When animals disappear
Five places in the Bay Area to see endangered species

1. San Bruno Mountain Massive antennae dot the summit, and dense clusters of Daly City and Brisbane subdivisions creep up the base, but the rising bulk of San Bruno Mountain is still ranked among Madagascar, Borneo, and the forests of Tanzania as one of the world's foremost biodiversity hot spots. Along the looping Old Guadalupe and Summit trails, lucky hikers may catch a glimpse of the endangered Mission blue, callippe silverspot, and San Bruno elfin butterflies fluttering among the rare wildflowers and endemic manzanitas. Main entrance Guadalupe Canyon Blvd. near Bayshore Blvd. To help preserve this threatened habitat, contact San Bruno Mountain Watch at (415) 467-6631 or www.mountainwatch.org.

2. Alameda National Wildlife Refuge Runways, munitions bunkers, and electrified fences characterize the terrain of this former naval air base that's also a popular spot along the Pacific flyway for many rare and endangered birds. California least terns nest seasonally in the rich, wetland vegetation along the bay; brown pelicans roost on the rocky breakwater; and golden eagles and peregrine falcons soar the skies, searching the barren asphalt fields for prey. The price of admission to this thriving, postindustrial ecosystem is assistance in removing nonnative plants and debris. Because the park isn't open to the public yet, visitors must accompany Friends of Alameda Wildlife Refuge on one of its biweekly reclamation missions. Contact FAWR through the Golden Gate Audubon Society at (510) 843-2222 or go to www.fawr.org.

3. Garin Regional Park The creek-fed ponds and rugged arroyos of this Hayward park are some of the last remaining habitats of several endangered species. Alameda whip snakes slither through prickly patches of chaparral, and red-legged frogs hunt for insects along muddy banks. Maintained by the East Bay Regional Park District, the site has a visitor center and hiking and horseback trails, and it's accessible by public transportation. 1320 Garin, Hayward. (510) 562-PARK.

4. Round Valley Regional Preserve A few antique pieces of farm equipment remain scattered among the ryegrass, wild oats, and ripgut brome, but nature is doing its best to erase any evidence that this rugged terrain northeast of Walnut Creek, also maintained by the EBRPD, was once a ranch. Although trails cut through the black sage and chamise, a slew of creatures such as the endangered kit fox, California tiger salamander, and western pond turtle (as well as golden eagles and burrowing owls) are reclaiming the park's hills as their own. Marsh Creek Road, near Clayton (see EBRPD Web site for directions). (925) 757-2620, www.ebparks.org/parks/round.htm.

5. San Francisco Zoo For nature lovers lacking the patience and stealth often necessary to witness a rare creature in its natural habitat, here's a spot within S.F. city limits where an endangered-species sighting is guaranteed. The critically endangered scimitar-horned oryx and Waldrapp ibis can be viewed without resorting to camouflage. Daily, 10 a.m.-5 p.m., Sloat Blvd. and 47th Ave., S.F. (415) 753-7080, www.sfzoo.org.