Notes about your surroundings.

Open House--San Mateo Campgrounds will be the site of an open house Saturday sponsored by the California Parks and Recreation Department, in conjunction with South Coast Audubon and the Pendleton Coast Natural History Assn.

The campgrounds are in an unincorporated area in northern San Diego County, just across the Orange County line.

The schedule of activities include:

* 7:30 a.m.--Bird walk.

* 9 a.m.--Bird walk for children ages 7 to 12.

* 10 a.m.--Junior ranger program.

* 5 p.m.--Bird walk.

* Dusk (about 8 p.m.)--”Range of Light” slide show.

There will be refreshments served throughout the day and a campfire will be held in the evening.

To reach the campgrounds, take Interstate 5 to Cristianitos Road, turn left over the freeway. San Mateo is about one mile up from the freeway, on the right side of the road.

For more information, call (714) 492-0802 or (714) 830-7806.

Star Party--An evening of stargazing hosted by Featherly Regional Park will be held Saturday. The event begins at 7 p.m. It is free, but there is a $2 fee for parking.

The park is at 24001 Santa Ana Canyon Road, Anaheim, north of the Gypsum Canyon Road exit off the Riverside Freeway.

For more information, call (714) 637-0210.