Transcript Important Considerations for Intensive Management of Endangered

Important Considerations for Intensive
Management of Endangered Species
 Often managers rush into intensive
management for a quick, high profile fix of
a declining species
 Before captive propagation, reintroduction,
and translocation are considered four
general areas should be addressed (Kleiman et
al. 1994)
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Condition of the Species
Environmental Conditions
Biopolitical Considerations
Biological Knowledge
Removing the Cause of Decline
 This is really the crux of endangered species
conservation
 Requires detailed observation and likely
experimentation to fully understand reason for
decline
– Brown tree snake was not immediately recognized
– Condor limiting factors required telemetry to ID
• not 1080, not disturbance at nest, not shooting,
likely lead poison because Condors need open
habitat to find food and hunters/ranchers common
there
Facing the Evil Quartet
 Typically we are up against
– habitat destruction/degradation
– exotics
– trophic cascades
– overharvest
– contaminants
 Contaminants and overharvest are easiest to
remove or reduce
Recovery after Agent of Decline
Removed
 Stop Over harvest
– whales, alligator
 Remove Pesticides
– Peregrine, Bald Eagle, Brown Pelican
 Remove Pesticides and Modify Habitat
Needs
– Mauritius Kestrel (Jones et al. 1991)
• 1974-----4 birds
• 1991-----127-145 birds
Exotics are Very Difficult to
Control
 Disease, Snakes
– Technology not adequate to control
– Buy time by “marooning” (Williams 1977)
• release small numbers of species with poor dispersal
ability in isolated habitat (typically islands)
• 700 islands off New Zealand
– Saddleback, Kakapo (flightless parrot), Takahe (Rail)
• Buys time until feral introduced mammals can be
removed
• Guam Rail released on Rota
Are We Treating the Symptom or
the Cause of the Problem?
 Often rush into captive propagation without
addressing limiting factor
– “Headstarting” Sea Turtles (Tate 1990)
• rear until old enough to avoid predation on nesting
grounds
• Better to protect nesting ground
– Hatcheries and barges for Salmon
• damns, habitat loss, fishing, etc are cause
– May be justified to learn about propagation and
control
• Mariana Crow
A Complex Example of
Addressing Limiting Factors
 Rhinos in Africa
http://gurukul.ucc.american.edu/Ted/RHINOBLK.HTM
 Destruction of habitat, hunting, illegal trade in
products (folk medicine, dagger handles)
– reduction in numbers from 65,000-100,000 in 1960s to
~3,000 today
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regulations (CITES)
scientific study of medicinal effects
Leader of Yehman using agate handle dagger
shoot to kill poacher policy
De-horning
Ranching to flood market
Little Progress with Rhinos
 Can’t change old beliefs quickly
– medicinal effects of horn
 Value of horn in poor countries makes risk of
death worth it
 De-horning not very effective
(Berger 1998, Rachlow
and Berger 1997)
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grow back (possible sustainable harvest?)
killed out of spite
even small portion of horn near skull valuable
dehorned mothers less able to defend calfs from hyenas
 Need to work at both ends of trade routes
Hope with One-horned Rhinos
(Dinerstein 2003)
 Rhinos in India-Nepal are increasing with creation
of Royal Chitwan National Park
– Community pride, ecotourism, natural resource benefits
to residents, Royal family of Nepal leadership
 General approach
– Design landscapes with large, protected cores
– Introduce powerful economic incentives, legislation,
awareness
– Identify bold leadership to rally political will
• Translocation
• Redistribution of park revenue to locals
• Resettlement or land transfer
How Do We Protect or Restore
Enough Habitat?
 Biopolitical Considerations (Kleiman et al.
1994)
– No negative impact for locals
– Community support exists
– GOs and NGOs supportive/involved
 But what about when there is an obvious
Economic Cost?
– Especially when habitat is already being used
by humans
• Salmon
Captive Breeding and Reintroduction
 Once the limiting factors have been
addressed it might be time for intensive
management
– last resort
– expensive
– difficult to make succeed
• Beck et al. 1994-- 11% successful
• Griffith et al. 1989-- 19% successful
– requires large, long-term effort in captivity and
the wild
Typical Questions About Captive
Propagation
 Is it necessary?
 Is it successful and worth it?
 How do you do it?
– Technical questions about breeding, rearing,
and release
Intensive Management Programs
are Complex
Example from Mariana
Crow program on Guam
•landowner coordination
•monitoring
•pull eggs
•rear nestlings
•translocate
•hack to the wild
•control predators
Why Captive Breed?
 Produce stock for reintroduction (Wilson and
Stanley Price 1994)
 Preserve genetic variability
 Produce stock for research
 Produce animals for public education
 Provide insurance against extinction
– alala pva
What are We Breeding in
Captivity?
