1) The study collared over 100 dogs across six remote Australian communities to track their movements using GPS and quantify their roaming behavior. 2) The results showed that most dogs had small core home ranges of 0.2-0.4 hectares centered around the owner's house, but some individuals roamed much further with home ranges up to 104 hectares. 3) Younger dogs and seasons were found to influence roaming behavior, while factors like breed, genetics and use as hunting dogs did not have a significant effect. Understanding dog movement patterns is important for modeling disease transmission like rabies between dogs and humans.

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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