DEMOGRAPHY AND LIFE-HISTORY OF 3 SYMPATRIC SPECIES OF BOTRYCHIUM SUBGBOTRYCHIUM IN WATERTON-LAKES-NATIONAL-PARK, ALBERTA

We followed the fate of mapped sporophytes of Botrychium paradoxum, Bo trychium hesperium, and their hybrid Botrychium x watertonense in perm anent plots for 6 years in Waterton Lakes National Park, Alberta. All three species had half-lives of approximately 3 years or less. Botrych ium paradoxum had higher rates of recruitment and mortality leading to less stable population sizes than B. hesperium, perhaps contributing to the former's relative rarity. All species demonstrated prolonged do rmancy whereby plants remain below ground for 1 or more years before r eappearing. Surveys and monitoring studies for these and probably othe r species of Botrychium are more difficult owing to prolonged dormancy . Short lifespan and association with disturbed habitats suggests that these ferns may require natural disturbance regimes for long-term per sistence.