“It blows your mind. Thousands of them. They just keep rolling in.”  It’s a spectacular display of sight and sound, a massive swarm of as many as 20,000 crows, a sky blotted black by their numbers, a crescendo of cawing that slowly fades to an eerie silence, night closing in. As it has for at least 30 years, this flock of mostly American crows arrives in Lawrence, Mass. in November, and carries out some of the primordial behaviors that still puzzle the amateur birders and professional ornithologists who study what many of them believe are the world’s most clever and … Continue reading →