On Sunday afternoon I received a text from Peter Bell, "Intruder at Pitt. On about 4th floor windowsill of Union. Dorothy and E2 are at top corners angrily e-chupping and diving."
I live only 10 minutes away so I hopped in the car and went over to see.
As I waited for the light at Schenley Plaza I saw a solo peregrine flying eastward over Posvar Hall. I surmised that I'd missed them and I was right. Peter was waiting on the corner to fill me in.
Returning from a weekend trip, he'd gotten off the airport bus near Pitt's Student Union and immediately heard unusual peregrine sounds. Peter looked up to see three peregrines on the building. Two angry birds had claimed the high ground. The third was in an uncomfortable spot on the 4th floor windowsill.
Peter happened to have his camera so he fired off as many shots as possible while the action unfolded. Ultimately Dorothy zoomed in and chased off the third bird (shown above). I arrived in time to see E2 bringing up the rear. Click on the photo to watch a slideshow of the action.
August seems an unusual time for an intruder but I know why she's here. Dorothy is 15 years old and has many physical challenges. In March she laid only one egg, then became egg-bound. She survived by expelling the malformed egg, then started to molt early. Three months later Dorothy still looks very ragged, a sign that she's not in good condition.
On camera at the nestbox she exhibits "tired" behavior. After 13 years of watching her, I now see her pausing in new postures as if she aches. In the slideshow the intruder looks sleek and nimble. Dorothy does not. Dorothy is challenged in more ways than one.
Under these circumstances, it's obvious to other peregrines that Dorothy is not at the top of her form. Wandering female peregrines will try their chances to win the site. Sunday's challenger flew away but she, or another, will be back. Dorothy will chase again but at some point a new female will return to the Cathedral of Learning and Dorothy will not.
This is not unusual or "terrible" activity. Chases and fights are the normal, natural way that peregrines insure strong birds own every site and produce healthy young peregrines for the future. Old humans fade away slowly, surrounded by family (or not). Old peregrines go out with a bang.
We are privileged to watch and learn.
(photos by Peter Bell)
p.s. Peter saw in his photos that the intruding female is banded. He couldn't read the band but the colors are Black/Red.