Contrary to what the consultant to the Hawk and Owl Trust said in your article of May 8, there are two principal reasons for burning heather, particularly on the North York Moors.
One is to manage the build-up of plant material which poses a wildfire risk and which, when it catches fire in hot, dry conditions, burns with such intensity that it damages not just the moss layer at ground level but also the very carbon rich peat which is underneath.
On Fylingdales Moor (since managed by Hawk and Owl Trust) a devastating such wildfire took hold in 2003 and completely destroyed the peat over about 350 acres, which had been laid down over thousands of years. Massive quantities of carbon were released into the atmosphere or washed away. A further 350 acres were badly damaged and it all cost about £250,000 to revegetate it.
It took the fire and rescue service three weeks to bring this fire under control and cost them over £140,000 and two of their staff suffered significant injuries.
The other main reason prescribed burning is done is to break up the habitat and create edge effect which is so important for improving biodiversity for invertebrates, reptiles and many of the birds for whom the moors represent an important breeding ground.
Indeed, they carry the highest European designations - Special Area of Conservation (SAC) and Special Protection Area (SPA) - for both quality of the vegetation and for breeding birds because this management has provided the ideal habitat. Seventy five per cent of heather moorland left in the world is found in Britain.
In particular, the merlin which is our smallest bird of prey and one of the two trigger species for the Special Protection Area (SPA) designation, is increasingly reliant on moorland managed like this to sustain its population. The UK population of merlin is about two thirds of that compared to harriers and 80 per cent of breeding records are now associated with moorland managed this way accordingly to a recent study.
Areas regenerating from small management strip burns are the areas chosen by the golden plover and green plover to make their nests and are vital for many other ground nesting birds such as the curlew and grouse to forage for insects and as places to dry out after rain when the longer adjacent vegetation is wet.
It will be interesting to see what observations the Harrier Help Campaign team of spotters come up with. In recent years there have been successful nests on the North York Moors of montague and marsh harrier. There are 1.3 million hen harriers in the world and less than 1 per cent of them nest on heather moorland.