At The Quoin, we use motion-activated cameras (also known as camera traps) to learn what animals are present, which helps us to understand the health of each ecosystem and inform our decisions about restoration work and threat species management. The cameras — robust, waterproof, battery-powered — are typically in the field for around a month, taking photos when they detect motion.
Over that month, they might take tens of thousands of images.
Then, we use Wildlife Insights to identify the species in each geotagged and timestamped image, building up an understanding of where each species can be found in time and space.
For this survey, we used 26 cameras distributed throughout The Quoin from mid-December to late-January, as part of a regular annual program. By taking photos at the same time each year, we get longitudinal insights into how our species mix is changing.
We’re committed to improving the environment for our native animals, and a critical part of that is understanding where our species can be found.
To date, our cameras have photographed a dozen native mammal species — including common macropods such as wallabies, kangaroos and pademelons; familiar marsupials such as possums, potoroos and wombats; a surprising number of Tasmanian devils (purinina) (Sarcophilus harrisii); and rarer, more endangered species such as quolls and bandicoots. We also have photos of introduced species such as fallow deer, rabbits and feral cats.
No double-dipping!
It’s not unusual for a mob of kangaroos, a herd of deer or a flock of birds to spend quite some time in front of the camera. To ensure we’re not over-counting each species, we also look at the time between sequences.
A sequence is a set of images of the same species, taken within one minute of each other. Most sequences have three or more images. We call a sequence independent if it’s separated by more than 10 minutes from the previous sequence.
Where do they live?
Animals have varying lifestyles. Some graze on grass, others prefer different kinds of plants, and others eat insects, birds, smaller mammals and reptiles. Some animals can see long distances and evade predators with speed, others need to find places to hide. Therefore, we should expect to see different species distributions in different landscapes.
In order to draw meaning from our photographs, we assign a landscape type to each camera site.
- Grassland: open areas, both natural and as a result of human clearing (four cameras).
- Woodland edge: the interface between the grassland and the forest (13 cameras).
- Open woodland: where the understory allows easy passage and good visibility (five cameras).
- Dense woodland: with a thick understory (five cameras).
We can then analyse sequence counts by landscape count (the first chart in each set). In addition, we can adjust these raw counts by number of cameras we have in each landscape count, getting an adjusted sequence percentage (second chart) which gives us an understanding of the kinds of landscapes each species enjoys.
Let’s look at three of our most common and recognisable species.
- Bennett's wallaby (payathanima) (Macropus rufogriseus)
- Forester kangaroo (tara) (Macropus giganteus)
- Tasmanian devil (purinina) (Sarcophilus harrisii)
Bennett's wallabies are often seen in grasslands and at the woodland edges, but are also at home in the open and dense woodlands.
Whereas Forester kangaroos much prefer grasslands and their woodland edges.
And the Tasmanian devil likes staying deep in the dense woodlands and is hardly seen in open grasslands at all.
When do the animals come out to play?
Just like our cameras, many animals operate around the clock.
Bennett’s wallabies are the most common animal in this dataset, with more than 1,800 independent sequences. They are active throughout the day and night, but are most active in the evening and the morning.
(During summer at The Quoin, the sun rises before 6am and sets after 8, which is reflected in the radial chart.)
Forester kangaroos, however, like the mornings and the afternoons, tending to sleep in the middle of the day and at night.
Tasmanian devils are most active when the moon is high in the sky. Occasionally, they'll be seen in the morning and early afternoon, but by mid-afternoon they're tucked away in a den, coming out as darkness falls.
Find out more about our camera program:
>>> Oh snap, that’s a curious roo
