The Pacific Flyway is the western corridor of North American bird migration, stretching from Alaska to Patagonia. Along its length, birds require reliable stopover points — places to rest, refuel, and wait out the seasons. The Salton Sea sits at a critical junction in the Sonoran Desert, surrounded by hundreds of miles of arid terrain, and for migratory waterfowl the refuge at its south end is not merely convenient but essential. Over 400 bird species have been recorded here. Yuma Ridgway's rails — an endangered subspecies with secretive habits and a distinctive rasping call — nest in the refuge's bulrush marshes. Eared grebes arrive by the millions in winter, drawn by the brine shrimp that thrive in the sea's hypersaline waters. Even as the sea itself recedes, the refuge's managed wetlands provide a buffer zone that sustains populations of birds that have nowhere else to go in this stretch of desert.

The refuge was established in 1930, making it one of California's older wildlife preserves, with an original designation of 32,766 acres that has since grown. Its character is shaped less by dramatic scenery than by careful management: dike systems, water control structures, and agricultural fields deliberately flooded to attract waterfowl. Visitors willing to walk the Rock Hill Trail — about two miles roundtrip — discover a landscape that rewards patience over spectacle. The trail winds past shallow impoundments where stilts and avocets wade in formation, and the Michael Hardenberger Trail offers a shorter half-mile loop closer to the refuge headquarters. Neither trail is crowded. This is not a destination most tourists seek out, which is part of its appeal to birders who arrive before dawn and stay until the light fails.

The refuge carries the name of Sonny Bono — the entertainer-turned-politician who represented California's 44th congressional district and became an unexpected champion for the Salton Sea before his death in a skiing accident in January 1998. As a congressman, Bono had grown alarmed by the sea's ecological decline and pressed for federal attention to its crisis long before the problem became impossible to ignore. Congress renamed the refuge in his memory, a gesture that felt appropriate given the sea's strange celebrity past and its equally strange present. The politics of the Salton Sea have remained contentious ever since.

The Salton Sea has been shrinking since water agreements between California and Arizona reduced the agricultural runoff that had sustained it. As the shoreline retreats, it exposes dry lakebed laden with fine dust, fertilizer residue, and pesticides — a public health concern for the communities downwind and an ecological disaster for species that depend on shallow-water habitat. The Salton Sea Management Program's Phase 1 plan, covering 2018 through 2028, carries an estimated price tag of $420 million and aims to create shallow wetland habitats along the exposed playa to replace what the sea is losing. The refuge sits at the center of this effort. Whether the managed wetlands can compensate for the sea's contraction remains an open question, but the refuge's managers are working with a sense of urgency that the birds themselves seem to share — arriving each year in numbers that suggest the habitat still works, even as the margins narrow.