Tuesday, August 4, 2009 - 10:30 AM

SYMP 6-7: Restoration ecology and plant-pollinator networks

Jane Memmott, University of Bristol


When human activities damage ecosystems it may be possible to repair the damage through ecological restoration.  In planning and evaluating restoration projects, it is critical to also consider function; what constituent species do rather than just whether they are present or not.  Pollination of flowering plants by animals is a critical mutualistic ecological interaction of natural and managed ecosystems that cannot feasibly be replaced by technology.  The majority of interactions between plants and their flower visitors are embedded in a complex web of interactions which can be studied in the manner of conventional food webs.   The interactions between species can provide a valuable metric when comparing restored and reference sites as reproductive mutualisms, such as pollination and seed dispersal, characterize the subtle, complex web of interactions, which, if broken by human actions, could cause a cascade of extinctions.


This talk will consider three restoration programmes which have specifically addressed plant-pollinator interactions: 1) The restoration of heathland pollinators and the restoration of the parasites of these pollinators.  Higher trophic level species such as parasites, parasitoids and pathogens are frequently ingored in community studies, despite playing key roles in the structure, function and food web stability of ecological communities.  Pollinators such as bees support particularly rich communities of parasites, parasitoids and pathogens and they can make good metrics of restoration success.  2) Removal of alien plants is an important part of many conservation programmes and while this is widely expected to have a positive on native species, a negative effect is also possible.  For example, in the restoration of the Avon Gorge, UK removing aliens could remove an important food supply of the native pollinators with potentially detrimental effects on one of the focal native plants.   3) The restoration of plant pollinator interactions in Scottish pine forest understory.  Here an ambitious experimental design (6 replicates of 5 different successional stages) has enabled the landscape level consequences of restoration of pollinators to be considered in a managed forestry ecosystem.