"To Feed or Not to Feed the Birds" is the topic of Peter Alden's speech at the Harvard Conservation Trust's upcoming annual meeting. Alden, a Concord resident, is a pioneering ecotourism guide who has scouted out and led many of the first birding and natural history tours worldwide. In recent years he has focused on biodiversity issues in eastern North America, such as the invasive plant crisis, the ups and downs of our birds, and changes in our flora and fauna.

Members and the public are cordially invited to attend on Tuesday, Nov. 27, at 7 p.m. in Volunteers Hall at the Harvard Public Library. There will be a brief business meeting before the program and the audience is invited to stay afterward for the traditional offerings of cider and gingerbread. For information go to www.HarvardConservationTrust.org.