In northern England, the black-grouse population has dropped to its lowest-ever recorded level, and male black grouse numbers have almost halved since last spring.
Black grouse male numbers had previously increased from 773 in 1998 to 1,200 in 2007, but cold, rainy summers in 2007 and 2008 led to poor breeding seasons, with only 730 recorded in 2009.
In the North Pennines, where black grouse have previously thrived, male numbers were at an all-time low of 400 in spring 2010.
Dr Phil Warren, research scientist for the GWT, has been working on the North Pennines Black Grouse Recovery Project for 15 years. He observed that the red-listed black grouse has suffered threats in the form of habitat loss and increasingly intensive agriculture.
Dr Warren added: ‘This is a huge blow to all those that have been involved in black grouse recovery. However, it does underline the importance of conserving populations at levels that can withstand these periodic random factors, such as weather.
‘Our work to improve the conditions on the fringes of moors has proved very important, as the population in the Pennines has recovered sufficiently to withstand these extreme weather conditions.’
The GWT has been encouraging moorland managers to establish small areas of native woodland on the edge of moors. These can provide food when other sources, such as heather, are covered by snow.
Research shows that, in these areas, the number of male black grouse has only declined by 15%; at sites without woodland areas, that number was 50%.
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