Presentation at 3rd GRF One Health Summit 2015 Session Wildlife, Livestock and Pets

1. Quantification of roaming behaviour of free-
ranging domestic dogs to inform zoonosis
transmission
Faculty of Veterinary Science, Veterinary Public Health
Salome Dürr, Courtenay Bombara, Jaime Gongora,
Navneet Dhand, Michael Ward

2. Research questions
› How might rabies spread in northern Australia following an incursion?
› What impact might a rabies outbreak have?
› What is the best control strategy?
- Vaccination
- dog confinement
- population management
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› Development of a rabies
simulation model in domestic
dog populations

3. Study sites – six remote communities
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Galiwin’ku (Elcho Island):
350 dogs,
2100 humans
5 communities in the Northern
Peninsula Area, Cape York:
450 dogs, 2300 humans
Human-dog ratio: 2.7 – 8.8
Dog density: 140-450 dogs/km2

4. 4

5. 5
› Multi-dog households
› Free-roaming; open gates
› Live in close relationship to
community members
› No rabies vaccination

6. The GPS unit
› CatTraQ™
› customer adapted robust cases
› size: 5 x 5 x 2 cm, weight: 56 g
› accuracy (static test): median distance
from fix point 18 meters
› tolerated by the dogs without any
distress
› time between two records set at 1
minute
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7. GPS collar study 2013 – 2014
› 116 dogs collared within six
communities
- 7 – 20% of the estimated dog population per
community
- 3 time points
- collar retrieved after 2-14 days
- convenience sampling
› Data from 105 dogs further analysed
- 44 female (59% sterilized)
- 61 males (38% castrated)
- age 6 months – 12 yrs (median 3 years)
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8. Sample sizes
• 54 dogs
collared
• 48 usable data
Sept 2013
• 36 dogs
collared
• 32 usable data
April 2014 • 46 dogs
collared
• 37 usable data
Sept 2014
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data from 105 dogs
- 25 from 3 time
points
- 26 from 2 time
points
- 54 from 1 time
point
• 26 dogs
collared
• 21 usable
data
Nov 2013
• 24 dogs
collared
• 20 usable
data
April 2014
• 31 dogs
collared
• 25 usable
data
Oct 2014
Northern Peninsula Area
Galiwin’ku

9. Dog treatments, questionnaire, camera, genetics
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10. Two dogs in Seisia and New Mapoon
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Ninja, male, 4 years
Lucky, male, 2 years

11. Observation of hunting trips
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Weapon, male, 1.5 years Suzie, female, 1 year

12. Data analysis – home range and utilization distribution
› Home range:
defined as the area an animal
commonly uses for normal activities,
such as foraging, hunting and breeding.
› Utilization distribution:
integrates relative time frequencies with
which the various areas are used by an
animal within its HR. It therefore
provides information on spatial and
temporal use of the area.
› Comparing three different analysis
methods
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13. BRB – Biased Random Bridge
› Isopleths representing the
probability of finding the dog at any
point of time within the area
› BRB places kernel functions over
each step (“track”) travelled by the
animal between two consecutive
GPS fixes
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14. Results
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› HR and UD shapes are
generally circular around the
dog owner’s house.
› Core HRs (50% isopleth) range
from 0.2 to 0.4 ha
› Extended HRs (95% isopleth)
range from 3.4 to 5.3 ha
› Some individuals roam much
more with a HR size of 40‒104
ha

15. Risk factors for roaming
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Gender effect  only trends Season effect  significant
Age effect  significant
Non-significant factors:
- Genetics of the dogs (dingo relationship)
- Use as hunting dogs
- Breed
- Region and community

16. Aim of the field study: contact rates
› Depend mainly on the
distance between the
dogs’ homes
› Distance kernel
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17. Thanks to many people and animals involved!
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