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Andrew Balmford Department of Zoology, University of Cambridge. Nature and ecosystem services: a global perspective . 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?. Overkill
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Andrew BalmfordDepartment of Zoology, University of Cambridge Nature and ecosystem services: a global perspective
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? Overkill 59% decline in large mammals inside African reserves since 1970 Habitat loss ~50% of land already converted to farming, forestry, towns… 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
What’s happening to nature? Emerging threats climate change eutrophication ocean acidification
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…)
Marginal benefit or cost of conversion ($/km2/y) Proportion converted Why does it matter? Economics of ecosystem services Converting what’s left of nature often benefits private individuals, but at growing cost to society as a whole – nowadays often total costs > benefits 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 dry season fog capture prompted community to declare 40% of their land as a reserve Esmereldas woodstar
Grounds for hope? Dutch National Ecological Network is (almost) on target to give 17.5% of land back to nature by 2018
What lessons can we learn? • despite diversity, recurrent themes: • being bold • being good, not perfect • passionate and imaginative leaders • broadening the case approaches, motives and participants are diversifying - one size doesn’t fit all
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
Grounds for hope? 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? www.americanalbacore.com photo: Richard Herrmann America Albacore Fisheries Association 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)
AAFA 4000km Some success stories MSC certified fishery www.msc.org 98 fisheries and >6000 products now certified worldwide – represents >7% of fish caught for human consumption; almost 200 more fisheries under assessment / pre-assessment problems – Standard criticised as too demanding/easy, limited baseline data, and process costly so limited uptake in developing countries Marine Stewardship Council by becoming MSC-certified AAFA gained access to European markets
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
Historic area converted (%) 20 0 40 60 80 100 Pre 1950 1950-1990 Predicted 2050 The emptying glass… 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 Tropical/subtropical coniferous forest Deserts and zeric shrubland Montane grassland and shrubland Tropical/subtropical moist forest Temperate conifer forest Boreal forest/taiga Tundra Habitat conversion before after Millennium Ecosystem Assessment 2005
The emptying glass… Overharvesting 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
The emptying glass… Underlying drivers population growth rising per capita consumption externalities and discounting growing disconnect from nature world total world rural world urban population 1950-2030, UNPD 2006
1811 1934 1960 1960 1978 1978 1996 The importance of optimism Thomas Hardy Dorset heathland Norman Moore Moore 1960 J appl Ecol 50: 369-391
Some success stories Loma Alta, western Ecuador Dusti Becker recognised importance of forests for intercepting dry-season (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