Calero Reservoir (Late Winter/Early Spring):
Dancing Western and Clark’s Grebes
by Brooke A Miller
January through March, Western and Clark’s Grebes are performing their spectacular courtship displays. Calero Reservoir in San José south of Almaden Valley can be a fairly easy place to watch them.
Trip Covers: January - March
Key Birds: Ducks, Western Grebe, Clark’s Grebe, Osprey, White-tailed Kite
How to Bird
This field trip covers the Calero Reservoir boat launch area. It is one of three entrances to Calero County Park, and it is open year-round to power and non-power vessels. Mornings are the best time to see the dancing grebes and weekdays are preferred, as during the weekends there are a lot of boats on the water which can push the bird activity farther away. You will need binoculars and, if you have a scope and/or camera, you may want to bring those as well. Bring a beach chair if you’d like to sit and watch the birds for an extended period of time.
Park at the boat launch parking lot, just inside the park entrance at 23205 McKean Rd (pin 1 on map). Check the reservoir for Western and Clark’s Grebes. They tend to be in the areas west of the parking lot but if you see them close by, head down the short path (pin 2) from the parking lot to the water’s edge (pin 3) and set up your chair. To check the west areas of the reservoir, use the primitive trail (pin 6) that follows the reservoir to the west and then southwest. Along this primitive trail there are two dams (pins 7 and 8). Note that the water in front of the second dam cannot be seen from the boat launch area and the grebes can be here or in front of the first dam. Alternatively, if you see them to the east, there is a primitive trail (pin 4) that goes east from the boat launch towards the eastern end of the reservoir (pin 5). Along these primitive trails you may encounter Rufous-crowned Sparrow, Spotted Sandpiper, Song Sparrow, Savannah Sparrow, Red-winged Blackbird and Western Bluebird.
Once you get to the grebes, you will most likely need time, patience and an understanding of what to look for Western and Clark’s Grebes have similar displays, but their vocalizations are a bit different. Here is how All About Birds describes it:
“The famous “rushing ceremony” begins with the birds delivering a rolling ”cree” (Clark’s Grebe), or double call (Western Grebe). Then the birds lower themselves in the water, giving a grating, ratchet-like call with crest raised and throat distended. The next step involves dipping the bill and head into the water, then raising and shaking the head. Then comes the spectacular rushing: both birds rise up in the water onto their feet, side by side, and simultaneously “run” for long distances across the surface of the water, wings held up and back, necks gracefully arched, pattering with their powerful feet in what looks like a perfect bird ballet. The display concludes with a sudden dive.”
Courting Grebes at Calero Reservoir by Steve Patt
These two species look very similar, so how do you tell the difference between Clark’s and Western Grebes? Clark’s Grebes have a bright yellow-orange long bill, eyes in the white feathered portion of their face, and their call is a one-syllable “cree”. Western Grebes have a duller green-yellow bill, eyes in the black feathered portion of their face, and a two-syllable “cree-cree” call. The easiest way to remember the difference between the two calls is that “Clark’s” and “cree” each have one syllable while “West-ern” and “cree-cree” have two syllables.
Clark’s Grebes by Brooke Miller
Western Grebes by Brooke Miller
Each species usually mates with their own species but don’t be surprised to find a Western Grebe dancing with a Clark’s Grebe. They can inter-breed. Please see the All About Birds species pages (links below) for more information.
You may see a lot of discarded fishing supplies along the lake. Did you know that fishing line, weights and hooks that are caught in vegetation, lost in the water, or left behind on the bank pose hazards to birds. See how you can help, read “Fishing Line: Don’t Catch a Bird!”
While at Calero Reservoir you can also bird the parking lot and picnic areas in search of Swallows (Tree, Violet-green, Barn, and Cliff), White-tailed Kite, Red-winged, Tricolored and Brewer’s Blackbird, Bald Eagle, Osprey, Common Merganser, American Pipit, White-throated Swift, Double-crested Cormorant, and at the end of March, returning Caspian Terns.
A few words about the primitive trails: these trails do not show up on the park map and have been made by fisherpeople looking for good places to fish. You will need to wear decent footwear to navigate these trails (no sandals). The narrow dirt trail to the second dam is approximately 1 mile each way. The narrow dirt trail from the boat launch to near the east end of the reservoir is approximately 0.3 miles each way. Both trails are fairly flat, but there are areas with rocks where footing could be an issue. There is no tree canopy over either of these areas.
Calero Reservoir by Brooke Miller
Ready for More? Calero County Park has two other areas you may want to explore: the main entrance (SE on McKean Road, Latitude/Longitude: 37.172723, -121.759109 and the Rancho San Vicente entrance (NW on McKean Road, Latitude/Longitude: 37.193987, -121.807061. Rancho San Vicente is a great place to see Rock Wrens. Read more about this location here.
Interactive Map
Directions
The boat launch area is located off McKean Road. Latitude/Longitude: 37.188137, -121.774463
Traveling from Central San Jose, take Almaden Expressway south to Harry Road. Turn right onto Harry Road, then left onto McKean Road. The reservoir is on the right, about 3 miles south of Harry Road.
Alternatively, from US-101, exit Bailey Ave west. Follow Bailey Ave for 3 miles to McKean Rd. Turn right and continue about 0.5 miles. The entrance to the reservoir will be on your left.
Boat launch parking area for Calero Reservoir. Photo by Brooke Miller.
Parking: Paved and dirt parking lots, ADA Compliant parking spots
Fees: Day-use parking fees. See the park website for more information.
Public Transportation: None
Park Hours: 8 am until sunset
Facilities: Wheelchair accessible porta-potties, drinking fountain, picnic tables, cell phone service.
Trip Mileage: Variable. This location is good for parking lot birding or you can try several short (1 mile or less) primitive trails.
Trail Conditions: Crowded on weekends, no shade, narrow dirt trails.
Accessibility: The parking lot is wheelchair accessible and is good for birding. The short trails to the shoreline and the primitive trails are not wheelchair accessible.
Bikes: Not a bike trip.
Dogs: Dogs are allowed on 6-ft leash
More Information
eBird hotspot: Calero Reservoir
All About Birds: Western Grebe and Clark’s Grebe
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: Western and Clark’s Grebes by Brooke A Miller
Last Updated: 4/19/2022
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