Kori Bustard Husbandry
Sara Hallager, Biologist, Smithsonian National Zoological Park • Ardeotis kori • 2 subspecies [?] • Africa’s largest flying bird • Captive males: 12-19kg – Seasonal weight gain up to 4kg • Captive females: 6-7kg
Status in the Wild • Habitat declining • Illegal hunting • Naturally low reproduction • Reduced breeding in dry years • Population numbers unknown • Species is declining
Bustards Kept in US Zoos
Three species in US zoos • Kori bustard* • White-bellied bustard • Buff-crested bustard* Koris in US Zoos • In US collections since 1940 • Breeding > 1992 – 150 chicks born • AZA SSP© population since 2000 • International Studbook [>700 birds historically] • Currently ~60 birds in US
Genetics of US Population
Current Potential Founders 13 8 more
Founder genome 6.24 18.87 equivalents Gene diversity retained 0.92 0.974
Population mean 0.08 0.026 kinship Disposition
Shy birds, easily disturbed by human activity
High crowd levels can negatively affect behavior
Need ample places to hide
Males more likely to show reproductive behavior
Non-aggressive to other species – best exhibited alone to promote breeding
Husbandry issues
• General trauma [usually fatal] • “Hardware disease” • Limited reproduction • Survivability of young birds • Diet • Flighty species, easily stressed by human interactions
Feeding
• Strive to feed an omnivorous diet, limit mice • Mix pellets with meat • Free choice pellet feeders • Offer as many insects as can afford • Feed twice a day • Enrichment important Kori Bustard Recommended Diet [AZA kori bustard Animal Care Manual]
Minimum % Item Maximum % of Diet of Diet
Vertebrate prey 0 25 Invertebrate prey 5 30 Nutritionally complete feeds* 40 55 Produce 10 20
* Mazuri gamebird, Zeigler Ratite, Zeigler Crane Breeder, NARC Production Pellet, Mazuri Ratite, Zeigler Avian Maintenence Kori Bustard Recommended Diet [AZA kori bustard Animal Care Manual]
Invertebrates Diet Vertebrate Prey (Crickets) gut Nutritionally Complete Foods Produce loaded
35% (Zeigler Avian 1 25% (mice) 25% 15% Maintenance1)
40% (Mazuri Waterfowl 2 15% (mice) 25% 20% Maintenance2)
55% (Zeigler Ratite 3 0% 25% 20% Grower/Maintenance1)
55% (Mazuri Exotic Gamebird 4 20% (mice) 25% 0% Maintenance2) Survivability • 150 chicks born since 1992..only 50 still alive • First-year mortality is high: 32% for males and 41% for females • Mortality rates stay high throughout lifetime ~10% per year [females tend to live longer]
• Breeding currently limited to a few birds that produce numerous offspring – only way to maintain demographics • Many captive hatched birds not surviving to the average age of first reproduction o ~1/3 die before reaching 1 year. o ~75% of the captive born die before reaching 10 years • Why? – Self-inflicted injuries – leading cause – Cage mate aggression – Other….. Kori bustard Mortality Buff crested bustard
• 130 hatches since 1988 • Less accident prone than koris, fewer medical problems? • Handreared birds can be a problem for breeding • Potential model for other small bustard breeding programs
Buff-crested bustard Mortality
First-year mortality: 39%♂, 25%♀ Mortality rates throughout life high for ♀s
Housing • Species best housed alone – Breeding – Aggression from other species • Adult males are incompatible! – ok until ~3 yrs • Recommended sex ratio: 1♂:2-3♀ • Females can be aggressive to each other Enclosure Parameters • No trip hazards • At least 8’ high fence • Ample hiding areas • Flat ground/grass • Areas of sun/shade/sand • Hot-wired/covered • Winter housing needed • Wet climates bad for bustards • Natural foraging options
Capture Things to know….. 1. Males are very powerful 2. Bustards have thin skin, easily torn 3. Inherent nature to shed feathers 4. Highly sensitive to stress
