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Empidonax in Panama (1 Viewer)

SueO

Well-known member
I was torn as to where to post this: ID or Birds and Birding, but I think I will get more feedback here. It's a bit breathy though. I have copied from my new blog:

I have been thinking of splitting my blog, The Twitching Sailor, for some time and it’s ironic that when I finally do, my first post is going to be on a difficult bird and a difficult call as to whether I should have included it on my Life List. I have not put a bird on my list if I wasn’t 100% sure of what it was, until now. There is room for error here and I wonder if that margin should keep me from listing. I began this sailing adventure with virtually no birding skills or knowledge so I have seen my share of birds that I could not list. In fact, I may have the biggest ‘not listed’ bird list in the world! My birding skills have improved greatly over the eleven years I’ve been out on Peregrine, but I am constantly being challenged, and I still come across birds that take me some time to ID. Maybe that is part of the reason so many get obsessed with this hobby; it challenges us on many different levels.
Here is my current dilemma:
The bird is an Empidonax and I believe it is an Alder Flycatcher. In my copy of Ridgely’s , Birds of Panama, he lumps the Alder and Willow together under Traill’s because they are ‘essentially indistinguishable in the field’, although he does say that Alder is said to show more of an eye-ring than Willow. The eye-ring thing is one of the points I have used to validate listing. It doesn’t really show well in the pictures I post here, but I when I saw the bird again this morning (unfortunately, I couldn’t get photos during my 2.5 second and 1.0 second encounters), I saw it in light that allowed me to clearly see an eye-ring. I have gone back several times since the original sighting hoping it would vocalize, but I’ve heard nothing.
I should point out that I have ruled out Eastern wood-Pewee for several reasons. The primary projection doesn’t appear long enough. I have never seen this bird perch higher than a few feet off the ground. It hunts at near ground level, it does not sally out and return to the same perch, and it isn’t vocal. I have encountered Eastern Wood-Pewees here on several occasions and I am confident this is not a Pewee.
Another reason for my going with Alder is the San Lorenzo/Fort Sherman list I often refer to. The list is part of a comprehensive natural resource list of the San Lorenzo Protected Area compiled by Peter L. Weaver and Gerald P. Bauer for the US Forest Service. A note at the end of the bird list says the table was compiled by George R. Angehr and W. Douglas Robinson of the Smithsonian Tropical Research Institute. It lists Alder, but not Willow. I know the list is missing things—I’ve found a few myself--Pale-vented Thrush, White-throated Thrush and Variegated Flycatcher, but on the whole the list is a great and reliable source.
I will continue to visit the site in hopes of getting a sound, but the bird is a passing migrant and I don’t know how long he will be around.
Any opinions or advice?
Sue
 

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This rings a bell, because I found myself in this situation at a site in Costa Rica, where I was told that a bird was an Alder Flycatcher because it was Alder that occurs there and not Willow. Quite annoying as I've only seen Willow! How do we know Willow isn't there? Maybe if it was countless thousands of definite Alders identified in the hand or by voice, and no Willows....but is that the case, or are there heaps of birds recorded as Alder because that's what you're supposed to see there????

Have you seen the thread in the rare bird section on the Alder/Willow that was seen in the UK last year? Someone came up with a way of seemingly proving it was an Alder from photos of the bird by close examination of the wing formula. Maybe that's your best bet. The maths was way way way above my head. Good luck Sue!
 
This rings a bell, because I found myself in this situation at a site in Costa Rica, where I was told that a bird was an Alder Flycatcher because it was Alder that occurs there and not Willow. Quite annoying as I've only seen Willow! How do we know Willow isn't there? Maybe if it was countless thousands of definite Alders identified in the hand or by voice, and no Willows....but is that the case, or are there heaps of birds recorded as Alder because that's what you're supposed to see there????

