Status and Habitat Relationships of the Black Rail (Laterallus jamaicensis) in Coastal Louisiana, USA

Abstract

The Eastern Black Rail (Laterallus jamaicensis jamaicensis) is a conservation priority species, yet distributional and habitat data continue to be lacking. In Louisiana, USA, the species is known from 13 documented records and scattered anecdotal reports. From May 2017 to April 2019, we conducted Louisiana's first systematic survey using point count and drag-line techniques. During breeding and non-breeding point counts, we detected one or more Black Rails during 3.1% (n = 1,239) of surveys across 13.8% (n = 152) of point locations at 33.3% (n = 33) of sites. Detection probability was highest from March to May (0.245 ± 0.055 SE) and occupancy was best explained by increasing Gulf cordgrass (Spartina spartinae) cover. During non-breeding season drag-line surveys, we tallied 36 detections at 43.8% (n = 16) of sites. We deployed VHF radios on 13 Black Rails between December 2018 and March 2019 and estimated a home range of 0.71 (± 0.13 SE) ha. These surveys provided the first evidence of a year-round Black Rail population in Louisiana. Additional study is urgently needed to understand habitat management needs, including prescribed fire, mechanical shrub removal, and cattle (Bos taurus) grazing intensities. Meanwhile, aggressive conservation actions are needed to preserve remaining habitat.