Chesbro Reservoir (Winter):
A Serene Setting for Raptors and Waterfowl
by Jennifer Oliver
Wintertime is an especially wonderful season to spend in the lush green Bay Area foothills, as well as enjoying the wintering birds. Chesbro Reservoir provides a location where you can do both. It’s a peaceful, less-crowded location where you can just stop and exhale. An excellent spot to view both a variety of waterfowl and raptors, there are also small shorebirds, woodpeckers, and brush inhabitants. Chesbro Reservoir is located 3 miles west of Morgan Hill.
Trip Covers: November - March
Key Birds: Wood Duck, American Wigeon, Green-winged Teal, Ring-necked Duck, Bufflehead, Common Merganser, Killdeer, Spotted Sandpiper, Double-crested Cormorant, American White Pelican, White-tailed Kite, Red-shouldered Hawk, Red-tailed Hawk, Acorn Woodpecker, American Kestrel, Hermit Thrush, and maybe an occasional Bald Eagle or Osprey
How to Bird
Chesbro Reservoir County Park is located about 3 miles west of Morgan Hill in the nearby foothills. It is composed of 650 acres, including a 269 acre reservoir, which is a popular fishing spot. Chesbro Reservoir was formed with the damming of Llagas Creek in 1955 – to ensure adequate water supply for the growing population in the county. The reservoir gets its name from Elmer J. Chesbro, who was a local doctor and president of the Santa Clara Valley Water Conservation District at the time the dam was constructed. Historically this area was part of 30,000+ acres of land grants from Mexican Governor Figueroa granted in 1834-35.
Although there are no designated trails around the reservoir, it can still be a good site for birding. It is usually very quiet, with only a few fishermen pulled off alongside the road here and there. The peaceful surroundings and lush green foothills are what make this a gem of a place to bird-watch in the winter. Social distancing is not a concern.
On this trip you may choose to stop at a pullout or two along the way, or just drive directly to the main parking lot on the east side of the reservoir. From there you can walk to the dam, across the dam walkway, and a short loop behind the dam (with a fairly steep gravel pathway) – a total of 1.1 miles of walking distance.
View from a pull-out, on the west side of the reservoir. The trees near water’s edge and brush in the water are prime birding spots. Photo by Jennifer Oliver.
As you are traveling east on Oak Glen Ave., you will see multiple dirt/gravel pull-offs. (See pins 1 and 2 on the interactive map for suggested stopping spots.) If it’s not too muddy, then these can be good stops along the way. Depending on the water level of the reservoir, the western side of the reservoir where the water is shallow and there is quite a bit of brush can be an ideal spot for waterfowl and raptors fishing. (Note: As with any pull-off area, be careful getting back onto the road with on-coming traffic.) In these areas, see if you can spot the American White Pelicans. Many times they are napping on the water, but if you get a chance to see them take flight, it can be quite a site – as they have an impressive 108” wingspan! You may also spot a variety of other water birds such as: Buffleheads, Wood Ducks, American Wigeons, Ring-necked Ducks, Common Mergansers, Green-winged Teals, Canada Geese, American Coots, Double-crested Cormorants, Great Egrets. Be sure to look closely in the brush in the water as many times they can be somewhat hidden. This is when a pair of binoculars can be very helpful!
American White Pelican. Note the hump or “horn” on the pelican’s bill. It is used to attract a mate during breeding season, and will fall off after the birds have mated and laid their eggs. Photo by Jennifer Oliver.
Also peruse the nearby trees, into the hills, and keep an eye out overhead. These foothills and the nearby Coyote Valley OSP are home to quite a few birds of prey in the winter months – such as Red-tailed Hawks, Red-shouldered Hawks, White-tailed Kites, Bald Eagles, American Kestrels, Turkey Vultures, and Ospreys.
American Kestrel. American Kestrels are the smallest of the North American falcons. Like other falcons they swoop down from a high perch to capture their prey – which for the kestrels includes mostly large insects, but also voles, mice, small birds, lizards, frogs. Photo by Jennifer Oliver.
Osprey overlooking the water. Interesting tidbit: Osprey always fly with their freshly caught fish with the head always facing forward. This allows for the least amount of wind resistance. Photo by Jennifer Oliver
You may also hear an occasional loud ruckus from some Red-winged Blackbirds – as many times there are large clusters in the treetops or flying overhead. At times it can be quite comical to observe when these birds decide to pester the larger birds!
Main parking lot (with port-a-potty facility). Photo by Jennifer Oliver.
