Constructing more informative plant-pollinator networks: visitation and pollen deposition networks in a heathland plant community.
Interaction networks are widely used as tools to understand plant-pollinator communities, and to examine potential threats to plant diversity and food security if the ecosystem service provided by pollinating animals declines. However, most networks to date are based on recording visits to flowers, rather than recording clearly defined effective pollination events. Here we provide the first networks that explicitly incorporate measures of pollinator effectiveness (PE) from pollen deposition on stigmas per visit, and pollinator importance (PI) as the product of PE and visit frequency. These more informative networks, here produced for a low diversity heathland habitat, reveal that plant-pollinator interactions are more specialized than shown in most previous studies. At the studied site, the specialization index [Formula: see text] was lower for the visitation network than the PE network, which was in turn lower than [Formula: see text] for the PI network. Our study shows that collecting PE data is feasible for community-level studies in low diversity communities and that including information about PE can change the structure of interaction networks. This could have important consequences for our understanding of threats to pollination systems.
School of Biological Sciences, University of St Andrews, Harold Mitchell Building, St Andrews KY16 9TH, UK gab32@st-andrews.ac.uk.
G
http://orcid.org/0000-0001-7494-0642
G
Ballantyne
School of Biological Sciences, University of Bristol, Life Sciences Building, Bristol BS8 1TQ, UK Cabot Institute, University of Bristol, Bristol BS8 1UJ, UK.
Katherine C R
http://orcid.org/0000-0001-6849-8747
KC
Baldock
School of Biological Sciences, University of St Andrews, Harold Mitchell Building, St Andrews KY16 9TH, UK.
P G
http://orcid.org/0000-0003-0631-0520
PG
Willmer
D000818:Animals; D001516:Bees / Q000502:physiology*; D003625:Data Collection; D004175:Diptera / Q000502:physiology*; D017753:Ecosystem; D004739:England; D029791:Ericaceae / Q000502:physiology*; D035264:Flowers / Q000502:physiology*; D011058:Pollen / Q000502:physiology; D054817:Pollination; D013045:Species Specificity; D039762:Ulex / Q000502:physiology*
network; pollination; pollinator effectiveness; pollinator importance; specialization; species interaction