Fungal spores from coprolites, a means of detecting herbivore density.

Davis, O.K.
    Arizona-Nevada Academy of Science, & Department of Geosciences, University of Arizona, Tucson, AZ 85721-0077 USA,

During the historic period, spores of the dung fungus Sporormiella are abundant in lake and cave sediment where livestock are plentiful in the western United States. Sporormiella spores often exceed 50% of the upland pollen sum in samples from corral ponds and bed-grounds, and routinely reach 2-3% in lake and marsh samples in pastoral areas.

Sporormiella spores are comparatively rare during the Holocene, but they reach values of 2-4% in Pleistocene samples from lake sediments. Sporormiella spores are directly linked to extinct megaherbivores by their presence in mammoth dung from Bechan Cave, Utah. A precipitous decline of Sporormiella percentages after 10,800 yr B.P. apparently marks a decline of herbivore density in lake cores from Idaho, Colorado, and other sites in the western United States.