V good choice. I nearly went a couple of springs ago! My target apart from general steppe and wetland birding would have been Lanner.
http://www.birdingitaly.net/pugliaeng.htm
In late April, I think a trend for harriers including Pallid to enter Italy via Tunisia and Sicily, then cross to east and exit over Adriatic from points up this coast.
If you get bored (ha ha) then would recommend a day trip down to Matera in Basilicata. Amazing scenery and 1000+ pairs of Lesser Kestel in the old town on the cliff face.