Posted by Jim Hackley on October 25, 2011 at 1:29 AM
During the summer we had several juvenile Cooper's Hawks visit the water trays we leave out in the back desert. I thought I would share another hawk encounter with some interesting behavior. One afternoon I stepped out to photograph a Cooper's Hawk standing in a water tray and was able to only take two pictures when he was suddenly driven off by another larger juvenile Cooper's. The second larger juvenile landed right next to the water tray, started squawking and promptly took the place of the first hawk it had driven off. The second juvenile stayed in the water tray for several minutes when all of a sudden it looked up and started to flare and puff up. At that time a third large juvenile landed about 5 feet from the water tray, spread his tail feathers, puffed up and slowly approached the water tray driving off the second hawk. This third hawk seemed to be the largest of the three and ended up staying in the water tray for several minutes drinking and splashing around.
It was interesting see the hawks react to one another but I was surprised to see that the younger juveniles (2nd and 3rd hawks) were bigger that the first Cooper's with the orange chest plumage (but still with yellow eyes). Any idea on the age of these Cooper's Hawks?
Regards,
Jim
Posted by Jim Hackley on October 25, 2011 at 1:30 AM
Second juvenile Cooper's still squawking after drving away the first hawk above.
Posted by Jim Hackley on October 25, 2011 at 1:31 AM
The second Cooper's reacting to the third Cooper's which has just landed five feet away.
Posted by Jim Hackley on October 25, 2011 at 1:32 AM
The third Cooper's Hawk spreading out tail feathers and puffing up to drive the second hawk away.
Posted by Jim Hackley on October 25, 2011 at 1:33 AM
The third Cooper's making his way over to water tray after second hawk has gone.
Posted by Jim Hackley on October 25, 2011 at 1:35 AM
Don't know the ages, but they may simply be starting to show the size-difference between males and females. The three might even be siblings from this year.
Very nice images, and interesting behaviour!
Sandy
Posted by Brian Gatlin on October 25, 2011 at 8:55 AM
neat encounter, Jim. what month were these taken? the top bird appears to be a 2nd calendar year bird (perhaps the same one you've been watching and photographing for a while now?)--it has nearly completed it's first prebasic molt into adult plumage but retains a few brown juvenile feathers (visible in the back and wing, as well as that lower tail feather) and the eye has turned orange but not red yet. The other two are 1st calendar year juveniles with nice fresh plumage.
The size difference, as Sandy suggests, almost certainly pertains more to sex than to age--females are noticeably larger than males (and of course there is also some variation within the sexes, but the smallest females are still bigger than the largest males).
Posted by Jim Hackley on October 25, 2011 at 10:31 AM
Thanks Sandy and Brian, I did not know about the size difference. This encounter was on August 24th all within an 8 minute span.
Posted by Joseph Jupin on October 27, 2011 at 10:48 AM
Your photos are quite beautiful. Thank you for sharing them.
Discussion
9 repliesIt was interesting see the hawks react to one another but I was surprised to see that the younger juveniles (2nd and 3rd hawks) were bigger that the first Cooper's with the orange chest plumage (but still with yellow eyes). Any idea on the age of these Cooper's Hawks?
Regards,
Jim
Very nice images, and interesting behaviour!
Sandy
The size difference, as Sandy suggests, almost certainly pertains more to sex than to age--females are noticeably larger than males (and of course there is also some variation within the sexes, but the smallest females are still bigger than the largest males).