Oso Flaco is a freshwater lake sustaining a wealth of flora and fauna tucked inside the Oceano Dunes near the northern end of Santa Barbara County by Guadalupe. Concealed by the dunes, the lake is usually serenely quiet, but it’s not uncommon for the silence to be broken by some of the 200 bird species bathing in the water, wings furiously flapping, or a great blue heron squawking in flight, pterodactyl-like, just above the dewy mist hovering over the lake.
The lake got its unique moniker when two explorers from Gaspar de Portola’s 1769 expedition hunted and ate a skinny black bear along the shoreline. The story goes that the Chumash had been competing for food with the bear so, they fed it tainted meat. Several of the conquistadors who ate the infected flesh later died as a result.
A manager of the Guadalupe-Nipomo Dunes National Wildlife Refuge once told me it was possible to see endangered California least terns roosting on the boardwalk that crosses the lake during the summertime, when the parents teach their fledging chicks how to fish from the railings. Though they’re the smallest species of tern — hence the “least” — what these aerodynamic birds lack in size they make up for in entertainment, especially in their aerial assaults on tiny schools of freshwater fish.
Like the also-endangered snowy plover, least terns nest in the natural depressions of the nearby sand dunes. The parents will hunt fish at the lake, typically with the females waiting on the railing as their mates arrive with beaks full of fish. After the transfer is easily made, the females fly off to their nests.
The best time to catch this behavior is early in the morning, when weather conditions are calm and Oso Flaco Lake epitomizes tranquility. See dunescenter.org for more info.