A bonanza-blank pollinator reward schedule in Delphinium nelsonii (Ranunculaceae).

Data indicate a non-random distribution of nectar among plants in a population of Delphinium nelsonii Greene. More plants than expected had no nectar (blanks) or large amounts of nectar (bonanzas), while fewer plants than expected had intermediate amounts of nectar. This bonanza-blank pollinator reward schedule suggests that a high proportion of the nectar obtained by pollinators comes from occasional bonanza plants encountered in the population.