[Samantha Hauser] Welcome to today’s webinar, we’ll be discussing fall warbler identification. 

My name is Samantha, I’m with the Cornell lab and I will be facilitating today’s webinar. Today’s webinar is hosted from Ithaca, New York, where both Cornell University and the Cornell Lab of Ornithology are located. It is important to recognize the original stewards of this land, the people have a historical and continued connection to this place, and the traditional ecological knowledge held and shared from these communities. 

Please stay with me as I read a brief statement acknowledging, and made in collaboration with, the indigenous people of this area. Cornell University is located on the traditional homelands of the Gayogohó:nǫ (the Cayuga Nation) the Gayogohó:nǫ are members of the Haudenosaunee Confederacy, an alliance of six sovereign Nations with a historic and contemporary presence on this land. The Confederacy precedes the establishment of Cornell University, New York state, and the United States of America. We acknowledge the painful history of Gayogo̱hó:nǫ dispossession, and honor the ongoing connection of Gayogo̱hó:nǫ people, past and present, to these lands and waters.

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Unfortunately, our instructor Eric Ripma is unable to join us today due to an unexpected illness. Instead, our own Dr. Kevin McGowan has graciously stepped in at the last minute to serve as your expert instructor. 

Kevin is a professional ornithologist and avid birder. He is the author and instructor for many of the Bird Academy courses, including the Be a Better Birder: Warbler Identification course. 
Kevin was the co-editor and primary author for the book, The Second Atlas of Breeding Birds in New York State, one of the creators of the Cornell Lab’s All About Birds website, and the former curator of the bird and mammal collections at the Cornell University Museum of Vertebrates. 
Needless to say, you are in good hands today.

Kevin enjoys all aspects of birds (especially crows), from behavior to functional anatomy, and from ecology to evolution. He is interested in spreading the appreciation of birds to all possible audiences, through all possible avenues. 

And with that, I will pass the webinar over to Kevin McGowan!

[Kevin McGowan] So, thanks for the introduction and welcome everybody to the “Ins and Outs of Fall Warbler Identification Webinar”. I want to thank Eric Ripma for putting this presentation together. It’s a shame he can’t be here to present it, but he’s the author and I’m doing my best to present his ideas and work. He put together this set of slides and the concepts that I’m going to pass on to you today. 

Right now is a very exciting time of the year, it’s fall migration. This is an exciting time because millions of birds are heading south through the US and Canada each evening. I love it! 

So we’re going to help you ID these fall warblers tonight. As with most things biological there’s quite a bit of variation, when I show you slides you’ll see fall birds on the vibrant side of the spectrum on the left, and less vibrant birds on the right. Sometimes I’ll show you species that are particularly similar. 

You’ll see a lot tonight, don’t worry you’ll have the recording in a downloadable cheat sheet specific to fall warblers to come back to. Okay let’s get started! 

In this program we’ll be covering the Parulidae or the new world warbler family. As you can see there are 115 species worldwide, all of which only regularly occur in the new world (hence the name New World warblers). Of those 115 species, 48 commonly occur in the US and Canada. 
There are an additional seven species that occur as rare breeders vagrants that we’re not going to cover today. 

Some general characteristics to note about warblers is that they’re small, they have thin insect eating bills, short to medium length tails, thin fragile legs, and they’re active foragers. 

Warbler identification can be a challenge at any time of the year due to the great diversity within the family, but it’s especially difficult in the fall due to plumage variation. Many of the species we’ll be covering will look significantly different depending on their age and their sex. So instead of learning one plumage, you need to be aware of two or three. 

Luckily there’s some overall patterns that are usually shared between all individuals within the species, and a few things to notice when we’re looking at the Warblers include the overall color pattern, what color is the bird above and below? Does it contrast? Also pay attention to facial pattern: there are many distinctive face patterns that we’ll be going through. Does it or doesn’t it have wing bars? Or streaking? If it has streaking, where’s the streaking? And how thick is it? Even fall warblers have a lot of color, so pay attention to what and where those colors are on the bird.

To make the challenge of warbler identification more manageable we split them into 10 groups that share similar characteristics. We’ll talk about each group and discuss why they’re in the group, which characteristics place them in the group, and how to identify each species within that group. After we’ll go through each species more closely and compare similar species when necessary. At the end of each group we’re going to have a quiz.

So let’s start with the “Brown Warbler Group”. 

We start with them because they have very little plumage variation due to age or sex. You just need to learn one plumage during fall migration. These species are almost always found on the ground or in low vegetation. These are some of our chunkiest and slowest moving of the Warblers. 

They all have striped head patterns, but those vary. All of them have eyebrow stripes or what we call superciliums, except for one, which has an eyering – you can likely see which one that is from the slide. To differentiate within the group pay attention to overall color tone, eyering, supercilium, and pattern of streaking.

So we’ll start with these three brown warblers, all of which are streaked below. The Ovenbird is a mostly eastern US and Canada bird and it’s rare on the west coast. The Ovenbird is the most distinctive of the group and can be quickly differentiated from every other bird by seeing its white eyering and the rusty crown with dark borders. It’s a fairly distinctive little bird. 

The two species of waterthrushes are much more difficult to distinguish, but there are a few key features to look for. The Northern Waterthrush is widespread but more common in the East, uncommon to rare in the west. And its features are, notice that it has dense streaking below, including the throat. It also has a buffy, single colored, supercilium or eyebrow stripe, and that it has dull legs. The Louisiana Waterthrush is only found regularly in the East and is most common in the Southeast. Its key features are notice that it’s streaked below like the northern, but the streaks are farther apart. It also has a mostly white throat, and it has brightly colored legs. These three species have some behavioral clues, as well the Ovenbird, cocks its tail up while it walks on the forest floor. And the waterthrushes constantly bob their tails and rear end, that’s a really good characteristic to know you’ve got a waterthrush.

The last of our two brown warblers are relatively easy to identify. The Worm-eating Warbler is found mainly in the Southeastern U.S. As you can see on the Worm-eating warbler on the left, the black and caramel colored head stripes, including a central crown stripe, make it easy to identify this species. Swainson’s Warbler is only regularly found in the Southeastern U.S. In the Swainson’s Warbler we will be looking for more russet or buff tones, and a russet crown and buffy supercilium. 

Okay, it’s quiz time! Which one of the “Brown Warblers” are these? They’re just brown warblers, but they’re kind of handsome in their own way.

Okay I think we’ve got most of the things here, we’re going to end the poll now and see how well you did.

Alright, so quiz number one, almost everybody realized it was a waterthrush, but it was a pretty even division on which one. But just slightly more than half of all the participants decided it was a Louisiana Waterthrush, again that’s right because of the white throat and those bright colored legs. 

Number two, we had a pretty good consensus that this was a Worm-eating Warbler and about 3/4 of the people got that right, because of the uniquely colored head stripes. Okay thanks very much for participating. 

Our next warbler group is a little larger. This is the “Plain Yellow Warbler Group”. The warblers in this group all have yellow or olive backs and no dark streaking. The Yellow Warbler has rufous streaking in some plumages and the Orange-crowned has blurry olive streaking, but no dark streaking. To identify birds in this group, pay attention to the head and face patterns, the color of the undertail coverts, and wingbars. 

