LIFE HISTORY TRADE-OFFS IN A RARE ORCHID: THE COSTS OF FLOWERING, DORMANCY, AND SPROUTING

Abstract

We tested for life history trade-offs among dormancy, sprouting, and flowering in a seven-year study of a threatened, perennial plant, the small yellow lady's slipper orchid (Cypripedium calceolus ssp. parviflorum (Salisb.) Fernald). The aboveground states of 629 genets were monitored over seven years in a wet meadow in northeastern Illinois, USA. With mark–recapture statistics, survival, resighting, and stage transitions were calculated among three stage classes of individuals: dormant, vegetative, and flowering. The best-fit and most parsimonious models suggested that (1) survival was constant among years, but varied by stage; (2) dormant individuals suffered significantly higher mortality and were more likely to become dormant in future years than sprouting or flowering individuals; (3) flowering individuals had significantly higher survival and were more likely to flower in the future than sprouting and dormant individuals; and (4) sprouting individuals had a significantly higher stage transition to d...