Fieldwork protocol for monitoring Hen Harriers

Fieldwork protocol for monitoring Hen Harriers

Protocol compiled by the Wildlife Management and Licensing Service. 

Last updated: 2015


Schedule 1 licence holders have cooperated over many years to minimise disturbance to nesting birds. Unfortunately, there are very few breeding hen harriers in England, and the number of Schedule 1 licence holders is comparatively large. 

Careful coordination and adhering to the following protocol will prevent unnecessary visits/disturbance:

  1. Observations of nest building, or other signs of nesting behaviour, should be reported to the coordinator at the first opportunity. No attempt should be made to visit a nest without prior communication with the coordinator.
  2. Nest sites should be kept under observation from a suitable vantage point that does not cause disturbance to the birds, to confirm continued nesting activity.
  3. A nest visit should be made to determine clutch size approximately 10 days after incubation commences. All nest visits are to be undertaken in dry weather.
  4. After a gap of approximately 10 days following the first indications of hatching, a further nest visit should be made to record brood size.
  5. When the oldest chick is estimated to be approximately 28–30 days old, a visit could be made to ring and wing-tag chicks. Radio transmitters, if they are to be fitted, would be attached on a final visit.
  6. The nest should be kept under observation to determine the number of young successfully fledged.