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Forum birdwatching 2009

davefoc


IMO the plumage is still way too different from that of a juvenile western scrub jay. The iridescence on your specimen is characteristic of a brewer's. Also, I have been to that wild animal park (mainly to see the california condors :)) and have observed brewers hanging around the food areas--this behavior is common at other zoos I've visited.

Thanks for the comment Mako. My wife and I greatly enjoyed our day at the park and we did see the condors which were very impressive. But also a little disappointing. I've seen the California condors in the Grand Canyon and it was one of the more amazing sights that I can remember. It was amazing that any bird that large could fly. It just wasn't nearly as impressive seeing them in cages.

I certainly agree about the plumage. I would never have even considered western scrub jay if somebody else hadn't suggested it. But I lean to thinking they are probably right because of the bill shape and because the people who have suggested scrub jay are very knowledgeable about bird identifications.

I took a look at most of the brewer's blackbird images on the web again. Here's one that looks tantalizingly close:

http://www.pbase.com/ritter/image/55337040

One thing, that I would be curious about is whether there is enough information in the image to conclude that the bird is a juvenile.
 
Kotatsu, we have had a sudden influx of redwing blackbirds at my place! One of them figured out how to cling, almost upside down, to the bottom of the 'little birds only' feeder and make it spill onto the ground; then they all jump down and eat off the spillage. If they weren't so lovely, I'd be really ticked off...

We get Anna's and sometimes Rufous hummingbirds, and once in a while a Calliope. One group is seasonal, and the other is resident. I can't tell you which is which, since until about two weeks ago my hummer feeder was quite a way from the house. (Now I have one stuck to my family room window, which is BOSS, even if Kotatsu almost dislocated his neck trying to look at one...

In addition to the flickers, I had a spot (using binoculars) of a woodpecker-ish bird I did not recognize. It was a tid smaller than a flicker, had dark grey-brown back with some black striping or ticking, and just a smide of red at the back of the top of the head. My best guess is an immature "hairy woodpecker" but I'm not certain at all. And, of course, no pictures...

Also--very happy Miss_Kitt time!-- I had a cedar waxwing a few days ago! Since Kotatsu's visit I have had my binoculars next to the reclining chair I ice my sore back in, so I can birdwatch while I ice...and there he was! I've only seen one once before, so I hope he comes back and brings his buddies. (I wonder, do they like elderberries? My bushes have a ton of berries this year.)

Hello to all, MK
 
The first paragraph here suggests they might be scarce enough to be worth a note to the local recorder, particularly if there's evidence of breeding, depending on where Miss_Kitt's is.

Oh! I'll look into this, then.

Looking in my Sibley Guide, I'd say it's probably a brewer's blackbird. The eye color is a tad deceptive because of the lighting, and some female brewers have dark eyes. Brown-headed cowbirds have stouter beaks so I think I'd rule that out.

I still maintain that this is likely a juvenile scrub jay. Cover the head in the picture with your hand, as the head plumage is either not fully developed yet, or has recently been moulted. That's why the head looks so "rough", and not as smooth a most birds look. Apart from the beak, the head is not representative.

Now, compare with these pictures of (supposedly juvenile) scrub jays:
Number one
Number two
Number three

None of these have the same blue colour of the wings (though #1 comes close), but as that might be light-dependant, and the bird in davefoc's picture seems to be moulting the wing feathers anyway (1) look at the general plumage. Juvenile scrub jays seem to have the same grey-beige colour on the body feathers and head feathers as the bird in the picture, with the blue in the wings and tail appearing before the patterns of the head and chest (2).

This, coupled with the bill -- which certainly looks corvid (or jay-like, at least), though the nasal bristles (or whatever it is called) typical of corvids can't be seen (as opposed to adults), but that may be developed later, or be missing in this individual.

The Brewer's picture Mako posted seems to be between moults, as there are no perceptible "roughness" of the head, no differences in colour among the flight feathers, and an over-all slickness of the plumage, and thus the two birds are not in a comparative developmental stage, but this does not mean that they are not the same species, of course.

However, look at the secondary/primary projection of the two birds. While Davefoc's bird in in moult, the old flight feathers are usually of the same size as the new ones, and the difference is basically degree of frayedness along the edges and mite and louse damage on the barbs (and sometimes the rachis) (3).

