Availability, use and selection of major food items (>1% of the diet) consumed by lemmings in winter.

Availability is based on biomass of vascular plants and mosses sampled in stream gullies and mesic tundra in August 2010, at peak growth (n = 16 plots). Both availability and use are presented as proportions. Selection was analyzed separately for vascular plants and mosses and availability and use sum to 1 within each of these taxonomic groups (0 = no selection, + = positive selection, − = negative selection; based on 95% confidence interval; signs in parenthesis indicates selection ratio based on 90% confidence interval).
1 Ericaceae, which accounted for 58% of all vascular plant biomass, was excluded because it was not consumed by either lemming species.
2 Selection could not be calculated for Bryaceae, Grimmiaceae and Timmiaceae because these plants were not found that year in our availability sampling plots.
3 Other important moss families present at the site and not consumed by lemmings include Scapaniaceae (availability = 0.228), Amblystegiaceae (0.195), Hylocomiaceae (0.193), Ptilidiaceae (0.043) and Ditrichaceae (0.019).
Availability, use and selection of major food items (>1% of the diet) consumed by lemmings in winter.