The missing lynx - restoring Scotland’sThe missing lynx - restoring Scotland’s forgotten catforgotten cat

By Dr David HetheringtonBy Dr David HetheringtonBy Dr David HetheringtonBy Dr David Hetherington

Peter Cairns

ReintroducedPopulations

Natural Populations

European distributionEuropean distribution of Eurasian lynxof Eurasian lynx

Kar

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er

Why consider reintroducing lynx to Scotland?

• Ethical Moral responsibility to restore species that we as humans, made extinct

• Legal The UK is obliged by Bern Convention, Rio Convention & EU Habitats Directive to consider

the feasibility of reintroducing extinct species

• Ecological Restoring top predator to ecosystem may help to reduce damage by deer

• Economic Reducing deer densities can reduce damage to forestry and agriculture. Lynx could contribute to

wildlife tourism

When and how did the lynx become extinct in Scotland, and have conditions improved for lynx since then?

IUCN Guidelines for Re-introductions

“Identification and elimination, or reduction to a sufficient level, of previous causes of decline…”

The distribution of historic and prehistoric remains of

lynx in Britain

Late GlacialLate Glacial

Post-glacialPost-glacial

HistoricHistoric

UndatedUndated

The distribution The distribution of lynx in Europe of lynx in Europe

around 1800around 1800

After Curry-Lindahl (1951) and Kratochvil (1968)

Decline of Forest Cover in ScotlandDecline of Forest Cover in Scotland

• 75% forest cover in mid Holocene

• Permanent deforestation occurred in far north and west 3700-3900 BP due to wetter climate

• Anthropogenic clearance begun by mesolithic communities but occurs on large scale during Bronze and Iron Ages

• >50% of forest cleared by year 1 AD

• Destruction, helped by woodland grazing of livestock, continued until last area of extensive forests, in the Grampians, were all but cleared from 1600-1700

Forest cover by the late 18th Forest cover by the late 18th and 19th centuries for selectedand 19th centuries for selected

European countriesEuropean countries

HungaryHungary 30%30%SwitzerlandSwitzerland 19%19%FranceFrance 14%14%

ScotlandScotland 4% 4%

• 20th Century afforestation means forest cover now 20% for Scottish mainland

• The aim is to have 25% forest cover for the whole of Scotland by 2050, with a focus now on Forest Habitat Networks

Modern ScotlandModern Scotland

• Roe, non-native sika and red deer now widespread and numerous in woodland

• All 3 species occur at high densities, often creating problems for ecology and for forestry

• All 3 species are potential prey for lynx

Study by Breitenmoser & Haller (1993) in the Swiss AlpsStudy by Breitenmoser & Haller (1993) in the Swiss Alpsshowed:showed:

• Lynx at colonising front had much smaller home rangesLynx at colonising front had much smaller home ranges than lynx in the established core distributionthan lynx in the established core distribution

• One male and one female made 75% of their kills in aOne male and one female made 75% of their kills in a 8.5km8.5km2 2 area at the colonising front, while a male and femalearea at the colonising front, while a male and female in the established core made their kills over a 142kmin the established core made their kills over a 142km2 2 areaarea

• Local chamois population at the front decreased from Local chamois population at the front decreased from 800-300 within 6 years800-300 within 6 years

4281333713

111111

Prey speciesNumber

of kills found%

of prey items

Roe deerChamoisRed foxBrown hareMarmot Pine martenBadgerDomestic cat Wild catCapercaillie

69.321.5

6.02.00.20.20.20.20.20.2

Prey spectrum of lynx in the Swiss JuraPrey spectrum of lynx in the Swiss Jura(from Jobin (from Jobin et alet al., 2000)., 2000)

Sheep production Sheep production in Scotlandin Scotland

• High densities in southern Scotland, but low densities in the north and west

• Vast majority of sheep now grazed in open pasture

0

50

100

150

200

250

1999 2000 2001 2002 2003 2004 2005

Nu

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er o

f sh

eep

kil

led

Lynx depredation on sheep in Lynx depredation on sheep in SwitzerlandSwitzerland

Peter Cairns

Peter Cairns

• The extinction of lynx in Scotland was not caused by climate change, and probably occurred during the Middle Ages

• Early and severe deforestation, a decline in deer populations and persecution due to predation on woodland-grazed livestock are likely to have been the most significant factors

• These factors no longer operate in the modern Scottish landscape

How many lynx could Scotland support?How many lynx could Scotland support?