 (Ginsberg 1994,
Canids)
 Reviewed species bred
in captivity (N = 32)
from 1971-1990.
3 endangered species account
 Most are common
for 95% of litters for V&E
species
species (Maned Wolf, Af. Wild
Dog, and Bush Dog)
 Increase in vulnerable
75% of all captive breeding is
and
endangered
done on 3 species (grey wolf,
species in late 1980s
red fox, dingo)
Criteria to Meet Prior to
Reintroduction (Kleiman et al. 1994)
 Already discussed environmental and
political considerations
 Condition of the species
– Is there a need to increase numbers,
populations, or genetic diversity of the species?
– Is appropriate stock available?
– Will introduction jeopardize wild population?
Criteria to Meet Prior to
Reintroduction (Kleiman et al. 1994)
 Biological and Other Resources
– Do we know how to rear and reintroduce the
species?
– Do we know enough about the biology of the
species to determine if we have been
successful?
– Is funding for the long term available
• includes monitoring success of reintroduction
Example of Meeting Criteria for
Tamarins (Kleiman et al. 1994)
Condition of species
1. Need to augment wild pop.
2. Available stock
3. No jeopardy to wild pop.
Environmental conditions
1. Causes of decline removed
2. Sufficient protected habitat
3. Unsaturated habitat
Biopolitical conditions
1. No negative impacts for locals
2. Community support exists
3. GOs/NGOs supportive/involved
4. Conformity with laws/regulations
Biological or other resources
1. Reintroduction technology known
2. Knowledge of species' biology
3. Sufficient resources exist for program
Recommend reintroduction/translocation?
Golden
Golden
-headed
Yes
Yes
?
No
Yes
?
?
Yes?
Yes
No
No
Yes?
No
5
Yes
Yes
?
2
Yes
?
4
5
Yes
Yes
3
1.4
No
No
Assessment of Reintroduction
Projects (Beck et al. 1994)
% of Projects
Character
Pre-release training
Acclimatization
Medical Screening
Genetic Screening
Post-release training
Provisioning
Local Employment
Professional Training
Community Education
Release Years
Monitoring
All
35
76
46
37
12
63
53
56
70
6.5
96
Mammals
36
82
60
35
12
69
50
52
59
3.03
97
Birds
48
83
47
34
19
84
64
64
76
6.09
98
Reptiles
7
56
31
46
0
13
54
54
77
7.5
87
 Reviewed projects from 1900 to 1993
– N=145 projects, 13 million animals of 126 species
– acclimate = hard vs. soft release
What Made Project Successful?
Character
Pre-release training
Acclimatization
Medical Screening
Genetic Screening
Post-release training
Provisioning
Local Employment
Professional Training
Community Education
Release Years
Monitoring
% of projects
Successful
50
75
17
25
8
42
75
58
100
11.8
42
% of projects
Other
32
68
49
35
11
63
47
51
62
4.7
63
 Successful if N=500 w/o human intervention or PVA looks good
 16 (11%) successful
 Training, local involvement, education, and duration are
consistently important
Criteria for Success from Griffith
et al. (1989)
 Type of species (game more successful than
threatened)
 Habitat quality (better success into good habitat)
 Location of release (better in core of historic range)
 Source of stock (Wild caught better than handreared)
 Food habits (herbivore better than carnivore or
omnivore)
 Duration of study (longer and more animals
released increased success)
Size and Persistence of Release
Matters (Ginsberg 1994)
 PVA model results
(Kit Foxes)
N=50
 N=Starting pop size
 SP=successive
N=100
N=500 releases of 20 indiv/yr
for 10 years
 Huge increase in
viability with little
Successive Releases
increase in per year
N=50SP; N=100SP
release effort.
Major Drawbacks to Success
(Snyder et al. 1996)
 Need to maintain a self sustaining captive
population
 Need to successfully reintroduce
 May get domestication and disease in captivity
 Need considerable funds and facilities
 Diverts attention from long-term solution in
the field (easy to do quick fix)
 Need consistent administration (Clark et al.
1994)
The Biology of Captive
Propagation and Reintroduction
 Captive Breeding
– zoo biology and husbandry
 Manipulating Wild Pairs
– pull clutch
 Captive Rearing
– considerations of diet, disease, training
 Reintroduction
– translocation, fostering, hacking (soft release),
hard release
A General Captive Propagation
Program
 Aplomado falcons (Cade et al. 1991)
• bring birds in from captivity
– acclimate so they breed in captivity
– increase productivity by food supplementation and clutch
manipulation
– hand rear young, experiment with parent rearing
• manipulate wild pairs
– clutch manipulation
• hack out captive-reared birds
– meet recovery goal for species
– 30-50 young released for 10-15 years
– require 15 pairs (35 individuals)
How to Incubate Eggs?
