Skip to content

This repository contains data and analysis from a 2022 regional survey conducted in coastal North Carolina and Virginia. The primary focus was modeling the abundance and occupancy of a threatened bird species in these areas using R.

License

Notifications You must be signed in to change notification settings

gausec/OccupancyModeling

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

King Rail Occupancy and Abundance in Coastal North Carolina and Virginia


Aim

I am interested in king rail occupancy and abundance in regions surrounding a source population at Mackay Island National Wildlife Refuge.


Repo Contents

  • Analyses: subdirectories containing markdown files with analysis steps in R.
  • Bin: R script by Carol Gause.

Contributor


Funding Sources

Grant funding for this project was generously awarded by The Garden Club of America, The Carolina Bird Club, and The Association of Field Ornithologists.


Thank you

Thank you to my hard-working technicians who diligently assisted with data collection in the field:

  • Megan Linke
  • Abby Bourne
  • Nic Main

Natural history & background

The king rail is a very secretive, freshwater marsh bird. While it is chicken-sized, it is very hard to see due to the dense emergent vegetation it inhabits. As you might imagine, this makes these rails very difficult to study. For this reason, we don't know as much about king rails as we do about easier-to-study species. It is really important to study these birds as they are indicators of freshwater marsh ecosystem health. They are sensitive to environmental changes, and their populations have been declining for over half a century. The king rail is listed as federally endangered in Canada and as threatened or endangered by 12 states in the United States.

In the United States, the distribution of the king rail has become concentrated along the east coast. This is a result of inland freshwater marshes vanishing due to land-use changes and habitat degradation. This has led to the remaining freshwater marshes in the southeast becoming the primary habitat for these birds. However, populations along the east coast face their own challenges: climate change has led to sea-level rise and increased occurrences of intense storms resulting in saltwater intrusion. This change in habitat conditions renders these areas unsuitable for the king rail. The clapper rail, which is tolerant of saltwater, often out-competes the king rail in brackish habitats. Additionally, the presence of the invasive plant Phragmites australis in both inland and coastal marshes further complicates the situation. King rails can tolerate this plant but have not been observed nesting in it.

For these reasons, it is becoming increasingly urgent to learn more about this species.


Survey area

Survey area


Note: Actual map of survey points, areas of interest, and results will not be posted here until results are published.

About

This repository contains data and analysis from a 2022 regional survey conducted in coastal North Carolina and Virginia. The primary focus was modeling the abundance and occupancy of a threatened bird species in these areas using R.

Topics

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Languages