New Chicago Marsh and EEC (Spring):
Spring Magic Up Close!
by Mike Ambrose
The San Francisco Bay is a critical habitat in spring, both as a migratory stopover and as breeding grounds for many birds. Birding at the Don Edwards National Wildlife Refuge Environmental Education Center (EEC) in Alviso allows close views of the extraordinary species diversity that makes use of this habitat, all in a short distance on flat ground.
Trip Covers: April - June
Key Birds: Black-necked Stilt, Barn Swallow, Savannah Sparrow, Common Yellowthroat
How to Bird
Caveat: Spring is an incredibly important and challenging time for birds, so it’s an especially crucial time to be a conscientious observer. Don’t closely approach bird nests and pay attention to how birds are reacting - if they seem disturbed by your presence, back away until they’re no longer paying attention to you. In addition, don’t play back recorded bird song.
Boardwalk behind the Environmental Education Center
The EEC sits at the intersection between New Chicago Marsh, Salt Pond A16, and Mallard Slough. This combination of marsh and salt pond habitats, plus the nearby butterfly gardens, create a productive and varied habitat for many species of birds. This field trip will take a quick walk through each of these habitats. There are no wrong turns here - if you decide to deviate from the trip, you’ll find more of the same incredible habitat - but we’ll walk through the shortest, most densely birdy patch.
Starting at the parking lot, we’ll walk towards the boardwalk, near the EEC building (see the map for the exact location). Before we even get on the boardwalk, check out the owl box on the small building across from the main EEC building (again, exact location on the map). Barn Owls are regulars in this box, and at the right time of year you can see chicks as well. If you don’t see anything in the box, try moving around - the exact angle is hard to find.
With that diversion out of the way, let’s walk onto the boardwalk. I like to take a second to close my eyes and really listen to the sounds of the marsh. You’ll probably initially be drowned out by honking Canada Geese and quacking Mallards, but if you focus on high-pitched sounds, you might be able to hear the lovely song of the Savannah Sparrow. They also like to perch on the sides of the boardwalk - look for small sparrows with a yellow eyebrow and pink feet.
Savannah Sparrow by Raechel Lee
One of the most prominent species here is Black-necked Stilt, which breeds in the marsh. Look closely and you’ll see differences in color between different individuals - stilts with dark shiny all-black backs are males, whereas females are dark chocolatey brown instead. In May, these stilts will be nest-building, and some may have already laid eggs. If you come back in June, you might get a chance to see some downy chicks. Repeated trips back lets you watch these adorable babies grow up all the way through adolescence. It’s an incredible opportunity to get to study these birds up close throughout their life cycle.
Recently hatched Black-necked Stilt by Mike Ambrose
Juvenile Black-necked Stilt by Mike Ambrose
While Black-necked Stilts may be the smartest-looking (and possibly loudest) of the bunch, there are many other shorebirds to be on the lookout for as well. American Avocets will be molted into the peach-colored head they have in breeding season, and keep a lookout for other, less common shorebirds like Greater Yellowlegs. Observers with an eye to the sky could see Forster’s Tern, Caspian Tern, and even the occasional Black Skimmer - all of which breed on islands in Salt Pond A16.
At the end of the boardwalk, there is a bridge leading to a ramp up to A16. This bridge is a favorite spot of swallows, especially Cliff Swallow and Barn Swallow, which frequently spend time underneath the bridge.
Barn Swallow by Barbara Coll
A16 itself is host to many ducks in winter, but we’ll be a little past their peak time. Nonetheless, there will also be some lingering ducks - Ruddy Ducks, Gadwalls, and more. You’re also likely to see some more Canada Geese which nest along the edges of the pond. Keep an eye out for terns as you turn right and head along the trail until a nearly-invisible right turn takes you to a floating dock (see location on map).
