Crows and their brethren can recognize
Wearing the dangerous mask on one recent walk through campus, Dr. Marzluff said, he was scolded by 47 of the 53 crows he encountered, many more than had experienced or witnessed the initial trapping..
.. The reaction to one of the dangerous masks was “quite spectacular,” said one volunteer, Bill Pochmerski, a retired telephone company manager who lives near Snohomish, Wash. “The birds were really raucous, screaming persistently,” he said, “and it was clear they weren’t upset about something in general. They were upset with me.”