title: Effects of experimental seaweed deposition on lizard and ant predation in an island food web.
abstract: The effect of environmental change on ecosystems is mediated by species interactions. Environmental change may remove or add species and shift life-history events, altering which species interact at a given time. However, environmental change may also reconfigure multispecies interactions when both species composition and phenology remain intact. In a Caribbean island system, a major manifestation of environmental change is seaweed deposition, which has been linked to eutrophication, overfishing, and hurricanes. Here, we show in a whole-island field experiment that without seaweed two predators--lizards and ants--had a substantially greater-than-additive effect on herbivory. When seaweed was added to mimic deposition by hurricanes, no interactive predator effect occurred. Thus environmental change can substantially restructure food-web interactions, complicating efforts to predict anthropogenic changes in ecosystem processes.
authors.affiliation: Section of Evolution and Ecology and Center for Population Biology, One Shields Avenue, University of California Davis, Davis, CA 95616-8755, USA. jpioviascott@ucdavis.edu
authors.forename: Jonah
authors.initials: J
authors.lastname: Piovia-Scott
authors.forename: David A
authors.initials: DA
authors.lastname: Spiller
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Schoener
mesh_terms: D000818:Animals; D001000:Ants; D001181:Arthropods; D001444:Bahamas; D017753:Ecosystem; D005247:Feeding Behavior; D020387:Food Chain; D005843:Geography; D008116:Lizards; D010944:Plants; D011235:Predatory Behavior; D012621:Seasons; D012624:Seaweed