Capture • Do not use nets! • Walk bird into a shed – Hand catch • Hood vs. no hood • Hand carry or crate • Keep handling time to a minimum • Catch in the AM • Handler safety
Weight Monitoring Weights
• Chicks from day 1 • Birds are trained to step on a scale • Adults weekly or monthly • Breeding males gain up to 4kg • Females no change • Good way to monitor health of birds, breeding season start up
30000 25 Testosterone Weight
25000 20
20000
15
Weight (kg) Weight
15000
10 Testosterone (pg/g Testosteronestool) (pg/g 10000
5 5000
0 0 Jan-04 Mar-04 May-04 Jul-04 Sep-04 Nov-04 Jan-05 Mar-05 May-05 Jul-05 Sep-05 Nov-05
Testosterone and weight changes in a male kori bustard at the Smithsonian’s National Zoo Breeding Strategy in the Wild
• Dispersed lek • Females visit lek for copulation • Female incubates eggs and raises chicks • Chicks stay with dam for > 1 year • Male plays no part in chick rearing • Solitary – Form small groups during non-breeding season • Females stay in natal area / males disperse
Breeding in
US zoos • 1♂:2-3♀ • Not all ♀’s will breed • Female needs area safe from male • Males more likely to display, females shy • Males breed at 3 years, females much later
Breeding
• Eggs start 3-6 weeks after males start booming • Females pace area 2-3 days before laying • Males chase females - normal • Inexperienced males can kill females – May need to be separated
Incubation • Eggs moved to incubator when found • 11-14 days to recycle • Grumbach incubator – Turned every 2 hours – 37.5°C, 50-60%RH – ~15% weight loss • Moved to hatcher at internal pip : 24 hrs from int pip to hatch on day 23
Hand rearing • Hand reared > tractable adults [males can be aggressive to keepers] • Reproduction not compromised • Increased production • Do not pinion • Angel wing • Sexing – DNA from egg or chick – Or just wait a few mos!
Hand rearing
• Avg hatch weight 77- 116g. Wt not indicator of sex • Prone to dehydration first few days • Chicks can be housed together if <14 days apart in age • Male chicks more vocal, preen more & skyward look more vs. females
Hand rearing • Fed every 2 hours 6AM- 6PM • Lose weight for 2-3 days following hatch • 7-10% daily weight gain • Omnivore diet, insects, no prey until 1 mo • Not cold tolerant • Feather duster, mirror, heat lamps • Exercise very important
Relative proportions of dietary components for kori bustard chicks
Dietary Component Day (d) 0-2 d 3-10 d 11-21 d 22-30
Pellet 20% 25% 33% 33%
Insects (crickets, 10% 10% 7% 7% waxworms)
Egg 0% 5% 5% 5%
Greens 5% 10% 15% 20%
Vegetables 25% 25% 25% 25%
Fruits 40% 25% 15% 10% Domestic Transport • Juveniles shipped ~9 mo or older • Adult males & females in large crates – Male: 0.89m high x 0.91m long x 0.64m wide – Female: smaller • Wooden crates, well padded, ventilated, carpeted, strawed floor
Egg Transport Egg Transport
• Late stage of incubation: day 21
• Portable brooder – Land transport
• Cooler – Air transport – Hand warmers – Clear it with the airlines ahead of time!
Kori bustard Research at NZP • Improved nutrition for captive • Documenting seasonal weight birds changes in breeding males • Development of a hand-rearing • Documentation of a previously protocol undescribed male breeding display • Identification of health concerns and trends for investigation • Documentation of egg turning frequency and incubation • Conducting two in situ field temperature in females projects focusing on the health of kori bustards in the wild, the • Documentation of the effect of results of which will be directly crowd levels on individual applied to improve the health behavior and space usage and husbandry of captive kori • Spearheading a retrospective bustards morbidity and mortality study to • Development of an ethogram gather historical data - the results of which will be used to • 12 year behavior study on adults further refine current • Chick behavior study management techniques
Questions?