Zapata Swamp
The species appears to have been easily found in the Santo Tomás area until 1931, but there were no further records until the 1970s when birds were found 65 km (40 mi) away at Laguna del Tesoro. The few records in subsequent years suggest that numbers remain low, although after no official sightings for two decades, a 1998 survey found the birds at two new locations in the Zapata Swamp. Ten rails were detected at Peralta, and seven at Hato de Jicarita. On the basis of this sample it was estimated that 70–90 rails were present in the 230 hectares (570 acres) between the two sites. As of 2016, the only sighting for several years was in November 2014.