 An example of figuring out one aspect of captive
propagation
 Use of surrogate species
 Need controlled experiments
Effects of Manipulating Wild
Pairs
 Bald Eagles (Wood and Collopy 1993)
– 78% renested within 1 month
– subsequent reproduction within the year may be reduced
• this was modeled with RAMAS age model and was estimated
not to affect viability of “donor” population
 Corvids (Marzluff et al. 1994)
– 69% renested
– reduced clutch size on renesting and slightly lower
number of fledglings
– occupancy and productivity at manipulated sites was
same as controls next year
Hand-rearing May Produce
Undersized Young for Release
 Growth is usually faster
in nature and may
produce light-weight
young (magpies)
 Growth in captivity may
be compensatory (crows)
 If dominance is related to
size, then survival or
breeding may be reduced
– Whitmore and Marzluff
1998
Raising Mammals in Captivity
 Hand-rearing diets for
Elk
Big-horn
Pronghorn
wild ungulate neonates
– used ad lib feeding of
evaporated milk
– easy and growth
similar to wild
• Wild et al. 1994.
Practice Makes More Perfect
 Mortality of pups is
reduced with
increasing number of
litters produced for a
species
– 3 outliers were
removed from
analysis??)
– Ginsberg 1994
Ferret Predatory Behavior Is
Influenced by Rearing
Vargas 1994
– % of ferrets that killed PDs at 16.5
weeks
– Group I
• cage-raised, no exposure to live
prey
– Group II
• Cage-raised, exposed to live
hamsters--went for back of
neck, not throat
– Group III
• Cage-raised, exposed to live
Prairie Dogs
– Group IV
• Outdoor raised, exposed to PDs
Survival of Released Foxes is
Affected by Method of Release
 Kit Foxes (in Ginsberg
1994)
Wild Caught,
Hard-release
 Wild caught
translocated (hard
release) did best in
All Soft Releases
short term
All Hard  Hard versus Soft
Releases
Release were
similar after 2
Captive Reared, Hard-release
years
Sometimes Younger is Better!
(Valutis 1997)
 Post-release survival
Assume missing
birds were alive
Assume missing
birds were dead
of American Crows
was better if we
released them young
– less dispersal
– gradual integration into
wild flocks may be
better
– wild birds may be
more receptive to new
birds during breeding
season
References
 Vargas, A. 1994. Ontogeny of the endangered black-footed ferret
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(Mustela nigripes) and effects of rearing conditions on predatory
behavior and post-release survival. PhD. Diss. U. Wyoming
Ginsberg, JR. 1994. Captive breeding, reintroduction and the
conservation of canids. PP. 365-383. In. Olney et al. (eds.). Creative
Conservation. Chapman and Hall, London.
Valutis, LL. 1997. Reintroduction of captive-reared birds. MSc. BSU.
Boise, ID.
Wild, MA. Et al. 1994. Comparing growth rates of dam- and handraised Bighorn sheep, pronghorn, and elk neonates. J W M 58:340347.
Whitmore, KD and JM Marzluff. 1998. Hand-rearing corvids for
reintroduction: importance of feeding regime, nestling growth, and
dominance. JWM 62:1460-1479.
More References
 Wilson, AC and MR Stanley Price. 1994. Reintroduction as a reason
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for captive breeding. PP 243-264. In. Olney et al. (eds.). Creative
Conservation. Chapman and Hall, London.
Kleiman, DG et al. 1994. Criteria for reintroductions. PP 287-303. In.
Olney et al. (eds.). Creative Conservation. Chapman and Hall, London.
Beck, B.B., et al. 1994. Reintroduction of captive-born animals. PP
265-286. In. Olney et al. (eds.). Creative Conservation. Chapman and
Hall, London.
Griffith, B. Et al. 1989. Translocation as a species conservation tool:
status and strategy. Science 245:477-480.
Cade, TJ et al. 1991. Efforts to restore the northern aplomado falcon by
captive breeding and reintroduction. Dodo 27:71-81.
Williams, GR. 1977. Marooning--a technique for saving threatened
species from extinction. International Zoo Yearbook 17:102-106.
Yet More References
 Jones, CG. Et al. 1991. A summary of the conservation management of

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the mauritius kestrel Falco punctatus 1973-1991. Dodo 27:81-99.
Rachlow, JL. And J. Berger. 1997. Conservation implications of
patterns of horn regeneration in dehorned white rhinos. Conservation
Biology 11:84-91.
Berger, J. 1996. Animal behaviour and plundered mammals: Is the
study of mating systems a scientific luxury or a conservation
necessity? Oikos 77:207-216.
Wood, PB. And MW Collopy. 1993. Effects of egg removal on bald
eagle productivity in northern Florida. JWM 57:1-9.
Marzluff, JM et al. 1994.Captive propagation and reintroduction of
social birds. Annual Report. Sustainable Ecosystems Institute,
Meridian, ID.