Unsuspicious immigrant or ecological threat

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Unsuspicious immigrant or ecological threat: a long-term fieldwork study on the introduced raccoon in Germany Working Group Wildlife Research (Tharandt) Technische Universität Dresden (chair of forest zoology) ECM Stockholm 2015 Berit Michler R.Vitt

Transcript of Unsuspicious immigrant or ecological threat

Page 1: Unsuspicious immigrant or ecological threat

Unsuspicious immigrant or ecological threat:a long-term fieldwork study on the introduced raccoon in Germany

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

R.Vitt

Page 2: Unsuspicious immigrant or ecological threat

• raccoon settlement and currentsituation in Germany

• applied research on raccoons:

„Projekt Waschbär“ topics of research

selected results

Outline

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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I. Bartussek

• class: mammals

• order: carnivora

• superfamily: musteloidea

• family:

Ailuridae (red panda)Mephitidae (skunks)Mustelidae (weasel family)Procyonidae (procyonids) 6 genus, 13 species

Taxonomy

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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I. Bartussek

Taxonomy

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Zeichnungen: Priscilla Barret

raccoons 1 genus (Procyon), 3 species

Procyon lotor Procyon cancrivorus Procyon pygmaeus

Taxonomy

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

(Hunter & Barrett 2012)

ECM Stockholm 2015Berit Michler

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19291954

1941 1962

Geographic range

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Geographic range

1934

1945

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

Geographic range

I. Bartussek

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

1930 1950 1970 1990 2010

shot

ani

mal

s /

year

Hunting bag development in Germany

1934: first documentedsuccesfull abandonmentin north-Hesse (Edersee)

1954: hunting startsin Germany

ECM Stockholm 2015Berit Michler

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Characteristics

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Characteristics

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)Mikulov, 5.3.2015

Berit Michler

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Characteristics

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Characteristics

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

I. Bartussek

ECM Stockholm 2015Berit Michler

Page 13: Unsuspicious immigrant or ecological threat

Characteristics

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Current situation in Germany

- raccoons are indigenous according to the Federal Nature Conservation Act (BNatschG §5)

- controversial and highly emotional discussion concerningthe impacts of raccoon settlement in Germany

- raccoons are expected to beproblematic:

3 levels of impact

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

I. Bartussek

ECM Stockholm 2015Berit Michler

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Current situation in Germany

I. Bartussek

I. BartussekI. Bartussek

• economic effects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 16: Unsuspicious immigrant or ecological threat

Current situation in Germany

I. Bartussek

I. Bartussek

• economic effects

• hygienic relevance

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 17: Unsuspicious immigrant or ecological threat

Current situation in Germany

I. Bartussek

I. BartussekI. Bartussek

• economic effects

• hygienic relevance

• ecological effects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Current situation in Germany

- better founded knowledge is essential in order to evaluate potential impacts

lack of knowledge

- raccoons are still among the least investigated carnivores in Europe

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Research on raccoons in Germany

4 research studies Society for Wildlife and Nature

Conservation (GWN)

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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Research on raccoons in Germany

Solling

Bad Karlshafen

Kassel

Müritz National Park

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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„Projekt Waschbär“ – Müritz National Park

R. VittR. Vitt

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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„Projekt Waschbär“ – study area

• optimal habitat for Central Europe

• highest density ever messured in Europe for a natural habitat until now (6-8 individuals/km²)

R. Vitt

• area under investigation: 60 km²

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 25: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 26: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 27: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

5. population density(capture-mark-recapture, camera traps)

„Projekt Waschbär“ – topics of research

R. Vitt

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 28: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

5. population density(capture-mark-recapture, camera traps)

6. population structure(structure of age groups, sex ratio, phenotypic characteristics)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 29: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

5. population density(capture-mark-recapture, camera traps)

6. population structure(structure of age groups, sex ratio, phenotypic characteristics)

7. epidemiology & death investigation(histo-pathologic & serologic tests)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 30: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

5. population density(capture-mark-recapture, camera traps)

6. population structure(structure of age groups, sex ratio, phenotypic characteristics)

7. epidemiology & death investigation(histo-pathologic & serologic tests)

8. landscape genetics(impacts of spacial movement patterns)

„Projekt Waschbär“ – topics of research

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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„Projekt Waschbär“ – data basis

VHF- telemetry

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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VHF- telemetryexpandingradio-collars

R. Vitt

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

„Projekt Waschbär“ – data basis

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march 2006 – november 2011:

- 489 raccoon captures

145 different individuals

69 fitted with radio-collars (23 ad. ♀; 28 ad. ♂; 18 juveniles)

