Why did the turtle cross the road?
Have you ever seen a turtle in one of Canberra’s urban wetlands and wondered how it got there? Bruno Ferronato explains how citizen scientists are helping to answer this question through the ACT Urban Turtle Project.
Volunteering type: citizen science
Eastern Long-necked Turtle by Raw Shorty
How does Canberra’s urban population of Eastern Long-necked Turtles move about the city? Dr Bruno Ferronato has observed that many of them ‘just use the drains and go with the flow’.
Bruno, Waterwatch Coordinator, and Anke Maria Hoefer, ACT FrogWatch Coordinator, are running a research project on Canberra’s urban turtles. With the help of volunteers, they’re observing how turtle populations differ across connected and disconnected environments in urban areas.
Bruno, Anke Maria, and a group of volunteers trap turtles once a month from September to March, in a range of wetland environments across the ACT. ‘Our sites include four stormwater ponds including the Lyneham and Dickson wetlands in lower Sullivan’s Creek, and four stormwater ponds in lower Ginninderra Creek’.
They have around four volunteers at each site who help with trapping. Bruno explains that the volunteers ‘help trap and record biological measurements. They learn stuff about turtles as they go. We have had a few webinars on turtle biology, so volunteers have a bit more knowledge about the turtles we’re studying.’
In addition to trapping turtles, the project is also looking at nesting behaviour. ‘We train our volunteers how to find nests’, which Bruno explains can be a bit tricky.
This year, the project received an ACT Environment grant to continue doing the nesting projects, on top of funding for the trapping. They’re hoping to continue the project for two years to get a good sense of turtle numbers and nesting in Canberra’s urban environments.
They were drawn to this project because Bruno had only studied turtles in sites that were quite connected, where turtles could migrate relatively easily and move about. Bruno and Anke Maria were curious about how turtles get to and move about in urban wetlands.
‘We were thinking, what happens in urban wetlands? How do they get here? How are the numbers?’
So far, their research has found that turtles in urban environments are about four times less common than in more connected areas. Even so, they’ve found over 29 in Canberra’s disconnected urban environments.
So how do the turtles get to environments like the Lyneham or Dickson wetlands?
‘Some people might find them and put them here, but they also move through the drains. We think that when it rains animals get washed into the drain and end up finding places like this’.
‘This turtle species is quite mobile, and when it rains in spring and summer, they move on land to find new wetlands. We really thought this would be prevented here in urban environments, but now we’re trying to quantify exactly how many are here.’
‘When we do our volunteering, people are so interested.’ Bruno retells how some people find turtles nesting in their back yard and that they’re often mistaken for pets. ‘They might fall into drainage lines and end up a bit lost or in places they’re not supposed to’.
Changes in nesting habits is one interesting finding from this study. Bruno explains that ‘in a normal situation, a turtle will come out of the water, move up the bank and when they find an open flat surface, and that’s where they nest. However, in some sites, after all the rain we’ve had there is a lot of thick invasive grass that prevents the animals from finding a flat surface to nest in’. So, they found many turtles laying their eggs at these barriers of grass, sometimes on 25-degree slopes and sometimes at the base of fences. ‘This is very unusual behaviour that you wouldn’t see in a normal situation’. Because of this, they started looking in different places for turtle nests and found many more nests than they had originally thought. Despite less-than-ideal nesting spots, ‘months later we found the hatchlings and they had survived’. ‘This coming season we might explore this nesting behaviour a little more’.
Bruno has an interesting fact about turtles’ distinct odour. If you’ve ever smelled a stinky turtle, it’s not caused by urine or old pond weed. Turtles have musk glands on the underside of their bodies. If you pick a turtle up around it’s middle, it will secrete a foul-smelling musk. People often mistake this secretion for urine, but it’s thought to be produced specifically to deter predators.
Citizen scientists are critical to the success of the turtle project. In 2020, they found over 41 Eastern long-necked turtles in just one urban stormwater pond! Getting involved is a fantastic way to contribute to new knowledge on Canberra’s turtles and learn new skills in trapping, monitoring, and finding nests.
Get in touch with Bruno here if you’re interested in finding some turtles and learning new skills.