Biodiversity, biocapacity and better choices

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No. specieson indexPercent Change1970-200895% Confidence LimitsLowerUpperTotal Global 2688 -28% -38% -18%Temperate 1518 31% 19% 44%Tropical 1354 -61% -70% -49%Terrestrial Global 1432 -25% -34% -13%Temperate 757 5% -3% 15%Tropical 725 -44% -55% -30%Freshwater Global 737 -37% -49% -21%Temperate 436 36% 11% 67%Tropical 386 -70% -80% -57%Marine Global 675 -22% -44% 6%Temperate 438 53% 27% 85%Tropical 287 -62% -78% -32%Biogeographic realms Afrotropical 250 -38% -57% -12%Indo-Pacific 384 -64% -73% -51%Neotropical 515 -50% -69% -21%Nearctic 684 -6% -16% 6%Palearctic 535 6% -7% 17%By country income High income 1732 7% -1% 17%Middle income 1205 -31% -42% -19%Low income 204 -60% -72% -40%Table 1: Trends in theLiving Planet indicesbetween 1970 and 2008,with 95% confidencelimitsIncome categories arebased on the World Bankincome classifications(2008). Positive numbermeans increase, negativemeans decline.Why is the total number of species in the marine,freshwater and terrestrial LPIs more than that ofthe global index?The system the population is assigned depends on where thepopulation is located, rather than where the species lives in general.This means that some species, like Pacific salmon, can have bothmarine populations and freshwater populations, depending onwhere they are in their migration cycle. This effectively “doublecounts” the species numbers (but not the population numbers) asthey appear in both the marine and freshwater LPI cut, but onlyappear once in the global species counts.Cases like this are minimized by asking a series of questionsbefore assigning the population a system:1. In which system does the species spend the majority of its time?2. Which system does the species primarily rely on tosustain itself?3. In which system does the species breed?4. In which system is the species most threatened?Borderline cases are the hardest to assign. For example, how doyou assign a system to a seabird that spends most of its time atsea (where it is at risk from longline fishing), but breeds on land(where it is being impacted by rats preying on its eggs)? These aredealt with on a case-by-case basis and result in some species beingincluded in more than one system, giving rise to the differences intotals seen in Table 1.Are extinct species included in the LPI?Possibly, although thankfully very few. For example, the baiji – orYangtze River dolphin – is now considered to be extinct (accordingto a survey in 2006 that failed to find any individuals in the YangtzeRiver in China). Accidental mortality caused by the fishing gearwidely used in the Yangtze ecosystem is thought to be the maincause. In any case, absence of evidence is not evidence of absence,and biologists normally consider an absence of 50 years as evidencefor extinction.What role has climate change played in the overalldecline of species, particularly in recent trends?It is likely that climate change has caused a decline in populationsof some species, particularly those in vulnerable ecosystems suchas coral reefs, mountains and the Arctic, but the LPI measures onlyaverage trends in species’ populations. We have not analysed thecauses of trends in species’ populations. Over the last 30 years,the principal cause of population decline in wild species has beenhabitat loss or alteration. Over the next 30 years, however, it isWWF Living Planet Report 2012 page 130 Annex: Technical notes and data tables page 131
likely that climate change will be a more important factor affectingpopulation trends, as well as itself being a driver of habitat lossand alteration.Calculating the LPIWhere do the data used in the LPI come from?All data used in constructing the index are time series of eitherpopulation size, density, abundance or a proxy of abundance. Thespecies’ population data used to calculate the index are gathered froma variety of sources. We collate time-series information for vertebratespecies from published scientific literature, online databases (e.g.,NERC Centre for Population Biology [Global Population DynamicsDatabase], Pan-European Common Bird Monitoring Scheme) andgrey literature. Data are only included if a measure of population sizeis available for at least two years, and information available on howthe data were collected, what the units of measurement were and thegeographic location of the population. The data must be collected usingthe same method on the same population throughout the time seriesand the data source referenced and traceable.The period covered by the index is from 1970 to 2008.The year 2008 is chosen as the “cut-off” year for the index becausethere is not yet enough data to calculate a robust index for 2009-2011. Datasets are currently being added to the database to allowthe calculation of the index for those years.How is the Living Planet Index calculated?The LPI is based on population trends in over 2,600 vertebratespecies worldwide. Data on species’ populations from two or moreyears since 1970 are collected from a wide variety of publishedsources and entered into the LPI database. In some cases, wehave data on more than