Provide medicated grit for grouse

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A controlled experiment during 1996-2000 on two moors in northern England (Newborn & Foster 2002) found that red grouse Lagopus lagopus scoticus in an area provided with quartz grit treated with anthelmintic drugs (drugs to treat parasitic worm infections) raised between 38% and 100% more chicks than grouse in a control area (treatment areas: 4.9-7.1 chicks/hen estimated from 36 radio-tagged birds and 4.9-6.7 chicks/hen estimated from 125 birds seen on counts using pointing dogs vs control areas: 1.9-4.8 chick/hen from 36 tagged birds and 2.8-4.5 chicks/hen from 117 on dog counts) and had significantly lower levels of infection of the parasitic nematode Trichostrongylus tenuis (34% fewer worms over five years). This was despite the fact that the medicated areas did not have larger broods or higher hatching success (medicated areas: 9.6 eggs/clutch, 90% hatching success for 161 clutches; control areas: 9.4 eggs/clutch, 94% hatching rate for 153 clutches). Survival rates of adults did not vary between medicated and control areas.

    Study and other actions tested
Please cite as:

Dicks, L.V., Ashpole, J.E., Dänhardt, J., James, K., Jönsson, A., Randall, N., Showler, D.A., Smith, R.K., Turpie, S., Williams, D.R. & Sutherland, W.J. (2020) Farmland Conservation. Pages 283-321 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.


Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Farmland Conservation

This Action forms part of the Action Synopsis:

Farmland Conservation
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