Naturwissenschaften

, Volume 96, Issue 3, pp 339–346

Indirect interactions between invasive and native plants via pollinators

Authors

    • Institute of Environmental SciencesUniversity of Zurich
    • Ecosystem Management, Institute of Terrestrial EcosystemsSwiss Federal Institute of Technology (ETH) Zurich
  • Christine B. Müller
    • Institute of Environmental SciencesUniversity of Zurich
Original Paper

DOI: 10.1007/s00114-008-0481-x

Cite this article as:
Kaiser-Bunbury, C.N. & Müller, C.B. Naturwissenschaften (2009) 96: 339. doi:10.1007/s00114-008-0481-x

Abstract

In generalised pollination systems, the presence of alien plant species may change the foraging behaviour of pollinators on native plant species, which could result in reduced reproductive success of native plant species. We tested this idea of indirect interactions on a small spatial and temporal scale in a field study in Mauritius, where the invasive strawberry guava, Psidium cattleianum, provides additional floral resources for insect pollinators. We predicted that the presence of flowering guava would indirectly and negatively affect the reproductive success of the endemic plant Bertiera zaluzania, which has similar flowers, by diverting shared pollinators. We removed P. cattleianum flowers within a 5-m radius from around half the B. zaluzania target plants (treatment) and left P. cattleianum flowers intact around the other half (control). By far, the most abundant and shared pollinator was the introduced honey bee, Apis mellifera, but its visitation rates to treatment and control plants were similar. Likewise, fruit and seed set and fruit size and weight of B. zaluzania were not influenced by the presence of P. cattleianum flowers. Although other studies have shown small-scale effects of alien plant species on neighbouring natives, we found no evidence for such negative indirect interactions in our system. The dominance of introduced, established A. mellifera indicates their replacement of native insect flower visitors and their function as pollinators of native plant species. However, the pollination effectiveness of A. mellifera in comparison to native pollinators is unknown.

Keywords

Apis melliferaBertiera zaluzaniaInvasive plantIndirect interactionPlant reproductive successPsidium cattleianum

Copyright information

© Springer-Verlag 2008