Why did the squirrel cross the road?

A researcher from the University of Leeds’ Faculty of Biological Sciences conducted a survey to discover whether red squirrels living in Loch Lomond and the Trossachs National Park were using rope bridges installed by a local wildlife group.

This kind of bridge is usually installed at sites where there have been fatalities recorded but up until now no-one has collected any data to show whether or not they are actually used by the animals.

Stephen Lockwood, who is completing a masters’ degree in biodiversity and conservation, took specialist training in tree climbing so that he could to set up equipment to record the squirrels’ movements. In addition to using cameras he also used tubes filled with nuts and sticky tape to gather hairs and clay moulds to record the animals’ footprints.

He says: “This isn’t just about cutting down on the number of squirrels killed on the roads. We also know that when a natural habitat becomes fragmented, such as by the introduction of unnatural barriers like roads, there is a lesser chance of the species surviving in the long term because the opportunities for breeding are fewer. The bridges hopefully encourage the squirrels to explore a wider area and therefore lessen the chance of inbreeding. By finding out whether they actually use these bridges we can assess how useful it is to install them.”

Ruhi Thallon, from the Cowal Red Squirrel Group, which commissioned the survey, says: “An SNH grant for rope bridges was successfully applied for by the local community of Strachur and two have been erected across the main road there but we needed to find out how cost-effective they were before spending any more money putting them up at other sites. When we looked into it we were surprised to discover that no one has ever really tested the efficiency of these bridges. The research that Stephen from the University of Leeds has now carried out should help us make our case when we apply for funding for future projects.”

Having analysed his findings, Stephen has now concluded that the creatures are definitely using the bridges, but that it is important to put them in the right place. He says, “In areas where there is a high population of squirrels then the new bridges we put up were being used within a couple of days, not surprisingly we also found that baiting the bridges with food also encouraged the squirrels to use them. This kind of information has never been collected before and it could now be used by other wildlife conservation groups or even by developers when considering plans for new road-building projects that cut through squirrel habitat.”

David Blakeley, from the Institute of Integrative and Comparative Biology at the University of Leeds, feels this has been a very worthwhile project: “Our Masters programme in Biodiversity and Conservation provides us with an opportunity to conduct the kind of research that could have a real impact on British wildlife, this project is just one example.”