Blue-winged Warbler is a fairly distinctive warbler that’s found mostly throughout the Eastern U.S. The yellow body and blue wings combined with a black eyeline and white wingbars identifies the Blue-winged quickly. They can be less vibrant, but still show the same overall field marks like the bird in the middle photo. The Prothonotary Warbler is a most similar species, but it lacks the wingbars and eyeline of the Blue-winged.

A little more on the Prothonotary Warbler they’re found in the Eastern U.S. and are most common in the Southeast. Notice the bright body, the bright yellow color overall, the lack of wingbars and lack of an eyeline. They can also be much less vibrant, but still have the overall pattern. As we saw in the last slide, the Blue-winged Warbler is the most similar species, but it has wingbars and a black eyeline. 

The Kentucky Warbler is found only in the East and most commonly in the Southeastern United States. All ages and sexes are similar so you only need to remember one plumage. It’s also a distinctive warbler and is easily identified by the combination of overall color, black sideburns, and what Eric calls a yellow “candy cane” face pattern. Let’s look at that for a second. I would have called it spectacles, but look it really is in the shape of a candy cane going around the eye, so that’s memorable.

Next, we have the Wilson’s Warbler, which is a widespread species that can be found from coast to coast through much of Canada and in Alaska. It’s more common in the West, than in the East. When Wilson’s have their, what Eric calls their black toupé or black cap they’re easy to identify. Also note the overall coloration, Olive above and bright yellow below. Some young birds don’t show the black cap so we need to pay attention to the face pattern. Notice the olive cheek and thick, but not contrasting yellow supercilium. This is a bird we’ll come back to in a couple of slides. 

The Hooded Warbler is found in the East and most commonly in the Southeastern U.S.. 
Males are very distinctive just note the black hood including the throat and the yellow face. There’s nothing else like it, this is one of my favorites. Females however lack the contrasting hood, we need to pay close attention to the face pattern on these birds. Note the yellow face with the faint outline of the hood. So we’ll take a closer look at the female hooded’s in the next slide. 

When Hooded and Wilson’s Warbler lack their contrasting head patterns, they’re very similar to each other. Notice the difference in face pattern between these two birds. The Hooded on the left shows a blank face with a dark outline of a hood. If you can see the tail, you can quickly differentiate the two species, because this one has white tail stripes. Wilson’s doesn’t have any white in the tail. On the Wilson’s, note the difference in the face pattern: an olive cheek and low contrast, yellow supercilium that’s thick behind the eye. Those are the main differences.

Tennessee Warbler is found mainly in the Central and Eastern U.S. and Canada. They’re common migrants in the East, and somewhat rare but regular on the West Coast. Some birds, mostly the males, have more pearly gray coloration. Notice the olive above and pearly gray below, also note the indistinct dark eyeline and sharply pointed bill. Most fall birds are more yellow overall, but they still have the dark eyeline and indistinct wingbars. Also note the white undertail coverts. The main thing to note on a Tennessee Warbler is there aren’t any bold field marks, it’s mostly a plain bird.

Orange-crowned Warbler is common across North America, North through Canada and Alaska. It’s abundant in much of the West and uncommon in much of the East. The plumage is similar between the age and sexes but the brightness varies geographically, with being much brighter in the West. It has a mostly uniform coloration not much contrast between upper- and underparts, but it has blurry olive streaking below. Note the dark eyeline with white or yellow eye arcs, and also the yellow undertail coverts, this is an important field mark.

These are two species that are often confused. Neither have any bold field marks to quickly identify them. The main thing to note are the white undertail coverts on the Tennessee Warbler, and the dark eyeline and pale supercilium. On the Orange-crowned, notice that the undertail coverts are yellow not white, and the dark eyeline with the pale eye arcs, instead of a pale supercilium.

Our last warbler in this group is the Yellow Warbler. This is also a widespread species that can be seen coast to coast, and far North through Northern Canada and Alaska. This is a bright yellow warbler overall without much patterning. Adult males have rusty streaking below and when that’s present this is diagnostic. However most birds in the fall don’t have the rufous streaking. When there’s no streaking, pay attention to overall coloration, bright to dull yellow; a blank face with an indistinct eye ring, and yellow to white edging on the tail and feathers. And this is actually important, you can see that it’s yellow in the tail feathers. And Yellow Warbler is the only warbler that has actual yellow tail spots. Other warblers have white spots, if they have anything. 

Okay, it’s quiz time, which members of the “Plain Yellow Warbler Group” are these? Polls open, go ahead and make your selection. And if you aren’t sure just take a guess. You don’t get penalized for getting this wrong.

And I think we’re about ready to call it here.

Okay, that’s good, a lot of people participating, thank you. So let’s see what we’ve got. Yellow warbler is the answer for the first one and about two-thirds of the participants agreed on that. You can see a little yellow edging on the wing feathers, also it’s plain yellow all over, with a little tiny yellow eyering.

And Hooded Warbler is the answer to the second one and again about the same number, two-thirds people figure that one out. You can see just the hint of that hood there, and those big white tail spots showing very well in this particular photo. Okay, great, let’s move on. 

Next up is our “Gray-headed Yellow Warbler Group”. These species are found on the ground or in low levels of vegetation, except for the Nashville can be up high in the trees. They all have gray heads or hoods, except the Common Yellowthroat, and there are no wingbars in this group. To identify the members of the group pay attention to: the eyerings or eye arcs, the throat and chest coloration, and apparent tail length.

First up is a Common Yellowthroat, and this is a very common bird across much of North America. On the males, the combination of black mask bordered with white above and yellow throat, and undertail coverts quickly identify it as a Yellowthroat. On females and young, note the overall olive or tan coloration with contrasting yellow throats and undertail coverts. It also has pale eye arcs. Let’s look at that to see exactly what I mean. It means that it’s not quite an eyering, it’s broken, so they’re two half circles that we call eye arcs.

Nashville Warblers are widespread across the U.S. and southern Canada. Note the overall body coloration: the bright yellow below and olive above, the combination of a gray head, a white eyering, and a yellow throat. There are less colorful plumages but the overall patterning is pretty much the same.

The Connecticut is only regularly found in the East, during fall migration, and it’s one of the least numerous warblers. If you find one, consider yourself lucky. The main field marks to note are the gray face and chest giving a hooded appearance, and a complete or near complete eyering. The bird also appears short-tailed because of the long undertail coverts. Some females and young birds have less of a gray hood and more of a grayish, olive throat and upper chest that blends into the back. Note the bold near complete eyering.

MacGillivray’s Warbler is found commonly throughout Western U.S. and Canada, and only rarely in the East. On the adult males, notice the blue-gray hood with a dark lower border, and thick white eye arcs. You can really get a sense of what an eye arc is here with a male McGillivray’s Warbler. Most birds in the fall will be less vibrant, but note the same overall pattern with a light gray hood, instead of the dark blue gray hood.

