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1 Oralis Limited, Dunedin, New Zealand. 2 Kiwi Encounter, Rainbow Springs, Rotorua, New Zealand. The artificial incubation of wild laid kiwi eggs – a conservation tool. Suzanne Bassett 1 & Claire Travers 2. J. Newman. Acknowledgements.
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1Oralis Limited, Dunedin, New Zealand 2Kiwi Encounter, Rainbow Springs, Rotorua, New Zealand The artificial incubation of wild laid kiwi eggs – a conservation tool Suzanne Bassett1 & Claire Travers2 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
Ratites • Kiwi • Cassowary • Emu • Ostrich • Rhea • Moa • Elephant bird M. Potter
R. Morris 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. Morris
Kiwi abundance & distribution • 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) Department of Conservation
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 Kiwi Encounter
Incubation challenges High hatch success but… • Cracked eggs • Embryo mortality • Malpositioned chicks assisted hatches S. Bassett & KE
Egg results 2007/08 • 120/171 eggs incubated • (70 % eggs viable) • 106/120 chicks hatched (88 % hatch success) • 1000th ONE chick S Bassett Waikato Times
General conclusions Kiwi Encounter • 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 T. Kelly
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