Mass Audubon is leading these bird walks:

• December 3, 8AM-9:30AM:  Winter Bird Walks: Residents and Guests, at Magazine Beach Park Nature Center (668 Memorial Drive, Cambridge) for ages 14+. Free. Registration is required.
• December 11, 9AM-12PM: Teen Birders: Wintering Birds, at Fresh Pond (Cambridge) for ages 13-17. $38 members ($46 nonmembers). Registration is required.