In Davefoc's bird, the secondaries (starting with the first blue feather from below) cover the primaries (all brown and stacked) almost entirely; the part of the primaries being visible is we were to stack all flight feathers on top of each other would be slight. However, in Mako's picture, though the wing is in a different position, we can see that the secondaries do not reach nearly as far out onto the outer primaries as in Davefoc's bird.

It is hard to see any more details in Mako's picture (do you have a larger version?), but unless secondary length in Brewer's and/or Scrub is highly variable, I think this may be a useful character in this case. Sphenisc's argument on the bill shape seem to hold for the two pictured birds as well, though the position of the head in Mako's picture makes a direct comparison difficult.

Here is a female Brewer's Blackbird for comparison, and here's and here's some juveniles. If we assume that these are representative, they invariably look different from davefoc's bird. The bill shape, for instance, is different, though the full difference of the bills is not immediately obvious, as davefoc's bird has its head turned slightly towards us. Nevertheless, the bill is longer, somewhat stouter, and does not have the same shape as these Brewer's. Further, in all pictures, the secondaries are much wider and blunter than davefoc's bird (see here, for instance).

Based on these arguments, as well a a general feel for davefoc's bird (which doesn't "feel" like the Brewer's I saw in Bellingham), I would say that davefoc's is a Scrub Jay.

In addition to the flickers, I had a spot (using binoculars) of a woodpecker-ish bird I did not recognize. It was a tid smaller than a flicker, had dark grey-brown back with some black striping or ticking, and just a smide of red at the back of the top of the head. My best guess is an immature "hairy woodpecker" but I'm not certain at all. And, of course, no pictures...

In a moment of idiocy, I placed all my North American field guides in the box with my collection equipment, and sent it home by mail. It will arrive in about a month, and until then I have no reference material. Nevertheless, once I come back from the museum this afternoon, I'll have a look around.

Also: for those of you to whom this might be interesting, I looked through this summer's Molecular Phylogenetics and Evolution today, and found a lot of interesting articles on bird phylogenetics. The most relevant ones would be:
- one on the Acrocephalidae (primarily Acrocephalus and Hippolais warblers) which I did some (uncredited) sequencing for, and which "overthrows traditional taxonomy"
- one on the Saxicola torquatus complex
- one suggesting that the Sandwich tern Gelochelidon nilotica is actually two species.

I haven't read any of these yet, though.

---
(1) I don't know how these birds moult, but there is a difference in colour between the primaries and most secondaries (brown) and the rest of the secondaries and the covers (blue), which suggests that the bird is in moult. Note that this could mean that the bird is not a juvenile, though.
(2) This picture suggests that the white underside and blue patterns on the body appear before the head patterns are fully developed; I don't know the relative ages of all involved birds, though. Nevertheless, I could hazard a guess that they are probably all-grey-beige first, then assume the blue in the wings (and tail?) during the first moult (whenever that is), and first subsequently develop the blue in the rest of the plumage.
(3) Of course, moult can also happen between two different plumages, like in ducks, where the differences between them are more substantial, but unless the flight feathers are secondary sex characters, the size of the primaries and secondaries should be roughly the same in both plumages.
 
Thanks to everybody that has provided such interesting information about the image I posted. I would just like to add this:

One of the reasons that I would never have suspected a scrub jay is that the color in this bird seems iridescent and scrub jay color seems not to be. My understanding of the situation is that bird colors can be produced in two ways: 1. Through pigmentation, that is through the use of chemical colorings that are a particular color and 2. Through the use of mechanical structures that cause particular colors to be reflected through diffraction.

To my eyes, the normal scrub jay blue doesn't look iridescent and the blue in the image of the bird I posted does to my eyes. I would not have expected a bird to be blue through iridescence in some forms and blue through pigmentation in other forms.

None of this is to say that I have anything to add to the identification of the bird in question. I just brought up the iridescence issue because I thought somebody might have something interesting to say about it.
 
Thanks to everybody that has provided such interesting information about the image I posted. I would just like to add this:

One of the reasons that I would never have suspected a scrub jay is that the color in this bird seems iridescent and scrub jay color seems not to be. My understanding of the situation is that bird colors can be produced in two ways: 1. Through pigmentation, that is through the use of chemical colorings that are a particular color and 2. Through the use of mechanical structures that cause particular colors to be reflected through diffraction.

