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Wing Tip : Tail Tip

posted by Jerry Liguori at
on Sunday, December 29, 2013 

This is in regards to a minor aspect of raptor ID. Use wing tip to tail tip ratio on perched birds with CAUTION. It can be helpful at times of course, but is often unreliable for several reasons. Let me re-state that: it can be misleading. There are many factors that make this ID feature variable. Young buteos (especially Red-tails) have longer tails than adults (besides the natural variation in tail length of individuals), birds perch differently in trees than on power poles, or the ground, or on rocks, etc. They also lean forward in the wind, or hold their wings differently than normal when wet, tired, or ready to take off. There are other factors as well, but I'm not going to name all of them.

Anyway, never ID a buteo based on this feature solely, and NEVER EVER identify the race of a Red-tail based on this feature alone…you will be wrong as often as right, and it will have been luck if you are correct anyway!!! Besides, there are way more reliable field marks to use when telling perched birds apart. I'm not saying to never use this trait, its just the very last thing you should look at. I know wing tip to tail tip ratio has been verbalized a million times over the years, but that doesn't mean you shouldn't question it. In fact, question everything you hear or read when it comes to bird ID, because I can tell you with certainty that there are a ton of errors in the literature, and inaccuracies perpetuated out loud by the every-day birder. I tell people all the time, regardless of what I say about raptors, research it for yourself to really understand it or see if its true.

Check out these birds just to note their posture and where the wing tips fall in relation to the tail tip. Especially on the first 3 birds, which are Red-tailed Hawks


 Red-tailed Hawk
 Red-tailed Hawk
 Red-tailed Hawk
Rough-legged Hawk
Ferruginous Hawk
 Northern Harrier
 Prairie Falcon
Red-shouldered Hawk

Goshawk Refresher

posted by Jerry Liguori at
on Friday, December 27, 2013 

My original post on this subject had lots of nice color photos of Goshawks, and the B&W composite below, and I thought to myself -- why am I showing these color photos when the composite is the only thing I want to show? Goshawks are easy to identify in pictures showing all the field marks, but in the field with less than ideal views…maybe not so easy? Knowing how to identify Goshawks in flight is absolutely a matter of experience, there is no trick -- the more you see and study, the more familiar you become with them! But knowing the key ID traits helps speed the learning process.

The absolute #1 thing to look for is the shape of the wings. Goshawks have broad wings that taper toward the tips, and in some poses look like "broad-winged falcons", but in a soar show a nice angle where the base of the wings meet the hands. The tail is always long giving it that classic accipiter look! Adults are shorter-tailed but still look like the classic accipiter in most poses. The other trait that is important is the way they flap. Goshawks can flap their wings confusingly quickly (often smaller males), or labored and somewhat slowly (often larger females), but the wing beats are not snappy and weak (like Sharpy) or stiff (like Cooper's), but "fluid". I'm not going to say tail shape is useless, but it is far less helpful when separating them from Cooper's Hawks. Both can appear as "broad-tailed" as the other, but Goshawks vary more in regards to tail tip shape (rounded, squared, or wedged). Goshawks often appear slightly smaller-headed than large Cooper's Hawks, but male Cooper's Hawks after look tiny-headed.

Anyway, wing shape and wing beat are the keys to Goshawk ID in flight with less than ideal views! And here's a color photo of the juvenile plumage for those who want to file it.

Exquisite Harlan's Red-tail!

posted by Jerry Liguori at
on Sunday, December 22, 2013 

Brian Sullivan passed these photos on to me of a bird found by John Mueller and photographed by Robert McMorran thinking I'd like to see them….and all I have to say is "WOW."

Check out this gorgeous juvenile Harlan's Red-tail that Robert photographed
(click photos to enlarge). The topside plumage is intricate, just a great looking bird and an excellent example of another variation in the endless variation of Red-tailed Hawks! I have seen a few with heavily "spangled" topsides (below) but none with quite so much as this. Anyway, thought I'd share it with Robert's permission, thanks Robert!

"Eye spots" on hawks

posted by Jerry Liguori at
on Friday, December 20, 2013 

Certain birds are known to have "eye-spots" on the back of their head, especially a few species of hawk and owl. I've heard several reasons why some birds have them, but would like to hear what others think about their function or purpose?

And, don't identify hawks by this trait alone…several of them can show it. It was believed years ago that it was a good trait for perched Rough-legged Hawks (below), but I have seen too many Red-tails (below) and a few other buteos show this. These are just a few examples, including this male Harrier (below) with a neat pattern they typically show. THESE SINGLE SPOTS ON SOME HAWKS REALLY DON'T RESEMBLE EYES, but just wanted to make a point.

 Rough-legged Hawk

 Red-tailed Hawk

 Northern Harrier

Raptor Tail Patterns

posted by Jerry Liguori at
on Monday, December 16, 2013 

One thing to be careful of, or take note of (especially if you are a bird bander), is how certain patterns may look odd on a bird's tail but are actually the norm. For instance, Harriers often have darker or less marked central tail feathers compared to the rest of the tail. A male Kestrel's outer tail feathers (and often the last several outers) are banded, while the rest of the tail is not. Adult Goshawks have muted bands on the tail but often the central feathers are even more muted, or some have outer tail feathers that differ from the rest.

