Female vs Male Red Tailed Hawk

<p>Do male or female Red Tailed Hawks have any easy identifications to distinguish one from the other? Here's a shot of a pair:<br>

http://photonatureblog.com/2012/06/17/red-tailed-hawk-pair/</p>

<p>http://www.ehow.com/how_5968694_tell-male-female-hawks-apart.html</p>

No easy way to tall male from female Red-tailed Hawks. Occasionally they will perch alongside one

another and you may be able to see one is a tiny bit larger and that would be the female. Otherwise, forget

it.

 

With the accipiters (Sharp-shinned, Cooper's, and Goshawk) and falcons, females are noticeably larger

and can often, but not always, be identified if seeing one bird by experienced birders. But also, these are

often told apart by colors also (at least with adults) which is not applicable to Red-tailed Hawks.

 

Articles (like the one above) cannot substitute for experience in the field.

<p>It is even conceivable that your pair are siblings (hard to tell from the context of your photo) and therefore could even be the same sex. While I was in Europe I watched three Kestrels trying out their new wings. Interestingly, over the two days I watched this the three stayed pretty close together, with the parents bringing prey to them.<br>

I have to admit though I'm notoriously bad about iding hawks, too much variation. I'd hate to try and speculate on their gender. </p>

<p>A general rule of thumb is the females are about 30% larger.</p>

<p>Maybe one of you can explain what I saw. I was waiting for my wife while she was shopping in Queens NYC. There was a red-tail (lots of them around NYC). When I first saw it, it was about 150 feet high circling around. It kept circling in the same area but continuously gaining altitude using the updrafts. After about ten minutes or so, it was well maybe 2000 feet high, maybe higher. Suddenly it turned east and flew straight that way. I lost track of it as it disappeared in the east.</p>

<p>I was wondering. Was it going to a feeding ground somewhere and/or moving to an area it would dive from to catch prey? Is this normal hunting or other kind of behavior?</p>

<blockquote>

<p>I was wondering. Was it going to a feeding ground somewhere and/or moving to an area it would dive from to catch prey? Is this normal hunting or other kind of behavior?</p>

</blockquote>

<p>Just about anything is possible. It could have found a better location, it could have spotted its mate, it could be a young hawk learning how to use the updrafts, etc. It certainly doesn't sound like abnormal Hawk behavior. I see them out at the Great Swamp NWR in NJ, and they'll be soaring around one moment, and the next, they've taken off in some direction.</p>

<p>After doing some research on my iBird Pro, the easiest way to tell them apart is size. It says that females can be up to 25% larger than males.</p>

<p>"A general rule of thumb is the females are about 30% larger."<br>

There's too much overlap for this to be definitive in practice, though I've banded three red-tails weighing less than 700 grams that were almost certainly male.<br>

Until DNA analysis and statistical analysis of field measurements were done by a research group in the mid-2000s, there was no way to accurately determine sex even in the hand. The analysis I mention resulted in a formula combining hallux (rear toe), culmen (the part of the bill not covered by skin), and wing chord being developed which is about 98% accurate (determined by comparing with the sex as determined by DNA). I was one of the banders providing data for the study.<br>

<a href="http://scholarworks.boisestate.edu/cgi/viewcontent.cgi?article=1010&context=bio_facpubs&sei-redir=1&referer=http%3A%2F%2Fwww.google.com%2Furl%3Fsa%3Dt%26rct%3Dj%26q%3Dsexing%2520red-tailed%2520hawks%26source%3Dweb%26cd%3D2%26ved%3D0CFwQFjAB%26url%3Dhttp%253A%252F%252Fscholarworks.boisestate.edu%252Fcgi%252Fviewcontent.cgi%253Farticle%253D1010%2526context%253Dbio_facpubs%26ei%3D7Az_T5KdK8SkrQHi5pyLCQ%26usg%3DAFQjCNHJCKcArIuSvA545cNU4_vFmANWNA#search=%22sexing%20red-tailed%20hawks%22">The study result can be found in this academic paper, which isn't difficult for a layperson to read</a><br>

More detail than people need, but it should make clear that you can not sex red-tails just by looking at them. You can't. End of story.<br>

The e-how piece linked above is decent, as observations of *behavior* can be used to sex birds in special circumstances, i.e. copulation, etc.</p>

 

<blockquote>

<p> I was wondering. Was it going to a feeding ground somewhere and/or moving to an area it would dive from to catch prey? Is this normal hunting or other kind of behavior?</p>

</blockquote>

<p>I think this is perfectly normal behavior in the sense that I've watched many RTHs do this. They catch an updraft and will ride it higher and higher. As I understand it, many young hawks will do this when they disperse and leave the family.</p>