Abstract
The proposed research will focus on the invasion and removal of exotic plants into wetland fens in New Jersey. Restoration of ecosystems invaded by non-native species may be difficult if the invasion has caused persistent changes in community or ecosystem functions. One little-studied pathway by which an invasive plant can alter community function is through its interactions with the pollinator community. Invasions by alien plants with copious, showy, insect-pollinated flowers can transform a landscape from poor to rich in floral resources. No data exist on the consequences of such invaders, or their removal, for pollinator populations and the native plants that rely on their services. I will examine the mechanisms underlying the impacts of purple loosestrife (Lythrum salicaria) invasions on native wetland fen plants as mediated through the pollinator community. I will use comparative and experimental approaches to document transient and persistent changes in reproductive patterns of pollinators and native plants caused by the invasion of purple loosestrife. In addition, I will study the extent to which they are reversed following experimental removals. I will focus on the reproductive performance of an array of bee and native plant species before and during the purple loosestrife bloom. Understanding the mechanisms of interaction between this invasive plant and the pollinator community will allow mitigation of potential negative impacts of purple loosestrife, as well as help predict undesired consequences of removal programs on native plant-pollinator mutualisms. I hope that this research will serve as a model for investigations and management of the effects of other invasive flowering plants on pollinator communities. The proposed research allows me to apply my experience with population and community ecology, pollination, and invasions to a novel issue in conservation. Insect conservation attracts little public or academic attention, although some services provided by insects are highly valued (e.g., pollination, food for game fish). To preserve these services, we must pay attention to plants, their insect mutualists, and features of their interactions that regulate their populations.