It Is Good to Be Eaten by a Bear: Effects of Ingestion on Seed Germination (Notes and Discussion) (Report‪)‬

INTRODUCTION Seed consumption by vertebrates can influence germination success of ingested seeds and thus has important consequences for plant reproduction and plant-frugivore interactions (Traveset, 1998). Throughout the Rocky Mountain region, grizzly bears (Ursus arctos) and black bears (U. americanus) rely heavily on fruits in late summer and early autumn (Welch et al., 1997). Fruit is an effective way for bears to increase fat reserves before entering torpor (Poelker and Hartwell, 1973; Bunnell and Hamilton, 1983; Eagle and Pelton, 1983), and fat reserves correlate with fecundity and offspring survival (Jonkel and Cowan, 1971; Rogers, 1976). Berries, when available, can comprise more than 90% of a bear's autumn diet (Grenfell and Brody, 1983; Raine and Kansas, 1990; Richardson, 1991). For example, in one day, a large bear in Banff National Park may consume as many as 70,000 individual fruits, defecate 7-10 times, with the average scat containing 10,000 seeds and move an average linear distance of 2.1 km within a home range of 149 [km.sup.2] (Hamer and Herrero, 1983). Thus, bears have the ability to influence the reproductive success of fruiting species if seeds remain viable after gut- passage.