoll and Bay-breasted Warblers winter in South America.  Another good clue indicating a Pine is if a the reported bird in the winter months is coming to a suet feeder.  With more people watching birds and our knowledge of bird movements ever increasing it seems likely that Pine Warbler will occur in BC again in the future.