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Pearce-Higgins, J.W. 2015. BOU Proceedings – Birds in the entangled bank: advances in foodwebs theory and practice
http://www.bou.org.uk/bouproc-net/foodwebs/pearce-higgins.pdf
Proceedings of the BOU’s 2014 Autumn Meeting
Birds in the entangled bank: advances in foodwebs theory and practice
View other papers from these proceedings at www.BOUPROC.net.
Understanding species interactions helps to identify impacts and conservation
responses to climate change
JAMES W. PEARCE-­HIGGINS BTO, The Nunnery, Thetford, Norfolk IP24 2PU, UK james.pearce-­‐[email protected] There is increasing recognition of the importance of species interactions as a mechanism for environmental change causing population changes in species of interest. This is particularly the case with regard to climate change, where recent studies have emphasized that changes are not generally driven by direct physiological, behavioural or demographic responses to changes in the climate, but instead more often occur in response to changes in the abundance, availability or behaviour of other species within an ecological network, be they prey or predators. Using studies of the impacts of climate change upon birds as an example, recent advances in understanding of the importance of species interactions as a driver of population responses to climatic changes are reviewed and presented. Specifically, the results of a literature review and meta-­‐analysis of the ecological mechanisms underpinning bird population responses to temperature and precipitation changes are outlined, emphasizing that the strongest evidence is in support of impacts mediated through changes in prey abundance, predation or phenological mismatch between predators and prey. Further analysis is presented to identify how the importance of different mechanisms varies between studies, for example in relation to trophic level, taxon and habitat type. In particular, there is good evidence linking negative impacts of summer drought conditions to populations of open-­‐country bird species that feed on soil invertebrates vulnerable to such drought, and strong links between the breeding success of insectivorous passerines and the availability of their invertebrate prey. Although the majority of evidence comes from well-­‐studied temperate systems, the same principles may apply in less-­‐well-­‐studied tropical environments, and some putative examples of this are also shown. Just as understanding species interactions can be important for identifying causes of population change, it may also facilitate the development of management solutions to reverse detrimental change. This is again illustrated with respect to birds and climate change, presenting a number of examples which show how management may be used to alter or restore species interactions, and thus reduce the negative impact of climate change upon the species of interest. The potential opportunities and limits to this approach are discussed.