A field guide to the biodiversity benefits of beavers

20/12/2018 in RZSS

Harris released in Knapdale, March 2018. Photo by Ben Harrower, Scottish Beavers

Photo 1: Harris released in Knapdale, March 2018. Photo by Ben Harrower, Scottish Beavers

It is a year to the day year since the Scottish Government signalled that   the statutory instrument to secure European Protected Species status for beavers in Scotland  would be laid in early 2018. So I feel disappointment that 2018 is almost at a close and their status has still not been clarified. Today we are calling on the First Minister to break the deadlock in Government, and finally set a firm date for giving beavers the protected status they need to thrive. You can find our letter here...

Since the approval of the trial reintroduction in 2008, the Royal Zoological Society of Scotland and the Scottish Wildlife Trust have been working together on gathering the scientific evidence base needed to support the decisions about the return of beaver to Scotland. We have also used the detailed knowledge gained during the Scottish Beaver Trial to work alongside a wide variety of partners to further the understanding of how beaver management should be best approached across the whole of Scotland into the future.

Here is a quick field-guide to some biodiversity benefits that beavers provide based on first-hand experiences that our Programme Manager, Ben Harrower, has had whilst walking the site of the Scottish Beaver Trial in 2018:

  1. Standing deadwood – the value of this is increasingly recognised for its important role in nutrient cycling and providing a slow release source of nitrogen. It also provides ideal habitat for a host of species from invertebrates through to owls and woodpeckers. If you visit the Dubh loch next to Loch Coille Bharr in Knapdale then you can see first-hand excellent examples of standing deadwood as a result of the beaver’s activities.

 Viewing the beaver influenced habitat at the Dubh loch from the boardwalk. Photo by B. Harrower, Scottish Beavers

Photo 2: Viewing the beaver influenced habitat at the Dubh loch from the boardwalk. Photo by B. Harrower, Scottish Beavers.

 

  1. Shallow flooding/dam creation – one of the most impressive features of beaver activity is the ability to modify water levels within a given water body. When the water level is increased, this often creates shallow flooding around the banks of the loch providing more opportunities for species like toads, frogs and invertebrates. An increase in toad numbers has been witnessed on the Lily loch in Knapdale where, during the month of September, thousands of toadlets can be seen leaving the shallow edges of the loch, thanks to the beavers.

 Common toad on the edge of Lily loch. Photo by Ben Harrower, Scottish Beavers

Photo 3: Common toad on the edge of Lily loch. Photo by Ben Harrower, Scottish Beavers

 Impressive dam at the Lily loch which provides the shallow flooding around the waters edge. Photo by Scottish Beavers

Photo 4: Impressive dam at the Lily loch which provides the shallow flooding around the waters edge. Photo by Scottish Beavers

 

  1. Coppicing – one of the most visual effects beavers can have on the environment is the felling of trees. Often this appears dramatic, especially in the winter when there is no foliage. However, where trees have been removed, new coppice will take its place.

This promotes vigorous re-growth and beavers’ gnawing activities instigate the fresh growth of many smaller shoots. These bushy scrub-like replacements provide excellent habitat for birds such as willow warblers, blackcaps and wrens.

 New growth of Rowan following beaver felling activity at Loch Coille Bharr, this will become shrub-like in years to come. Photo by Ben Harrower, Scottish Beavers

Photo 5: New growth of Rowan following beaver felling activity at Loch Coille Bharr, this will become shrub-like in years to come. Photo by Ben Harrower, Scottish Beavers

 

All parties recognise that there can be challenges to beaver presence, but we should also never forget the benefits that these incredible eco-system engineers provide. Beavers can stabilise river flows to reduce flood risk and create valuable woodland coppice and wetland habitats in which a wide range of other species can flourish. In the end, we need to re-learn to live with a species that used to be our neighbour.

 

Read our open letter to the First Minister

 

Dr Helen Senn, RZSS Head of Conservation and Science

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