Environment : Notes about your surroundings.

Corridors--An agreement to preserve more than 9,500 additional acres of open space in Irvine, approved Tuesday by the City Council, includes provisions for narrow “spines” of land connecting the parcels to each other and to the Cleveland National Forest and Pacific Ocean.

Wildlife will use these natural corridors to move between the open spaces, biologists say, adding that such passageways will become more vital as Southern California’s natural areas are reduced.

Under the agreement with the Irvine Co., Irvine will have more than 16,000 acres of protected open space. Among the areas protected in the latest deal is Quail Hill--along the San Diego Freeway near Sand Canyon Road--where hundreds of migrating Canada geese spend the winters.

Forest Study--Orange Coast College will offer students the chance to study Spanish and botany when it offers its first “Semester in Costa Rica” program Jan. 14-April 27. Classes will be conducted in the capital city of San Jose by Susana Salessi, OCC professor of Spanish and Italian, and John Lentanon, professor of ornamental horticulture. Students will live with a Costa Rican family; three- and four-day excursions are planned throughout the semester. Information: (714) 432-5748.

More News From OCC--Well-known British environmental scientist Norman Myers will be the school’s Visiting Scholar in Residence March 13-15. Myers has written several books, including “The Gaia Atlas of Planet Management” and “The Sinking Ark.”

Events--The Santa Ana Zoo offers Halloween activities from 6 to 8 p.m. today through Tuesday. Admission: $2. Information: (714) 953-8555.

Volunteers are needed for the annual community workday at Oak Canyon Nature Center in Anaheim Hills, 9 a.m. to 4 p.m. Saturday. Information: (714) 998-8380.

A program on ducks and shore birds will begin at 9 a.m. Saturday at the Upper Newport Bay Ecological Reserve, Eastbluff and Back Bay drives. Fee: $2. Information: (714) 640-6746.