Guest post by Stephen Ewing from the RSPB's Centre for Conservation Science
High mountain habitats in the UK, which reach their greatest extent in places like the Cairngorms, are beautiful, but remarkably unforgiving and harsh environments. The severe conditions mean that only the hardiest cold-adapted specialists can eke out an existence. The report released recently by the Intergovernmental Panel on Climate Change, however, highlights that animals and plants associated with these mountain-top ecosystems may be at particular risk from climate change because, unlike species at lower altitudes, they do not have the option of moving to higher elevations to adapt to a warming climate.
In the UK these species include ptarmigan, snow bunting and dotterel. The latter species, in particular, has long fascinated ornithologists in the UK. The dotterel is a small confiding plover species that winters in the semi-deserts and steppes of North Africa, before migrating to the UK and other parts of Northern Europe and Asia for the breeding season. Dotterels arrive here towards the end of April in small parties of migrating birds, congregrating and settling in areas dominated by moss and heaths. Dotterels flout traditional avian sex roles; it is the females, the larger and more colourful of the sexes, that court the males, perhaps one of the characteristics that make the dotterel such an enigma.
Female Dotterel in favoured Racomitrium moss heath
So, does the spectre of climate change cast a shadow over dotterels in the UK? A joint RSPB and Scottish Natural Heritage (SNH) survey carried out in 2011 found that the UK population has decreased by a whopping 57% since the late 1980s (from 980 to 423 breeding males), and ongoing analyses suggest that this decline has coincided with a retreat to higher altitude sites.
Both of these results are in line with the projections of climate change models that predict the disappearance of the dotterel from much of its UK breeding range by the end of the 21st century. But, while this evidence is clearly suggestive, it does not allow us to unambiguously ascribe these changes to climate change. High mountain habitats, like other ecological systems, are complex, and various other pressures, including overgrazing and nitrogen deposition, may be at play, and cannot yet be discounted. Nonetheless, RSPB (in conjunction with partners at SNH and Aberdeen University) is taking a lead role with new research that aims to disentangle the relative impacts of climate change and other pressures on the UK dotterel population.
So, RSPB is working hard (with partners) to both understand and minimise the potential impacts of climate change on this species. Through our reserve network, we provide resilient refuges (e.g. Abernethy) for these birds to persist and breed. Through our monitoring work, we document changes in the health of the population and the impacts of different stresses. And through our research, we strive to better understand the mechanisms through which climate change may affect dotterel, so that we can develop conservation solutions that help them persist in the UK long into the future in spite of any challenges posed by climate change.