Monitoring Tobias' saxifrage (Saxifraga bryophora var. tobiasiae) on the Payette National Forest: 2007 results

Publication Type:

Unpublished

Source:

Mancuso Botanical Services, Boise, Idaho, p.37 pp. plus appendices (2008)

Call Number:

U08MAN01IDUS

Abstract:

Tobias’ saxifrage (Saxifraga bryophora var. tobiasiae) is a Forest Service Region 4 sensitive plant species endemic to the mountains north of McCall in west-central Idaho. All seven known occurrences are located on the Payette National Forest. A monitoring program was initiated for Tobias’ saxifrage in 2001 to provide population, habitat, and threat trend information to help the Payette National Forest plan and manage for the species’ long-term conservation. The monitoring protocol includes collecting Tobias’ saxifrage census, ground disturbance, and plant community information, and taking photo point photographs. Plots were resampled in 2002 and 2003, and again in 2007. This report summarizes monitoring results for 2007 and makes comparisons to the 2001-2003 baseline dataset. <br> Tobias’ saxifrage density in 2007 was less than the baseline mean for all occurrences except Hazard Lake. Reductions in plant density were statistically significant at the North Fork Pearl Creek, Slab Butte, and Granite Mountain occurrences. Combining all occurrences, rangewide Tobias’ saxifrage density was significantly less in 2007 compared to the baseline mean. However, it is premature to say Tobias’ saxifrage has a downward trend at either the occurrence or rangewide scale because the three-year baseline dataset showed annual fluctuations in plant abundance to likely be a natural part of the species’ demography. Cattle and recreation-related disturbances have been limited to the Granite Mountain occurrence, and 2007 levels showed no significant change compared to baseline values. In 2007, the only individual disturbance factors to significantly increase were pocket gopher activity at the Fisher Creek Saddle occurrence, and disturbance of unknown cause at Beaverdam Peak South. In addition, rangewide total ground disturbance increased significantly compared to the baseline mean. Monitoring detected no change in plant community composition or species abundance at any Tobias’ saxifrage occurrence. A continued commitment to monitoring is needed to understand trends for Tobias’ saxifrage and ensure land managers receive relevant and timely information regarding the status of the species and its habitat.