Due to the decline of hen harrier numbers in Ireland over previous decades, linked primarily to habitat loss, it is imperative that we fully understand and establish the locations, demographics, dynamics and threats relating to this species during both the breeding and winter seasons. This task has been addressed by The Irish Hen Harrier Winter Survey (IHHWS) in Ireland over the last 15 years. The citizen-science scheme involves a team of skilled surveyors, monitoring the species and gathering invaluable ecological information on our wintering hen harrier populations. Our Ornithology team are included in this team of highly dedicated surveyors, taking part in a voluntary capacity. Collating this data provides a better understanding of the current status of Irish hen harrier populations and helps devise efficient mitigation plans for the continued conservation of the species.
During winter months hen harrier will gather at night, in what are known as roosts. These roosts offer a safe haven for the birds where they can shelter and stay warm during the long winter nights. These roosts can be communal or solitary and the number of individuals occupying a roost can vary greatly in response to many factors such as disturbance or availability of prey. In some cases, winter roosts will also act as breeding sites for hen harrier and so, some sites will host hen harrier individuals all year round. Therefore, it is crucial that these roost locations are carefully identified and monitored for the future protection of the sites and hen harrier present.
The IHHWS have provided a short guide for those wishing to volunteer for this national survey scheme. The guide provides useful information on potential survey locations i.e. suitable habitats for roosting hen harrier, along with the correct survey methodologies for hen harrier roosts watches.