I received word today that a dead hawk was found on 4th Ave and 9th Street. It appears to be a juvenile. You can see a photo here.
I don't know for sure, but it seems likely this hawk is either from Washington Square Park or the Avenue A nest. The body has been sent away for a necropsy to determine the cause of death, but my first guess would be that it hit a window.
Roger Paw, who keeps track of the Washington Square Park hawks, has also posted the news here.
This follows the tragic loss of one of the Cornell hawk fledglings earlier in the month. You can read the details here under the news for July 8. The fledgling was chasing a squirrel when it flew into a window. Sadly, this is a common danger for all birds. In December 2013, a juvenile hawk slammed into a glass bus stop on Avenue A and, fortunately, survived.
I've not seen all three Avenue A hawk kids together for about three weeks. As they learn to hunt, it becomes increasingly difficult to keep track of them. They are still clumsy and learning to fly, hunt, and take care of themselves. If you see one in distress, please send me a note or contact WINORR (Wildlife in Need of Rescue and Rehabilitation). They can assess the situation advise on how to proceed.