Could pine martens help control the invasive grey squirrel?

Cat checking one of 60 squirrel traps as part of her research (Photo: Nick Upton / naturepl.com)
Cat checking one of 60 squirrel traps as part of her research (Photo: Nick Upton / naturepl.com)

Cat McNicol is working on a PhD to improve our understanding of how pine martens may influence the behaviour of grey squirrels, and what this may mean for the impacts of grey squirrels on UK woodland.

Cat is working with Exeter University and the Vincent Wildlife Trust and is one of a number of PhD students we help support as part of our research programme.

We interviewed her to find out more about her research and how it could help our woods and wildlife.

What subject area is your PhD project on?

My PhD focuses on native species recovery as well as invasive species ecology and management. I therefore work primarily with the eastern grey squirrel, (Sciurus carolinensis) and the pine marten, (Martes martes).

What stage are you at in your PhD?

I am entering into the third year of my PhD.

Why did you apply for this PHD?

After living in Australia for a year, I became interested in the impacts of invasive species and their management. This project not only looks at how an invasive species behaves in the UK, but at a possible solution to contribute to its eradication. In combination with the recovery of a native UK mammal, this project was ideally suited to my research interests.

Woods provide vital habitat for thousands of species.

Learn more about our native wildlife

What do you hope to discover?

I hope to better understand the relationship between the grey squirrel and the pine marten as there are few places in the UK where their ranges overlap.  A previous study in Ireland has suggested that pine martens negatively affect grey squirrel populations, however we don't know if this is a unique or widespread relationship. The aim of my work is to study the interactions between these two species and the mechanisms underlying them.

What’s a typical day doing research for your PhD?

While I'm on fieldwork in Wales, I start work a few hours after sunrise. I have at least 60 squirrel traps to check. With each squirrel I catch I have to identify and record it. If it's a new individual, I put a GPS/VHF collar on it and microchip it so it can be identified when I catch it again. By the time I’ve finished this, I usually manage a short lunch break before I have to check all of the traps again before dark. However, once I have finished fieldwork I usually spend around 9 hours in the office in Cornwall analysing data and drinking excessive amounts of tea and coffee!

A previous study in Ireland has suggested that pine martens negatively affect grey squirrel populations (Photo: Alamy / WTML)
A previous study in Ireland has suggested that pine martens negatively affect grey squirrel populations (Photo: Alamy / WTML)

What’s the strangest thing you’ve had to do for your research so far?

Nothing seems strange if you do it often enough! I spend quite a lot of time collecting and processing pine marten poo and dead rodents which I use for pine marten diet analysis.

What made you want to do a PhD?

I’ve always wanted to be involved in conservation and have always valued evidence-based management. I really wanted to contribute well-rounded information and advice to practitioners which can actually inform conservation and ecosystem management. As a result, a PhD seemed like an ideal option during which I could carry out my own fieldwork but also could contribute to the bigger picture.

What’s your favourite biscuit for when you’re out and about doing field work?

I’m actually a big fan of oatcakes and peanut butter! Failing that, I’ll settle for a chocolate digestive.

How could the findings from your research help the Trust?

The species I work with, the grey squirrel, causes a huge amount of damage to native woodlands and the ecosystems they support. We have not only seen the decline of the red squirrel but also extensive bark stripping of trees, making them more vulnerable to disease.

The pine marten has been suggested as a potential ‘biological control agent’ for grey squirrels. I hope my research can aid our understanding of these two species so we can better direct grey squirrel management across the UK.

Woods provide vital habitat for thousands of species.

Learn more about our native wildlife