The Light-footed Ridgway’s Rail (Rallus obsoletus levipes), a secretive marsh bird, depends on healthy coastal wetlands, especially salt marshes like those at Upper Newport Bay Ecological Reserve (UNBER) in the Ecological Health Assessment Study Area. Wetland loss, degradation, and sea level rise have cost it much of its nesting habitat (e.g., Pacific cordgrass), leaving it vulnerable to flooding and predation. Coastal California has already lost most of its wetlands, and projections indicate that up to 80% of remaining rail habitat could disappear by the end of the century.
At UNBER, Ridgway’s Rail numbers have plummeted from 234 pairs in 2015 to just 36 in 2023, while nearby San Joaquin Marsh has recently seen small but promising increases. Along with reduced cordgrass habitat, predation by raccoons and raptors is a major concern. Conservation efforts include predator management, marsh restoration, captive breeding programs, and the use of artificial rafts to provide temporary nesting and refuge sites. Ridgway’s Rail population trends serve as a clear indicator of marsh health and highlight the urgent need for large-scale wetland restoration.
Additional monitoring and surveys could include:
- Continuing call-count surveys to create a new baseline against which to compare data in the future.
- Surveying high-tide habitat use (via kayak or with a scope) to determine specific habitat used by Ridgway’s Rail and whether the birds are consistently using artificial rafts during high tides.
- Continuing marsh vegetation surveys using methods similar to past surveys.
- Monitoring marsh elevation over time.
- Surveying predators.