During fall migration the Mourning Warbler is found mostly in the Eastern U.S. On adult males, notice the dark blue-gray good with darker lores in front of the eye, and no white around the eye. In the fall, most individuals will be less vibrant with paler gray hoods or less distinctive hoods altogether. These individuals have narrow, white eye arcs. Notice a yellow throat and gray chest, which is only a slight chest band on the dullest of the individuals.

In some plumages these species could be extremely similar. For Connecticut, note the near complete narrow white eyering with an olive chest and throat, and a short tailed appearance. MacGillivray’s Warbler, note the grayish hood with paler white throat and thick white eye arcs. And finally for Mourning, look for the grayish head, yellow throat, and near complete eyering. 

Not easy, but let’s see how you can do. It’s quiz time again. Which members of the “Gray-headed Yellow Warbler Group” are these? Poll’s open, take a guess.

I really like this group of birds, I think they’re beautiful. They look like they’re yellow all the way through, sometimes when they’re so bright yellow.

Okay the poll’s ending soon, So please get your answers in and we’ll see how you did. 
It appears one of these is easy and one of them is very hard. 

Alright, okay, let’s see what the first one is. First one is a Mourning Warbler, but MacGillivray’s came in second in our poll. Just over half of the people figured out that this was a Mourning, but it doesn’t have those eye arcs that a MacGillivray’s Warbler does and it has black in the throat that a Connecticut Warbler would not. Alright, how about the second one. And that’s a Common Yellowthroat and about three-quarters of the people figure that one out. A yellow throat and yellow under the tail, and a nice dull alive above. All right, very good.

The next is a small group of the “Gray Warbler Group”. All of these birds are primarily gray with splashes of red or yellow. They all have eyerings, two with very bold eyerings. To identify the birds within this group pay attention to the under- and uppertail covert coloration, and the eyerings and the body coloration.

First up is the Colima Warbler and this bird has a very limited range in Mexico, and breeds only in the Big Bend region of Texas in the United States. So in most places you don’t need to worry about this species. In fact, if you want to see this species you have to take about ten mile hike up into the Chisos mountains in Big Bend to see them when they’re breeding. It’s the only place in the U.S. they are. 

They have an overall gray coloration with a grayer head and a buffier body, which usually identifies this species. Also note the bold white eyering, and the yellow upper- and undertail coverts. Notice here you can see that it’s yellow above as well as below. They also have a red crown, depending on their age, but this could be very hard to see. Let me zoom in here to show you this on this Colima Warbler. The other gray warblers also have this red crown depending on their age and sex, but as I said it’s usually not visible, it’s kind of hard to see.

Lucy’s warbler is only regularly found in the Southwestern U.S. and Mexico, with vagrants showing up on the West Coast and one bird making it to the Upper Peninsula of Michigan. First note the overall coloration: sort of bicolored with dark gray above and buffy white below. Note the pale coloration around the eye forming an indistinct eyering, if seen the thick brick- Let me just show you. It has a brick-red rump patch which is distinctive. Young birds look similar, but their rump is not as red and they have buffy wingbars, and a more pronounced supercilium.
However, the same field marks can make the identification: gray above, whiter below, and a rufous rump.

Virginia’s Warblers are widespread in the mountains of the Southwestern U.S.. They’re gray overall, slightly paler below than above. This bird is quickly recognizable with a combination of yellow chest spot, yellow upper- and undertail coverts, and a bold white eyering. Some birds show little or no yellow on the chest, so pay attention to the same field marks, though: bold white eyering and yellow under- and uppertail coverts. When they lack yellow they look really similar to Colima Warbler, but there are few areas of overlap in range. 

Okay, quiz time! Which members of the “Gray Warbler Group” are these? Polls open, see what you can figure out. Kind of cute little birds, but not the flashiest of the warblers.

Okay the poll’s ending soon, so get your answers in and we’ll see how you did.

Okay, how’d we do?

Alright, the first bird is a Virginia’s Warbler. It’s the only one of the three that has yellow on the chest, so about two-thirds of the participants got that. Very good. And then the other is a Lucy’s Warbler showing that reddish uppertail. And again, about two-thirds of the people got that one as well. Very Good.

Alright next up is the “Streaked Yellow Warbler Group” and this is composed of warblers with plumages of yellows, browns, and grays, with dark streaking on the sides or chests. They all have wingbars, except for the Canada Warbler and they’re kind of indistinct on Prairie and Palm Warbler, but they all have wingbars except those. And we’ll want to pay attention to the pattern of yellow plumage, the quality and location of streaking, and the facial pattern.

Kirtland’s Warblers mainly breed in the lower peninsula of Michigan. During fall migration they’re rare anywhere, but most often seen in the far Eastern U.S. This is another species to consider yourself lucky if you see it away from breeding grounds. Adult males are fairly distinctive. Note the dark side and back striping, and dark lores with white eye arcs. Some females and young birds are much less distinct, they have the same overall patterning but the streaking is different. Notice the dense short streaks on a yellow background, below and across the chest. 

Kirtland’s Warbler also has a behavior tip, it is one of the birds that pumps its tail regularly. It’s not quite like the whole backend, body bob/tail bob that the waterthrushes do. It’s a more sort of leisurely pump, more like a phoebe, something like that if you’re familiar with those. Just lightly bobbing the tail, pumping it, as they’re perched

Magnolia Warbler is common migrant in the East, and a regular vagrant in the West. Magnolia Warblers have a lot of field marks. They have a gray head, greenish back, and are bright yellow below. When you combine this with the black flank streakings you can identify these as Magnolia Warblers. Also, note the gray head and faint gray chest band. There’s no other warbler with this pattern either. Some young birds lack the black flank streaking, but otherwise have the same overall pattern and still look pretty distinctive.

Prairie Warblers are found mostly in the Eastern U.S. These warblers are usually quite easy to identify by the face pattern alone. Note the black eyeline and semicircle below the eye. Let’s look at that. See the black eyeline and then this little black circle underneath. That’s a Prairie Warbler characteristic. Additionally note the black flank streaking and rusty stripes on the back. On the less vibrant birds notice the same overall pattern, it’s just a faded version of the adults. The dark eyeline and semicircle are still apparent.

Canada Warblers are found in the Central and Eastern U.S and Canada, they also show up as vagrants in the West. This species is very distinctive. The adult male with a black necklace striping is a beautiful bird. Also note the mixed white yellow eyering, really it’s got yellow on top and white underneath. That’s kind of odd, if you can get to see that, it’s kind of cool. Also it’s got plain, slate-gray upperparts. Young birds lack the distinctive black necklace, but show the same overall pattern. And if you look really closely, on this little guy, you can see that there’s still this little necklace of streaks although it’s very difficult to see, but it’s still there.

Cape May warbler is found mostly in the Central and Eastern U.S. and Canada. The bright birds are relatively distinctive, but look for the overall color pattern as well as the more specific field marks. Note the yellow neck patch, dark streaking across the chest, and the white wing patch. 
Young females are much less colorful, but still distinctive. Note the overall brownish-gray plumage with yellow green accents on the edges of the flight feathers, rump, and face. The streaking is similar to brighter birds with streaking across the chest and down the flanks.