To my eyes, the normal scrub jay blue doesn't look iridescent and the blue in the image of the bird I posted does to my eyes. I would not have expected a bird to be blue through iridescence in some forms and blue through pigmentation in other forms.

None of this is to say that I have anything to add to the identification of the bird in question. I just brought up the iridescence issue because I thought somebody might have something interesting to say about it.

Scrub jay's blue plumage is structurally based. http://www.springerlink.com/content/hj7rl14613h17304/fulltext.pdf. First sentence, so no risk of coma. :)
 
It is hard to see any more details in Mako's picture (do you have a larger version?)

Sorry about that, I should have simply linked to the original here. Also, check out these with "rough" heads here and here. Here's some nice iridescent plumage.

Anyways, thanks for your expertise :)
 
I agree with Kotatsu - it's a Western Scrub Jay.

http://elibrary.unm.edu/sora/om/om029.pdf p6 said:
Molt of the proximal secondaries occurred during August, September, and
October. Some Scrub Jays completed growth of molted secondaries by early
September. Of 42 juveniles examined after 1 September, 41 had molted secondaries 9 and 10, 11 also had molted secondary 8, and one had molted only secondary 10. With the one exception excluded, secondary 9 was molted before 10, and secondary 8 was molted either before 9 or after 10. Secondaries 1-7 are not replaced.

This matches the pattern in davefoc's bird - secondaries 8, 9 and 10 have been replaced.
 
I agree with Kotatsu - it's a Western Scrub Jay.



This matches the pattern in davefoc's bird - secondaries 8, 9 and 10 have been replaced.

Direct link to sphenisc source:
http://elibrary.unm.edu/sora/om/om029.pdf

This article inspired me to spend time reading through the various Wikipedia articles on feathers so that I might have a better chance of understanding what sphenisc is talking about.

Among the weird facts that are now floating around in the davefoc brain is that remex is the singular of remiges. Besides that little factoid there was quite a bit of interesting information about the structure of bird wings and the terminology to describe them in the Wikipedia articles. If anybody has an interest or you want to know what the singular of rectrices is you might check out these:
http://en.wikipedia.org/wiki/Flight_feather
http://en.wikipedia.org/wiki/Feather

As to the substance of what sphenisc said:

OK, I get the idea that the secondaries are the flight feathers (remiges) which are the feathers that are attached to the ulna. But how can you tell by looking at the image in question that the secondaries, 8,9, & 10, have been replaced? If the bird, has indeed gone through at least part of one molt, does that mean it is possible to conclude the bird is at least one year old?
 
It was a busy morning for the birds at my home in Macedonia, OH, USA today. Nothing new to the list, though one new for the year for me...

American crow – Corvus brachyrhynchos
American robin – Turdus migratorius
Blue jay – Cyanocitta cristata
Black capped chickadee – Poecile atricapilla
House sparrow - Passer domesticus
Killdeer – Charandruis vociferous
Mourning dove – Zenaida macroura
Northern cardinal – Cardinalis cardinalis
Northern flicker – Colaptes auratus
Ring billed gull – Larus delawarensis
White-breasted nuthatch – Sitta carolinensis

It was kind of odd, all of these, except the gull and the crow, were in a big, spread out, mixed species flock on my lawn (well, the chickadee and nuthatch were in a tree in the middle of it, but still...) centered on a great big ant nest. I've never seen anything like it before, honestly.

I almost missed the flicker; it was a juvenile, I think. There were a couple of mourning doves toddling along doing their thing and a few meters away was another pecking at the ground, but it didn't look right (barred wings and a funny bill were the only real differences at first.) It then started sticking its bill into the ground turned and gave me a good view of its chest patch and flew away showing me its white rump. I wonder how many times I've seen juvenile flickers at a distance and thought mourning dove. The similarities were much stronger than I would have expected for two birds that are so very different.
 
...Among the weird facts that are now floating around in the davefoc brain is that remex is the singular of remiges....

And on that theme... the singular of syringes is syrinx.

As to the substance of what sphenisc said:

OK, I get the idea that the secondaries are the flight feathers (remiges) which are the feathers that are attached to the ulna. But how can you tell by looking at the image in question that the secondaries, 8,9, & 10, have been replaced? If the bird, has indeed gone through at least part of one molt, does that mean it is possible to conclude the bird is at least one year old?


