Spalding's campion (Silene spaldingii) COSEWIC assessment and status report: chapter 8

Limiting Factors and Threats

Habitat loss has historically presented the greatest threat to Silene spaldingii and most of the Palouse prairie habitat suitable for agricultural or urban development has already been lost. The British Columbia population is located on private property near a small town, and future development could destroy some, or all, of its present area of occupancy. Habitat loss has also resulted in a fragmented distribution in the U.S.A., making loss of genetic variation a concern for the British Columbia population.

Another significant threat is agricultural activities, including grazing. The habitat of the British Columbia population appears to be suffering from prior overgrazing. The remaining S. spaldingii habitat is increasingly affected by invasion of non-native species. The plants in the British Columbia population occur in a disturbed grassland, with a significant cover of Bromus tectorum, as well as Hypericum perforatum. Both of these invasive species compete directly with S. spaldingii.

Fire suppression is likely occurring on the Tobacco Plains, resulting in reduced recruitment of S. spaldingii, and allowing in-growth of woody vegetation. In addition, drought conditions over the past few years is likely increasing stress on the plants, intensifying anthropogenic pressures.

Page details

Date modified: