Climate Change Vulnerability & Adaptation

Coordinators

Dr Rob Simmons & Dr Phoebe Barnard (Birds & Environmental Change, Climate Change & BioAdaptation Division, SANBI)

Research team

Dr Res Altwegg (Applied Biodiversity Research and Climate Change & BioAdaptation Divisions, SANBI), Prof. Dr Katrin Böhning-Gaese, Dr Matthias Schleuning and Baptiste Schmid (Biodiversity and Climate Research Centre, Frankfurt), Dr Lynda Chambers (Bureau for Meteorology, Australia), Dr Yvonne Collingham (Durham University), Dr Richard Dean (PFIAO), Mike Ford (Hermanus Bird Club), Dr Rhys Green (Cambridge University), Professor Phil Hockey (PFIAO), Dr Dave Hole (Centre for Applied Biodiversity Science, Conservation International), Professor Brian Huntley (Durham University), Robyn Kadis (BirdLife Berg River), Dr Alan Lee (Blue Hill Escapes), Margaret McCall (Cape and Tygerberg Bird Clubs), Dr Guy Midgley (Climate Change & BioAdaptation Division, SANBI), Prof Jeremy Midgley, Michelle Malan and William Wyness (UCT Botany), Dr Anton Pauw, Anina Heystek and Lara Croxford (Stellenbosch University), Dr Frank Schurr (Potsdam University), Dr Clelia Sirami (postdoctoral fellow, UCT), Dr Wilfried Thuiller (Université Joseph Fourier), Ross Turner (University of KwaZulu-Natal), Professor Les Underhill (Animal Demography Unit, UCT), Zingfa Wala (PFIAO), Dr Steve Willis (Durham
University).

Overview

Climate change impacts on southern African biodiversity are expected to be serious. Climate change does not operate in isolation, but in concert with other global change drivers, such as land use change, biotic invasion and desertification. These have already significantly altered southern African ecosystems, and the ways in which they compound the impacts of climate change are complex and often difficult to predict in detail. The magnitude and pace of these problems requires a concerted research response, which will generate concrete advice and tools for biodiversity conservation planners, policymakers and habitat managers.

Phoebe Barnard’s team looks at behaviour, phenology, stress ecology, demography and genetic
aspects of vulnerability to climate change and land use change in fynbos endemic birds. The research team is a joint initiative, co-led by the South African National Biodiversity Institute’s (SANBI’s) Birds and Environmental Change Partnership, based in the Climate Change and BioAdaptation Division at Kirstenbosch. The scientific work is done jointly by SANBI and PFIAO with local and international partners, and the policy and planning translation is undertaken mainly by SANBI with partners’ inputs. The work takes place at field sites in the Cape Peninsula, Kogelberg coastal strip, and at several sites along the central and eastern Cape fold mountains.
Key themes and questions. Our approach relies on several fundamental questions, both basic and applied.

Which species are most vulnerable, and why?

Which ecological, behavioural and life history traits influence birds’ vulnerability to range changes and population declines? Analyses of emerging data on occurrence and relative abundance from the Southern African Bird Atlas Project 2 suggest that existing global estimates of extinction risk could underestimate conservation threats to southern African birds (Huntley et al., 2010 Ecography 33:621-612; Huntley et al., in prep. 2011). A paper by Hockey et al. (Diversity & Distributions in press, 2011) suggests that aerially foraging insectivores are among those groups highly vulnerable to climate change.

How do differences in vulnerability affect populations?

By the time we can detect range shifts, local populations have gone extinct, or migratory behaviour has changed. On its own, this is a very unsatisfactory way of understanding vulnerability. To have any chance of successful conservation interventions, we need to track how populations are affected in more detail, and what changes may precede local extinction or colonization. Which kinds of individuals suffer most mortality or stress in populations, under what conditions, and why? How do climate and land use change affect the timing, rate or success of life cycle events such as breeding, migration, or moult? Do normal activities carry increased costs (e.g. energetics) and risks (e.g. predation) for individuals as the climate changes? And do these changes lead to population increases or declines in anticipation of range change?
Long-term population and atlas datasets are analysed with demographic and spatial models, and we have also established a long-term study of colour-marked endemic and non-endemic birds of the fynbos, a globally-important biodiversity hotspot biome projected to suffer significant climate change impacts. The SANBI-UCT team and collaborators have also developed advanced modeling techniques which integrate bioclimatic envelope and demographic tools for much more sensitive analysis (Huntley et al. 2010, op cit.).

What are the risks for threatened, small and peripheral populations?

In a series of current analyses, we are looking at threatened and restricted-range species of southern African biomes, including montane endemics, plant mutualists such as pollinators, and Red Data species. We are in the process of analysing impacts on these birds and the species on which they depend, and which depend on them. Cape Sugarbirds Promerops cafer and proteas are an example of this, as are Orange-breasted Sunbirds and Erica spp. previously believed to be insect-pollinated. New, focused fieldwork is needed to address this effectively, and keen students and funding are sought. Recent surveys of two threatened mountain-dwelling vultures (Bearded Gypaetus barbatus and Cape Vulture Gyps coprotheres) suggest that factors other than poisons and habitat change may help drive population declines. MSc student Jamshed Choudhary and Rob Simmons tested the idea that climate change would negatively influence lower-latitude colonies before higher ones, lower-altitude sites before higher ones, and north-facing cliffs before south-facing ones. All these predictions were supported for both species. In Lesotho, low-altitude sites are being abandoned and birds appear to be retreating to
high-altitude sites. Colonies in Namibia and Zimbabwe have gone extinct as breeding units in the last two decades, a time when temperatures have climbed most rapidly. Behavioural observations of birds on north-facing cliffs also indicate widespread shading of chicks. Studies across a rainfall gradient in Namibia by Rob Simmons, funded by BIOTA, are disentangling the
intricate relationship between bush encroachment, climate change and passerine bird communities in that hot and arid country.

How can conservation planning, policy and management respond to these challenges?

Finally, in SANBI-led work, environmental change research results are increasingly fed into the science-policy interface through targeted publications (Climate Change Booklet), through uptake of data in State of the Environment (SoE) reports, national biodiversity indicators, and contributions to species and habitat management planning. Long-term datasets and large-scale projects such as the Southern African Bird Atlas Project 2 (SABAP2 and its successors) which can inform public policy are being secured financially by SANBI. The goal is to track southern Africa’s bird species over time and space, and provide baselines and ‘snapshots’ of environmental change. Such work is badly needed to shape and strengthen appropriate conservation strategies for the future.