Monitoring and modelling beaver reintroductions: from eDNA to ecosystem impacts
Rewilding of ecosystems and reintroduction of Britain’s 'long lost' keystone species is a hot topic in applied ecology, and the release of beavers into our freshwaters, after being extinct since the 16th Century, is at the forefront of this movement.
However, the evidence base of the consequences for (re)inserting species into our human-modified landscape is alarmingly thin. There are plenty of examples in the ecological literature of unanticipated impacts where novel species have (re)invaded and caused major disruption and extensive rewiring of the food web, from rabbits in Australia to grey squirrels and the attendant declines in the native fauna.
Given that beavers have been absent from our shores for many centuries the recipient ecosystems contain a host of species that have effectively coexisted for hundreds of generations under potentially very different ecological rules: we know that in their current native range beavers are major ecosystem engineers, and that they can completely alter entire floodplains, reshaping the environmental templet within which all the other resident species operate.
The building of dams and the addition of a new large mammal to the freshwater food web could therefore have far-reaching implications that span many levels of biological organisation, from population dynamics of both the new and resident species, through to the functioning of the ecosystem as a whole.
In particular, the alteration of the river’s hydrology and habitat structure, as well as the resource base of the wider food web to one that is much more driven by detrital dynamics represents a major shift in how the ecosystem functions, which is largely unknown in the context of beaver reintroductions.
This project aims to take novel holistic approaches to quantify (and ultimately model and predict) how reintroductions of beavers to the UK could reshape the recipient systems: we will use a 'before-after-control-impact' case-study approach, whereby we use the National Trust beaver reintroduction in Valewood in Southern England as a natural experiment to track ecological responses in real time, combined with analysis of existing long-term large-scale data from other sites across the UK.
Part of this will also involve a detailed characterisation of the beaver’s role in both the terrestrial and freshwater food webs, by ecological and molecular characterisation of its functional impact as an ecosystem engineer and of its links to the wider food web.
This will give us unprecedented new insights into how this 'missing link' integrates into the established ecological network of many hundreds of other interacting species. At the other end of the ecological spectrum we will also measure how it alters key processes and overall ecosystem functioning – specifically through modification of the carbon cycle, as there is huge scope for this single species to alter the flux of greenhouse gases across the entire floodplain, indirectly via the microbiome
How to apply
Apply for this course through the Science and Solutions for a Changing Planet Doctoral Training Partnership website.
The deadline for applications is 4 January 2021.
This is a joint project between The Science and Solutions for a Changing Planet (SSCP) Doctoral Training Partnership at Imperial College London and The Natural History Museum.