Wednesday, August 4, 2010 - 2:10 PM

OOS 36-3: Discovering rare plant species ahead of climate change: What to do with the knowledge?

Alison E.L. Colwell and N. S. Nicholas. Yosemite National Park

Background/Question/Methods

Yosemite, set aside for preservation and public use in 1864, is celebrated for its botanical treasures and the dramatic topography that also plays a role in generating its unusual biodiversity. The park was well-documented biologically for its time early on, less so in latter half of the 20th century. In 2003, the National Park Service Inventory & Monitoring initiative provided funds to locate and document rare plant populations, and thus kindled ongoing efforts to document plant diversity. These efforts (weed early detection, surveys of unusual substrate rock and aquatic habitats) have increased the number of documented vascular plant species by 10%, to 1674 species. The startling lesson:  even in a heavily-visited location, our knowledge of this well-known group of organisms still remains incomplete. Bioinventory has recently been expanded to include bryophytes, lichens and freshwater algae. The lesson from these groups is reiterated:  biodiversity is similarly high, with startling range expansions, and discovery of tens of species previously unknown to science. This raises a concern:  approximately 10% of park vascular plant species (and presumably a similar proportion of the other groups) are rare, occurring in specialized habitats, or as isolated remnants from past climates, and are highly dependent on the stability of local water regimes. Because local climate change models predict decreasing snowpack and increasing average temperatures, many of these could be in peril. Plant communities are already changing in Yosemite, some shifting suddenly after large wildfires, some shifting steadily as conifers encroach on montane meadows. 

Results/Conclusions

This suggests two new approaches in our inventory efforts:  1) Future management strategies are likely to emphasize more aggressive methods to save species than the traditional preservation of the natural condition. Bioinventory efforts need to target gaps in the scientific knowledge that would inform decisions whether to aggressively manage species or not. Details on microhabitat, population sizes, pollinator interactions, seed viability, levels of seed predation, timing of seed set, seedling recruitment success – are types of information needed to assess transplantation or seed storage efforts.  2) Bioinventory efforts have a role to play in documenting this historic epoch as they may provide the last portrait of remote species or communities that cannot realistically be saved. A complete portrait requires a social context and therefore input from many perspectives besides that of the biologist. Therefore, contributions from professionals from other disciplines and from the public should be solicited as part of the bioinventory documentation.