Importance of life history studies for conservation of fragmented populations: A case study of the understory herb, Trillium camschatcense

Abstract

Trillium camschatcense is a common perennial woodland spring herb in Hokkaido, Japan. Anthropogenic land conversion (e.g. road construction and agricultural development) has resulted in a highly fragmented landscape with a large number of forest remnants and T. camschatcense is now often found in the understory of small remnant forests surrounded by pastureland or agricultural fields in the Hidaka region, Hokkaido. Accordingly, T. camschatcense in this region must have experienced dramatic changes in population size and spatial distribution, which may have significantly reduced seed production and genetic diversity. First, we summarize a series of life history studies on T. camschatcense. Second, we introduce approaches to understand the effects of forest fragmentation on the understory herb, T. camschatcense. Finally, we conclude that integration of data on demographic, reproductive biology and genetic approaches is essential for plant conservation, and we emphasize that it is important to have basic life history data, such as long-tem demographic data and variation in breeding system, on 'common species' before those species become 'new rares'. © 2006 The Authors.