Have you seen the thread in the rare bird section on the Alder/Willow that was seen in the UK last year? Someone came up with a way of seemingly proving it was an Alder from photos of the bird by close examination of the wing formula. Maybe that's your best bet. The maths was way way way above my head. Good luck Sue!
Thank-you, Larry. I have not seen that thread. I'll look for it. Maybe someone here will be able to do the math for me, it's never been my best subject. ;)
 
The Alder/Willow Flycatcher problem isn't just limited to Florida, I see. Of all the Traill's Flycatchers that migrate through Florida, nearly every single one that has been calling is an Alder Flycatcher (there was one calling Willow Flycatcher documented this year). There has also been one documented at a banding station in Miami-Dade several years ago, based on measurements (it was outside the region of overlap between the two species) -- meaning 'a lot of math' isn't going to guarantee an ID, either. However, there are MANY non-calling birds that migrate through the state as well which we leave unidentified.

When I was birding during autumn migration in Texas, I was told that the default (nearly all) the Empidonax flycatchers that move through the area are Alder Flycatchers (based on calling birds).

So where are all the Willow Flycatchers? This is one of the most widespread Empidonax species in the United States in the summer. Where are they all going? Or is it that they do not call during autumn passage while Alder Flycatchers do? Food for thought.

Carlos
 
Here's the thread Sue, it's a bit of a monster!
http://www.birdforum.net/showthread.php?t=181878&highlight=yellow-beelied+flycatcher

There was also lots of interesting discussion on probability too, before the real egghead stuff kicked in. As it was only the UK's 2nd empid it was a pretty big deal, hence the big thread. I guess at the end of the day though, if an east coast empid can turn up in the UK , I wouldn't put it past a Willow to turn up in Panama.

I'm sure many birders (myself included) do count some look-alikes on range, but when it gets as close as your situation, it might get a bit more sketchy! I'm hoping to hear an Alder somewhere one day :t:
 
The Alder/Willow Flycatcher problem isn't just limited to Florida, I see. Of all the Traill's Flycatchers that migrate through Florida, nearly every single one that has been calling is an Alder Flycatcher (there was one calling Willow Flycatcher documented this year). There has also been one documented at a banding station in Miami-Dade several years ago, based on measurements (it was outside the region of overlap between the two species) -- meaning 'a lot of math' isn't going to guarantee an ID, either. However, there are MANY non-calling birds that migrate through the state as well which we leave unidentified.

When I was birding during autumn migration in Texas, I was told that the default (nearly all) the Empidonax flycatchers that move through the area are Alder Flycatchers (based on calling birds).

So where are all the Willow Flycatchers? This is one of the most widespread Empidonax species in the United States in the summer. Where are they all going? Or is it that they do not call during autumn passage while Alder Flycatchers do? Food for thought.

Carlos

Hi Carlos,
From what I've read, the time to hear Alder's is during the northward passage. I'm not sure, but I think the Alder is rather quiet during fall migration and in its winter territory. Also, small numbers of Willow apparenty winter in Panama, but not Alder. The Willow is supposed to be vocal in winter and on spring migration.
Sue
 
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Here's the thread Sue, it's a bit of a monster!
http://www.birdforum.net/showthread.php?t=181878&highlight=yellow-beelied+flycatcher

There was also lots of interesting discussion on probability too, before the real egghead stuff kicked in. As it was only the UK's 2nd empid it was a pretty big deal, hence the big thread. I guess at the end of the day though, if an east coast empid can turn up in the UK , I wouldn't put it past a Willow to turn up in Panama.

I'm sure many birders (myself included) do count some look-alikes on range, but when it gets as close as your situation, it might get a bit more sketchy! I'm hoping to hear an Alder somewhere one day :t:
Thanks for the link, Larry. It will probably be over my head, but it will be a good lesson no doubt.
 
I'm off for an evening stroll of Mr. E's temporary territory. Here's another picture.
Sue
Edit: Oops, by the time I got things in order the thunder began to roll and the rain began to fall. Oh, well, I guess I'll just have to have a few Cuba libres and appetizers instead.
 

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Hi Carlos,
From what I've read, the time to hear Alder's is during the northward passage. I'm not sure, but I think the Alder is rather quiet during fall migration and in its winter territory. Also, small numbers of Willow apparenty winter in Panama, but not Alder. The Willow is supposed to be vocal in winter and on spring migration.
Sue

Sue,

Alder Flycatcher definitely calls here in the fall. It is seen (and heard) annually in moderate numbers during autumn passage in South Florida.

