Notes on a population of ocellated crake (Micropygia schomburgkii) in Misiones province: a new rail for Argentina

Abstract

The Ocellated Crake (Micropygia schomburgkii) is a poorly known species with a scattered distribution in Central and South America, linked to sites with tall grass vegetation in grasslands and savannas. The species was not previously known to occur in Argentina. We report on a population of Ocellated Crakes in the Campo San Juan protected area, southern Misiones province, Argentina, 365 km south from the nearest known occupied location in eastern Paraguay. We found 18 individuals in seven territories in this reserve in summer of 2020 and estimate a population of ~ 117 individuals in the reserve. The Ocellated Crake was detected in grassland on slopes and crests of rolling hills with dry, rocky soil with no nearby water. It was only found in grassland patches where cattle grazing was excluded for 6 years and where recent fires cleared successional shrubs and trees. It was not detected in grassland patches with absence of recent fires and presence of successional plants. We recommend active fire management with periodic burns in the reserve and additional searches for sites with Ocellated Crakes.