Date of Award


Degree Type


Degree Name

Master of Science




Biology (MS)

First Advisor/Chairperson

Dr. Alan J. Rebertus


This is a study of the distribution, habitat characteristics, and reproductive demography of Calypso bulbosa and Cypripedium arietinum in the Grand Sable Dunes, Pictured Rocks National Lakeshore, Michigan, USA. Data for Cypripedium arietinum was collected from 345, 1-m radius plots in a stratified (by island) random sampling design. The total number of C. arietinum in 2009 was 3,596,000 (95% CI= 2,645,000-4,547,000). C. arietinum has several close vegetative associates, including Chimaphila umbellata and the moss Pleurozium schreberi. The population appears to be stable to expanding. Nearly 100 Calypso bulbosa were monitored in eight, 4 x 4-m permanent plots from 2008 to 2014. The minimum number of Calypso bulbosa in the Grand Sable Dunes was 321 plants in 2008; however, over the 6-year period (2008-2014) that number declined 40.5% with all plots pooled (mean=41.4%, SD=28.4, n=8 plots). The habitat models of Calypso show that it is strongly associated with several other orchids, and occurs primarily in moist swales. Climate change may have a tremendous impact on the Grand Sable Dunes and its plant communities. The long-term effects of climate change on these orchids and their associated mycorrhizae are unknown.

Access Type

Open Access

Included in

Botany Commons