Wildlife Diversity Program Quarterly Report for October–December 2025
What We Are Learning About the Elusive Black Rail From a Dry Year by Kacy Cook, Waterbird Biologist and Brooke Callisto, Waterbird Technician
T he low amounts of precipitation and lack of major storms during 2025 provided an opportunity to gain insight into Black Rail habitat use during a period in which water levels in coastal marshes were relatively low through most of the breeding season. We conducted Black Rail call-response surveys at 17 points, 4 to 5 times each, in or near unburned (not burned in at least 10 years), high elevation coastal marsh. We only detected Black Rails at 2 points. These 2 points were on the edge of fairly large pools with some standing water and a diversity of high marsh herbaceous plant species. The points with no detections were in high marsh at pools with no standing water, in more narrow coastal marsh with no obvious pools, or in wide marsh with pools dominated by sawgrass (Cladium), where herbaceous plant diversity was low. Analyzing the audio recording data from 26 Autonomous Recording Units (ARUs) that were deployed throughout the 2025 Black Rail breeding season produced a variety of results. No Black Rail detections were recorded by any of the 8 ARUs deployed at Swanquarter National Wildlife Refuge (SQNWR) in an unburned sawgrass dominated marsh covered in standing water. Black Rail calls were detected on 2 dates by 1 ARU placed adjacent to high elevation marsh dominated by saltmeadow cordgrass at SQNWR. An area of unburned high marsh with a diversity of plants and an area of mid-elevation marsh dom- inated by black needlerush, both known to support a population of Black Rails, produced multiple Black Rail calls at each of 6 ARU points. At a different unburned site, Black Rail calls were detected at 8 of 11 ARU points in marsh dominated by black needlerush in the interior of the marsh near high marsh herbaceous vegetation and pools with standing water. One of these 8 points had only 1 Black Rail call and it was in high marsh near the forest edge in an area without pools. The 3 points without calls were at pools within black needlerush-dominated marsh, but not near high marsh vegetation or were at the sound-edge of the marsh. We look forward to continuing surveys and monitoring of Black Rails to better understand the role of water levels, fire, and annual precipitation pat- terns play in the presence of this cryptic species.
Technician Brooke Calisto conducting BLRA veg surveys.
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