In mid-March, whilst wintering in Brazil, Blue began spending many hours each day and night in a very urban location as shown in the GE image below - to me it looked like he may be using the trees around which the GPS locations were scattered, but I couldn't tell from GE what was so special about the few trees he seemed to have selected when there were so many others just like it to choose from?
I e-mailed the GPS locations to my colleague, Mark Prostor, to get his thoughts on what might be so attractive to the peregrine. He took a look at the locations in GE and then started looking for Panoramio images close by...he found one of the swimming pool below(and bottom left corner of the GE image above), and pointed out the GPS fixes were located at the cell phone tower that can be seen in the top right corner of the pool photo.
It also be came apparent after a few weeks that GPS locations would periodically be situated in the surrounding soy bean fields like the one below located half a mile from the cell tower.
Soy bean field