Analysis of HabitatAnalysis of Habitat

• Conducted using a Geographical Information System or GIS

• Most habitat data was drawn from the Swiss Alps due to the high quality of data available and the environmental similarity to much of Scotland.

• 45-74 km2

• 74-550 km2

• 550 km2 +

One female territory only

At least one male and one female

Could support >20 lynx

Total area = 366.7 km2

Total area = 3,172.4 km2

Total area = 17,139.3 km2

100km

Connectivity AnalysisConnectivity Analysis

Northern Scotland

14,994.4 km2

Southern Scotland

5,327 km2 (6,144.4 km2

if including Kielder Forest)

Scotland Scotland

20,321.4 km2

100km

Lynx 100km-2

Source area Ungulates km-2

Ungulate biomass available to

lynx (kg km-2)

Central Norway

Swiss Jura

Swiss Alps

Bialowieza, Poland

Scottish Highlands

Southern Uplands

0.2 roe, 1.6 reindeer, 0.8 sheep 142 0.3

7.2 roe, 1.6 chamois 192 1.0

7.7 roe, 5.0 chamois 289 1.7

4.7 roe, 6.4 red deer 517 2.9

7.4 roe; 3.1 red deer; 1.6 sika, 0.1 fallow 453 -

5.5 roe; 0.9 red deer; 0.1 fallow 183

Wild ungulate biomass and lynx densities from selected areas in Europe

The relationship between lynx density and wild ungulate density for four areas in Europe.

Ungulate biomass kg km-2

Lyn

x 10

0km

-2

Highlands

394 lynx

Southern Uplands

51 lynx

Scotland totalScotland total

445 lynx

Average lynx populationdensities of 2.63 and 0.83100 km-2 are predicted forthe Highlands and Southern Uplands respectively.

Giving:

100km

Population Viability Analysis (PVA)

• Used RAMAS/age software

• Model employed good quality life history data from real lynx populations across Europe

What is the Minimum Viable Population (MVP) size for lynx?What is the Minimum Viable Population (MVP) size for lynx?

• The risk of extinction during 100-year period after reaching carrying capacity was explored for a range of theoretical population sizes

• An extinction risk of 5% or less was considered acceptable

Population Pessimistic Intermediate Optimistic

50 35.6 66.0 84.4

100 76.8 90.4 95.8

150 85.8 93.0 97.4

200 90.8 96.6 97.4

250 90.8 97.0 98.2

300 93.4 96.8 98.6

350 92.0 97.0 98.2

400 96.0 98.2 99.0

450 93.4 97.6 99.0

500 95.0 96.8 98.4

550 97.0 96.6 97.2

600 96.0 98.4 99.0

Probability of persistence over 100 years for a range of population sizes at carrying capacity

100km

Highlands - 394 lynx - VIABLE

Southern Uplands - 51 lynx – NON- VIABLE

Average lynx population predicted for the Highlands and Southern Uplands:

Andreas Ryser

Wildlife corridor – for lynx

ConclusionsConclusions• Lynx are native to Scotland, but humans made them extinct by the late Middle Ages

• Large amount of well-connected potential habitat available

• High densities of prey suggest habitat could support around 450 lynx in two populations

• A Southern Uplands population must be connected to the Highlands population

• The Highlands could support a viable lynx population

Acknowledgements

• Dr Martyn Gorman, University of AberdeenDr Martyn Gorman, University of Aberdeen

• The Highland Foundation for WildlifeThe Highland Foundation for Wildlife

• KORA Carnivore Research, SwitzerlandKORA Carnivore Research, Switzerland

• NorthshotsNorthshots

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