Notes about your surroundings.

Marsh News--A volunteer work session sponsored by the UC Irvine Cooperative Outdoor Program will be held at the San Joaquin Freshwater Marsh Reserve on Saturday. It will be from 1 p.m. to sunset.

The work session will involve light maintenance work, including chopping cattails, repairing dikes and cleaning clogged drains. Participants should wear work clothes and be prepared to get wet.

Those who would like to volunteer are asked to meet at the UC Irvine Arboretum on the university’s North Campus.

Also, the program is seeking individuals or groups willing to help with ongoing habitat enhancement and restoration work. Special arrangements can be made for clubs and other service organizations. For more information, call marsh steward Bill Bretz at (714) 856-6031.

Bay Tours--The Friends of Upper Newport Bay will offer free guided tours of the Back Bay area beginning at 9 a.m. Saturday. The last tour will depart at 10:15 a.m.

Tour participants will be able to watch the thousands of migrating birds that have descended on the area for the winter months. The birds include terns, gulls, dowitchers, plovers, rails, willets and sandpipers.

Those who would like to participate are asked to meet at Backbay and Eastbluff drives in Newport Beach. For more information, call (714) 646-8009.

Open House--Sycamore Hills, a preserve owned by the city of Laguna Beach, will host an open house Saturday.

A nature trail winds past the preserve’s groves of native sycamores, stands of oaks and coastal sage scrub.

The entrance is on the east side of Laguna Canyon Road, less than one mile north of El Toro Road. The open house will begin at 10 a.m. and continue until 4 p.m.