Looking after the River Mimram

August 19, 2021

As the summer draws on we have been experiencing the varied great British summertime weather at its best! Panshanger Park is still staying busy through the summer and the free ‘Life at the Lake’ family events are taking place every Tuesday through August. These provide an opportunity to discover what lives beneath the surface of the lakes at Panshanger! Find us by Riverside lake in the centre of the site. For more information on these events please go to hertswildlifetrust.org.uk/events.

Also, a stretch of the river Mimram within the park is being treated to improvement works this summer with some naturalistic felling being undertaken in partnership with the Wild Trout Trust, the Panshanger Anglers and Maydencroft Limited. Naturalistic felling is a fancy way of saying helping trees to fall into the river in a way that simulates them falling naturally. This approach helps to meander the river and change the flow rates.


Felling the trees so they fall into the water in a naturalistic way helps improve the habitat of the river- Credit: Jez Perkins

Areas of water behind submerged fallen branches and brash tend to have a slower flow and can create safe nursery grounds for young fish. A larger trunk angled into the water can narrow the channel which increases the flow rate, scouring the river bed and clearing it of silt. The clean gravel provides the habitat brown trout like for breeding – they use their tails to create hollows in the gravel called redds into which they deposit their eggs.

The slower-flowing areas around the edges allows vegetation, such as sedges, to establish which provides a good habitat for the aquatic invertebrates under the water at the edge of the river. It also creates good habitat along the edge of the bank for larger animals such as the water vole to shelter and feed.

We are really lucky in that the stretch of the river Mimram flowing through Panshanger Park is actually in very good condition. However, there are always way to improve it for wildlife and we look forward to seeing the benefits that this work brings in future years.

There are always plenty of opportunities to get involved at Panshanger Park. If you would be interested in helping with conservation work or events within the park more information can be found at panshangerpark.tarmac.com/volunteering