Monitoring and conserving Scotland's birds of prey
The Lewis & Harris Raptor Study Group was formed in autumn 2008, and 2009 was the groupís first field season. The group currently has nine members and we are already building on our knowledge of raptor distribution and breeding ecology on these important islands.
Lewis & Harris is the largest island in Britain covering 2200km² and is surrounded by an array of smaller islands. The landscape is characterised by low rocky hills interspersed with areas of blanket peat and numerous lochs. Most of the ground lies below 200m whilst the hills of North Harris, and parts of Lewis, rise to an altitude of 600-800m. Blanket bog and wet heath are the most common vegetation types over large expanses of the island, although on parts of the west coast areas of fertile calcareous grassland (known as Machair) have developed. The island is predominantly treeless apart from a few exotic coniferous plantations. However, in some areas where grazing animals cannot reach such as crags and islands in lochs, there are fragmented remnants of native woodland. Large parts of the islands are remote and relatively free from human development and disturbance. Extensive sheep grazing and deer stalking are the main land uses.
Our island hosts an unusual but important raptor assemblage during the breeding season. Although only seven species of raptor and one species of owl breed here, we have nationally important populations of golden eagle, white-tailed eagle and merlin. Golden eagles are found throughout the island but breed at particularly high densities in the hills of southern and western Lewis, and in the North Harris hills, which have been designated as an SPA for the species. The population currently stands at around 60 pairs and is still expanding. Almost all the known historical sites are now occupied and in the last few years young pairs have established territories in areas where breeding has not previously been documented. White-tailed eagles established on Harris in 1983 soon after the release on Rum, but the first chick did not fledge here until 2003. Since then breeding success has improved and new pairs have established in most years. The population in spring 2013 stands at 13 territorial pairs, 20% of the Scottish breeding population. Merlins flourish in the huge expanses of open habitat and with an absence of ground predators. Around 100 breeding merlin sites are known.
Voles are absent from the island and as a result the vole specialists are uncommon. Kestrels do breed here but at very low densities and there is only a single confirmed breeding record for short-eared owl. There is no evidence that hen harriers have bred here, despite large areas of apparently suitable habitat. Most woodland species are also uncommon or absent although sparrowhawks have now colonised many of the small coniferous plantations. Buzzards are locally common but are largely restricted to areas around townships and to the coasts, whilst peregrines nest in a few scattered sea cliff sites.
Chair: Robin Reid