Risks and Costs of Interactions between Plants and Hummingbirds

– Hummingbirds can act as mutualists by transporting pollen grains among flowers, but they may also act as vectors of several organisms which could affect the interaction with their plants. The transmission of such antagonists by hummingbirds searching for nectar rewards may end up in sexually transmitted diseases, pollen consumption and depletion of nectar rewards. Therefore, the supposedly harmonious, mutualistic interaction between plants and hummingbirds can be defeated by the transmission of antagonistic organisms along with pollen grains. The present paper is an attempt to contribute to this recent line of inquiry which focuses on the implications of third level species on the plant-hummingbird interaction. Accepted 5 January 2004. Keys words: Antagonists, hummingbird-plant interaction, flower mites, fungal pathogens, nectar thieves.