The plumage of the Red-tailed Hawk has lots of variation. Even if your someone who loves to study hawks, you may want to pull your hair out if looking at a bird that doesn’t fit the range of variation you know to occur for a specific race of Red-tail. But this variation can be a good thing, it is invaluable when you want to confirm that an individual bird is the same one you are seeing day to day or year to year.
When trying to ID an individual bird on separate occasions, you need to consider several things. You can’t rely on one characteristic, some birds may show a distinct trait, but many will not. I use a form sheet I made up with a space at the top for a name I give each bird and the date photographed (categories below). The form just helps me keep things straight, so I don’t overlook anything. An example of the form is shown below. The form helped me prove that a pair of breeding birds that occupied a specific territory in summer weren't the same birds occupying that exact location in winter, as another local birder suggested. We know that some Red-tails remain on territory year-round, while some migrate south and are replaced by other Red-tails. Noting distinct plumage traits has also helped me verify when instances like this occur; and that a certain Red-tail has come back to the same patch every winter since 2004 -- check out the pictures below of one individual (all photos by Derek Lyon).
2004
2005
2007
2010
2013
"Click" to enlarge form
16 Comments:
Thats pretty neat Derek. I like your idea for having a spreadsheet for traits.
It is fascinating that birds winter in the same areas from year to year. Great post.
Thanks for your comments Bryce ... there have been several over the year, but this bird has been around the longest.
I forgot to mention that when I started doing this I wasn't sure if Red-tails retain the same pattern in their plumage after feathers are replaced by molt. So I made sure to pick some feature I knew wouldn't change, like the feet, shape of the eye ridge, or in this case a band on the leg. The result, as you can see, is that they do retain the same pattern year after year.
It will be interesting to see if the tail pattern changes even a little bit over time...
Hey, look, a "standard" plumaged red tail! :) Very nice.
I see a dark center streak on the white throat that seems consistent in most of the photos, unless it's a shade or shadow of some sorts.
Any info on when and where it was banded?
I enjoyed this article. I have participated in a volunteer raptor nest survey for the local parks in NE Ohio the past four years. I have watched a number of red-tailed hawk nests. I have often wondered if they are the same birds I see in the winter in the same areas when I am out hiking and looking for old nests in the leafless trees. I am pretty sure that one pair of adult hawks I saw a couple of years ago were year-round residents. They were perched close together in a large tree near a nest during a snowstorm in February. (I am not sure how tolerant red-tails are to each other.)
I was wondering if raptor banders have ever considered using thin colored bands above and below a metal band. Or, maybe adding thin lines of color on the metal itself. I have seen that other birds that are banded have colored bands - most notably some shorebirds and some gray jays (in Algonquin PP). It can't be that expensive to add a thin line of color to a metal band. I was thinking it would make ID at a distance a lot easier.
Ken Andrews
NE Ohio
Jerry:
The bird was an adult when first encountered; I don't really expect any change (though I'm always looking).
Hatem:
I haven't been able to get anywhere near this bird (it's very wary of people) so, no info from the band. I've been trying to get a good photo of the band, but the 2013 photo is the closest I've ever gotten. Most of these northern RTs don't really know what people are, so they're usually tou get close and are tame. This bird must have been traumatized during the banding to be as wary as it is.
Sorry Ken, I'm not a bander, so I can't address colored bands. However, I did come across a bird with a colored band once. It even had a big number 35 on it and was very visible. I think it was part of a private study since there was nothing else on the band. So it has been done.
Thanks for the answer, Derek. I can tell you from my experience as a volunteer bander for many years, that the process (for the most part) is not traumatic at all. Quick example - a few years ago, we caught a juvy RT that came in on a pigeon lure and was trapped in the bow net and we did our thing (the whole time had its hackles up, mouth wide open and very defiant) and then we released it. It flew up onto one of the perch poles surrounding the banding station and stayed there until it decided to come back again and get the same pigeon only to miss and end up tangled in the miss-net. We untangled her and let her go and she repeated the same process 2 more times before finally deciding it wasn't going to work. This is another great part of this research is that clearly tells you this bird was completely unaffected by the banding process and was only focused on hunting. She was also very healthy and no signs of emaciation or such. Just very hungry. Typically, RT's are very defiant and some times end up hanging around after being released. Most, though, are gone once released and show typical behavior of wanting nothing to do with you. Accipiters on the other hand are far more stressed and high-strung and never want nothing to do with you once let go. Falcons even more relaxed than most. So I would probably say, unless the individual banding this particular bird was really bad and abusive, it probably is just a normally skittish bird which is another probable reason for why it has survived 9 years and we've had the luxury to see you monitor a vital portion of it's migrating path within that time frame. This is terrific information if you look at the years since you've been documenting her. The first one in 2004 and she's already a beautiful and healthy adult and is in the same condition almost 9 years later. So we know that bird is at least 10 years old. Absolutely terrific!
Ken, a simple answer is that the band needs to be able to out-live the bird itself and the general purpose (at the time this was thought of) is to have it made out a material that is lightweight yet durable enough to outlast the bird itself. The only times that the band is viewed as serviceable is when the bird is caught and one can record the information on the band or if and when the bird dies and someone finds it and reports the information. ID'ing the bird is separate from this particular, designated purpose of research and why you don't see any colors or other things that would help with identification in this particular case.
I believe a color band is only useful when researching a certain group of individuals at a certain location for a short period of time to distinguish them from one another. Despite how scarce they are, you would quickly run out of options if you were to tag raptors (of any family) that migrate such large distances and overlap territories etc.
To add to what Hatem said, most (if not all) banding of raptors is done at migration sites and records where a bird was banded and not where it was born, it also record the birds weight and physical dimensions.
If Jerry doesn't mind, keep us posted on this beauty, Derek. May she live to be 40! :)
I don't mind at all Hatem, hope to get updates Derek.
Thank you for the replies. I do appreciate that you shared information and your experiences. It must be great to get to see these birds up close and help gather information on them to help them.
Ken
Last winter I photographed a banded Ferrug and when she flew off I noticed she had a telemetry setup on her back too. I was able to get in touch with a researcher who was able to make an probable ID on the bird (not all numbers of the band could be seen) and sent me photos of her as hatchling, when banded. I guess the telemetry setup was no longer functional, so it also provided a sighting report for their research too!
I have only lived in this area for one winter, but have been looking at the Harlan's this winter to try and see if they are the same birds I saw in the same areas as last winter Since their markings are quite distinct, but so far most are not the same (one possibly the same).
Thanks for sharing about this bird!
Yeah it's tough reading the numbered color band. Most of the time you gotta have a high powered scope and the bird has to be at a decent distance and the leg well exposed, but it is doable. Most of the 'city nesting peregrines' are getting them these days.
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