20 May, 2014

Relative floral density of an invasive plant affects pollinator foraging behaviour on a native plant

by Amy M. Iler & Karen Goodell

Flowers of Amur honeysuckle, an invasive plant species in Eastern North America.
Invasive plants act like weeds, overtaking natural ecosystems.  In addition to crowding out native plants, invasive plants can also steal pollinators from them.  Alternatively, the showy floral displays of invasive plants have also been shown to attract pollinators that spill over onto native plants, thus benefiting native plant pollination.
Here we created artificial arrays of native and invasive flowers to test the idea that relative floral densities may explain why invasive plants can have both negative and positive effects on native plant pollination.  We studied the invasive plant Amur honeysuckle (Lonicera maackii) and the native plant wild geranium (Geranium maculatum).  

Read the whole summary in: English!
Read the scientific publication in JPE.

09 May, 2014

Spring foraging in dune ecosystems

by Aoife O’Rourke, Úna Fitzpatrick and Jane Stout

Queen bumblebees foraging on male creeping willow catkins
In this study the visitation rates of bumblebees, solitary bees and hoverflies to a variety of spring flowering plants, typical of fixed dune habitat, were investigated. The sugar composition of the nectar of each plant was examined, as was the relative abundance of essential amino acids in the pollen of the study plants, and the total abundance of floral units. These measurements were then related to insect visitation rates. 

Read the whole summary in: English!
Read the scientific publication in JPE.