Current work

​

Pollinator Contribution Synthesis

 

Although 87% of plant species are pollinated by animals, we don't know exactly how important pollinators are for their reproduction because many plant species have some ability to self-fertilise without insects. To understand the potential impacts of pollinator declines on plant reproduction, we obtained data on the contribution of pollinators to plant reproduction from 1528 separate pollinator exclusion experiments, representing 1392 plant populations and 1174 species from 143 plant families across the world. Results will be published soon.

​

The consequences of pollination service for extinction risk via transient dynamics of population growth rate

Population growth rate depends both on demographic composition (the proportions of individuals in different ages or size groups) and the vital rates of those groups (survival, growth and reproduction). If vital rates remain stable, in the long term populations eventually reach stable demographic compositions with stable population growth rates. However, changes to the environment by humans can affect both the demographic composition and vital rates of populations. For instance, pollination services may be reduced due to declines in pollinators caused by humans, while the composition of populations may be altered by exploitation by humans or extreme climate events linked to climate change. This project aims to assess the importance of pollinators for the viability of plant populations affected by disturbance. To do this, we are investigating the consequences of changes in reproduction (for instance due to reduced pollination service) for population growth rate and risk of extinction for populations under transient dynamics (i.e. populations that are not at their long-term stable population growth rate and stage composition).

​

Mediation of Allee effects in pollination success by plant traits

​

In general, plants are pollinated better when they grow in larger, denser populations than in smaller or sparser ones. This means that plants growing at low abundance often suffer reduced seed production, an example of the Allee effect.  However, little is known about how plant traits mediate Allee effects. For instance, fitness may be more strongly reduced at low abundance in wind- than animal-pollinated plants because wind distributes pollen randomly, while animal pollinators move directly from flower to flower. I am using meta-analysis and mathematical modelling to assess how plant traits mediate Allee effects.

​

​