16-B-2018 Blackpoll Warbler

STATUS
Pending
HOW MANY OBSERVED?
1
DATE SIGHTING OCCURRED
DATE REPORT PREPARED
REPORTER
Hilary Turner
OTHER OBSERVERS
Jeremy Welch
LOCALITY OF OBSERVATION
Market Lake Wildlife Management Area - Lone Russian Olive at: 43.771620, -112.145417
HABITAT WHERE THE BIRD WAS OBSERVED
The bird was first detected in a lone Russian Olive on the dike. It was actively gleaning insects from the foliage
SIGHTING DURATION, CONDITIONS, and EQUIPMENT USED
It was a gorgeous, sunny, windless morning at Market Lake Wildlife Management Area and it was approximately 0815 and in the mid to upper 50's. We were waterfowling and enjoying the marsh birds, but I've always eyed that lone Russian Olive, thinking it would be a good warbler tree on the right morning.

The bird was observed by two individuals at a distance of about 20 meters. One person observed with Nikon Monarch 8x42 and the other with Steiner 10x42. I first sighted a black and white warbler (note: not a Black-and-white Warbler) in the Russian Olive and said out loud, "a warbler is in the tree." Jeremy got on the bird and started giving field markings as I quickly got out of the car and tried to find it again. My first impression (by my extremely brief first glimpse) was of a black and white warbler with no yellow on it, actively gleaning insects. I knew right away that it was not a yellow-rumped because I didn't see any yellow on the bird. Jeremy first said, "It's got a black cap. Big white cheek. Two white wing bars." I got on the bird and shouted out, "It's a blackpoll!" The bird was black-capped and had a large obvious white cheek. Some faint streaking was present on the sides. It had two white wing bars.

We are familiar with Blackpoll Warblers. They are not uncommon in Montana (where we are from) during migration and I have seen many individuals, during spring migration in that state. In fact, I was surprised to have the flag on the eBird checklist. I didn't even think to take a photo, as I am used to seeing them during migration and was not aware that they were a review species in Idaho. I regret not taking a photo, but hope that my description will suffice.

Black-throated Gray Warblers would be the more expected species in this area, but I specifically looked for the yellow marking on the face for the species and it was NOT present. The body shape of the two species is not similar and their markings are only superficially similar. I am very well acquainted with both species, as well as Black-and-white Warbler. This was 100% a Blackpoll Warbler.
DID YOU TAKE NOTES?
Yes, during the observation
Yes, later the same day
DID YOU CONSULT A FIELD GUIDE OR OTHER REFERENCE WORK?
Yes, during the observation
Yes, later the same day
WHICH GUIDE(S) OR REFERENCE(S): DID YOU CONSULT?
Cornell's Merlin App was used by Jeremy in the field to confirm the identification (Note: we did not use the "Start Bird ID" feature of the app, but rather, searched for the Blackpoll Warbler after I had identified it with my own knowledge). We viewed Merlin's photos of the Blackpoll Warbler and moved on after confirming the identification. Sibley Guide to Birds was used while I was writing the report to confirm that the Blackpoll Warbler is the only North American warbler with a black cap and large white cheek patch. I did not know that the Blackpoll was a review species in the state so I wanted to check myself one more time!
DESCRIPTION OF THE BIRD(s)
The bird is in the family Parulidae. It is a warbler. Warblers are typically insectivores that glean foliage for insects. They are small passerines, typically having some yellow in the plumage and small, thin bills. This bird was a small passerine, with a small, thin bill, gleaning foliage, but possessed no yellow feathers in the plumage. We saw that the cap of the bird was completely solid black, eliminating Black-and-white Warbler. The face and lore of the bird were also completely black, eliminating Black-throated Gray Warbler. The cheek was bright white and very obvious, contrasting with the solid black cap. The bird also had two white wing bars and very fine streaking on the sides. No yellow was present on the throat, sides, or rump of the bird to eliminate yellow-rumped .
BEHAVIOR OF THE BIRD(s)
The bird was actively fluttering through the leaves of the Russian Olive, gleaning for insects. It would perch for a second or two and then flit to a new spot. It was very active, acting in a similar manner to other migrant warblers I have observed. It was not creeping, nuthatchlike, on the trunk and limbs as a Black-and-white Warbler would be seen doing. It was gleaning foliage for insects. When we left, the bird was still gleaning in the same tree. It did not fly away. Could possibly be refound. It was not near any other birds and it did not vocalize.
HOW AND WHEN DID YOU POSITIVELY IDENTIFY THE BIRD, AND WHAT CLINCHED THE IDENTIFICATION FOR YOU?
I positively identified the bird as soon as I refound it. I initially got a brief glimpse, but was on the wrong side of the car so I took binos off the bird and got out of the car quickly. It took me 10 seconds or so to relocate the bird, although Jeremy got on the bird as soon as I called it out. The critical field marking was a solid black cap and bright white contrasting cheek. As soon as I saw this marking, I knew it was a Blackpoll Warbler. Jeremy used the Merlin App (again, we did NOT use the app's Start Bird ID, where you type in field markings etc and the app pops out guesses, rather, we searched for Blackpoll Warbler) to check my ID in the field and we both examined Sibley's Guide to Birds at home, after we got the email about the Rare Bird Report.
HOW DID YOU ELIMINATE SIMILAR SPECIES? WHAT WERE THEY?
Black-and-white Warbler: eliminated because the bird did not have a white central stripe down it's crown. The bill shape and habits of the BAWW are very unique and I am familiar with this species. Our bird was not creeping, nuthatchlike, over trunks and limbs. Our bird had a solid black cap, bright white cheek, and was gleaning insects from foliage.

