title: Pollination services enhanced with urbanization despite increasing pollinator parasitism.
abstract: Animal-mediated pollination is required for the reproduction of the majority of angiosperms, and pollinators are therefore essential for ecosystem functioning and the economy. Two major threats to insect pollinators are anthropogenic land-use change and the spread of pathogens, whose effects may interact to impact pollination. Here, we investigated the relative effects on the ecosystem service of pollination of (i) land-use change brought on by agriculture and urbanization as well as (ii) the prevalence of pollinator parasites, using experimental insect pollinator-dependent plant species in natural pollinator communities. We found that pollinator habitat (i.e. availability of nesting resources for ground-nesting bees and local flower richness) was strongly related to flower visitation rates at the local scale and indirectly influenced plant pollination success. At the landscape scale, pollination was positively related to urbanization, both directly and indirectly via elevated visitation rates. Bumblebees were the most abundant pollinator group visiting experimental flowers. Prevalence of trypanosomatids, such as the common bumblebee parasite Crithidia bombi, was higher in urban compared with agricultural areas, a relationship which was mediated through higher Bombus abundance. Yet, we did not find any top-down, negative effects of bumblebee parasitism on pollination. We conclude that urban areas can be places of high transmission of both pollen and pathogens.
authors.affiliation: General Zoology, Institute for Biology, Martin Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany Department of Community Ecology, Helmholtz Centre for Environmental Research-UFZ Halle, Theodor-Lieser-Strasse 4, 06120 Halle, Germany panatheod@gmail.com.
authors.forename: Panagiotis
authors.identifier: 0000-0002-4056-5300
authors.initials: P
authors.lastname: Theodorou
authors.affiliation: General Zoology, Institute for Biology, Martin Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany Molecular Evolution and Animal Systematics, Institute of Biology, University of Leipzig, Talstrasse 33, 04103 Leipzig, Germany ESCALATE, Department of Computational Landscape Ecology, Helmholtz Centre for Environmental Research-UFZ Leipzig, Permoserstrasse 15, 04318 Leipzig, Germany Department of Zoology, Faculty of Natural Sciences, Vilnius University, M.K. Čiurlionio 21/27, 03101 Vilnius, Lithuania.
authors.forename: Rita
authors.initials: R
authors.lastname: Radzevičiūtė
authors.affiliation: German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany Department of Community Ecology, Helmholtz Centre for Environmental Research-UFZ Halle, Theodor-Lieser-Strasse 4, 06120 Halle, Germany.
authors.forename: Josef
authors.identifier: 0000-0002-8624-4983
authors.initials: J
authors.lastname: Settele
authors.affiliation: Department of Community Ecology, Helmholtz Centre for Environmental Research-UFZ Halle, Theodor-Lieser-Strasse 4, 06120 Halle, Germany.
authors.forename: Oliver
authors.identifier: 0000-0001-8779-2335
authors.initials: O
authors.lastname: Schweiger
authors.affiliation: General Zoology, Institute for Biology, Martin Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany National Biodiversity Data Centre, Beechfield House, WIT West Campus, Waterford, Co., Waterford, Ireland.
authors.forename: Tomás E
authors.initials: TE
authors.lastname: Murray
authors.affiliation: General Zoology, Institute for Biology, Martin Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany.
authors.forename: Robert J
authors.identifier: 0000-0003-2517-1351
authors.initials: RJ
authors.lastname: Paxton
mesh_terms: D000818:Animals; D001516:Bees / Q000469:parasitology* / Q000502:physiology*; D003421:Crithidia; D017753:Ecosystem; D035264:Flowers; D054817:Pollination; D014507:Urbanization
keywords: Bombus; Crithidia bombi; Nosema bombi; land-use change; local habitat; plant–animal interactions