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Birds, people and papyrus swamps: balancing livelihoods and biodiversity conservation Ilya Maclean [email protected] Environment and Sustainability Institute, University of Exeter Background Birds good indicators of ecosystem health: • occur in wide variety of habitats • sensitive to environmental change • Well known and easy to monitor Much conservation policy is based on birds • EU Birds Directive • Ramsar Convention • BirdLife International IBA programme Background Wide variety of birds associated with papyrus swamps Most not solely reliant on papyrus Five species considered endemic / near-endemic Maclean et al. (2003) Bird Conservation International, 13: 283-97 Background Papyrus Yellow Warbler Chloropeta gracilirostris (VU) White-winged Swamp Warbler Bradypterus carpalis Papyrus Gonolek Laniarius mufumbiri (NT) Carruthers’s Cisticola Cisticola carruthersi Papyrus Canary Serinus koliensis Maclean et al. (2003) Bird Conservation International, 13: 283-97 Background Wide variety of birds associated with papyrus swamps Most not solely reliant on papyrus Five species considered endemic / near-endemic Regionally, among mostthreatened and least adequately protected Maclean et al. (2003) Bird Conservation International, 13: 283-97 Key questions • How threatened papyrus birds (and why)? • Can conservation resources be targeted? • Are bird-based policies compatible with people? Methods • Biodiversity surveys across Lake Victoria basin • Analysis of satellite imagery • Socio-economic modelling Results: taxonomy Albertine Rift • Papyrus Yellow Warbler probably three species: • Three highly disjunct populations • Plumage, biometrics, size, bare parts & vocals all differ • Species / population in Kenya Critically Endangered • Confined to very small number of sites • All sites highly threatened Maclean et al. (2003) Bulletin of the African Bird Club, 10: 94-100 Western Kenya Lake Mweru Results: habitat loss Rice schemes Dredging & Brick-making Extensive cultivation & dairy farming Mean percentage annual rates of wetland loss (1984-2000) Maclean et al. (2011) Diversity & Distributions, 17: 480-90. Results: bird loss Annual rates of wetland loss Rarity weighted bird density index Bird densities higher in areas of high drainage Bird declines >> wetland loss Red = high Blue = low Percentage loss (1985-2000) 60 40 20 Mean wetland loss 1985-2000 0 Whitewinged Warbler Papyrus Yellow Warbler Carruthers's Cisticola Papyrus Gonolek Papyrus Canary Maclean et al. (2011) Diversity & Distributions, 17: 480-90. Results: avian responses to disturbance A small proportion of wetlands host a high proportion of the birds: c. 75% of birds hosted by c. 5% of wetlands Maclean et al. (2011) Diversity & Distributions, 17: 480-90. Results: avian responses to disturbance Density 10 Papyrus Yellow Warbler 8 Papyrus Canary 6 Carruthers's Cisticola White-winged Warbler 4 Papyrus Gonolek Bird densities highest in swamps with low-intensity disturbance 2 0 0 0.2 0.4 0.6 0.8 1 High disturbance Proportion of swamp Principal component ofdisturbed vegetation structure indicative of disturbance Maclean et al. (2006) Biological Conservation, 131: 349-58. Conclusions: birds Birds adversely affecting by habitat loss Birds not adversely affected by low-intensity disturbance • Long history of disturbance + extinction filter? • Mimics of disturbance of evolutionary time scales – e.g. large herbivores? Possible to target conservation resources efficiently Results: value to people • Drainage lowers value • Value maximised with low-intensity use • If people are poorer, optimum value changes Maclean et al. (2003) CSERGE ECM 03-10 Results: value to people Poorest people use wetlands the most Everyone has equal income One person has all income Maclean et al. (2003) CSERGE ECM 03-09 Conclusions: people Papyrus used unsustainably Poverty & income inequity increase Two equilibria: (1) Sustainable resource use, moderate poverty & income inequity (2) Unsustainable resource use, high poverty & income inequity As human population increases, switch from state (1) to (2) increasingly likely Maclean et al. (2011) Environmental Management, 47: 218-29. Conclusions: general Win-win for birds and people depends on poverty reduction The way forward 1. Recognise that low-intensity resource use is compatible with conservation 2. Poverty-reduction should be pivotal to conservation policy 3. Seek to diversify income sources as this will break circle of poverty Acknowledgements Fieldwork assistance: Jez Bird, Mark Hassall, Steven Katungi, Simon Mahood, Rob Martin, Rowan Martin, Richard Moores, Nicodemus Nalianya, Oliver Nasirwa, Johnson Ruhakana, Johnson Tumahairwe Logistic support / advice: Leon Bennun, Achillis Byaruhanga, Nigel Collar, Lincoln Fishpool, Janet Havers, Alfred Owino, Derek Pomeroy, Charlie Williams Academic Collaboration: Ros Boar, Mark Hassall, Iain Lake, Charles Lugo, Nicodemus Nalianya, Oliver Nasirwa, Rob Tinch, Rob Wilson Funders: University of East Anglia, British Ecological Society, Royal Geographic Society, African Bird Club, British Airways