Analysis of Clapper Rail Habitat Suitability in Coastal Louisiana

Katelyn Mall
Tanna Dartlon
Brian Roberts
Heidi Adams

Description

The Clapper Rail is a marsh bird that nests in tidally influenced wetlands of coastal Louisiana, especially those with established emergent vegetation. These habitat characteristics have been used to develop a habitat suitability index (HSI) model for the rail. Based on preliminary data collected near Cocodrie, Louisiana in August 2019, however, we hypothesized this HSI model did not fully explain nesting habitat suitability for the Rail. Thus, we conducted meta-analyses of the 2019 data to evaluate the influence of other habitat variables on Clapper Rail nesting habitat suitability. These variables the distance from the water’s edge and the elevation at which the Clapper Rail is most likely to have a high rate of nest success. Results of our meta-analyses indicate percentage of edge habitat from tidally influenced water is a significant factor to Clapper Rail habitat. Percentage of emergent wetland vegetation may also be affected by the area’s elevation, according to species. Distichlis spicata had very little distribution, with observed plant growth occurring above sea level. Juncus roemerianus showed similar growth patterns, with >10 plants observed below sea level. Spartina alterniflora is the most widely distributed of the three species, with plants observed at high levels across the elevation range. Future objectives of our research include gathering further Clapper Rail nest site locations and activity to confirm the possible adjustments to the habitat suitability model for Clapper Rails in Louisiana marshes.

 

Analysis of Clapper Rail Habitat Suitability in Coastal Louisiana

Online

The Clapper Rail is a marsh bird that nests in tidally influenced wetlands of coastal Louisiana, especially those with established emergent vegetation. These habitat characteristics have been used to develop a habitat suitability index (HSI) model for the rail. Based on preliminary data collected near Cocodrie, Louisiana in August 2019, however, we hypothesized this HSI model did not fully explain nesting habitat suitability for the Rail. Thus, we conducted meta-analyses of the 2019 data to evaluate the influence of other habitat variables on Clapper Rail nesting habitat suitability. These variables the distance from the water’s edge and the elevation at which the Clapper Rail is most likely to have a high rate of nest success. Results of our meta-analyses indicate percentage of edge habitat from tidally influenced water is a significant factor to Clapper Rail habitat. Percentage of emergent wetland vegetation may also be affected by the area’s elevation, according to species. Distichlis spicata had very little distribution, with observed plant growth occurring above sea level. Juncus roemerianus showed similar growth patterns, with >10 plants observed below sea level. Spartina alterniflora is the most widely distributed of the three species, with plants observed at high levels across the elevation range. Future objectives of our research include gathering further Clapper Rail nest site locations and activity to confirm the possible adjustments to the habitat suitability model for Clapper Rails in Louisiana marshes.