Introduced herbivores and the Allee effect in animal- pollinated plants

Interspecific interactions can be modulated by the community context in which they occur. In this paper I focus on plant–pollinator interactions and their modulation by introduced herbivores through changes in plant population density. I first develop a mathematical model that relates the population density of an animal-pollinated plant species with pollinator visitation frequency, pollination, reproduction and per capita growth rate. This model allows me to investigate how several pollination-related parameters—including relative abundance of the focal plant species, pollinator specialization, pollination quantity and quality and pollen limitation of reproduction—influence the relationship between per capita growth rate and population density. I then use this theoretical framework to discuss two case studies that have addressed the densitymediated effects of introduced herbivores on plant reproduction. This exercise allows me to point out several limitations of previous studies and to suggest avenues for future research. [