Research

My research addresses key problems related to global change, using a combination of advanced quantitative methods and field-based approaches. Currently, my research is mainly focused on biological invasions.

Specific questions I have been working on include:

1. What are the distributions of invasive tree pests and diseases in the UK, and what factors drive these distributions? Invasive tree pests and diseases - such as ash dieback, Phyotophthora, and the great spruce bark beetle - are a serious threat to natural woodland and commercial forestry in the UK. I am currently working on understanding the factors underlying these species’ distributions, and predicting their distributions both now and in the future.

2. How do invasive species affect animal behaviour, and what are the ecological consequences? Biological invasions are one of the greatest threats to ecosystems today, and the threat they pose is only likely to increase as species continue to be introduced across biogeographic barriers. However, until recently our understanding of invasive species’ impacts has been largely confined to the levels of populations and communities, and we lacked a synthetic understanding of impacts which occur at finer scales - including impacts on the behaviour of native animals. To address this problem, I have synthesised research on the impacts of invasive plants on animal behaviour within a novel mechanistic framework.
   
   To explore invasive species’ behavioural impacts in more detail, I have been examining a specific case study - the invasion of Laikipia County, Kenya, by prickly pear cacti (Opuntia spp.). I have been using camera traps to examine Opuntia’s effects on the occupancy and activity of key mammal species in the region. As part of this project, I created and managed Prickly Pear Project Kenya on the Zooniverse platform.
   
   I am particularly interested in understanding the mechanisms through which invasive species’ behavioural impacts occur. To this end, I have been applying insights and methods from the field of causal inference to the problem of modelling the patterns and drivers of species occupancy.

3. How will climate change restructure avian assemblages worldwide? Climate change will drive range-shifts in species, creating novel assemblages. However, we know very little about how these assemblages will be structured or function. By combining species distribution models with the AVONET dataset, which contains morphological trait data for every bird species in the world, we modelled how the functional diversity of avian assemblages is likely to shift due to climate change. We found that climate change change is likely to drive continental-scale shifts in avian functional diversity. These shifts have potentially important implications for the functioning of ecosystems in the future. This research has been covered by the European Commission’s Science for Environmental Policy news service.