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THE CONSERVATION OF THE RED SQUIRREL IN ITALY
PROGETTO LIFE+ EC-SQUARE ROSSOSCOIATTOLO
Bertolino Sandro & Task Force EC-SQUARE
Università di Torino
• European red squirrel Sciurus vulgaris
• The only native squirrel in most of Europe
• Common in forested areas
• American grey squirrel S. carolinensis
• From north America
• Ecology and behaviour similar to the European species
The Actors of this story
A Conservation Issue: in UK and Ireland the grey squirrel is outcompeting the native red squirrel to extinction
The red squirrel is nearly extinct in England and Wales and at
risk in Scotland and Ireland
A Conservation Issue: The red is also
losing in Italy!
The red squirrel went extinct in an area of about 1700 km2
In red: Red squirrel distribution area in Piedmont
In grey: Area occupied by grey squirrels where
reds have gone extinct
Dotted line: border of the grey squirrel
distribution area
0
50
100
150
200
250
1970 1980 1990 2000 2010
Are
a o
f o
cc
up
an
cy (
gri
d c
ell
s)
Years
Reds
Greys
The red is also losing in Italy! It went extinct in an area of about 1,700 km2
Bertolino et al. Biological Invasions (2014) 16:53–62
From 1970 to 2010 Red squirrel went extinct in 62 % of 2x2km2 (ca. 1,689 km2)
Grey squirrel in South Europe 2096 Based on a predictive model
France
Switzerland
Bertolino et al. Biol. Cons., 2008 Bertolino et al. 2008. Biological Conservation 141: 2564-2575
European projections of grey squirrel’s climatic niche calculated
in Maxent using records from native and invasive range. Map taken from the results presented in Di Febbraro et al. 2013. PLoS ONE 8(7):
e66559. doi:10.1371/journal.pone.0066559
After 3 Recommendatios from The Bern Convention calling Italy to action (78/1999, 11/2005, 123/2007) The 28th Standing Committee of the Bern Convention (2008) opened a ‘case file’ on Italy
A European ‘Case file’ against Italy
In the ECSQUARE project we will develop methods to remove grey squirrels in different socio-ecological contexts. We have to consider:
Aim of the project
• Pubblic opinion (i.e. human dimension)
• Ecology of the species and how to remove the animals (field work: e.g. trappability at low densities)
extermination
The grey squirrel: a cute and charismatic species
Managing introduced species we must struggle against ...
Walt Disney and associated imagery!
We produced a Communication Action Plan with a main message:
The red is our squirrel
The red squirrel is threatened
We have to save our species
To save the reds, we have to control the
greys
• 91 meetings with Stakeholders
• 57,000 visit to the web site
• 100,000 contacts on facebook
• > 200 article on newspapers and magazines
• 1 Video
• 30.000 copies of a Brochure
• > 3,000 students involved
Communicate and …..mediate
Attività di opposizione al progetto
Raccolta firme Interpellanza
CAMERA
INTERROGAZIONI
Consiglio Regionale Lombardo
Consiglio Regionale Piemontese
Consiglio Regionale Ligure
Petizione al
Parlamento Europeo
Manifestazioni in parchi urbani
3 Ricorsi
al TAR Interpellanza
SENATO 2 Commissione
Ambiente
Provincia di
Milano
Richieste accesso agli atti
Lombardia
Piemonte
Liguria
Province
Parchi
Mail bombing 2 Ricorsi
al CdS
Danneggiamenti delle trappole
Opposition to the project
Prevention: banning the grey squirrel from Italy
Grey squirrel management actions were linked with the population size and the extent of the distribution area at a given grey squirrel site
Lombardy: many populations that can be managed independently Eradication with live-trapping and euthanasia Piedmont: a single very large population long-term control with live-trapping and euthanasia Liguria: a small population in an urban park eradication with live-trapping and surgical sterilization
Methods and strategies
In year 2013, trading, raising and keeping of grey squirrel and other two squirrel species (Sciurus niger, Callosciurus erythraeus) has been forbidden in Italy
Prevention: Banning alien squirrels form Italy
Grey squirrel in Lombardy
Areas where alien squirrels are recorded
We are working in four of these areas
Take home message from Lombardy
Grey squirrel eradication is possible, And this will bring reds back!
Piedmont
Control aims to stop further spread of the alien species in Piedmont and toward neighbouring countries and to protect red squirrels populations
Large expansion of the grey squirrel in Piedmont > 2000 sqkm in the Po Plain and hills, with reduced forest cover
• Maintain red squirrel in strongholds (large forests in the plain between Turin and Cuneo) • Removing grey squirrels in private parks of historical estates
In Piedmont we are collecting information for a long-term grey squirrel control plan
Pushing back grey squirrels expanding along rivers to maintain red squirrels in these ecological corridors
In most of the grey squirrel’ area the forest cover is greatly reduced and private parks are strongholds for the species
Removing grey squirrel in private parks of historical estates
In these areas (with high local densities 10-20 squirrels/ha) the sub-populations could be removed in a few weeks
Pushing back grey squirrels expanding along rivers
Checking for grey squirrels that
passed the barrier
R² = 0,9168
0
1
2
3
4
5
6
7
8
9
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Tra
pp
ed
sq
uir
rels
Trapping weeks
Grey squirrel barrier
(trapping and
removal)
Red squirrels
removed by
grey squirrels Grey squirels
removed by
humans
Euthanasia of squirrels ... a comparison
In particular situations, such as Genoa Nervi park inside urban areas, where the public is accustomed to see and feed the grey squirrels, a removal method that implies killing the animals may not be accepted, carrying to a strong opposition to the whole project. In these situations, with small populations, the eradication with surgical sterilisation should be considered a possible alternative.
Liguria: a new approach to reduce conflict
The solution proposed to the Stakeholders: 1.Live-trapping
2.Surgical sterilization
3.And….
Maintain in captivity
Release in other urban parks of the city
Release on a island
ADAPTIVE MANAGEMENT
Grey squirrels at Genoa Nervi
Visual census
Distance sampling
Toward the eradication at Genova Nervi
Removed in the
park at Nervi
0
5
10
15
20
25
30
35
Squ
irre
ls r
em
ove
d /
15
day
s
Female
Male
Squirrels removed from Genoa
Totally removed: 322 squirrels
• Park of Nervi 309
• Other areas 13
Sterilization: how much does it cost?
Planning Live-trapping Transportation to
the clinic
Surgical
sterilization
Release Monitoring and
supporing
released animals
Monitoring
eradicated area
Euthanasia
Surgical sterilization
Effort (cost)1.9-2.4
more
100 €/squirrel
30.000 euro
Animals removed in accordance with the
availability of the clinic to operate
11 11
14
21
26 25
0
5
10
15
20
25
30
Area A 49 squirrels Area B 68 squirrels Area C 57 squirrels
Tra
pp
ing
eff
ort
(d
ays
)
Squirrels removed
Removal effort with livetrapping and Euthanasia or Sterilization
Euthanasia
Neutering
Sterilization: how much does it cost?
Planning Live-trapping Transportation to
the clinic
Surgical
sterilization
Release Monitoring and
supporing
released animals
Monitoring
eradicated area
Euthanasia
Surgical sterilization
Effort (cost)1.9-2.4
more
100 €/squirrel
30.000 euro
Animals removed in accordance with the availability
of the clinic to operate (generally 4-5/day)
Eradication trial
47 squirrels removed in 1 day
188 squirrels removed in 8 days
Not possible with neutering !!
Take home message from Liguria
Prepare a management plan, but consider also some alternative options if the initial position is too strongly fought.
However, be clear and firm about what can not be changed.