- 31.193 localizations (12.931 by day, 18.262 at night)

- 24.959 pictures from camera traps (5365 trap nights)

„Projekt Waschbär“ – data basis

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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• nearly all animals in the study area undertelemetric control

• accurately defined kinship relations throughmoleculobiological analyses(highly variable microsatellites)

„Projekt Waschbär“ – data basis

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 35: Unsuspicious immigrant or ecological threat

1. spatial use(home-range sizes, den sites, habitat use, dispersal behaviour)

2. feeding ecology/parasitology(food spectrum, endoparasite infestation)

3. social behaviour(interaction analysis, relationships, ethology of mother families)

4. reproduction biology(mating- and cubbing season, litter size, parentship, MHC-dependant mate selection)

5. population density(capture-mark-recapture, camera traps)

6. population structure(structure of age groups, sex ratio, phenotypic characteristics)

7. epidemiology & death investigation(histo-pathologic & serologic tests)

8. landscape genetics(impacts of spacial movement patterns)

„Projekt Waschbär“ – selected results

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 36: Unsuspicious immigrant or ecological threat

- main area of interest: what do the animals live off and doesthis affect indegenious species?

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

„Projekt Waschbär“– doctoral thesis

Page 37: Unsuspicious immigrant or ecological threat

- common feeding analysis are not sufficient for statementsconcerning the local ecological impact of raccoons

Foto: R. Vitt

„Projekt Waschbär“– doctoral thesis

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 38: Unsuspicious immigrant or ecological threat

- common feeding analysis are not sufficient for statementsconcerning the local ecological impact of raccoons

doctoral thesis: quantifying of data and intersection with localoffer (n=1285 samples from the Müritz National Park)

Foto: R. Vitt

„Projekt Waschbär“ – doctoral thesis

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

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B. procyonis identificationfeeding ecology

feces from latrines

feces from captured animals

analysis of food contentconversion

factor

feeding trials

parasite eggs

A) feeding ecology investigation

B) determination of a raccoon-specific conversion factor basedon feeding trials

C) scat analysis in respect ofBaylisascaris procyonis

„Projekt Waschbär“ – doctoral thesis

n=1285 fecal samples

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 40: Unsuspicious immigrant or ecological threat

B. procyonis identificationfeeding ecology

feces from latrines

feces from captured animals

analysis of food contentconversion

factor

feeding trials

parasite eggs

A) feeding ecology investigation

B) determination of a raccoon-specific conversion factor basedon feeding trials

C) scat analysis in respect ofBaylisascaris procyonis

„Projekt Waschbär“ – doctoral thesis

n=1285 fecal samples

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 41: Unsuspicious immigrant or ecological threat

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

„Projekt Waschbär“ – feeding ecology

- first results only relate to the rates of occurrence biomass data remaining (even more informative)

- fecal samples (n=1285) were collected from 90 different latrines between 2006-2011

ECM Stockholm 2015Berit Michler

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„Projekt Waschbär“ – feeding ecology

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

34%

22%

44%plants

vertebrates

invertebrates

Müritz National Park (n=1285)

ECM Stockholm 2015Berit Michler

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„Projekt Waschbär“ – feeding ecology

Naturfotografen-forum.de

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

43%

29%

2%0%

26%

insects

molluscs

crayfish

others

earthworms

invertebrates (n = 1232; 44 %)

ECM Stockholm 2015Berit Michler

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„Projekt Waschbär“ – feeding ecology

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

37%

41%

6%

15%

1%

fruit

fruit of trees

nuts

corn

others

plants (n = 961; 34 %)

ECM Stockholm 2015Berit Michler

Page 45: Unsuspicious immigrant or ecological threat

„Projekt Waschbär“ – feeding ecology

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

21%

47%1%

19%

12%

0%

birds

amphibians

reptiles

fish

small mammals

others

vertebrates (n = 613; 22 %)

ECM Stockholm 2015Berit Michler

Page 46: Unsuspicious immigrant or ecological threat

„Projekt Waschbär“ – feeding ecology

- raccoons are omnivorous and have an opportunistic dietary behaviour

they can easily adapt to the localrange of available food

- raccoons are very variable in their diet but prefer food within wetland habitats and foodwhich is easily available in large amounts

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 47: Unsuspicious immigrant or ecological threat

B. procyonis identificationfeeding ecology

feces from latrines

feces from captured animals

analysis of food contentconversion

factor

feeding trials

parasite eggs

A) feeding ecology investigation

B) determination of a raccoon-specific conversion factor basedon feeding trials

C) scat analysis in respect ofBaylisascaris procyonis

„Projekt Waschbär“ – feeding ecology

n=1285 fecal samples

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 48: Unsuspicious immigrant or ecological threat

