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Reintroductions
Australian and New Zealand perspectives
Canadian reintroductions
Case studies
The good, the bad and the ugly??
Other issues to consider
Australia
100+ species of plants and animals have gone
extinct in the last 200 yrs
Mammals
25 species extinct
10 species only on islands
17 species in remnant habitat
10% of their pre-European range
Australia
Medium and large species are more
vulnerable to extinction
Fig 1 Cardillo and Bromham 2001
Reintroductions in Australia
Many macropod reintroductions have been
attempted
Success rate
Islands no predators
82%
Mainland/island with predators 8%
Failure attributed to predation
- foxes and cats
Short 1992
Reintroductions in Australia
PREDATOR FREE ISLANDS
Eg
2002
Faure Island Sanctuary, WA
Burrowing bettong
20 released
now 100
2002 Shark Bay Mouse 100 released
now all over island
2005 Banded hare wallaby 16 released
“thriving”
Faure Island 6000 ha
What about the mainland?
Australian Wildlife Conservancy
Triple barrier sanctuaries
Predator control
Predator removal
release
Woylie
Karakamia
Sanctuary
fence
12 km buffer zone
Reintroductions in Australia
Basic premise
Limit the impact of predation
IMPACT = NUMBER X EFFICIENCY
Options Lethal Control
Fertility
Reduce Primary Prey
Eg Flinders Range
Rabbit haemmorhagic disease
Rabbit population down 85%
Fox and cat population down 40%
Limit the impact of predation
IMPACT = NUMBER X EFFICIENCY
Options Pre-release training
Aversion therapy
Enhance refuges
Stokes et al.2004
Wire net
Limit the impact of predation
Refuges from predation
Wire net
Wire net
Giving up densities
Foraging path
Stokes et al.2004
New Zealand
No terrestrial mammals prior to humans
But 245 spp birds 71 % endemic
Early Extinctions
Post-European extinctions
33
19
Cause - exploitation
- invasive spp - 33 mammals
Area of NZ - 27 million hectares
Area not invaded by exotics 2000 ha
Conservation in New Zealand
Step 1
% conservation budget - 40%
Area where exotics eradicated 30,000 ha
Islands > 55 ha: 53 one spp removed
36 free of all introduced spp
Reintroductions in New Zealand
Examples
Black robin
1977: 1 female
1994: 200
Giant weta
2001: 81 released
2003 - producing young
Tuatara
1996-2004
Releases on 4 islands
Number translocations >400
Number animal taxa - 68 +
Reintroductions in New Zealand
Restoration aims
recreate structure, function and dynamics of
original ecosystem
What do you do if keystone spp is extinct?
Norfolk island - 2 extinct pigeons
Chatham Island - extinct parrot
What do you do if keystone spp is extinct?
Consider use of a “functional surrogate”
Reintroductions In Australia and New Zealand
Common tool to
-reduce extinction risk of vulnerable species
-- restore degraded ecosystems
Key factor: removal/control of predators
Why?
Introduced predators are the major cause of
population declines
Exploring reintroductions In Canada
Why?
1) 577 Species at Risk
70% of Recovery Plans consider translocations
2)
Climate Change and possible need to
re-assemble communities
Reintroductions: the good?
Reintroductions: Burrowing Owl
Reintroductions: Burrowing Owl
Population
< 1000 pairs in Canada
declines 22%/yr
Issues - habitat loss
- lack of burrows
- shortage of food
- vulnerability to predators
- migration - fewer refuges
- wintering grounds ??????
Reintroductions: Burrowing Owl
In BC
Attempt 1 1983-1989 Vaseaux/Osoyoos Lake
Wild ct breeding pairs released
in artificial burrow
Produced young
But no birds returned to site
FAILED
Reintroductions: Burrowing Owl
In BC
Attempt 2 1990 - now Thompson/Nicola
Captive breeding
in Vancouver/Kamloops
1 yr old birds released at historical sites
artificial colonies created by volunteers
Reintroductions: Burrowing Owl
Reintroductions: Burrowing Owl
Attempt 2 - owls breed, migrate and return
- population small but increasing
Additional benefits
ongoing research on captive breeding
public outreach and education
landowner support for initiative
modified grazing regimes
improvements to grassland habitat
Reintroductions: Vancouver Island marmot
Numbers in wild
1984 235
1997 102
1998 71
2000 36
Distribution
25 sites on 13 mountains;
67% of animals on 4 mountains
Vancouver Island marmot
Occupy small patches of subalpine meadow
Patches available but no
longer colonized
Issues: logging and clearcuts
predation
disease
climate change
(snowfall/snowpack)
Reintroductions: Vancouver Island marmot
1997-1999 17 removed for captive breeding
1999-2004 38 more removed
2008
4 facilities - 160 animals
Releases
2003 4 (all 1-2 yrs - all dispersed -- >killed)
2004 9 (6 m 3 f; all 2 yrs)
2005 15 (10 m 5 f; all 2 yrs)
A marmot update
2008
total releases = 155
11 litters born
7 litters with 1+
captive parent
A marmot update
2003
Captivity
Wild
77
21
Mountains with
Marmots
4
Possible pairs 3
2008
162
102
17
17+
Summary
Reintroductions
Are an increasingly common tool
Are successful if the cause of declines are
known and eliminated/reduced
Are less successful if the reasons for declines
are uncertain
Genetic issues in reintroductions
1. Where do we get individuals from?
Natural selection ---> local adaptation
To far away ---> hybridisation/outbreeding
depression
2. How many founders are needed?
Too few --> low genetic diversity and
inbreeding depression?
Practical issues in reintroductions
How and whom to release?
Soft or hard introductions
Age/number/relationships of individuals