Black-throated Gray Warbler: eliminated due to no yellow dot in lore and no white supercilium. The black throat and strong dark streaks on the side of the Black-throated Gray Warbler also eliminate this species. I am also very familiar with this species, as it breeds in the Juniper foothills outside of Idaho Falls. Our bird had a solid black cap, bright white cheek, and very thin, faint streaking on the sides.
WHAT IS YOUR EXPERIENCE WITH THIS (AND SIMILAR) SPECIES?
I have observed Blackpoll Warblers in Montana, during spring migration. In May of 2002, Helena MT (my hometown) had an extreme weather event and Blackpoll Warblers and Tennessee Warbler poured out of the skies in a Warbler Fallout. This was my first experience with them and they were actually one of the first birds that I ever identified by myself; I was 14 years old. I have seen them on numerous other occasions during spring migration in Montana. The most recent time I saw one was in Cut Bank (up on the central Montana hi-line, near Canada) during spring migration. Jeremy was with me when we observed this bird. This Market Lake bird was the first Blackpoll Warbler I have seen in Idaho.

I have seen Black-and-white Warblers on two occasions. Once in Cut Bank, MT (a migrant trap which compares to Market Lake and Camas NWR) and once in Texas. Both times, the bird was creeping, nuthatchlike, over trunks and branches, rather than gleaning foliage. I have observed the Black-throated Gray Warbler numerous times throughout the Western US from Arizona to Idaho. We are lucky to have a small breeding population of them outside of Idaho Falls in the juniper foothills. I became very familiar with this species last summer, while birding in the juniper.
DESCRIBE YOUR GENERAL BIRDING EXPERIENCE
I am an avid birder and have been at the hobby for 20+ years. I am 30 years old, so that means I have been birding since childhood. I would rate my level of expertise as advanced to expert. I also have a BS in Wildlife Biology. I am newish to Idaho (moved to IF in Feb of 2017), but I have birded the area pretty intensely over the last year, especially Jefferson County. I have birded some with Steve Butterworth and Kit Struthers, when I have run into them in the field.
ADDITIONAL INFORMATION (If any)
Apologies, again, for not obtaining a photo. I hope that my substantive comments will suffice for this report.
WERE PHOTO(S), VIDEO, AND/OR AUDIO OBTAINED FROM THIS SIGHTING?
None