Transcript 10.15 Andrew Balmford

Nature and
ecosystem services:
a global perspective
Andrew Balmford
Department of Zoology, University of Cambridge
What’s happening to nature?
Why does it matter?
Grounds for hope?
What lessons can we learn?
What are nature’s prospects?
What’s happening to nature?
Habitat loss
~50% of land already converted
to farming, forestry, towns…
Overkill
59% decline in large mammals
inside African reserves since 1970
Introduced species
chytrid fungus has already
caused dozens of frog extinctions
→ 1 in 5 spp. already
threatened with extinction
What’s happening to nature?
Habitat loss
No slowing
Population decline
No slowing
→ since 2000:
8/10 indicators of state of nature declined
5/5 indicators of pressure on nature increased
Emerging threats
climate change
eutrophication
ocean acidification
What’s happening to nature?
Why does it matter?
moral, religious and aesthetic
arguments
wild-harvested goods (fish,
timber, medicines…)
less visible services (climate
regulation, storm protection,
crop pollination, disease
control…)
Economics of ecosystem services
Converting what’s left of
nature often benefits
private individuals, but
at growing cost to
society as a whole –
Why does it matter?
Marginal
benefit or
cost of
conversion
($/km2/y)
nowadays often total
costs > benefits
Proportion
converted
Estimated net costs of each year’s loss of nature:
~$3 trillion (Balmford et al. 2002)
$2-4.5 trillion (TEEB 2010)
$6.6 trillion (Trucost 2010)
Why does it matter?
Economics of ecosystem services
1992 Grand Banks cod collapse
cost 40 000 jobs and $3B to
Canadian taxpayer
Loss of waste disposal service
provided by South Asia’s
vultures after tens of millions
poisoned by diclofenac
Loss of storm protection
provided by US wetlands
following drainage
Grounds for hope?
Better understanding
successes could….
identify contributing factors
and so increase future success
rate
restore optimism
Grounds for hope?
Kaziranga NP, Assam
“fortress-and-fines”
conservation coupled
with exceptional
tolerance of wildlife
have increased Indian
rhino numbers from
~20→>2000 in 100y
Grounds for hope?
Loma Alta, western
Ecuador
Measuring value of
high-altitude forest not
for biodiversity but for
Esmereldas woodstar
dry season fog capture
prompted community
to declare 40% of their
land as a reserve
Grounds for hope?
Dutch National
Ecological Network
is (almost) on target to
give 17.5% of land back
to nature by 2018
Grounds for hope?
What lessons can we learn?
approaches, motives and
participants are diversifying - one
size doesn’t fit all
despite diversity, recurrent themes:
• being bold
• being good, not perfect
• passionate and imaginative leaders
• broadening the case
What are nature’s prospects?
conservation interventions do succeed
threats are growing and multiplying
~1 generation left for major changes
but
• same changes required to tackle
climate change and poverty
• ~ half of nature left
• we have the wit and the will to buy
quite a lot of time
Grounds for hope?
Working for Water,
South Africa
~$100M/y project
employing >25 000
previously unskilled
people to clear alien
plants
Huntly bauxite mine,
Western Australia
global range of jarrah forest ±
covered by world’s largest
bauxite concession); mining
involves clear-felling with
minimal restoration
requirements
concerned about future public
opinion, Alcoa invested
massively in restoration R+D – so
restored plots now as rich as
before
Grounds for hope?
a small fishery catching Pacific
albacore with rods (poles) and short
lines (trolls)
biologically sustainable and with
zero bycatch
overharvesting elsewhere drove
prices (in real terms) down from
$3100 / tonne (1981) to $1275 /
tonne (2006)
photo: Richard Herrmann
America Albacore Fisheries
Association www.americanalbacore.com
Grounds for hope?
Marine Stewardship Council
Some success stories
www.msc.org
by becoming MSC-certified AAFA
gained access to European markets
98 fisheries and >6000 products
now certified worldwide –
represents >7% of fish caught
for human consumption; almost
200 more fisheries under
MSC
certified fishery
assessment / pre-assessment
problems – Standard criticised
as too demanding/easy, limited
baseline data, and process
costly so limited uptake in
developing countries
AAFA
4000km
Why does it matter?
Economics of ecosystem services
Loss of waste disposal
service provided by South
Asia’s vultures after >10M
poisoned by diclofenac
Loss of storm protection
provided by US wetlands
following drainage
The glass half-full?
such changes will take time
but same changes are required to
tackle climate change and
developing world poverty
~half of nature still remains
success stories suggest that in some
places we have the wit and the will
to buy quite a lot of time
Habitat conversion
The emptying glass…
Historic area converted (%)
0
20
40
60
80
100
Mediterranean forest and woodland
Temperate grassland and shrubland
Temperate broadleaf and mixed forest
Tropical/subtropical dry forest
Flooded grassland and savanna
Tropical/subtropical grassland and shrubland
before
Tropical/subtropical coniferous forest
Deserts and zeric shrubland
Montane grassland and shrubland
Tropical/subtropical moist forest
after
Temperate conifer forest
Boreal forest/taiga
Tundra
Pre 1950
1950-1990
Predicted 2050
Millennium Ecosystem Assessment 2005
Overharvesting
The emptying glass…
reduced great whale populations
by > two-thirds
eaten >99% of Caribbean’s green
turtles
killed every passenger pigeon
The emptying glass…
since industrial revolution reduced
wild habitats and populations by ~50%
removing rest at ~0.5-1.5% /y
79% of fish stocks now fully exploited,
overexploited or depleted
59% decline in large mammals inside
African protected areas since 1970
extinction rates ~1000 x background
1 in 5 spp. threatened already
Underlying drivers
The emptying glass…
population growth
rising per capita consumption
externalities and discounting
growing disconnect from nature
world total
world rural
world urban
population 1950-2030, UNPD 2006
The importance of optimism
Dorset heathland
1811
Thomas Hardy
1934
40000
35000
1960
Heath (ha)
30000
Norman Moore
25000
20000
15000
1978
1978
10000
5000
Moore 1960 J appl
Ecol 50: 369-391
0
1750 1811 1893 1934 1960 1978 1987 1996 2003
1996
Loma Alta, western Ecuador
Some success stories
Dusti Becker recognised importance
of forests for intercepting dryseason (garúa) fog
dry-season moisture capture in
forest 3-6 times higher than in
plantations or pasture
under conservative assumptions
clearance already cost village 38M
l/dry season (worth $130 000/y)
Becker 1999 Ambio 28: 156-161
What’s happening to nature?
Habitat loss
No slowing
Population decline
No slowing
→ since 2000:
8/10 indicators of state of nature declined
5/5 indicators of pressure on nature increased