In the 60's, I was in 707 school in Miami for upgrade. The discussion one day was why we switched the window heat switches from high to low above 10,000 ft. The instructor mentioned that there weren't any birds above 10,000 ft, so the extra heat was unneeded. A classmember named Phil, a passonate bird watcher, interrupted the instructor with his dialog about the number and size of birds that routinely fly above 10,000 ft....including the eagle, giant condor, geese, vultures...his list was endless. The bird lesson rambled on while most of us went to sleep or doodled. The senior Captain in the Class, John Clower, finally interrupted Phil to relate his experience with giant birds. His comment was that he had read just the other day the NOTAM that warned to look out for a 40' crane at the end of 9L in Miami. That ended the bird watching discussion.
