If you’ve been following the blog you will have seen us getting excited about a few nibbled sticks on Loch Lomond NNR last summer. In early August our summer placement Blyth spotted a suspiciously chiselled willow branch in the water, and after setting up a trail camera we caught the culprit on film – a beaver! Since then I have been working on a project to find out more about these elusive animals on the reserve with the help of RSPB volunteers.
Beavers have been absent from Scotland for over 500 years after being hunted to extinction for their fur pelts and castoreum, a secretion from their castor glands believed to have medicinal properties and used in some perfumes (yup, seriously!). Following a successful re-introduction, beaver numbers are now increasing and on the 1st of May 2019 beavers gained legal protection in Scotland. Scottish beavers are expanding their range naturally and there are now territories throughout the Tay and Forth catchments.
Loch Lomond NNR is the first National Nature Reserve in Scotland to host beavers and we wanted to find out more about them to share this information with visitors. The first step to learning more about Eurasian beaver ecology was to spend time with some beaver experts! In December I was lucky enough to visit a beaver territory with Neil Mitchell, the Scottish Beaver Mitigation Scheme Liaison Officer, and Róisín Campbell-Palmer, an environmental consultant with years of experience in beaver re-introduction and mitigation schemes. We visited a site where a family group had established a territory fairly recently.
I’d never seen an area colonised by a beaver family before and I was shocked by what I saw. Beavers have a reputation for being ‘busy’ and are often referred to as ‘ecosystem engineers’. This is because they alter wetland habitats through damming streams, building lodges, digging burrows and felling trees. This behaviour is great for biodiversity and provides a natural solution to flooding. However, in some areas their activities can look messy and cause problems, creating conflicts with land managers and upsetting members of the public.
At this particular site, the beavers had cut down many trees, consuming the bark and woody vegetation and using the branches to build several dams along a small stream. They do this to manage water levels as they feel safer moving through deep water to reach their lodge or burrow entrance rather than travelling overland. At this site, the pond was naturally quite shallow and so the beavers had been busy damming to raise the water level. The family had also built a large lodge from compacted mud and branches.
Over time the beaver activity at this site will become much less obvious as they have only recently established a territory. If you take a visit to Knapdale Forest, the site of the Scottish Beaver Trial, now 11 years on from their release there is little noticeable evidence of beavers living there.
It was fascinating to see what these animals are capable of and I got a good idea of the kinds of signs to look out for at Loch Lomond NNR.
The river Endrick is a very different kind of watercourse to the family site I visited. The river is much deeper, wider and slower-moving and the sandy banks provide an excellent place for beavers to dig into and excavate burrows and canals. Also there is much more room to roam with the potential to travel into the loch itself. This meant that signs of beaver activity were going to be less obvious and potentially tricky to spot, especially if there is only one individual moving through a large area.
In early spring, I began conducting weekly beaver surveys along the river Endrick on Loch Lomond NNR, placing trail cameras where I found signs of beaver activity. These surveys have now come to an abrupt end due to COVID-19 quarantine measures but I will be sharing what I have learned about beaver ecology, and more importantly what I have found out about the beavers on the reserve, in a series of blogs over the coming weeks. So keep checking the blog for beaver updates, including some cute beaver photos and videos!