Floating dock at low tide
This floating dock takes you right along Mallard Slough and is a fantastic opportunity to do some slower-paced observation of birds. Listen to the incessant song of Marsh Wrens, the sweet warbles of Common Yellowthroat, and keep an eye on the reeds to try to spot a Sora or Virginia Rail. If the tide is high, you can enjoy ducks lazily floating down the river - if it’s low, you’ll sometimes find shorebirds making use of the nutrient-rich shores of the river. Regardless, this spot is so quiet and peaceful that, even if no birds show up for you, it’s worth a stop.
Common Yellowthroat by Susan Weinstein
We’re going to finish this tour by walking through the gardens around the EEC. Walk back along the A16 path as if you were returning to the boardwalk, but take the left turn along the paved path instead. Walk along this path (with Mallard Slough to your left) for a few hundred feet, then turn right and take the stairs into the garden.
Stairs into garden
The garden areas of EEC have historically been home to some amazing rarities - including Bell’s Vireo, Rose-breasted Grosbeak, Green-tailed Towhee, Eastern Kingbird, and much more. There’s no particular path to follow here, and the gardens extend across the street as well - walk as long as you like. You’ll certainly see and hear some of our most common local species, like House Finch, Bewick’s Wren, and Northern Mockingbird, but you have a good chance to find more as well. Scan the trees for Bullock’s Oriole. Listen for the falling trill call of Orange-crowned Warbler and look for the neat black cap of Wilson’s Warbler. Other, rarer warblers and other migrants are possible too - look carefully at every bird you can!
Once you’ve had your fill of garden birds, the field trip is over, and you should end up right where you began! I hope you’ve enjoyed your time here, and I encourage you to come back frequently - there’s tons to see at any time of year, and there are no bad days here.
Ready for More? More of the New Chicago Marsh can be seen along the entrance road, and the trail along A16 wraps all the way around. Check out the summer self-guided field trip to A16 for more details. If you’re visiting in fall or winter, check out the fall self-guided field trip to New Chicago Marsh.
Interactive Map
Route Summary
From the main parking lot, follow the boardwalk through New Chicago Marsh
Turn right and walk along A16 to the floating dock
Retrace your steps back along A16 until you turn left along the paved path
Wander through the gardens as much as you like!
Directions: From CA-237 exit north onto Zanker Rd. Continue on Zanker Rd for about 2.5 miles (Zanker Rd becomes Los Esteros Rd). Make a sharp right turn onto Grand Blvd. A small dirt parking lot (GPS: 37.435859, -121.958096) is on your left in ½ mile. If the main gate is open, continue another ¼ mile past the dirt lot into the main parking lot (GPS: 37.439150, -121.959655). Note: do not leave your valuables in the car.
Parking: Large paved parking lot with ADA compliant spots is open from 7 am - 5 pm daily. There is a small dirt parking lot just outside the main gate. No fees for either parking area.
Fees: None
Public Transportation: None
Hours: The trails are open sunrise to sunset. The main parking lot is open from 7am - 5pm.
Facilities: Wheelchair accessible porta-potty in main parking lot, cell signal typically strong
Trip Mileage: less than 1 mile
Trail Conditions: Flat trail, mix of paved, packed dirt, and boardwalk. Full sun exposure throughout.
Accessibility: The boardwalk trail is wheelchair accessible, although the road running along A16 may be too uneven. Benches regularly available throughout the trail.
Bikes: While this trip is a bit short to do by bike, biking along the rest of A16 and beyond is an excellent trip
Dogs: Dogs are not allowed
More Information
eBird hotspot: Don Edwards NWR--Env. Ed. Ctr. (EEC) and nearby upland areas
More Resources
For more trips like this one, visit Self-Guided Field Trips.
Visit the SCVAS Birding Resources page for more information on where to bird, our birding community, bird identification resources and more.
Read “What to Look for Now” by SCVAS Executive Director Matthew Dodder.
Banner Photo Credit: Don Edwards Environmental Education Center by Eve Meier
Last Updated: 3/13/2022
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