Next continue driving east on Oak Glen Ave. until you reach the paved parking lot (on the right side of the road, see pin 3 on the interactive map below). See if you can hear the California Quail hiding in the brush or running around nearby. From the parking lot you have a good vantage point across the water to the dam. Also track along the waterline. Do you see any small shorebirds – such as Killdeer or Spotted Sandpipers? You may also choose to walk down the nearby boat ramp to view the waterline more closely.
California Quails. The plume on a quail’s head is larger on the males (as shown above) than on females. Each consists of 6 overlapping feathers. Photo by Jennifer Oliver.
From the parking lot, head east along Oak Glen Ave. on foot. Carefully stay on the shoulder of the road until reaching the dam walkway entrance. Listen for birds in the trees and bushes along the way. About halfway there you will see a large eucalyptus tree on the right. This tree is always a good spot to look and listen for birds such as Oak Titmice, Yellow-rumped Warblers, and Spotted Towhees. The oak tree across the road is also a favorite spot for Acorn Woodpeckers. (See pin 4 on the interactive map below.)
Walking along Oak Glen Ave. with the large eucalyptus tree shown here. Photo by Jennifer Oliver.
Once you reach the dam walkway, walk across and look for more waterbirds along the dam. (See pin 5 on the interactive map below.) Here you may see Great Blue Herons, Mallards, American Wigeons, Green-winged Teals, Canada Geese, American Coots, Double-crested Cormorants, just to name a few.
Green-Winged Teal. Green-winged teals are the smallest of the dabbling ducks in North America. What is a “dabbling duck?” It refers to ducks that feed primarily along the surface of shallow water and do not dive down into the water for food. They have broader bills to help with this type of feeding. Photo by Jennifer Oliver.
Walk to the end of the dam walkway and then follow the loop around the backside of the dam. (See pin 6 on the interactive map below.) This path is fairly steep and has some loose gravel, so be cautious. This back loop area is full of quite a bit of brush and is an excellent area to spot Hermit Thrush in the wintertime. Also seen in this area may be Northern Flickers and Nuttall’s Woodpeckers in some of the trees.
Hermit Thrush are typically found in denser brush areas or hopping around on the ground. Photo by Jennifer Oliver.
Walk back to the main parking lot by the same path – by going back up and across the dam.
Fairly steep gravel trail behind the dam. Photo by Jennifer Oliver
Ready for More?
Also check out the nearby self-guided field trips for Old Oak Glen Ave. and Calero Reservoir.
Interactive Map
Route Summary:
Optional: Stop at pull-out(s) along Oak Glen Ave.
Drive to main parking lot on east side of reservoir
From the parking lot, walk along the shoulder of Oak Glen Ave. for 0.2 miles
Walk across the dam for 0.15 miles
Turn left at the end and walk down, around the trail loop behind the dam for 0.4 miles
Walk back across dam and to parking lot – 0.35 miles
Directions: From US-101, take the Bailey Avenue exit and go west all the way up to McKean Road. At McKean Road, turn left (south) and go approximately 4.5 miles, then turn left at the Oak Glen Avenue / Chesbro Reservoir sign. Stay left at the fork in the road. Either continue on Oak Glen Ave. for 2.5 miles to the main parking lot Latitude/Longitude: 37.118534, -121.695839, or you may choose to stop along the occasional dirt/gravel pull-outs to view as you go.
Parking: There are small gravel/dirt pull-outs along Oak Glen Ave., but the main parking lot (paved) is at the far east side of the reservoir near the dam. Parking includes ADA compliant parking spots. (Be cautious of traffic when pulling in and out of the pull-outs along Oak Glen Ave.)
Fees: None
Public Transportation: None
Park and/or Trail Hours: 8 am to Sunset
Facilities: 1 porta-potty, cell phone service
Trip Mileage: Variable. You may choose to observe from a few pull-outs off the main road and/or the main parking lot. You can also walk on the shoulder of Oak Glen Ave. and back behind the dam (1.1 miles round-trip).
Trail Conditions: There are no trails along the reservoir. Besides the main road and parking lot, all other areas are gravel/dirt. Also it should be noted that the trail going down behind the dam is fairly steep with loose gravel.
Accessibility: Only the main parking lot is wheel-chair accessible.
Bikes: Allowed but not recommended.
Dogs: Dogs are allowed if on a 6 ft. (or shorter) leash.
More Information:
eBird hotspot: Chesbro Reservoir
All About Birds: American White Pelican and American Kestrel
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: Chesbro Reservoir by Jennifer Oliver
Last Updated: 2/28/2022
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