Supporting Better Public Awareness

1.6km of the River Tirry and 500m of the Allt Chaisegail tributary have been restored by planting native trees. The Tirry catchment is largely devoid of native riverbank woodland which provides shade, nutrients, and improved habitat. Once established, the project will make a significant contribution to the overall native riparian woodland cover on the River Tirry.

The River Tirry is home to a recovering Atlantic salmon population, producing an estimated 5,000 smolt emigrants annually. Much of the upper catchment is identified via the Scotland River Temperature Monitoring Network as being extremely vulnerable to rising water temperatures.

Kyle of Sutherland Fisheries Trust worked together with three different landowners (Shinness Estate, Lairg Estate and a further private landholding) to plan and execute a complex ‘ultra-riparian’ planting project. Voles, brown hares, sika and roe deer were present in numbers so a range of different tree protection measures were deployed. Alder and willow species were planted closest to the waterline, protected by small biodegradable guards. Birch, hazel and aspen were planted slightly further back from the river, protected by 1.5m tree guards. Within a deer fenced part of the site, only voles and brown hares posed a risk so less protection was required. Alder, being the least palatable species was planted freely along the riverbank.

Within a deer fenced section, alder planted freely and small tubes protecting willow, hazel, birch and aspen.

Tirryside provides home to numerous species of birds including critically endangered waders so Kyle of Sutherland Fisheries Trust worked closely together with RSPB to plant using a low density ‘clumped’ design, providing naturalistic flight pathways for wading birds, also serving as open canopy spaces for water voles. Areas near to existing remnants of broadleaves and Scots pine were left unplanted to allow natural regeneration with the sensitive planting carried out by contractors, Alexander Forestry.

Ongoing monitoring is planned, including tree establishment and browsing pressure, aquatic invertebrates, breeding birds, fish populations and fixed point photography.

The project is funded by Kyle of Sutherland Fisheries Trust and Mossy Earth, with a generous contribution of tree guards having been made by The Woodland Trust.

Plans are well underway for catchment-scale restoration with Shinness Estate. During 2022 Shinness Estate, working together with neighboring estates, commissioned a herbivore population census using a thermal drone. This census indicated high densities of non-native sika deer in the lower catchment and high densities of red deer in areas of the upper catchment, preventing natural regeneration of woodlands. A 5-year deer management plan has been established.

Map above showing restored areas in green.

River Tirry looking north to Tirryside Broch

Biodegradable browser protection deployed within the flood zone