These are not store bought Bradford Pears, rather they represent a hybrid swarm that may involve crosses with pears you actually eat, or simply be Fx hybrids. Growth form is not what I expect of Bradford Pears used in landscaping. Not all the trees have thorns and fruit are all over the place in terms of size and palatability. Those characters are consistent on a given tree. I do taste them. My preference is not to get into too much plant taxonomy as not an expert, but will post pictures demonstrating variation in thorns. The trees would be climbable for a child but not a 300 lb human that otherwise climbs a lot. The branches either too brittle or too thorny. Some rival Honey Locust, which I also have a few of, in terms of unpleasantness. Chickens like to roost in those as well and they get hurt once in a while doing it as I can see. I am still going to work on killing the trees as they cause a lot more troubles than discussed in my chicken management system.
I am at lab now so will get dissecting equipment ready to look into Edgar's cause of death. Feathers will be pulled if need be to look for wounds. What I really want to see is well is what he has in his crop. It the time of year of that some birds pound down some Night Shade berries and they do get a little sick sometimes. It is also possible he over consumed on those. Whatever cause of death, it caused a rapid decline, as he was ranging yard, dodging kids and dogs while opening cans of whoop-ass on the Dominique cockerels when they got too close.