The black grouse and forest boundary

"As the altitude increases, vegetation must adapt to the harsh climate conditions. The constraints become such that the growth of trees is no longer possible. Only a few conifers and stunted birches survive, before long replaced by shrubs and then an alpine moor. Between forest areas and alpine meadows, this ecological environment, known as the ""forest boundary"", is home to the black grouse or black cock, which provides the food and tranquillity necessary for its survival."