Blackburnian Warblers are commonly found across the eastern U.S. and Canada with vagrants occurring throughout the West. In the spring this is a spectacular bird with a blazing orange face, but in the fall it’s a little more muted and a little hard to identify. Overall Blackburnians are dark above and pale below. Most importantly, notice the facial pattern. The dark cheek is set off by a broad orange supercilium and throat, and a pale under eye arc. Let’s look at that closely, because this is an important face to remember. Also note the striping on the back. Most fall birds are less colorful, but still share the same field marks. Pay attention to the same facial pattern and the light streaking on the sides.

Yellow-rumped Warbler is one of the most abundant warblers and is found throughout the US and Canada. There are two subspecies in our region the Myrtle that’s widespread and the Audubon’s that’s found primarily in the west. The main field mark to look for on all Yellow-rumps are the yellow patches on the sides of the chest, and a yellow rump on a streaky warbler. Myrtles show a dark cheek with a white supercilium and a white throat, while the Audubon’s shows a more plainly marked head with white eye arcs and a yellow throat. Young birds are less vibrant, but you’re still looking for the same field marks: a yellow patch on the side and a yellow rump on a streaky warbler.

Palm warblers are mostly found in the Eastern U.S. and Canada. They’re two subspecies: Western and Yellow. Both of which are found in the East, but the yellow is more restricted to the far East and the Western is further to the West. On either, notice the yellow undertail and uppertail coverts. Also note the indistinct streaking down the sides and the facial pattern. Less vibrant birds are more brown overall with the yellow uppertail and undertail coverts contrasting with the rest of the plumage. Also note the indistinct streaking in the face pattern. These field marks combined can only be found on Palms. And this one has another behavioral clue, they constantly bob their tails. A little bit more, I think, than the Kirtland’s Warblers, but pretty much in the same fashion.

Okay, quiz time! Which members of the “Streaked Yellow Warbler Group” are these? Polls open give it a go.

Okay the poll’s ending soon get your answers in. Definitely streaked yellow warblers.

Okay, let’s see how we did. Alright, well, this first one seems to be a little difficult, but it’s a Palm Warbler. You can tell yellow undertail and uppertail coverts and that facial pattern of streaks through the face. Just over half of the people got that right though, so doing well. Let’s try the second guy, that’s a Magnolia Warbler. See the streaks and that little bit of a dark band across the chest. And about two-thirds of the participants got that, too. So, great! Doing well!

Let’s move on, next up we have the “Cold-toned Streaked Warbler Group”. All of these species have wingbars, lighter fine streaking, except for some of Black-and-white’s where it’s thicker. And are a mixture of blacks, whites, and blues in the case of the Cerulean Warbler. To identify birds within this group pay attention to the pattern of the undertail coverts, back streaking, and the color and pattern of the throat and chest.

Black-and-white Warblers are widespread through the Eastern and Central U.S. and Canada. Their habit of creeping on tree branches, like nuthatches, is unique among warblers. 
All you really need to remember about this bird is that it’s striped black and white, from the head to the back as well as below. And it even has streaked undertail coverts. This is one of the characteristics I find most amusing. There are less contrasting birds, but they only differ in less streaking below and are buffier overall. This is a pretty distinctive warbler

Black-throated Gray [Warbler] occurs mostly from the Rocky Mountains to the Pacific Coast and only slightly into Canada. This is another distinctive warbler. Adult males have a strong black and white head pattern. Other plumages lack the black throat and overall contrast, but have the same basic field marks. And all plumages can be identified by their overall black, white, and gray pattern with what’s called a yellow supraloral spot, that means it’s above and in front of the eye. A little yellow spot above and in front of the eye. And you can see the male has it, the duller bird has it and the dull juvenile does as well.

Cerulean Warbler is only commonly found in the Eastern United States and is most common in the Southeast. Adult males are distinctive with the combination of cerulean blue above, white below, and a dark neck band. Females and young birds are more tricky and don’t have as obvious of field marks. The light blue wash above is a giveaway if you can see it. Also note the pale yellowish wash on the throat and distinct supercilium, as well as the unmarked undertail coverts.

Okay quick quiz on this one, which members of the “Streaked Cold-tone Warbler Group” are these? Polls open.

Okay the polls are ending soon get your choice in. 

Let’s see how you did. Alright, we have the answers and you guys are definitive, the first one is a Black-and-white Warbler. Nice streaky, little streaky mask and look at those undertail coverts. I love that, I just think it’s so unusual and interesting to see that kind of pattern on a part of the bird that you don’t really think of as being very well marked. And almost everybody got that, 93% of the people got the Black-and-white Warbler. 

And the second bird is the Black-throated Gray Warbler with sort of gray on the back and that yellow spot in front of the eye, the supraloral spot. And 87% of attendants got that, so very good, very good, this one must have been an easy one.

Alright, next is the “Yellow-faced Warbler Group”, the shared characteristics between the birds are the yellow heads with varying facial patterns and black throats. They also have wingbars and white tail spotting. To identify the birds within this group pay close attention to the face, the chest, and the back pattern.

Townsend’s Warbler are common throughout much of the western U.S., through Western Canada and into Alaska. Adult males are very distinctive with the strong black and yellow face pattern, black crown and throat, and yellow extending to the lower chest. Females and young have the same overall pattern, but they lack the black throat and such a high contrast in the head pattern. However, the face pattern, dark side streaking, and yellow reaching the lower chest are enough to identify this plumage as a Townsend’s Warbler. It’s got the same pattern as the bright male, but it’s just a little muted.

Hermit Warblers are found along the West Coast in the Southwestern U.S.. Adult males are very distinctive with their yellow face and crown, and black throat. This is the only warbler with this pattern. Also note the clean white below with no yellow. They’re also quickly identifiable in their less vibrant plumages. Still notice the yellow face but with a Dusky cheek now, and clean white coloration below, and the grayish-olive crown. These field marks are diagnostic for Hermit Warbler. 

Black-throated Green Warbler is found mostly in the Eastern U.S. and Southeastern Canada, and they’re a common migrant throughout most of the East. The bright plumages can be identified with a combination of yellow face, and a faint olive cheek, black throat, and all white below the black throat. The less vibrant plumages lack the black throat, but are otherwise similar. And they also still have a good tell, here, which is this yellowish wash near the vent. It’s this little yellow stripe going underneath the tail behind the legs, and if you see that you know you’ve got a Black-throated Green Warbler because it’s diagnostic. Note the lack of yellow through the throat and upper chest that would be present in a Townsend’s Warbler, it’s just white in a Black-throated Green.

Within the U.S., the Golden-cheeked Warblers are only regularly found in Central Texas. On the bright birds, a combination of yellow face surrounded by black, and a black eyeline are just diagnostic. Also note the streaking that extends to the undertail coverts, this can be difficult to see, but it’s a good way to differentiate it from the Black-throated Green Warbler. Less vibrant birds have the same overall pattern, but lack the black coloration and throat. Still note the yellow face with a dark eyeline, a dark malar stripe instead of the dark throat, and the dark streaking extending to the undertail coverts.

Okay, quiz time! Which members of the “Yellow-faced Warbler Group” are these? 
Poll is up, and let’s see what you think.

