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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
Birds, people and papyrus swamps: balancing livelihoods
and biodiversity conservation
Ilya Maclean
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
Maclean et al. (2003) Bird Conservation International, 13: 283-97
Five species considered
endemic / near-endemic
Background
Maclean et al. (2003) Bird Conservation International, 13: 283-97
Papyrus Canary Serinus koliensis Carruthers’s Cisticola Cisticola carruthersi White-winged Swamp Warbler Bradypterus carpalis
Papyrus Yellow Warbler Chloropeta gracilirostris (VU)
Papyrus Gonolek Laniarius mufumbiri (NT)
Background
Wide variety of birds associated
with papyrus swamps
Most not solely reliant on
papyrus
Five species considered
endemic / near-endemic
Regionally, among most-
threatened 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
• 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
Albertine Rift
Western Kenya
Lake Mweru
Maclean et al. (2003) Bulletin of the African Bird Club, 10: 94-100
Results: habitat loss
Mean percentage annual rates
of wetland loss (1984-2000)
Rice schemes
Extensive cultivation & dairy farming
Dredging & Brick-making
Maclean et al. (2011) Diversity & Distributions, 17: 480-90.
Results: bird loss
Maclean et al. (2011) Diversity & Distributions, 17: 480-90.
Rarity weighted bird density index Annual rates of wetland loss
Red = high Blue = low
0
20
40
60
White-winged
Warbler
PapyrusYellow
Warbler
Carruthers'sCisticola
PapyrusGonolek
PapyrusCanary
Perc
en
tag
e l
oss (
1985-2
000)
Mean wetland loss 1985-2000
Bird densities higher in
areas of high drainage
Bird declines >> wetland
loss
Results: avian responses to
disturbance
Maclean et al. (2011) Diversity & Distributions, 17: 480-90.
A small proportion of wetlands host a high proportion of the birds:
c. 75% of birds hosted by c. 5% of wetlands
Results: avian responses to
disturbance
0
2
4
6
8
10
0 0.2 0.4 0.6 0.8 1
Proportion of swamp disturbed
De
ns
ity
Papyrus Yellow Warbler
Papyrus Canary
Carruthers's Cisticola
White-winged Warbler
Papyrus Gonolek
Principal component of vegetation structure indicative of disturbance
High disturbance
Bird densities
highest in swamps
with low-intensity
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
Maclean et al. (2003) CSERGE ECM 03-09
Everyone has equal income
One person has all income
Poorest people use wetlands the most
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
