The flow of migrating hawks was slowing down after a day of record numbers. The local Red-tailed Hawks were returning to the skies around Mt Philo. An eagle was gliding by minding its own business heading south when one of the local Red-tails decided to escort it out of its territory.
Things were getting back to normal. I noticed the juvenile Red-tails playfully chasing each other around after what must have seemed like a never ending parade of hawks flying in their home airspace. 
One of the reasons for going to Mt Philo was that I wanted to photograph the local Red-tailed Hawks so that I might be able to tell a juvenile from adult and, for that matter, to be able to differentiate male and female in the adults. Check out this female below; she must have just finished gorging herself. Look at the size of the crop ( just passed the dark brown head feathers -large white bulge). Must have been a big lunch!
I was clicking off some images when I noticed the two juveniles turning and diving in a very steep dive down below the tree tops then zooming back up playing tag. 
I tried to follow them as they continued to to play and just kept firing off images as fast as the camera would go. 
I saw one roll up on its side to deflect the charge of the other and wondered if I could capture that. I continued to follow them hoping one of them would roll on its side again. All of a sudden one rolled up. Then the other went into a steep dive and it was over. They were out of sight. It was over before I knew it! I watched them fly around chasing each other but that was it. They didn't roll on their sides again. 
All the way home I wondered if I had gotten them on their sides. Well, when I first looked at the images on the computer, I just couldn't believe what I had on the screen in front of me! Both of the juvenile Red-tails were flying upside down! I was amazed! This image was captured just before they were upside down. You can see the lead bird setting up for this.
These images ( numbers 4226 through 4229 ) have been cropped so you can better see what the Red-tailed Hawks were doing. The images show the sequence as it happened.
I never saw this while I was shooting the camera, in part because of the mirror. It flips up to record the image and temporally blocks what you can see in the view finder. The camera can record 6 1/2 frames a second and I only got four images- that's how fast it happened. The images didn't come out clear and sharp, but are good enough to show them upside down going into a dive. I hope to return this coming week to watch and photograph the local Red-tails flying around Mt Philo .Please email me off list if you can shed some light on this flight behavior.
Thanks!
Peter Manship
images and story © 2009 Peter Manship all rights reserved
With the sun in my eyes I thought Rough-legged Hawk hover-hunting. The hawk then flew over to a snag right next to the road. 
I got this image and realized that this hawk could be a Red-tailed Hawk which also hover-hunts sometimes. The difference is the height the red-tailed was at , about a third of the distance closer to the ground then a Rough-legged Hawk would hover-hunt at. From this new angle I could see the tail banding and the what I call spangled breast feathers of the Red-tail as apposed to the dark more solid belly and single dark tail band of the Rough-legged hawk. So if I hadn't tried to get a photo of this bird on the snag I would have ID-ed this bird as a Rough-legged hawk an been 100% wrong . Which is one of the many reasons that I love birding, your always learning something new about the birds your watching... This last image I got driving home on rt103 in Rockingham Vt, the hawk was gliding along in big circles which allowed me to get a good image.