[texbirds] Mystery bird - correct ID and how to get it

From: MBB22222@xxxxxxx
To: texbirds@xxxxxxxxxxxxx
Date: Fri, 29 Mar 2013 19:52:04 -0400 (EDT)
"The most beautiful experience we can have is the mysterious. It is the  
fundamental emotion which stands at the cradle of true art and true science.  
Whoever does not know it and can no longer wonder, no longer marvel, is as 
good  as dead, and his eyes are dimmed." - Albert Einstein
 
Because I have a lot of visitors but only a few who would make a loud guess 
 (so far those who made suggestion are all wrong) I decided to post the 
answer  sooner then I planned. Sorry, I thought that this quiz is going to be 
much  easier but it in fact it is not. But why it turned out that there are 
no correct  answers. Well, it seems that most people might do not know what 
this is all  about.
 
Itâs all about love. Wait, no, no, itâs all about molt. Or better said  
birdâs age and molt stage in given part of the year (end of March in our 
case).  What knowledge about call notes can do to help in identification of 
songbirds,  molt knowledge can do in many other birds, btw songbirds included. 
And knowing  molt sequences in terns can really help to identifying those 
birds. Perhaps this  mystery bird (of course this is a tern) is an excellent 
example. Evidently it  thrown out from a right track mind of many people making 
them going into a  totally wrong direction. Dark wings and back became the 
traits to follow leading  to completely wrong answers and discourage others 
to risk answering. If I posted  recording of a singing bird I bet I will 
have plenty emails, presumably most, if  not all, with correct ID. Also, 
sometimes, I keep forgetting that I do have a  luxury to work only with very 
few 
species so I can paid attention to many  details. Person who have interest in 
several hundreds or even thousands usually  use field marks found in field 
guides and those can be sometimes misleading or  ever in some very rare 
cases pure wrong. 
 
For some reason (I think dark wings and back) two species of terns were  
suggested several times: Sooty and Black. Both these species have dark or 
black  rump so by only this trait alone they should be excluded at the very 
beginning.  Practically all people were right in one thing - it is a tern. So 
what next.  There is one simple way that if used from very beginning will left 
only one tern  species on the table. Age and  molt stage. It is a second 
calendar year -  look at the even wear of all primaries and secondaries and no 
sign of any  primary or secondary molt limits. There is only one tern in 
Texas that fits into  this scenario in March..
 
2nd calendar year (March) Forsterâs Tern. 
 
With no preformative molt (never was confirmed that FOTE has one) its  
prealternate molt can start in  August (during his first calendar year) but  it 
is a partial-incomplete molt that only includes head and back feathers,  
occasionally 1-2 tertials and, sometimes, 1-8 tail feathers. Its next prebasic  
molt (PB2) starts between March and May. So we have a perfect match.
 
Now Black Tern, it will be in the middle of complete preformative molt so  
growing or shedding feathers and molt limit will be visible. Same in older 
birds  as they will be about to complete or just complete prebasic molt and 
already be  in the middle of prealternate primary molt.
 
Sooty Tern will be in similar situation - in the middle of complete  
preformative primary molt
 
I have couple of other terns mentioned.
 
Common Tern; it will be either in the middle of preformative molt and older 
 birds completing right now prebasic and prealternate primary molts so molt 
 limits will be perfectly visible.
 
Sandwich Tern; in middle of preformative molt and even might have molted  
innermost primaries as part of prealternate molt as well. Older birds will 
show  molt limits too.
 
So as you can see we can eliminate all other terns in Texas in very easy  
way. Forsterâs Tern juveniles retain juvenal primaries and secondaries (and 
many  other feathers as well) for long time so those became dark. In some 
light  conditions and depend of light angle they might even appear darker.  So 
now  is time to show you the same bird in other frames so nobody has any 
doubts left  to the correct ID.
 
Showing his banditâs mask that gives his ID right away.
 
_http://www.pbase.com/mbb/image/149426310_ 
(http://www.pbase.com/mbb/image/149426310) 
 
And here just one more to show that at this stage they can sport quite  
distinctive dark carpal bar that also can lead to even further confusion in the 
 field when sometimes its head pattern might be judged wrongly from far 
distance  to have a dark cap and then IDed wrongly as a COTE. Noticing either 
exact head  pattern or molt stage, or even better both, can prevent this 
misidentification. 
 
_http://www.pbase.com/mbb/image/149426312_ 
(http://www.pbase.com/mbb/image/149426312) 
 
Now somebody (especially beginner) will ask: where I can learn all of this; 
 searching internet will take me hours if not days and results will be poor 
on  none. Fortunately there is a one special guide that not too many people 
own but  some call it a bible. Peter Pyle published this two-volume book: 
 
Identification Guide to North American Birds, Part I: Columbidae to  
Ploceidae
See more info here: _http://www.pbase.com/mbb/image/149421439_ 
(http://www.pbase.com/mbb/image/149421439) 
 
And
Identification Guide to North American Birds. Part II: Anatidae to  Alcidae
See here: _http://www.pbase.com/mbb/image/149421486_ 
(http://www.pbase.com/mbb/image/149421486) 
 
Terns are included in volume II.
 
If anybody think seriously about studying birds this book is not only a  
bible but a must. It will not replace other popular bird guides (it has no 
color  illustrations, etc) but will provide you with gold mime of information 
and other  data you wonât find in any other popular guides. Having both, good 
field  guide(s) and Pyleâs book(s) is all what you need to have a lot of 
fun and do  some serious learning at the same time. Molting process in birds 
is a  fascinating subject to study.
 
Last thing - one person suggested to me that posting one photo like that  
makes more bad than good for the beginners. If more people think this is true 
 please let me know and might never do it again if I find arguments to be  
convincing. At this moment I think that I am just trying to show that there 
are  other ways to ID birds, ways that can be very productive even in case 
with one  photo available; photo that is illustrating only incomplete bird 
body  parts  and showing some other confusing traits. I am trying to explain 
what  more is possible to look at in the field that popular guides say not 
much about  it. Let see what others might to say about this. Especially the  
beginners.   . 
 
Mark B Bartosik
Houston, Texas
_http://www.pbase.com/mbb/from_the_field_ 
(http://www.pbase.com/mbb/from_the_field) 
 
 
 
 
 


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[texbirds] Mystery bird - correct ID and how to get it

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