CHICAGO — Bird migration is on the rise, and so are window collisions. As temperatures slowly drop in Chicago, 300 millions to 400 million birds are crossing the continent heading south to their nesting grounds for the winter, according to Annette Prince, director and president of Chicago Bird Collision Monitors, a nonprofit dedicated to the respite and protection of migratory birds through daily rescue efforts. It’s been a busy few weeks for the organization, Prince said. Volunteers at the nonprofit pick up more than 100 birds a day. Most early mornings, she said, a team of a dozen volunteers...