one population of a single species. Foreach population, the rate of change from one year to the nextis calculated. If we have data from only a few, non-consecutiveyears, we assume there was a constant annual rate of change in thepopulation between each data year. Where we have data from manyyears (consecutive or not) we fit a curve through the data pointsusing a statistical method called generalized additive modelling.Where we have more than one population trend for a single species,the average rate of change across all of the populations is calculatedfor each year. Then we calculate the average rate of change acrossall species from year to year. The index is set equal to 1 in 1970, andthe average annual rate of population change is used to calculatethe index value in each successive year.Technical details of the calculationsAnnual data points were interpolated for time series with six ormore data points using generalized additive modelling, or byassuming a constant annual rate of change for time series with lessthan six data points. First, the average rate of change in each year iscalculated across all populations of a species, then across all species.The average annual rates of change in successive years were chainedtogether to make an index, with the index value in 1970 set to 1.Details of each of the methodologies used for each of the cutsof the LPI are outlined below:a. System LPIsEach species is classified as being terrestrial, freshwater ormarine, according to the system on which it is most dependentfor survival and reproduction. The indices for terrestrial,freshwater and marine systems were aggregated by giving equalweight to temperate and tropical species within each system,i.e., a tropical index and a temperate index were first calculatedfor each system and the two were then aggregated to create thesystem index.b. Realm LPIsEach species’ population in the LPI database was assigned toa realm according to its geographic location. Realm indiceswere calculated by giving equal weight to each species, withthe exception of the Palearctic realm, in which families wereaggregated with equal weight. This was done because thevolume of time series data for birds available from this realmfar outweighs all other species put together. The data fromIndo-Malaya, Australasia and Oceania were insufficient tocalculate indices for these realms, so they were combinedinto a super-realm, Indo-Pacific.How has the Living Planet Index changed sinceLPR 2010?On the whole, the results are very similar to the LPIs in LPR 2010.As we continue to add data, we are consistently seeing the samepatterns of population trend at the global level. The followingsection details changes to the data set since LPR 2010.Increases in the LPI DatabaseThe size of the dataset has increased by 13 per cent since LPR 2010(see Figure 59). As populations in the LPI are continually added,so the average trend for each index changes. As a result, the 2012dataset may show differences in the detail of some of the indicesproduced in 2010, but the overall trajectory of the trend remainsroughly the same.WWF Living Planet Report 2012 page 132 Annex: Technical notes and data tables page 133
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Living Planet Report 2012BIOCAPACIT
Page 11 and 12:
the LIVING PLANET INDEXThe Living P
Page 13 and 14:
Exploring the Living Planet IndexTh
Page 15 and 16: The Marine Living Planet IndexThe m
Page 17 and 18: Case study: River dolphinsExample p
Page 19 and 20: Biogeographic realmsBiodiversity tr
Page 21 and 22: the EcologicalFootprintThe Ecologic
Page 23 and 24: What does “ecological overshoot
Page 25 and 26: 2008Gha per capita< 11 - 22 - 33 -
Page 27 and 28: population,URBANIZATION andDEVELOPM
Page 29 and 30: People with different incomeshave d
Page 31 and 32: Ecological Footprint and sustainabl
Page 33 and 34: the Water FootprintThe average glob
Page 35 and 36: Chapter 2: Why weshould care~A sate
Page 37 and 38: Margaret’s storyFor many people l
Page 39 and 40: Overlaying carbon and biodiversityT
Page 41 and 42: Energy to BurnMargaret occupies an
Page 43 and 44: Oceans: SOURCE OF FOOD,ENERGY AND M
Page 45 and 46: Scramble for land:Competing claims
Page 47 and 48: The emerging impactsof rising green
Page 49 and 50: A matter of degrees: Future impacts
Page 51 and 52: Projecting the EcologicalFootprint
Page 53 and 54: Chapter 4:Better choicesfor a livin
Page 55 and 56: SHARE AND SHARE ALIKEA visitor to M
Page 57 and 58: Produce betterEfficient production
Page 59 and 60: ENOUGH FOR ALLNot much goes to wast
Page 61 and 62: Equitable resourcegovernanceEquitab
Page 63 and 64: Closing words:actions from inspirAT
Page 65: Annex 1:The Living Planet IndexWhat
Page 69 and 70: What is included in the Ecological
Page 71 and 72: Table 2: Ecological Footprint data
Page 73 and 74: Annex 3: Glossary of terms andabbre
Page 75 and 76: NationalAccounts ReviewCommitteeNat
Page 77 and 78: Davidson, E.A., de Araujo, A.C., Ar
Page 79 and 80: Thurstan, R.H., Brockington, S. and
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Biodiversity, biocapacity and better choices

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