Looking at the near wing of the bird on the picture marked "FLIGHT"

The picture exaggerates the main features we're interested in, but it's useful for explanatory purposes.
The primaries here are the very dark flight feathers, they're numbered from bottom to top so the outermost small primary is no.1 counting up, "ascendently" to the innermost no. 10. This true for ornithologists describing the wing formula, i.e description of the primaries in terms of their relative lengths, margins and notches. Of course, for ornithologists studying moult, the numbering's done the other way. Why? because that's the way moulting generally happens - innermost to outermost for primaries.

Secondaries, the flight feathers directly above the primaries in the picture, are numbered ascendently. So secondaries 8,9 and 10 are the top 3, and show a sequential decrease in size, they're often referred to as tertials.

If we look at a real bird, then we can see on the left wing (as we look at it), the alula (a pair of small feathers in the middle of the front edge ofthe wing, then counting roung, 10 primaries, then 1-7 secondaries and a hint of the first tertial. On the right we can do the same but the tip of the 5th primary is missing. The first tertial, S8, is showing, but 9 and 10 are shorter and not visible from the underside.

This means, obviously, that I'm talking rubbish. On davefoc's bird the three new flight feathers, the dark blue adult ones, which have replaced the juvenile feathers are most likely to be secondaries 1-3. The other adult feather is a tertial, S9.

The longest primaries are visible below the secondaries and are old, juvenile ones, most of them aren't visible here.

The bird was hatched this year and it had it's first moult in the nest, the Pre-juvenile moult, exchanging its downy feathers for juvenile plumage. Having left the nest it has then started its first pre-basic moult. So we can see the bright blue adult feathers further forward on the wing, first the greater coverts lying on top of the secondaries, then a row of old, brown, juvenile median coverts, and above them, some of the lesser coverts have also been replaced.

Sorry for any confusion my comments may have caused, I hope it's a bit clearer now.
 
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http://farm4.static.flickr.com/3112/3835545822_10731b441a.jpg

I was looking at some of my holiday pictures from France and realised that this might not be what I thought it was. It was with the egrets with the black bills:

http://farm3.static.flickr.com/2544/3834760505_b044f0013f.jpg

and I thought it must be a young one. But I am not sure now

Can anyone tell me for definite?

The first is a Cattle Egret Bubulcus ibis, in breeding plumage, and the second is a Little Egret Egretta garzetta, also apparently in breeding plumage.
 
ah, thank you Kotatsu. I had recognised cattle egret in fields but for some reason I assumed that was different: largely because it was in a tree and there was more than one with a whole bunch of little egrets. Do they usually flock together? Do they (can they) interbreed?
 
I very much doubt they'd be able to interbreed, but I don't know for sure. The orange crest and chest is a sure give-away, though, regardless of the location, although these are not as pronounced in non-breeding plumage. They do mix with other egrets -- I had flocks in Japan with both Cattle, Greater, Lesser, and Intermediate -- and I believe they do form flocks on their own -- again, one of the first things I saw in Japan was great flocks of Cattle Egrets in the rice paddies. In that respect, they are very thankful birds, because if you have them in the same area, you're able to compare them easily. They also mix readily with non-egrets, such as herons and night herons, which is very convenient.

Personally, I love the egrets. There's a Lesser in a place near here now, and if I have time, I'll go and look for it tomorrow. Just as I am starting to miss the possibility of being able to see hummingbirds more or less whenever I want, I miss the egrets of Japan, and can't wait till I get back there...
 
Personally, I love the egrets. There's a Lesser in a place near here now, and if I have time, I'll go and look for it tomorrow. Just as I am starting to miss the possibility of being able to see hummingbirds more or less whenever I want, I miss the egrets of Japan, and can't wait till I get back there...

C'est la vie... personally je ne egrette rien.
 
Hello! I'm sure I have nothing significant to contribute, since I'm not a 'real' birder. ...
Welcome, Miss Kitt! I was just trying to catch up on our sightings list and noticed you hadn't got an official wellcome.

So. Welcome.

Don't worry aboutnot being a "real" birder - we welcome all and anyone, you'll find backyard birders that just like their feeders, to out and out twitchers (though none have admitted this yet).

I know you would have enjoyed Kotatsu's company, I've had the pleasure of catching up with him on the occasions he's been through London and look forward to returning the favour in Sweden (he doesn't sell his home town though!).
 

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