Okay, here we go. Aright, the first bird, three quarters of the attendance group agree, is a Townsend’s Warbler, showing that nice dark crown, and that dark face mask, and yellow streaking on the chest. That’s good, next up, let’s see how many people also thought, this is a Black-throated Green Warbler. White on the chest, not yellow like the Townsend’s, and just with just an olive bit on the top of the head. And two-thirds of you participants got that one right, so very good, very good.

Next up is what Eric calls the “Hardest Group”! These three warblers are very difficult to identify, they’re yellowish to greenish overall with white wingbars, indistinct streaking below, and indistinct facial patterns. 

To identify the birds within this group pay attention to flank and undertail color, back streaking, and foot color. Yes, I said foot color, you’ll see.

First up is a Bay-breasted warbler and they’re found across the East and in many areas as a common migrant. Start by noticing the greenish overall coloration and the bay wash on the sides of the males this is diagnostic. Also note the streaked back and dark feet. Many fall birds don’t show the distinct bay wash on the sides, but otherwise note the same field marks including the buffy undertail coverts. Most birds do show a slight bay wash on the sides, but it isn’t always present. 

Now the Blackpoll Warbler is the most similar species, but it has white undertail coverts, pale feet, and usually appears more yellowish than a Bay-breasted Warbler. Let’s just look at those pale feet, yep, pale on that, dark on that. This is one of my favorite characteristics of Blackpolls and this group is that the blackpolls have really yellow feet. And you normally don’t think about looking at warbler feet, in fact it’s a challenge to do, but it’s pretty fun in this group.

Blackpoll Warblers are mostly found in the North Central and Eastern U.S. and Southern Canada. Their migration takes them to the Northeast and Mid-Atlantic Coast before they migrate south over the Atlantic, they go from Canada flying straight to South America. It’s amazing. So in the fall, they’re rare in the Southeastern U.S.. 

Adults are grayish overall with a pale yellow wash. This overall plumage is diagnostic. Also note the strong face pattern and pale feet. Young birds are washed in more yellow-green overall, but note the same pale feet and white undertail coverts. The face pattern on Blackpoll is usually more distinct than Bay-breasted. Let’s check out these feet: this guy has almost all yellow legs, but this one has just yellow feet. The back of the legs in some birds actually only have yellow palms, the soles of their feet are yellow and the rest of the legs are dark. But they’re still there, which is kind of cool. Bay-breasted is, of course, the most similar species and note the bay tinged sides not all birds have, but buffy undertail coverts and dark feet.

Next up is a Pine Warbler and these are mostly found throughout the Eastern U.S. in adjacent Southern Canada. The bright birds are distinctive with their unstreaked olive backs, strong yellow eye arcs, and blurry olive streaking on the sides. Young birds can be very dull and not show any yellow, but note the same face pattern, unstreaked back, and white wingbars.

Okay, quiz time again! Which members of the “Hardest Group” are these?

Alright, getting close to time to close the poll. So get your answers in and we can look at the results.

Okay, we’ve got some answers now, and the first one up is a Pine Warbler, and you can see it has sort of blurry olive streaks on the sides and those nice distinct eye arcs. It definitely is the one in this group that has the most distinct eye arcs. And about two-thirds of the people got that one right, that’s good, so a little more confusing perhaps. And the next one is Blackpoll Warbler, it’s kind of a wash across the face and everybody, three-quarters of you probably notice the yellow feet that I’ve been going on so much about. So, good for you guys.

Next group are the “Yellow-throated Warbler Group” and they’re distinguished by their bright yellow throats, overall blue-gray plumages, and black and white pattern around the eyes.
To identify the members within this group pay attention to the facial pattern, the back color, and the flank streaking.

Yellow-throated Warbler is mostly found in the Eastern U.S. and most commonly in the Southeastern U.S.. They’re very distinctive with their overall color pattern. Note the black face triangle, the white lower eye arc, and that yellow throat. The only similar species is a Grace’s Warbler, but they don’t regularly overlap in range. Note the lack of the black triangle on the face pattern, and the thick yellow supraloral above the front of the eye. That is, it’s got a big yellow stripe above and in front of the eye.

Grace’s Warbler is only found in the Southwest U.S. and into Mexico, with vagrants regularly showing up along the southern California Coast. As we talked about on the last slide, note the thick yellow supraloral stripe and under-eye arc, as well as the yellow throat that goes to the lower chest. Even when they’re less vibrant they’re distinctive, note the overall pattern and lack of black sideburns. The Yellow-throated is the most similar, like we talked about, and one last thing to note is they have a white supercilium that’s pretty thick. So not a yellow supraloral, a big thick white supercilium or eyebrow stripe.

Northern Parula is mostly found in the Eastern U.S. and Canada, they’re regular vagrants to the West Coast. The combination of bluish-gray with a greenish patch above, white eye arcs, yellow throat, and dark chest band are diagnostic for Northern Parula. Some birds are less colorful, but the same field marks can be used. Some birds will show a greenish wash to most of the upperparts, but that mixed with the blue-gray is diagnostic.

Okay, quiz time again! Which members of the “Plain Yellow-throated Warbler Group” are these? Polls open. Give this a guess.

Streaky not streaky, but yellow throats for sure.

Alright poll’s closing get your last votes in.

Alright, I like this 80% of you guys participated, that’s great, that’s great. So let’s see how you did. The first one up is a Northern Parula and 82% of you guys got that, mainly it has that nice chest band, and the eye arcs, two eye arcs, and no streaking on the side. So that’s the Northern Parula. And the next one up is a Grace’s Warbler and again about three-quarters of the group got that right. It definitely belongs in the “Yellow-throated Warbler Group” but it has that yellow line above the eye, instead of white like a Yellow-throated, and does not have a black triangle on the face, the sideburns, that the Yellow-throated would have. Alright, very good.

Our last group is what Eric calls the “Outlier Group” or what I would call the others. Since these are outliers they don’t have many characteristics in common, but they’re all distinctive in their own way.

The Black-throated Blue Warbler is mostly found in the Eastern U.S. and Canada. Males are distinctive with their deep blue above, black throat and flanks, and the white base of the primaries sometimes called the white pocket handkerchief. You can see this here, it’s not really very obvious, but it’s an important characteristic. Females are less distinctive and often confused with many other species. And in fact, they were thought to be two different species when they were first described and it took ornithologists a while to figure out “oh, there’s just male and female”. However, if you remember a few field marks it also becomes easy to identify the females. Note the brownish Olive overall coloration, a thin pale eyebrow and under [eye] arc, and that white spot on the wing (they have the white pocket handkerchief in all plumages). So, also you can note on this particular individual there’s a thin hint of blue on the tail that links them to the male Black-throated Blue.

American Redstarts are widespread across the U.S. and Southern Canada, but they’re most common in the East. Adult male American Redstarts are very distinctive. Note the black overall, with a white belly, and orange accents on the side of the chest and on the base of the wing and tail feathers. All of this is diagnostic, you just don’t see a bird that looks like that, to be confused with an American Redstart. Young birds and females can be more confusing however, but the combination of orange or yellow spots on the side of the chest, and at the base of the wing and tail, are diagnostic. Some birds do lack the color at the base of the wing though.

