Published in support of the UK Biodiversity Action Plan for black grouse

Forestry

The amount of open habitat, especially moorland, under conifer plantation increased significantly in the second half of the 20th century. In the short-term, this benefited black grouse: while the trees are becoming established, the ground vegetation, often containing heather and bilberry, thrives because it is fenced off from grazing animals. This provides more nesting cover and food for black grouse, and high densities of young hens can be attracted. However, after 10 to 15 years, the tree canopy closes, shading out this vegetation and suitable conditions rapidly diminish. Typically after about 40 years, the trees are felled, allowing the shrub-layer to regenerate again.

Afforestation has probably led to a reduction in the overall habitat suitable for black grouse, especially combined with the use of deer and stock fences to protect the trees, though it can provide a much-needed periodic boost in numbers.

plantation forest
Mature conifer plantations provide little habitat for black grouse unless management is undertaken. RSPB Images 2001_2353_009

In large forests, the clearfell rotation, which produces stands of varying age adjacent to each other, allows the periodic regeneration of heather and bilberry in each compartment. Studies in Argyll (Haysom 2001) found that lekking males are more likely to occupy plantation areas with a dense shrub layer if they are large and contain trees of variable age. The second rotation of forestry can hold as many lekking males as a new planting.

What can be done?

Other factors in the decline
Agriculture
Deer
Fencing
Predation
Shooting
Weather