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The artificial incubation of wild laid kiwi eggs – a
conservation tool
Suzanne Bassett1 & Claire Travers2
2Kiwi Encounter, Rainbow Springs, Rotorua, New Zealand
1Oralis Limited, Dunedin, New Zealand
J. Newman
Acknowledgements• Department of Conservation & all
community trust kiwi projects
• Kiwi Encounter, Rainbow Springs, Rotorua
• Massey University & University of Otago
• Dr Trevor Kelly, Vet Centre, Rotorua
Talk outline
• Kiwi biology• Kiwi decline & threats• Operation Nest Egg• Incubation challenges• Ethical considerations• Kiwi welfare• Summary
Taxonomy • North Island brown kiwi
(Apteryx mantelli)
• Okarito brown kiwi (Apteryx rowi)
• Southern tokoeka (Apteryx australis)
• Haast tokoeka (Apteryx australis ‘’Haast’)
• Great spotted kiwi (Apteryx haastii)
• Little spotted kiwi (Apteryx owenii)
R. M
orris
R. Morris
Kiwi abundance & distribution
Depart
ment
of
Conse
rvati
on
• North Island brown kiwi (25,000)
• Great spotted kiwi (17,000)
• Okarito brown kiwi (250)
• Southern tokoeka (15,000)
• Haast tokoeka (300)
• Little spotted kiwi (1,500)
The kiwi egg & chick
• Egg large relative to body size (20%) (~440 g)
• 1 functional oviduct, 2 functional ovaries
• 2 eggs/clutch, 2-3 clutches/yr (NIBK)1 egg/1 clutch/yr (SI sp)
• High fertility (NIBK)Low fertility (SI sp)
• Male incubation, length ~85 d wild, 78 d art inc
• Highly precocial chicks (~320 g hatch weight)
Otorohanga Zoological Society
Kiwi decline
• All kiwi are endangered
• Adult mortality ranges 5 – 16%/yr- Predators cause 28% mortality
• 50% eggs failed to hatch–10% due to predators
• Rate of decline 6%/yr(McLennan et al . 1996)
Kiwi Encounter
Juvenile kiwi mortality• Juvenile kiwi mortality
94%– Introduced
mustelids kill 77%
• Main predator = STOATS (Mustela erminea)
• Predation declines as chicks grow
Forest & Bird
Tui De Roy
Management responses• Habitat protection
–Public lands – Department of Conservation
–Private lands – Landcare Trust, QE2 Trust, Community programs
• Predator Control- Poisoning, trapping and exclusion fencing of mammalian predators
• Direct management of Kiwi–Captive rearing of wild-laid eggs & chicks (Operation Nest Egg – ONE)
G.L. Blackwell
Department of Conservation
Operation Nest Egg
Kiwi eggs & chicks removed from the wild
Taken to a captive rearing institute for incubation,
hatching & rearing
Chicks raised until 800 g+ & released to wild
Chicks released in predator free area
O.N.E a short term measure to ‘buy time’
Management & animal welfare
• Habitat protection – few ethical issues
• Predator Control- On conservation estate DOC does not require AEC approval for “regular & routine” animal control under Section 5, sub-sect 3a, b, c of Animal Welfare Act 1999
• Direct management of Kiwi–Administered by DOC–ONE also considered “regular & routine” captive management under Animal Welfare Act 1999
Kiwi Encounter
• 1995/96: (1 egg) 2007/08 (171 eggs)
• Egg age 0 – 75 days (2005/06 median 38 days)
• 910 eggs to end of 07/08, 667 eggs viable, 623 chicks released to date
• Forced draft artificial incubation
• Focus on North Island brown kiwi
Kiw
i E
nco
unte
r
Incubation challenges
High hatch success but…
• Cracked eggs • Embryo mortality• Malpositioned chicks
assisted hatchesS. Bassett & KE
Egg results 2007/08
• 120/171 eggs incubated(70 % eggs viable)
• 106/120 chicks hatched (88 % hatch success)
• 1000th ONE chickS Bassett
Waikato Times
General conclusions
• Improvements in O.N.E- hatch success
(40 % to 90+ %)- chick survivorship
pre-release 60 % to 95 %post-release 80+ %
• New techniques: x-rays, advances in candling & incubation, chick rearing and release protocols
Kiw
i E
nco
unte
r
T. K
elly
Kiwi Encounter & animal welfare
• O.N.E
–“Regular & routine” management under Animal Welfare Act 1999
–Ongoing research to improve animal welfare in ONE
• Ways to improve hatching success and chick survival• Egg and chick transportation protocols• Disease management and quarantine protocols
• Approved by DOC and the Kiwi Recovery Group
Kiwi Encounter & animal welfare
• Day to day husbandry
–Hygiene, housing, feeding, health• “Yolk-sac” operations to remove impacted/infected
yolk• Abandoned eggs or chicks
–Development and refinement of best practice
–Responsible to DOC & Australasian Regional Association of Zoological Parks and Aquaria (ARAZPA)
Kiwi Encounter & broader kiwi welfare • Injured birds
– Small numbers of injured kiwi treated by Kiwi Encounter
• Vehicle collisions• Trap injuries• Dog attacks – wild dogs & ‘kiwi’ dog accidents
– Poor public & vet. awareness of standards & responses to injury/harm
Kiwi Encounter
Kiwi Encounter & broader kiwi welfare
• Concerns about impacts of O.N.E on kiwi welfare– Do captive reared kiwi
have lower survival than wild chicks?
• No difference in survival• Earlier breeding attempts
– Is there evidence of stress or harm to captive kiwi
• No imprinting• No evidence of prolonged
stress
Kiwi Encounter
General conclusions – kiwi conservation
• Increased public awareness of kiwi conservation
• Change in perception of O.N.E
• Increased kiwi numbers
• Strategic use of O.N.E - pulsed application by year or by area e.g. stoat eruption S Bassett
Summary• Kiwi continue to decline but…
Captive rearing is making a huge difference
• Urgently require effective stoat control … a long way off
The next step …
• Improve husbandry for other kiwi sp
• O.N.E to recover populations near extinction – eg South Island species
• Continue to follow & improve best practice for husbandry & welfare
• Public education on kiwi welfare
Kiwi Encounter