It can be difficult to see in these photos, but there’s an important characteristic is a dark tip to a light tail that looks sort of dipped in ink like a Magnolia Warbler. These are the only two of our warblers that have this characteristic. As I said it’s a little hard to see here, but you can see the abrupt black start there. And on the top the yellow doesn’t go all the way through, but you can see distinct black tip to the tail.

Painted Redstarts are only regularly found in Arizona and New Mexico and south of the border. They also can show up quite often in Southern California as vagrants. Adults are easy to identify, note the black overall plumage, the red belly, and big white patches in the wings and tail. The young birds, the juveniles, lack the red belly of the adults but are still readily identifiable. Note the black overall coloration, the white under eye arc, and white patches in the wings and tail. A pretty distinctive bird.

Another distinctive bird is a Red-faced Warbler. These are only regularly found in Arizona and New Mexico and south of the border. This is distinctive in all plumages. Note the beautiful red head with the black- what Eric calls “headset” marks, and the pearly white rump. They can be less vibrant, but always show the same diagnostic field marks.

Chestnut-sided Warblers are mostly found in the Eastern U.S. and Canada, and there are also many vagrant records from the Western U.S. All the plumages are distinctive, but the adult male is especially so. In the spring, it has a dark chestnut running up the sides like “Chestnut-sided”, but in the fall it loses that, but it still keeps a nice big patch of dark chestnut on the flanks. The greenish-yellow color above is unique and the white eyering adds to its distinctiveness. Young birds and females lack the chestnut side patch, but otherwise they look the same. Note the same greenish yellow color above, yellowish wingbars, and pearly gray coloration below. Also note the cocked tail which is a behavioral tell. Chestnut sided warblers cock their tails up constantly, other warblers only do it now and then.

Golden-winged Warbler is mostly found throughout the Eastern U.S., and this is another very distinctive warbler. Males show the black face mask and throat, and in addition a yellow cap, and a yellow wing patch and all of this is diagnostic. The females have the same overall pattern, but instead of a black face mask and throat it’s grayer, but it still contrasts. Note all the same field marks, and this is actually a pretty easily identified warbler species.

Okay quiz time which members of the “Outlier Warbler Group” are these? Everybody play, poll’s open.

Okay, it’s about time to close the final poll. So get your answers in quickly if you haven’t done so yet.

Alright that’s about it, let’s see what happened in the final poll. What are these birds and how did you do?

Alright, the first one was a Painted Redstart and yeah, 9 out of 10 of you guys got that one right. It’s a Painted Redstart, it looks like a painted bird, it’s got big white patches, big red patches, black, and if you can’t see that you can also look for that little under eye arc on the black face. The other bird is a female Black-throated Blue Warbler and again 90% of you guys got that. Very subtle but having the little face pattern with the eyeline and under eye arc, and that white pocket handkerchief on the wing. Very good, very good.

Okay, that wraps up our presentation. I hope you enjoyed it and now I think we’ve got enough time for me to entertain some questions. I know we covered a lot of material, but remember we’re recording this webinar and we will make the recording available to you in about a week; and you can look at it as many times and as slowly as you’d like to.

[Samantha Hauser] Okay, great! So go ahead and drop your questions in the Q&A, reminder please don’t put them in the chat we won’t see them. To start us off we have a question: Why are some warblers dull in the fall?

[Kevin McGowan] Well, most of the warblers are duller in the fall partly, because the adults are trying to look pretty. The males are trying to attract the females, and attract a mate in the spring. And being attractive and showy has a downside in that it makes you more vulnerable to predators. So, that’s why you can afford to be showy if you’re just trying to breed, but it’s better to not be if you want to stay alive. Different priorities in different seasons.

[Samantha Hauser] Another question we had was: Why don’t they sing in the fall? 

[Kevin McGowan] Sing in the fall, thank you. There are, some warblers do sing in the fall, but not very much. And those are usually young males that are just learning their songs or are practicing their songs, their songs are starting to crystallize. And again the reason that most of them don’t sing is that singing is used for two main purposes: one is to attract mates and the other is to defend territory. And in the fall most of these birds are moving through, they’re not in their final wintering spots, and so they aren’t really holding territories while they’re coming through. And they’re not trying to attract mates, so there’s just not much point.

[Samantha Hauser] Great! And from Brenda: what is the most endangered warbler in the U.S. and Canada?

[Kevin McGowan] Most endangered, well the Kirtland’s Warbler was and probably still is. It was certainly down to the lowest population, it was an interesting story that they breed only in Jack Pines forests of a certain age. If they’re too small they won’t come in and if they’re too big then they leave. And that takes fire, they’re a fire maintained habitat and a fire maintained species. And in the 1960’s they dropped down to I think it was fewer than 100 birds. And there was a lot of effort made to get the populations back, and they’re back, they’re still not huge. They’re still rather small populations, but at least it’s… I’m not sure, did it come off the endangered list? Or is it threatened, or is it still declining? I know they’ve been actually expanding their ranges a little bit, I mean there are only a few birds here and there that have turned up in Ontario and Wisconsin outside of Michigan. Actually we had one singing, I think we’ve had a couple in New York. That the birds have actually, you know, increased enough that they’ve been prospecting in other places. But that’s, I pretty much would say, is still the most endangered warbler in North America, because Bachman’s Warbler is gone (went extinct probably in the 1960’s).

[Samantha Hauser] Alright, next question is from Kelsey: do warblers ever hybridize?

[Kevin McGowan] Do warblers ever hybridize, yes indeed they do. There are several species that are very well known for hybridizing and in fact the the Blue-winged and the Golden-winged Warblers, even though the Blue-winged Warbler is, you know, an all yellow one with a low black eye stripe, and the the Golden-winged looks like a duded-up chickadee. You know, they look very different, but they actually are extremely closely related and share the bulk of the same genome. And they hybridize quite a bit, and in fact that’s been a problem for the Golden-winged Warblers that fewer and fewer… they’re being pushed out of a lot of habitats by the Blue-winged Warblers that are taking over, and they first start being washed away by hybridization so to speak. And so, yes that’s a very well-known, very well studied group of birds that hybridize, but we’ll find some weird things that pop up every now and then: Mourning Warbler and [Common] Yellowthroat. Also, Townsend’s and Hermit Warblers, there’s a big hybrid zone in the western region where those two meet in the U.S. Northwest. So, yes, there are a lot of hybrid warblers. In fact I just saw the first, my first time seeing this, I think they’re only 43 photos of this hybrid in the Macaulay Library and I think they were all taken at the same place. A hybrid Colima and Lucy’s or Virginia’s warbler, I forget I think it’s Lucy’s or one of the other two gray warblers anyway. So yes lots of hybrids, here and there.

[Samantha Hauser] Great thank you: do we know why there are so many more warbler species in the East as opposed to the West?

