title: Positive indirect interactions between neighboring plant species via a lizard pollinator.
abstract: In natural communities, species are embedded in networks of direct and indirect interactions. Most studies on indirect interactions have focused on how they affect predator-prey or competitive relationships. However, it is equally likely that indirect interactions play an important structuring role in mutualistic relationships in a natural community. We demonstrate experimentally that on a small spatial scale, dense thickets of endemic Pandanus plants have a strong positive trait-mediated indirect effect on the reproduction of the declining endemic Mauritian plant Trochetia blackburniana. This effect is mediated by the endemic gecko Phelsuma cepediana moving between Pandanus thickets, a preferred microhabitat, and nearby T. blackburniana plants, where it feeds on nectar and pollinates the plants. Our findings emphasize the importance of considering plant-animal interactions such as pollination at relatively small spatial scales in both basic ecological studies and applied conservation management.
authors.affiliation: Institute of Environmental Sciences, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland. dhansen@uwinst.unizh.ch
authors.forename: Dennis M
authors.initials: DM
authors.lastname: Hansen
authors.forename: Heine C
authors.initials: HC
authors.lastname: Kiesbüy
authors.forename: Carl G
authors.initials: CG
authors.lastname: Jones
authors.forename: Christine B
authors.initials: CB
authors.lastname: Müller
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D017753:Ecosystem; D005247:Feeding Behavior / Q000502:physiology; D008116:Lizards / Q000502:physiology*; D019660:Malvaceae / Q000502:physiology*; D008436:Mauritius; D019370:Observation; D031673:Pandanaceae / Q000502:physiology*; D011058:Pollen; D011157:Population Dynamics; D012098:Reproduction / Q000502:physiology; D013559:Symbiosis