Overall biodiversity has decreased on Ilkley Moor since Bradford Council granted a licence allowing grouse shooting in 2008. Indigenous natural predators, including corvids and foxes, are shot to preserve red grouse for guns. Species which should be nesting on the moor, including hen harriers, peregrine falcon and merlin, are absent. Intensive management techniques including burning, used to increase game bird numbers, also harm the habitat. These damaged ecosystems also fail to support certain specialist wildlife, for example causing a decrease in populations of dunlin and riverine biodiversity.
What should be a reserve for wildlife is now becoming devoid of any species other than red grouse.
Unnatural Grouse Population
Abnormally high numbers of red grouse are present on Ilkley Moor due to intensive management techniques being used which are designed to deliver more birds to be shot. This is a problem unique to shooting moors. In the absence of predators like foxes and crows, the crowded grouse become susceptible to diseases and parasites. This requires treatment with medicated grit, which acts as an insecticide to invertebrates which leaches into the surrounding soil. Invertebrates are, of course, a key part of the diet for breeding birds.
Toxic Lead Shot
During grouse shoots themselves, toxic lead ammunition is discharged across Ilkley Moor. The impact of this substance is particularly stark with respect to birds of prey, especially if they consume shot game birds. Studies have shown increased levels of lead in the diet can cause sickness, death and reproductive failure in birds of prey.The Oxford Lead Symposium recently found spent shot now appears to be the only significant, geographically widespread and common source of unregulated environmental lead contamination to which wildlife is exposed.