Oso Flaco Lake will offer good birding all months of the year. Walk the willow-lined causeway and look through the dense riparian habitat on both sides of the road. Flocks will move through this stretch of willows containing a mix of resident and migrant birds during spring and fall migration. When you reach the lake at the end of the causeway, continue up the dune trail, or take the footbridge over the lake for excellent views of the surrounding water from an elevated vantage point. From the end of the footbridge, a boardwalk trail continues through the dunes all the way to the beach. Avoid hiking into sensitive habitat areas off the boardwalk.

Migrant passerines include warblers, flycatchers, and vireos. Nesting Allen's Hummingbird, Chestnut-backed Chickadee, Swainson's Thrush, and Marsh Wren are expected in summer. Flocks of swallows and swifts will pass overhead during migration. Waterfowl, cormorants, and gulls are common on the lake in fall and winter. Look for Virginia Rail, Sora, herons, egrets, and bitterns along the lake margins. Shorebirds may be present when water levels are low. Least Terns are commonly seen fishing over the lake or may be found perched on the bridge railing during the breeding season. In the ag fields off the parking lot, look for sparrows, American Pipits, and roosting Black-bellied Plovers which are sometimes present after the fields have been tilled. Several rare birds have been found at Oso Flaco Lake making it a popular birding spot during fall migration.

Located just off scenic Highway 1 north of Guadalupe in southern San Luis Obispo County, Oso Flaco Lake is an 800-acre day-use area in the southern portion of the Oceano Dunes SVRA. It is part of the 22,000-acre Guadalupe Nipomo Dunes Complex and is one of the two coastal access points in Santa Maria Valley, with the other being the Rancho Guadalupe Dunes Preserve. This land is designated for hiking, fishing, bird watching, nature study, and other non-motorized uses. The trail is approximately 1 mile from the trailhead to the beach overlook; a 2.2-mile total round trip.

The parking lot is located at the west end of Oso Flaco Lake Road.

The trail and parking lot are open from sunrise to sunset. Day-use fees may apply, but a note at the kiosk reads "Temporary free parking." Parking in the lot has been free for some time, but this could change. Some will park along the stretch of road outside the lot avoiding the parking fee. The trailhead begins through the white gate at the parking lot. Take valuables with you and do not leave items visible inside your car. Dogs are not permitted in the day-use area of Oso Flaco Lake, including the trails, boardwalk, and beach. Be prepared for dense fog or breezy conditions. Oso Flaco Lake may be closed after periods of heavy rain due to flooding.

NOTE: On January 6, 2024 a fire burned the middle section of the bridge that goes across the lake. State Parks has closed the portion of boardwalk that was burned, but the public will still be allowed to access the front and back sections of the boardwalk to bird and fish. An alternative beach access route will now go through the maintenance road which goes around the lake and then back on the boardwalk. An access sign is posted where the approved trail is located. State Parks will be assessing the boardwalk damage and working towards restoring the bridge in the coming months.

As indicated by the name, use this Hotspot for birds found from the parking lot, causeway, lake areas, and boardwalk only. Please use the separate Hotspot, Oso Flaco Creek Mouth/Beach when you reach the ocean. This will appropriately tie species to their habitat.

The AllTrails website has a description and map of a hike on the Oso Flaco Lake Trail.