Carlos
 
Thanks for that information Carlos. Maybe they're still in summer mode while in the US?;) I have decided to remove the bird from my list. I won't be happy with it. If everybody had come on and said, "Definitely an Alder, Sue.", I would have left it. Some other time perhaps. Funny, but on the same day, I got another lifer--a Yellow-billed Cuckoo. Back in 2008, while we were visiting my husband's mother in Arkansas, we went to a bird fair. A tour was offered and we went. It is the only guided bird walk I've ever taken. One of the birds he pointed out was a YB Cuckoo. I didn't put it on my list because the only view I got was a quick flight view and I didn't think it should count because I might not have seen it. On that same tour there was a Little Blue Heron and a Prothonotary Warbler. I didn't list them at the time either. I got the Heron in the Caribbean and the Warbler here.
Who knows, maybe 3 years down the road, I'll be out of California visiting somewhere and an Alder Flycatcher will land in the shrubs in front of me and sound off.
Thanks for your insights.
Sue
 
With those photos, you just might be able to make those wing and beak measurements for a positive ID.

Alders definitely call on their wintering grounds- have heard them quite a bit in southeastern Peru. I bet Willows will too. Yeah, so where are the Willows? Maybe they migrate at a different time and get overlooked because of that?
 
This rings a bell, because I found myself in this situation at a site in Costa Rica, where I was told that a bird was an Alder Flycatcher because it was Alder that occurs there and not Willow. Quite annoying as I've only seen Willow! How do we know Willow isn't there? Maybe if it was countless thousands of definite Alders identified in the hand or by voice, and no Willows....but is that the case, or are there heaps of birds recorded as Alder because that's what you're supposed to see there????

Have you seen the thread in the rare bird section on the Alder/Willow that was seen in the UK last year? Someone came up with a way of seemingly proving it was an Alder from photos of the bird by close examination of the wing formula. Maybe that's your best bet. The maths was way way way above my head. Good luck Sue!

I would mark that one down as a "Traills" because both actually pass through the country as migrants (as is indicated in Garrigues and Dean) and the Willow is actually the species expected during the winter months.
 
Hi Sue,

This:

http://www.birdguides.com/webzine/article.asp?a=2337

might be a quicker link.

A bit complicated - and you have to hope your bird fits nicely on one side of the line as in the example!

H
Hi H,
Honestly, I have to wonder about these numbers games.:-O The lengths of all parts measured seem to overlap on both birds. An extreme example of either species could show as either bird, right?
I have taken the bird off the list, but the fat lady hasn't sung yet. She is temporarily gagged at the moment due to rain, but as soon as I can, I'm going back out. I hope to get a call.
I was up until wee hours last night reading and thinking about these birds. I couldn't help wonder why they weren't simply considered the same bird, why were they split in the first place? If they were different, then what could I look for to try and distinguish them other than appearance? Normally that would be vocalizations, habitat, distribution, nesting habits, favored foods, hunting methods. Unfortunately for me, many of these points aren't any good as this is not the breeding range and they (for the most part) are simply passing through.
Since I am locked below, I have made use of my time by google birding rather than watching in real world. I have played the calls of both numerous times, I have learned why they were split, I have tried to get some DNA info to see if it jibes with the split based on vocalizations. I've learned the the call is innate and supposedly that is part of the justification of the split. (I'm not so sure that birds, even flycatchers, aren't capable of variation. They're living things, not robots.)
I have fried eyeballs, and I have answered many of the things I wondered about, but I am still in the same place I was in yesterday. I have to hear the bird.;)I am writing up my observations even if I can't ID the bird. Yesterday, I saw him come up from the ground with huge bug, grasshopper, I think. Unfortunately, he saw me and was gone in no time. I don't even know if he dropped the bug or took it. It seems improbable that he could have flown so fast with a bug as big as his head in his mouth. I worried that my presence had lost him a meal. He is very fast and I am sure it is him I see fly low and fast from one spot and literally dive into the understory without seeming to slow down.
 
