I D E A S A N D P E R S P E C T I V E S Pollinators as mediators of top-down effects on plants

Kenwyn B. Suttle Department of Integrative Biology, University of California, Berkeley, CA 94720-3140, USA Correspondence: E-mail: [email protected] Abstract This paper explores the idea that predators may disrupt plant–pollinator relationships and consequently inhibit reproduction in flowering plants. Amidst growing evidence that predators influence plant–pollinator interactions, I suggest that such pollinator-mediated indirect effects may be a common feature of terrestrial communities, with implications for research into top-down effects and pollination ecology. Experimental evidence of such an effect from a riparian system in northern California is provided, where crab spiders decreased seed production in inflorescences of the invasive plant Leucanthemum vulgare by reducing the frequency and duration of floral visits by pollinating insects.