By Dugan Arnett Globe Staff,Updated February 17, 2020, 3:27 p.m.
LAWRENCE — They arrive, every evening, by the thousands, descending upon a quiet stretch of riverbank near a noisy highway overpass.
Crows resting on tree branches. Crows circling high above the Merrimack River. Crows relieving themselves on the footpaths near the water.
It is like something Alfred Hitchcock would’ve dreamed up, some residents say, except that it is real and — as those who have stumbled upon the birds’ bizarre nightly roosting ritual can attest — somehow even stranger than it sounds.
“You can’t explain it,” says Craig Gibson, a Catholic chaplain at Lawrence General Hospital and regular observer of the crows’ behavior. “You just gotta see it.”