Lewis Pate explains how the careful species management has allowed the gradual build up of eagle communities, and proved collaborations can work.
White-tailed eagles (Haliaeetus albicilla) were re-introduced to Scotland through a series of three main release phases starting on Rum in 1975, followed by Wester Ross in the 80’s and finishing on the east coast in 2012.
A couple of unsuccessful smaller attempts were made prior to these in Argyll and on the Fair Isle, however they were unsuccessful due to insufficient numbers of birds released. There is a current translocation project under way to re-establish birds on the Isle of Wight using donor stock from the established population in Scotland.
A species that is part of a group of 8 Haliaeetus eagle species including the Bald Eagle, Madagascar Fish eagle and the African Fish Eagle, it is the 4th largest eagle species in the world with a wingspan of 2-2.3m and a significant body mass of up to 7kg.
The species is now firmly established to some of its previous range with strong populations on Skye, Mull, the Outer Hebrides, the Small Isles and the west coast mainland. They have now spread to the Orkney islands with the last living albino female shot further to the north on Unst in Shetland in 1918. They are now slowly spreading back to much of their native range and have appeared in the Cairngorms with birds making their way as far east as Aberdeenshire and a growing population of birds in Argyll.
Between 1975 and 2012 a total of 232 Norwegian eagles were released in Scotland and we now have a sustainable breeding population of around 130 pairs starting with the first successful breeding attempt on Mull in 1985.
The birds faced years of control and persistent persecution to satisfy the demand from egg collectors, taxidermists, vermin controllers, milliners and suffered from poisoning and shooting over sporting estates.
The main historical and current threats these birds face are from conflict with human beings, with added pressures from hypothermia, disease, collisions with trains, power lines and wind turbines. They are now afforded the highest level of protection under Schedule 1 of the Wildlife and Countryside Act and it is an offence to intentionally disturb or harm them. This does not ensure their safety unfortunately and there is a considerable way to go for raptor protection in Scotland if we are to progress in a sustainable way.
There is now an established management scheme in place to reduce conflicts between upland sheep farming operations and the range expansion of WTE’s in Scotland.
The current Sea Eagle Management Scheme (SEMS) is run by SNH with specialist advice from contractors to find adaptive solutions to wildlife conflict. The scheme looks to support changes in management practices to try and reduce loss of lambs at key times, offering advice to farms and crofts and employing dedicated field workers to focus on specific areas and monitor farms.
Significant advisory and field work is undertaken each year to engage with land managers and better understand the behaviour, productivity and population dynamics of this substantial avian predator. Coloured leg rings are fitted to nestlings across as many breeding sites as possible each year and the increasing use of trail cameras, satellite tags and field observations helps to build our understanding of how this species occupies our natural environment. Additional work is undertaken to clear nests of prey remains and analyse these to determine dietary preferences of individual pairs.
The established success of the various re-introduction projects has finally paid off and this slow breeding and long-lived raptor is now a common sight across the better-established areas on the west coast and beyond. Landscape-scale species conservation has been achieved which has been an amazing success story for those involved with the re-introductions and ongoing monitoring of these iconic birds.
The birds also have significant tourism value as a species that visitors coming to Scotland are keen to see. There are numerous accommodation and wildlife watching businesses both land and marine-based taking advantage of this opportunity with a growing economic benefit to some rural communities.
This species does however highlight the requirement to balance essential environmental restoration with the current agricultural systems in upland areas. It also focusses attention to how we need to integrate land management practices more effectively to ensure a sustainable way forward in land management and conservation.
Species re-introductions and population re-enforcements need to properly planned and risk-assessed and we know from our past that mistakes have been made with the establishment of invasive non-native species (INNS) in the wrong place. Managing INNS costs millions of pounds every year to manage and causes serious damage to our natural environment, impacting on our indigenous species through competition for resources, hybridisation or predation to a level that is so severe they can be virtually eradicated as a result. Red Squirrel water vole, Scottish wildcats, have all suffered and our native and commercial woodlands and river systems have also been severely impacted from invasive plants that continue to have serious consequences for management.
Appropriately managed projects are now established as productive and valuable tools in the management of wildlife conservation in the UK and beyond. These projects are delivering important landscape-scale conservation benefits and have successfully focussed on golden eagle, Eurasian beaver, pine marten, red kites, and red squirrels to name a few. They have re-established and bolstered populations of mammals, birds, invertebrates and vascular plants across many former ranges with significant value to the restoration of our depleted native biodiversity.
Hopefully with increased investment we can develop more carefully managed projects to support our natural environment and the species that occupy it for future generations to enjoy.