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Field Trip: A Noisy California Gull Colony - Palo Alto Flood Control Basin

  • 37.433605, -122.099551 (map)

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California Gull by Mary Ann Robertson

A Noisy California Gull Colony

Breeding California Gulls in the South Bay have been monitored since 1980 when there were only 24 gulls. A survey in 2021 showed 9,159 nests at the Palo Alto Flood Control Basin out of 22,647 in the South Bay, about 40% of the total breeding population.

We will walk the Adobe Creek Loop Trail to an area across from the basin islands used for nesting by California Gulls. There we will scan for nests, fuzzy gray chicks, and maybe some early fledglings for about 30 minutes. On the way back we will meander and look for shorebirds on Charleston Slough on the left and ducks and pelicans in Adobe Creek on the right. At the pump house we'll look for Barn and Cliff Swallows. For a preview check out https://scvas.org/self-guided-birding/california-gull-colony

Trip Difficulty: about 3 miles round trip. Paved from the trailhead to the intersection of Bay Trail and Adobe Creek Loop Trail. The Adobe Creek Loop Trail is wide, packed dirt with some gravel (wheelchair accessible). The colony can be viewed from the trail; secondary paths nearest the colony (at the waters edge) are not recommended for wheelchairs. There is no elevation change. No shade; several benches along the way.

Other Trip Notes: Bring your binoculars, and if you have them, cameras with telephoto lenses, and spotting scopes. Charleston Slough high tide (4.99 ft.) is at 8:54 am so tide will be going out in the slough when we walk back to the trailhead.

Leaders: Mary Ann Robertson (650) 521-3910 (voice only in the field) and Diane McCoy (650) 714-3769

Beginner Friendly

Meet: at the trailhead at the intersection of San Antonio Road and Terminal Boulevard

Directions: From US-101 in Mountain View, exit San Antonio Rd. Continue north to the end of San Antonio Rd then turn right onto Terminal Blvd. Park along Terminal Blvd. Latitude/Longitude: 37.433605, -122.099551

Facilities: Wheelchair accessible restroom; drinking water at trailhead. Cell phone service is good.

Parking Type and Fees: Free, along Terminal Boulevard. There are two ADA parking spots and a curb cut and path leading to the trailhead at the San Antonio Gate.

Questions? Email general questions to fieldtrips@scvas.org or contact the trip leader for questions regarding the event.

Earlier Event: June 8
Field Trip: Rancho Cañada del Oro
Later Event: June 12
Field Trip: Charleston Slough