„Projekt Waschbär“ – feeding ecology

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

conversion factor: proportion of freshweight of food and the dry weight ofthe faeces

how much of the food is finallydefecated? specific value will be a factor in thecalculation of the biomass

- 2 periods: summer & autumn – feeding of 15 different components(concurrent with the food in the wild)

ECM Stockholm 2015Berit Michler

Feeding trials with encountered animals

Page 49: Unsuspicious immigrant or ecological threat

„Projekt Waschbär“ – feeding ecology

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

sample calculation for molluscs:

determined biomass in the sample = 25 %

ECM Stockholm 2015Berit Michler

dry mass = 3,9 g

x 4,74 (calculatedconversion factor)

corrected biomass(freshly consumed) = 18,49 g

Page 50: Unsuspicious immigrant or ecological threat

B. procyonis identificationfeeding ecology

feces from latrines

feces from captured animals

analysis of food contentconversion

factor

feeding trials

parasite eggs

A) feeding ecology investigation

B) determination of a raccoon-specific conversion factor basedon feeding trials

C) scat analysis in respect ofBaylisascaris procyonis

„Projekt Waschbär“ – doctoral thesis

n=1285 fecal samples

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 51: Unsuspicious immigrant or ecological threat

39 %2005

0 %1995

Lux & Priemer 1995

Gey 1998

Gunnesch 2004

Winter 2005

74 %2004

„Projekt Waschbär“ – parasitology

microscope image of an infectousBaylisascaris procyonis egg (size 50 µm)

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39 %2005

0 %2014

Lux & Priemer 1995

Gey 1998

Gunnesch 2004

Winter 2005

74 %2004

„Projekt Waschbär“ – parasitology

current investigationfrom n=400 faecessamles from theMüritz National Park

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Current situation

I. Bartussek

I. BartussekI. Bartussek

• economic effects

• hygienic relevance

• ecological effects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 54: Unsuspicious immigrant or ecological threat

Current situation - economic effects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

- occasionally costly damages toprivate house and garden

ECM Stockholm 2015Berit Michler

Page 55: Unsuspicious immigrant or ecological threat

Current situation - economic effects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

- occasionally costly damages toprivate house and garden

no appreciable economiceffects (e.g. crop damages)

ECM Stockholm 2015Berit Michler

Page 56: Unsuspicious immigrant or ecological threat

- no host animal for fox tapeworm and trichina

- does not play a major role in the europeanepidemiology of rabies (VOSS et al. 2012)

- no important vector of scabies

- can be a carrier of canine distember viruses (CDV) (Rentería-Solís et al. 2014)

- only known considerable zoonosis: raccoon roundworm

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

Current situation - hygienic relevance

epidemiological status in Europe:

ECM Stockholm 2015Berit Michler

Page 57: Unsuspicious immigrant or ecological threat

- no host animal for fox tapeworm and trichina

- does not play a major role in the europeanepidemiology of rabies (VOSS et al. 2012)

- no important vector of scabies

- can be a carrier of canine distember viruses (CDV) (Rentería-Solís et al. 2014)

- only known considerable zoonosis: raccoon roundworm

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

Current situation - hygienic relevance

epidemiological status in Europe:

low estimated epidemiologically risk in Germany

ECM Stockholm 2015Berit Michler

Page 58: Unsuspicious immigrant or ecological threat

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

- so far no serious predation pressure verifiable

- a threat of autochthonous species is not looming ahead

- local negative effects, especially in suboptimal habitats, cannot be ruled out

Current situation – ecological effects

ECM Stockholm 2015Berit Michler

Page 59: Unsuspicious immigrant or ecological threat

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)

- so far no serious predation pressure verifiable

- a threat of autochthonous species is not looming ahead

- local negative effects, especially in suboptimal habitats, cannot be ruled out

Current situation - ecological effects

all current scientific studiesindicate no serious ecologicalimpact for close to naturehabitat

ECM Stockholm 2015Berit Michler

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- research will be finished in 2016

- currently 3 sub-projects in process

„Projekt Waschbär“ – prospects

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 61: Unsuspicious immigrant or ecological threat

www.projekt-waschbaer.de

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler

Page 62: Unsuspicious immigrant or ecological threat

Thank youfor your attention

I. Bartussek

Working Group Wildlife Research (Tharandt)Technische Universität Dresden (chair of forest zoology)ECM Stockholm 2015

Berit Michler