Searching for the white fringeless orchid, Platanthera integrilabia, in western North Carolina

WCU Author/Contributor (non-WCU co-authors, if there are any, appear on document)
Maria "Mitzi" Harding (Creator)
Institution
Western Carolina University (WCU )
Web Site: http://library.wcu.edu/
Advisor
Katherine Mathews

Abstract: Rare species conservation has taken on an urgency in the face of unprecedented environmental degradation and biodiversity loss, and tools such as species distribution modeling are needed to increase the efficiency and efficacy of conservation efforts. Platanthera integrilabia (White Fringeless Orchid) is a rare orchid endemic to southern Appalachia and the surrounding area occupying a relatively narrow niche: non-alluvial sphagnum wetlands. The species was historically documented in North Carolina but has not been observed in the state since 1992. I hypothesized that some undiscovered populations may persist in western North Carolina in under-surveyed areas of suitable habitat. I used a weighted ensemble method to develop the first range-wide species distribution model (SDM) for P. integrilabia and performed targeted surveys based on model results. The SDM predicted approximately 6% of the species’ range to be suitable habitat, including approximately 3% (788km2) of the study area within western North Carolina (AUC-PR=0.991). Surveys did not yield any new occurrences of P. integrilabia, but seven of the 25 sites contained vestigial patches of suitable habitat, one of which is recommended for incorporation into the reintroduction efforts currently underway in Henderson County, NC. The results of this study do not rule out the possibility that P. integrilabia may still persist in North Carolina. Results do indicate that patches of suitable habitat still remain and can be predicted using a species distribution model. I also provide a framework for future iterations of the model intended to enhance the accuracy of predictions to more precisely direct future targeted surveys for P. integrilabia, and to aid in the conservation and restoration of this threatened orchid in its historical range.

Additional Information

Publication
Thesis
Language: English
Date: 2023
Keywords
ensemble SDMs, orchid conservation, Platanthera integrilabia, shagnum bogs, species distribution model
Subjects
Biogeography
Orchid populations
Platanthera
Peat mosses
Plant conservation

Email this document to