Guest blog by Dr Graeme Buchanan and Dr David Douglas, RSPB Centre for Conservation Science
Two peer-reviewed papers recently published online from the RSPB Centre for Conservation Science contribute to our knowledge about upland birds and their habitat requirements. They inform how we can manage moorland better to halt and reverse the losses of upland bird populations.
Upland birds in decline
Uplands habitats cover a large part of the UK. Moorlands, typified by heather, blanket bogs and unimproved grass are a major habitat within the uplands.
The populations and range of many of the UK’s upland birds are in decline. Some of these species, such as curlew and meadow pipit, are of global conservation concern.
Photo of curlew by Andy Hay (rspb-images.com)
Our uplands are home to important populations of birds. The mix of moorland species is particular to the UK, so we must take action to reverse these declines.
New RSPB research gives us a better understanding of why the abundance of birds vary across the uplands, and how birds respond to management interventions. This science is important as it will allow us to recommend conservation measures.
Study reveals how habitat management and environmental factors influence moorland bird populations
An RSPB study published in the journal Ibis quantifies the importance of physical characteristics (climate, topography), landscape scale management and site-based management (predator control and grazing) and how this affects the abundance of a selection of upland birds including curlew, golden plover and whinchat in four areas of the UK.
Photo of golden plover by Andy Hay (rspb-images.com)
One of the results from the research is that predator control for game management is strongly linked to greater abundance of waders, indicating the species benefit from more predator control. This is not a new finding but we were able to compare the importance of this effect to others than can be altered through management. Vegetation characteristics (structure and composition), which are a product of the level of grazing on moorland sites were of equal importance when it comes to determining the abundance of waders and grouse. Consequently, management to optimise numbers waders as well as grouse should consider both aspects of site management.
The research also shows that vegetation composition and structure strongly influence the abundance of passerine species such as whinchat and wheatear.
The study concludes that the most beneficial management will vary between species, highlighting the importance of a mosaic of managements across uplands to benefit all species.
The 155 evaluated sites comprised unenclosed bog, heath and grassland, known collectively in the UK as moorland, and were managed for birds through a mixture of grazing, game shooting and nature conservation.
We could not have undertaken this study without access to these areas, and we are very grateful to the owners for allowing us to count breeding birds and survey vegetation on these plots.
New research reveals how bird populations change in relation to management
RSPB research published in the journal Bird Study focuses on breeding bird responses to a range of moorland management interventions at Geltsdale reserve in Cumbria.
This site is co-owned by RSPB and the Weir Trust and is a key site for RSPB’s upland conservation and advocacy.
Between 1999 and 2013, grazing pressure was reduced in response to wider concerns that high sheep grazing pressure in the uplands was detrimental for habitats and the birds that rely on them. The study also considered the affects of moorland burning, but following a better understanding of the impacts of this on peat, it was replaced by cutting to manage vegetation.
Golden plover, curlew, wheatear and skylark responded positively to management that is likely to create shorter vegetation. For species such as golden plover and wheatear this is consistent with what we know about their habitat preferences from previous studies.
Photo of wheatear by Ben Hall (rspb-images.com)
Conversely, whinchat responded positively to increasingly dense vegetation at the ground layer, again consistent with previous work.
The results of both studies highlight that different bird species respond to different management interventions and environmental conditions.
Using research to inform moorland management
Therefore, planning at multiple spatial scales may be required to deliver a mix of habitat types and structures that optimises the potential benefits for multiple species when moorland is managed to benefit a range of bird species.
A key mechanism for delivering sympathetic habitat management for birds in the uplands is agri-environment schemes, which encourage farmers to deliver particular management options that will benefit wildlife and the environment. The results of these studies should help to inform the design of options available within these schemes, to maximise the effectiveness of these schemes.
As mentioned in recent blogs, RSPB are currently testing the response of breeding birds to targeted management through our Curlew Trial Management Project.