Evidence of breeding at this site was found on 27 June 2009 by John Lyden when activity and a food pass were observed. On 15 July we observed a food pass and the female carrying prey to the nest site allowing us to pin-point the location for a future visit (Kevin Collins, Allan Mee). Unlike Slievenamuck this breeding site in the Knockmeldown Mountains is classic heather moorland, a much reduced and sadly rare breeding habitat for harriers on Irish hills these days. The nest site itself was at 450m in heather although the Knockmeldowns rise to 794m at their highest point.
On 29 July Kevin Collins and Allan Mee visited the site and located the nest with three well-grown chicks. Although no adults were present initially both returned to the site later. Chicks were removed to some 5 metres from the nest to minimise trampling of vegetation around the nest during transmitter attachment. Based on biometrics (tarsus, weight) and iris colour the nest contained two male and one female chick. A 12g solar satellite transmitter was attached to the female. Chicks can be aged reasonably accurately by measuring their wing length. Thus we estimated that our female chick (202mm) was 24 days old and suitable for transmitter attachment. The rest of the brood ranged from 24-27 days old. The transmitter harness was prepared prior to the nest visit requiring at least four different sizes of neck collar and sternum loops to be made to fit a range of chick sizes. Thus, in the field the only stitching to be done is one double stitch. After attachment and taking biometrics (weight, wing, tarsus), sexing and attaching a metal BTO ring, we replaced all chicks together in the nest. Soon after leaving both adults returned to the nest site, at least one carrying prey while we were at the nest.
Although initially the data was too poor quality (Class 1, A, B etc) to estimate fledging and early movements around the nest site, the first good quality fix (Class 3) showed that this female had moved 6.2km ESE by 15 August. However, by late on 19 August the female had made a significant movement 153km NE to roost on the west site of the Great Sugar Loaf Mountain, Co. Wicklow! Watch out for the next exciting movements of this female by clicking on Maps and GPS Tracking and selecting female Hen Harrier Gráinne!
Many thanks to Cyril Saich, District Conservation Officer, National Parks & Wildlife Service, for all his help, encouragement, and permission to carry out this study which we hope will reveal much that is as yet unknown about the lives of Irish Hen Harriers.