[Kevin McGowan] It probably has to do with the continuous forests, and the fact that- one could say that it had to do with perhaps the glacial patterns of, the retreat of forests without being, I mean- there’s just a lot larger hunk of habitat in the East than in the West, it’s not broken up. But sometimes that stuff is just historical rather than having any real functional explanation. But we know from studies that certainly the northern forests in the Northern U.S. and into Canada hold and support a large number of species all in one place. And that the birds can break up the forest into different subhabitats and make their living. And I think there’s just the available niches in a given place are larger in the Eastern huge contiguous forest and in the boreal forest, than in the West. But that’s really just a guess.

[Samantha Hauser] Great, Adelene would like to know: how to determine a male from female Black-and-white Warbler?

[Kevin McGowan] In the Black-and-white Warbler that we showed was, these are all fall birds. We didn’t actually show any spring birds in the mix here tonight. And the male usually has a black mask, a solid black mask in the spring and then that turns into a sort of a broken mask in the fall, and the females are usually just white across the face. So that’s the easiest way to tell them apart, look them in the face: male has a lot of dark and the females has a lot of white.

[Samantha Hauser] All right, next one, Eli would like to know: Do all members of the Parulidae family migrate nocturnally?

[Kevin McGowan] That’s an interesting question. I think they do, I’m trying to think if I know of any warblers that migrate during the day. And I can’t think of one that does. Certainly a lot of them, the big bulk of them, we’ve learned a lot of their chip notes that you can hear, nocturnal flight call notes, and we certainly seem to get everything recorded during the night. But it’s an interesting question and I wouldn’t be surprised if there were, you know, if you go into South America where there are different kinds of migration (you know, altitudinal migration and things like that), where that would be different. But yes, it seems like all the North American ones are pretty well adapted to migrating at night.

And let’s give it up for the Blackpoll Warbler flying from Canada straight down to South America in one flight. That’s just as impressive as all get out, talking of warbler migration, that’s like the super, biggest one for me, it’s just like, “really? they really do that?” and they really do! I’ve lived in Florida for a number of years and I don’t think I ever saw Blackpoll in the fall.

[Samantha Hauser] It’s pretty amazing bird migration. Okay next one, Grace would like to know: are these groups also more closely related? The groups within our presentation that is, more closely related within the genus or are they just sectioned off by appearances?

[Kevin McGowan] They’re just pretty much sectioned off by appearance, I think I neglected to give Eric enough credit, that I think if you wouldn’t mind at some point, Sam, mentioning what he did with all this stuff. This is mostly his conceptions of how you break them up to make things simpler. There’s so many warblers that it’s hard to just, you know, pick one out of 43. And this is also my philosophy of birding too, is that you don’t just identify a bird just by recognizing it unless you’re really experienced with them. But mostly what we do is say, “okay, well I know that it’s got yellow in it, and it’s a warbler, and it doesn’t have any streaking on it,” then you narrow it down to a smaller group. And then you only have to decide between 5 birds instead of 48 birds. And so this is his concept of what are the groupings that you would see, and maybe confuse in the field. And I think it’s a very good concept of having to do this, there are few that are closely related: the Black-throated Green and that group, those are probably very closely related, but a lot of them really aren’t, they just look alike.

[Samantha Hauser] Great, next question is from Ariel: where do they sleep while traveling? do they make shift nests each night or just find somewhere good enough? 

[Kevin McGowan] Well most birds do not sleep in nests. That’s sort of a common misconception, because that’s what we’ve seen in all the cartoons growing up, is a bird sleeping in their little nest like little homes. And most birds don’t do that, I mean nests for most birds are only a cup for eggs and young babies that can’t fly. And as soon as they can fly, you get them out of there and take them somewhere else. So most birds are actually sleeping on branches. Some sleep in holes, but most of them sleep just on a branch somewhere. And so when these birds are migrating they’ll be perched someplace in a tree, usually well in cover and you know protected from the elements, but still sitting out on a branch.

And birds have a special mechanism with the tendons in their legs, so that when their leg is bent, compressed, that the hind toe actually grips because of the way the tendons are–they don’t have many muscles in their lower leg at all; it’s mostly done by tendons. And so when the weight comes off the toe lets go, and when the weight comes on the toe actually grips the branch. So it helps them keep from falling off a branch. Think if you tried to sleep standing up that wouldn’t work very well, but the birds do it pretty well.

[Samantha Hauser] Alright next question: do warblers molt twice per year to achieve these different colorations?

[Kevin McGowan] I’m trying to think, I know they don’t do two complete molts. I think they only do one complete molt, meaning that when they molt their flight feathers. I’m not sure. I think most of them do one complete molt and one partial molt to change the body feathers, but that’s actually one of those things, some birds, different birds do different things. And some of them change their plumage colors just by having the tips of the fresh feathers wear off. Like a [Northern] Cardinal when they first put on their feathers they’re still red, the males still red, but it’s a duller red than it is in the spring and that happens because the dull tips to the feathers wear off to reveal the brighter color below, but I’m actually… I’d have to look it up for warblers.

[Samantha Hauser] Next question from Daniel: how do you identify the birds in the field, without photos, when they are so fast?

[Kevin McGowan] Well, a lot of times you don’t. I got three very bad looks at three good species of warblers today, on my lunchtime walk, and it’s very frustrating. That’s one of the things about fall warblers. It’s not just that they’re duller and more confusing in plumage, but there are all these leaves out there in the fall that aren’t there in the spring when they come back. And so it’s a challenge, it’s a challenge and that’s why it helps to know the birds fairly well. And then when you, once you’ve learned what they look like you can recognize them instead of trying to pick out all the 10 field marks to identify them. And this is one of the things that’s difficult, you sort of have to have experience. And one of the things that we have in our ID Courses here in Bird Academy, is that we have a tool, a relatively recently developed one, called Snap ID that we use in the Warblers course. Which is that we have a setup of a quizzing system where we’ll give you two photographs when we’re talking about a single species. We’ll give you two photographs, one of them is the bird that we’re talking about, another one is something that looks like it but isn’t it. And so you can go through 10 matches like that and get the answers, but then when you say do it again, it gives you 10 completely different matchups that you can then get these constant comparisons and seeing the birds from different angles at different times of year. And that we hope is a way that people can actually gain experience at home that they can then take out into the field and start to recognize these birds rather than trying to find all 10 things to check off on the list. So it is a challenge and, you know, we’re trying to help people solve that challenge, but the only way to do it is time and effort really. So best of luck.

[Samantha Hauser] Okay we’re going to do one last question, at the time available and we’ll end it on a very happy note from Jennifer: what is the warbler that you have seen that’s been the most rewarding to find?

[Kevin McGowan] That I personally find the most rewarding to find? Well, I would say Connecticut, if I’d seen more than three of them in my life, because they’re so hard to find. But around here one of my favorite warblers is Mourning Warbler. They nest in the hills, well used to not just be the hills but they nest in a sort of in between habitat here in Upstate New York. They were very rare where I grew up in Ohio, I only saw one or two, and here they breed. And they’re just beautiful. But they do live in a transitional habitat that shows up and disappears, and so I, they were very hard to come by this year and I think everybody who saw one really appreciated it. And every time I see one I appreciate it. I appreciate seeing the Common Yellowthroat every time I see it, because they’re so beautiful. But that combination of rarity and you know being something that I did not see when I was a child, it always seemed like a special bird. So for me, I guess that’s what I’d say is for me, it’s Mourning Warbler.

