Gene Mancini, the hawks' guardian angel at the Franklin Institute, has been finding these rather nasty objects on the top ledge where the hawks perch quite often these days. We have also learned that these pellets are being found on the roof of the Free Library.This one was still very moist when he found it, and he checked in with John Blakeman as to its significance.
"Very significant. Collect and save every one of these you can find. These are "pellets," in formal ornithological parlance, called "castings" by falconers. These are the undigested remains of yesterday's food, and accurately reveal what the hawks ate the day before.
And that's always a great question. What are the hawks eating in that particular area. The pellets or castings will reveal this. We so infrequently are able to find these things. After one rain they will fall apart and never be seen.
These are essentially sterile, non-toxic. The digestive enzymes have really taken out all the bad stuff. This came up through the mouth, not out the anus. Nothing fecal about this.
Again, collect all of these you can. What urban red-tails eat is still a big question. And mark down the collection date. Food and prey will change as the birds mature and the seasons and prey change.
No need to refrigerate. Just keep them dry. A paper bag works well. Don't put them in a sealed plastic bag until they are completely dry.