Vasona Lake County Park is generally best for birding in fall and winter, when rare warblers (fall) and sapsuckers (winter) may appear. Spring is generally not as popular as fall, but rarities such as Yellow-breasted Chat have been recorded during that season.

During fall, many warblers and other songbirds, including Western Tanager, pass through the park. In recent years, this has been one of the best places in the county for rare eastern warblers. Some of the better areas to check for fall migrants are the dense riparian at the south end of the lake just south of the large red bridge (and east of the car bridge), the trail on the west side of the lake, and the Los Gatos Creek Trail to the west of the car bridge. The dense riparian near the red bridge has had Northern Waterthrush in past years, and there is one record of Louisiana Waterthrush as well. Yellow Warblers are very common both here and elsewhere through the park during migration. American Redstart is rare, but sometimes appears in fall in the riparian along Los Gatos Creek (both west and east of the car bridge). Finding an area of the creek with water and waiting there during fall can be productive for songbirds coming to drink; good places to do this include the riparian near the bathroom to the south of the red bridge and a small area just to the west of the car bridge on the Los Gatos Creek Trail. Finally, the trail along the west edge of the lake can also be productive for warblers (particularly past the end of the paved portion), including vagrants such as Blackpoll Warbler. It was this location where the first county record of a Bay-breasted Warbler was recorded in 2020. In addition, checking the grassy fields for flocks of sparrows can be productive for rarer species, such as Clay-colored and Vesper Sparrow.

During winter, most of the warblers and songbirds leave, but are replaced with large numbers of Yellow-rumped Warblers. Several Red-breasted Sapsuckers also arrive and winter in the park, and occasionally, a rarer Yellow-bellied Sapsucker will appear. In October 2021, a male Williamson’s Sapsucker - a very rare bird in the Bay Area - was found near the boat launch parking lot, where it stayed until February 2022. It later appeared the following winter in February 2023 in the same area, and may return again for another winter. Finally, checking the lake may turn up various waterbirds, and could be a good place to check for seabirds following a winter storm.

Yellow Warbler, Western Tanager, Black-throated Gray Warbler, occasional fall vagrant warblers (Blackpoll, Northern Waterthrush, American Redstart, etc.), Red-breasted Sapsucker (winter), other sapsuckers (winter, very rare), Green Heron, Clay-colored Sparrow and other uncommon sparrows (fall, rare).

Vasona Lake County Park is located in Los Gatos. Habitat here includes a large lake (Vasona Lake), creek riparian, and grassy meadows. Some eucalyptus trees are also present.

To get here from North San Jose/Milpitas, take Hwy 880/17 south towards Santa Cruz and take Exit 20B (Saratoga-Los Gatos Road). Turn right on University Ave., and then turn right on Blossom Hill Road. Turn left at Roberts Road, which will then bring you to the entrance. To get here from Palo Alto/San Francisco, take Hwy 101 south and exit on Hwy 85 south going towards Cupertino. Exit on Winchester Blvd. and turn right. Then turn left onto Blossom Hill Road and make a left at Roberts Road. To get here from South San Jose, take Hwy 85 north and exit on Bascom Ave/Los Gatos Blvd. Turn left and continue straight until Blossom Hill Ave. Turn right and continue until Roberts Road, then turn right at that intersection. There is a $6 entrance fee.

Vasona Lake Trail, Los Gatos Creek Trail