 
[Samantha Hauser] To start us off we have a question submitted about: why we didn’t cover song in this webinar?

[Kevin McGowan] Well, two reasons probably. I mean, I’m talking for Eric because this was his original presentation. But one is that warblers don’t sing much in the fall, so it wouldn’t be very helpful to identify fall warblers trying to do it by song. Chip notes, yes, song no. Because song is primarily used for two things: attracting mates and defending a territory. And they do that in the spring when they’re getting ready to breed, once they’re done breeding they don’t worry about that so much. So that’s just not as important a characteristic for paying attention to this particular time in the field. If we do a spring warbler thing, yes, song will be included. And if you go to our course on warbler identification we cover this song there pretty in depth.

[Samantha Hauser] Alright great. The next question, there were a few people who asked along this theme of: how do we see these marks in the field? that these birds don’t hold still long enough to identify them. 

[Kevin McGowan] Well that’s a challenge, that is definitely a challenge. And that’s, fall warbling is hard, because not only are they dull but there are leaves you have to contend with. And, you know, it’s harder to see the birds than it is in the spring and they’re less obvious, less distinctive. So that’s the challenge. And basically you know it’s, “how do you get to Carnegie Hall? it’s practice, practice, practice” and so you can keep going out there and looking. Also in our course, the Warbler ID course, we actually have interactive exercises called Snap ID where you can- we give you two pictures to choose between in each of the species of interest we have, you know, that species plus something that looks kind of like it. And we’ll give you 10 of those matches that you can choose between, and then you can hit it and do it again and you’ll get completely different matchups with different pictures. Because we put in not just 10 pictures of each species but a number of them, and it randomly picks those to have you compare. And those have pictures with birds at different angles and all of that. And that you can actually practice with so that you can go out in the field having had a little bit of, you know, a step up, head start so to speak, because learning these sorts of birds really does take a lot of practice.

[Samantha Hauser] It sure does. Allright our next question is: can you talk about finding warblers by looking for chickadees?

[Kevin McGowan] Sure, you bet. That’s an excellent suggestion because in the fall as the warblers from Canada come through the U.S., and certainly in the area where in the East where I’m birding most of the time, the warblers participate in these… what’s called in the old world “hunting parties” or mixed species foraging flocks. And so the chickadees are kind of a linchpin species of these flocks where different species of birds get together and move around the forest together. And the warblers come in and start looking for the chickadees, because the chickadees know some of the best places to forage. And so the warblers fly along with them and it’s really a good place to find the warblers. Warblers do make distinctive chip notes, but they’re quiet and kind of hard to learn, but chickadees, you can hear chickadees and you know when a chickadee is around. So if you hear chickadees in September go hang out with them and pish a little bit, and see if there are warblers because there are very often warblers following the chickadee flocks.

[Samantha Hauser] Awesome, we didn’t cover hybrids in this webinar, but some people are asking if there’s any tips on hybrid ID.

[Kevin McGowan] Hybridization, yes, warblers do hybridize; most of the birds that you’ll see coming through are not hybrids. They’re mostly just, you know, each of the species. Although they vary and they can look weird. But warblers do hybridize to a certain extent and you can expect to see some really weird ones every now and then. I mean things like Mourning Warblers and Common Yellowthroats hybridize and a number of other ones. The most common hybrids that people know about are Blue-winged and the Golden-winged Warblers, which hybridize extensively and you can get a lot of hybrid crosses there. In fact, they’re ones that are named because they’re so frequent: the Brewster’s Warbler and the Lawrence’s Warbler, which is really pretty cool. So again if you’re looking at a bird and it just doesn’t make sense, consider hybridization and again look for what does it remind you of which of the pieces looks like something you recognize. And, you know, maybe you can figure out the two pieces that fit together give you this weird hybrid to trace the ancestry back. If you really want to know, take a fecal sample and send it to our lab at the to Irby Lovette’s Lab at the Cornell Lab of Ornithology, because he loves to to figure out these hybrid warblers, and they have a good genetics group that does that on a regular basis actually.

[Samantha Hauser] Alright, backing up a little bit to a more general question: what is the best time of day and location to find warblers?
 
[Kevin McGowan] Well the best time of day for finding birds almost always is in the morning, in the early morning. They’re not singing, you know in the spring and summer that you get dawn chorus where everybody gets up and makes a big noise. They don’t do that in the fall, but they are most active because they don’t forage during the night and they’re hungry when they wake up. And so they’re out and active. Location, it depends on where you are but often, you know, places with trees is good for warblers, because the warblers like the trees. And, yeah, that really depends on your local landscape actually, what are the best places to go. It can be sometimes cemeteries or we have a nice place, the hawthorn orchard, what used to be a pasture and then the hawthorns took over, and somewhere along the line they crowd everything out, but the birds like it. And the warblers are coming through, and we’ve had in the local hawthorn orchard there were, well, I think a dozen warbler species seen this week, something like that.

[Samantha Hauser] Great, thanks, I think this will be our last question: I heard a full moon is useful for looking for migrants, why is that? What is that about? 

[Kevin McGowan] Yeah, full moon is great, because you’ve got a lot of moon there, and migrants. What you may not know is that almost all warblers, maybe all warblers, when they migrate, they migrate at night. And so they’re flying high in the sky and they’re very difficult to detect. But if you’re watching the moon on a good migration night, you can actually see these birds flying past, flying past the moon. And it’s a good way to see how much movement there is. If you look at our Birdcast website that can predict, if you wouldn’t mind putting that link in the chat somebody, the Birdcast actually is looking at the weather and looking at the movements of birds that they can measure with radar and predicting what days will be good or what nights will be good flight nights. And if there’s a- what we’d really like is a good flight night and a full moon on the same night to go out and watch either put a scope on it or use your binoculars. It’s really quite remarkable to see how many birds fly past the moon at night. Actually back in the, I think the 50s or 60s something like that, scientists were trying to use that method to keep track of migration, so, you know, they’d watch it on a regular basis. They’d watch the moon and see how many things flew past, and then you could tell if it was a good migration night or not. And it’s a full moon here right now, tonight I think is it. It’s the peak full moon to go out, if you don’t have clouds, to get out and see what’s going on. 

[Sam Hauser] Great, thank you, so much! It’s hard to believe but 90 minutes have already passed thanks to our audience for such great questions. I’d first like to thank Eric Ripma for his incredible work in designing this webinar and creating the slides. Although he couldn’t join us for the live webinar, the webinar is truly a reflection of his vision. If you’d like to learn more about Eric you can find more information about him through Sabrewing Nature Tours. Kevin, thank you for taking the time to talk with us today and stepping in at the last minute. And lastly thanks to everyone for joining us today. 

Our moderators are currently adding some links for you in the chat, if you haven’t already had the chance to check out our fall warbler reference guide, and if you want to continue learning even more about warblers consider taking our self-paced online Warbler ID Course. You can save 40% with the discount code BAWarblerWorkshop. 

We will be sending out all this information and the reference guide through our post-webinar email, so be sure to look out for it in your inbox. Have a great day everyone, and happy birding.