There are other examples in the raptor world, but these are just a few, check out the pics below to see some examples ("click" to enlarge). I commented previously on the difference in the outer tail feathers of adult Broad-winged Hawk: http://jerryliguori.blogspot.com/2013/07/broad-winged-hawk-tidbit.html


 Juvenile Northern Harrier
 Adult Male American Kestrel
 Juvenile Male American Kestrel
 Adult Northern Goshawk
 Adult Northern Goshawk
Adult male Northern Harrier

Winter Harriers

posted by Jerry Liguori at
on Sunday, December 15, 2013 

Had a fun day today...only saw a few raptors, which was surprising. But they were fighting over a duck carcass (not sure which bird took it down) and I got to photograph them from inside my car. They ignored me for the most part as I just rested my lens on the car door and shot away. Its rare when this happens, and the photo opportunities are ideal, I was lucky to be in the right place at the right time. I have lots of "keepers" from today and too many pics to go through tonight, but here are some Harrier shots and a Rough-legged Hawk (top photo, "click" to enlarge). Also saw a few Harlan's, a bunch of other Red-tails, Kestrels, and Bald Eagles.

Videos

posted by Jerry Liguori at
on Saturday, December 14, 2013 

Got my VIDEO page up and running and hope to update it every day if time permits. Anyone interested, the link is below...feel free to bookmark it.

http://www.jerryliguori.com/videos

video


Goshawk tip

posted by Jerry Liguori at
on Friday, December 13, 2013 

One trait (that is unpublished) I don't mention often is the faint "commas" along the base of the outer primaries that many juvenile and some adult Goshawks show. The are not nearly as visible as the "commas" on Red-shouldered Hawks, and difficult to see in the field, so there are much better traits to rely on to identify Goshawks. But, with the innumerable images on line these days, it may come in handy for confirming the ID of some photos. Check out the pale area along the primaries on these Goshawks; Cooper's and Sharpies lack this, but I won't say ALL lack this because I know never to say "always", "never", "all", or "none" when it comes to raptor ID!

Juvenile Harrier eyes

posted by Jerry Liguori at
on Wednesday, December 11, 2013 

In regards to Harrier eye color and plumages, I was asked about juveniles, so I thought I'd put up some pics to show the differences. First of all, it has been proposed or talked about for years that juvenile males and females have a slight difference in plumage, but for the most part this is not true. The plumages overlap greatly; there might be a slight difference on average, but it is unreliable to sex juveniles based on body plumage alone. I won't even say what those differences could be, because it would be misleading more than helpful to the birding community, and too often I hear field marks perpetuated that are absolutely false (another post I should write). Here is a link to the post I am referring: 

http://jerryliguori.blogspot.com/2013/10/juvenile-harrier-color.html

Anyway, juvenile males have yellowish eyes, and juvenile females have brown eyes. Sometimes, juvenile males show a bluish-yellow eye, or even brownish-yellow. Hawk banders know this stuff. Here are some examples below that will help you identify photos of juveniles, of course, noting eye color in the field can be extremely difficult. And remember, fairly streaked juvenile males with yellow eyes can be confused for adult females, so check your photos!
  Juvenile Female
Juvenile Female
  Juvenile Male
  Juvenile Male

Subscribing to my Blog

posted by Jerry Liguori at
on Tuesday, December 10, 2013 

Just to let anyone know who may be interested in subscribing to my blog, check out the link below, it should be helpful. And a second (possibly easier way) link as well for gmail users. I also tweet my new posts @ twitter.com/JerryLiguori

How to Subscribe to or Read ATOM and RSS Site Feeds

https://support.google.com/blogger/answer/99761

Harrier Eye Color

posted by Jerry Liguori at
on Monday, December 9, 2013 

Someone asked me if adult female Northern Harriers have a plumage that coincides with their eye color. In other words, do yellow-eyed adults look different than darker-eyed adults? And the short answer is no, adult females can look rufous washed underneath, buffy washed, heavily streaked, or lightly streaked, at any age of their adulthood (or with any eye color), below is a few examples ("click" on images to enlarge). 

And, it takes a few years for females to get the lemon-yellow eye that adult males have. Is it possible that a certain plumage is more common than another -- of course, but that is irrelevant to this issue. Thanks for the questions and hope I can answer them as they come…
 Light brown eye, buffy body
 Dark brown eye, buffy body
 Yellow eye, orange-buffy body
 Pale brown eye, buffy body
 Dark brown eye, buffy body
 Brown eye, buffy-orange body
 Pale brown eye, buffy body
 Pale brown eye, buffy-orange body
 Yellow eye, buffy body
 Dark yellow eye, buffy-orange body
 Pale brown eye, buffy body
Yellow eye, orangey body
 
 Yellow eye, orangey body
 Yellow eye, orangey body




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