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With those photos, you just might be able to make those wing and beak measurements for a positive ID.

Alders definitely call on their wintering grounds- have heard them quite a bit in southeastern Peru. I bet Willows will too. Yeah, so where are the Willows? Maybe they migrate at a different time and get overlooked because of that?

Hi Patrick,
I have my fingers crossed and the call burned into my brain. If I get a break in the rain, and the bird stays, I may get lucky.

"Yeah, so where are the Willows? Maybe they migrate at a different time and get overlooked because of that?"
I ran across something last night that mentioned Willows preferring the Pacific side. I've read so much, things are a bit blurry. My next search is going to be migration routes. Maybe this is why the Willow is not shown on the San Lorenzo Protected Area list? Maybe it doesn't come down the Caribbean side? I will try to find something on that.

Sue
 
With those photos, you just might be able to make those wing and beak measurements for a positive ID.

Alders definitely call on their wintering grounds- have heard them quite a bit in southeastern Peru. I bet Willows will too. Yeah, so where are the Willows? Maybe they migrate at a different time and get overlooked because of that?

Patrick,
This is what I read regarding the Pacific side. This pertains to California, although the range of the Willow in other states is mentioned. California has three ssp of Willow to add to the mix.;)

http://www.prbo.org/calpif/htmldocs/species/riparian/willow_flycatcher.htm

Not far from the top of the page on the above link, you will find WINTER DISTRIBUTION:
WINTER DISTRIBUTION
The winter range (all subspecies) extends from Nayarit and southwestern Oaxaca, Mexico, south to Panama and possibly extreme northwestern Columbia (AOU 1998). Willow Flycatchers prefer pacific slope, arid scrub, and brushland habitats (Fitzpatrick 1980). There is no clear evidence that the subspecies of Willow Flycatchers segregate on the wintering grounds (Unitt 1997).
E.t. extimus: Examination of museum specimens of 578 migrating and wintering Willow Flycatchers located three definite and eight probable specimens of E.t. extimus indicating that Guatemala to Costa Rica constitutes the main winter range (Unitt 1997).

Do the Willows who summer in the North-east, fly west before migrating south?:
http://ebird.org/content/ebird/about/occurrence-maps/willow-flycatcher
 
In Panama I would have thought the Pacific/Carib split becomes more blurred anyway - especially in the canal zone.
Hi H,
I've been staying very late and getting up early and I'm a bit punchy at the moment. I don't understand what you mean. 8-P What I meant about the Pacific side is that in the canal area, some birds that are present on the Caribbean side are not present on the Pacific slope and vice-versa. Where I am on the Caribbean side in San Lorenzo it is wetter than the Pacific side.
Sue
 
Did you ID the bug to subspecies?. Choice of prey might prove to be diagnostic for Willow/Alder ;)

NO! :-C I knew at the time that might be important, but things were so fast. We discovered each other at the same time and it was a startled kind of thing. I'm fairly certain it was a grasshopper because it was so big, but I couldn't swear it. Things have gotten more complicated for me now.
There was a break in the rain last evening and I went out. I found the bird. Well, I found a bird that looked like my bird, but behaved very differently. According to Ridgely, habits of the Willow and Alder are the same while they are here. Last night the bird was perched low in the big grass/reedy stuff like a grassquit or reed warbler. It did sally this time. It shot straight up from its low perch about 15 to 20 feet, caught something and returned to the same area in the grass. The upward flight was straight and the downward path curved so that the pattern was bow shaped. I did hear a Flycatcher 'snap'. In my previous sightings, the bird never went higher than a few feet. On my last view of last nights bird, I had a clear a great view. He had an almost 'necklace' look in the gray on the breast. It was striated in a weak way. Then he saw me watching and took off--up into the canopy! I started to wonder if both species were here and if they didn't behave the same. I'm so confused! To make matters even less clear, I was out this morning and most definitely saw two birds (maybe three). I got a good little video on my camera, but it's new and I can't figure out how to down load it. It didn't download with the pictures. I also think I heard a Willow, but I don't know....there are so many voices out there.
 
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