Effects of Invasive Non-Native Species within ecological networks and consequences for ecosystem function

Invasive Non-Native Species (INNS) are considered a major driver of biodiversity
loss. There is increasing empirical evidence of the direct and indirect effects of
invasive non-native species on biodiversity but the scale of such studies is often
limited. We propose to extend invasion models to encompass ecological networks
and explore the hypothesis that invasive non-native species weaken the strength of
interactions within ecological networks with negative consequences for ecosystem
function. Most studies on the impacts of invasions focus on the impacts of one
species on another and are limited to the population-level, thereby avoiding the
complexities of a community approach whereby assemblages of species would be
included. Oversimplified studies could result in misleading conclusions because of
the importance of positive and negative feedback mechanisms, for example those
mediated by parasites, throughout communities and consequently resultant effects
on the functions they deliver. There is considerable scope to improve understanding
by taking a network approach to unravelling impacts of invasive non-native species
and so enhance predictions of impact and community resilience so informing
decision-making tools such as risk assessments.
Using modelling approaches to explore ecological networks the student will address
questions including:
In what ways do the strength of interactions change within ecological networks
including invasive non-native species?
How do such changes effect ecosystem function?
What is the relevance to ecosystem services approaches and Nature's
Contributions to People (as defined by the Intergovernmental Science-Policy
Platform on Biodiversity and Ecosystem Services)?


The student will work alongside ecologists with expertise in compiling and analysing
large datasets within the Centre for Ecology & Hydrology and the University of
Stirling. The Non-Native Species Secretariat will provide policy and communication
context. The student will have access to large-scale and long-term datasets on
invasive non-native species alongside long-term monitoring time series from across
the globe for terrestrial and freshwater systems and other relevant data layers
(including climate and land-use) to explore interactions among drivers of change.
The student will build a database of ecological interactions using life-history traits
and occurrence datasets to underpin analysis on ecological networks to explore
effects of invasive non-native species on ecosystem function and resilience.
The studentship, although within the Biodiversity Science Area, will span other
science areas including Hydro-Climate Risks. This project will develop and apply
analytical techniques to address NERC goals of understanding and predicting how
our planet works and managing our environment responsibly.