Causes of declineWeather The weather can have a substantial effect on breeding success, with young chicks particularly susceptible to cold, wet weather during mid June to mid July (the first few weeks after they hatch). Rainfall in June, along with predation by crows and the interaction of the two, reduced breeding success during a study at Abernethy Forest, Strathspey. Studies in Belgium found similar trends, including negative effects of wetter June weather and milder winters (Loneux et al. 1997). Capercaillie, a similar large grouse species in serious decline, have had poor breeding success over the last 25 years, linked to the delayed warming of temperatures in April. (Moss et al. 2000). Climate Change Changes in weather patterns may be linked to changes in global climate. Some changes to wildlife have already been noted, such as the northern extension in range of some butterflies. Recent climate change scenarios (UK Climate Change Impacts Programme) suggest that in the uplands, both summer and winter temperatures will increase, as will winter rainfall, but snow will be less frequent, and there will be less rainfall in the summer. Some of these changes (such as warmer, drier summers) may benefit black grouse productivity, but these may be outweighed by bigger changes to black grouse habitats and the timing/extent of insect emergence (chicks' food supply). Modelling suggests that the UK 'climate envelope' for black grouse (its potential range) will reduce to about one-fifth of its current range by 2080. 
Cotton grass is an important host plant for
insects on which black grouse chicks depend. Climate change may reduce
the abundance of plants such as these. Andy Hay, RSPB
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What can be done? Other factors in the decline |