ABC Ballarat / By Gavin McGrath
Posted Fri 15 Apr 2022
A journey has just begun.
It's a dangerous journey, with the threat of exotic predators, and perilous crossings. If the journey is successful it may take 70 years.
So begins the life of an Australian freshwater turtle.
Eastern long-necked turtles have just hatched along waterways in south-east Australia and you may spot them on the move.
They are one of three freshwater turtle species that can be found in Victoria, New South Wales and South Australia.
All three have feet, but they are all semi-aquatic as well.
Ecologist Donald McKnight up close and personal with a broad-shelled turtle.
(Supplied: Angela Simms)
Turtles or tortoises?
James Van Dyke, senior lecturer in biomedical sciences at La Trobe University, studies the conservation and ecology of turtles.
He says the three species commonly found in south-eastern Australia are technically turtles even if many Australians call them tortoises.
"A lot of the freshwater turtles we have in Australia have feet, but they are webbed feet. They need that to be able to swim through the water," Dr Van Dyke said.
"They got the name 'tortoise' because a lot of them do walk on land on occasion, especially the long-necked turtles you see going overland sometimes.
"Either name is fine. We call them tortoises or turtles here in Australia."
James Van Dyke, senior lecturer in biomedical sciences at La Trobe University, studies the conservation and ecology of turtles.
He says the three species commonly found in south-eastern Australia are technically turtles even if many Australians call them tortoises.
"A lot of the freshwater turtles we have in Australia have feet, but they are webbed feet. They need that to be able to swim through the water," Dr Van Dyke said.
"They got the name 'tortoise' because a lot of them do walk on land on occasion, especially the long-necked turtles you see going overland sometimes.
"Either name is fine. We call them tortoises or turtles here in Australia."
A Murray short-necked turtle (Emydura macquarii).
(Supplied: Angela Simms)
Foxes and other hazards
The eastern long-necked turtle (Chelodina longicollis) breeds from November to January and hatches about three months later.
Murray short-necked turtles (Emydura macquarii) nest about the same time but tend to hatch a little earlier, while the broad-shelled turtles (Chelodina expansa) nest in autumn and most often hatch in spring or summer.
Throughout their incubation, there is the threat of foxes. And that's just the beginning of the hazards they face over a life that can — with more than a little luck — span more than five decades.
"Foxes eat the eggs and nests. In some nesting areas you will just see a whole bunch of holes with shattered eggshells all over the place," Dr Van Dyke said.
"The other thing is adults get hit and killed on roads sometimes. They can live a long time so if you get just one killed when it's hit by a car that's a very important animal gone.
An eastern long-necked turtle (Chelodina longicollis)
.(Supplied: Donald McKnight)
"Finally, there is the changes in the river flows, which can impact populations as well.
"They're not doing too well. Around the world they are among the most endangered groups of animals.
"Here in Australia they are in decline. Most of them aren't in terrible shape yet but they are definitely becoming rarer."
"Finally, there is the changes in the river flows, which can impact populations as well.
"They're not doing too well. Around the world they are among the most endangered groups of animals.
"Here in Australia they are in decline. Most of them aren't in terrible shape yet but they are definitely becoming rarer."
Carrion-eaters
Turtles play an important role in keeping waterways clean, eating carrion such as dead fish and animals.
They are able to survive well in poor-quality water so a waterway that should have turtles but doesn't is a sign things have gone seriously wrong.
A broad-shelled turtle (Chelodina expansa)
(Supplied: Donald McKnight)
The wetter-than-average weather in south-eastern Australia over the past couple of years has given researchers some cause for optimism.
That has been borne out in population surveys by volunteers.
"We almost never catch juvenile or hatchling turtles when we do our population surveys," Dr Van Dyke said.
"This year we've actually got some. We've got four or five. It doesn't sound like much but it's a lot more than we usually see."
Turtle-spotting
There is a citizen-science project underway called One Million Turtles. Researchers are encouraging anyone with an interest in conservation to help count turtles using the TurtleSAT mobile phone app.
"Across all of Australia there are maybe 10-15 people working on turtles professionally, so we need all the help we can get," Dr Van Dyke said.
"Everyone out there spotting turtles can help tell us learn where they are common, and where they are not so common.
The wetter-than-average weather in south-eastern Australia over the past couple of years has given researchers some cause for optimism.
That has been borne out in population surveys by volunteers.
"We almost never catch juvenile or hatchling turtles when we do our population surveys," Dr Van Dyke said.
"This year we've actually got some. We've got four or five. It doesn't sound like much but it's a lot more than we usually see."
Turtle-spotting
There is a citizen-science project underway called One Million Turtles. Researchers are encouraging anyone with an interest in conservation to help count turtles using the TurtleSAT mobile phone app.
"Across all of Australia there are maybe 10-15 people working on turtles professionally, so we need all the help we can get," Dr Van Dyke said.
"Everyone out there spotting turtles can help tell us learn where they are common, and where they are not so common.
James Van Dyke says people who spot turtles can help experts.
(Supplied: James Van Dyke)
"If they tell us they can't find turtles where they should be, that also helps us.
"We're also about to start a project on the website trying to find the impact of foxes.
"People can participate in a nest predation experience. We will be providing instruction and training on protecting nests and helping turtles cross roads safely."
Good memory not always a good thing
"If they tell us they can't find turtles where they should be, that also helps us.
"We're also about to start a project on the website trying to find the impact of foxes.
"People can participate in a nest predation experience. We will be providing instruction and training on protecting nests and helping turtles cross roads safely."
Good memory not always a good thing
As for rescuing turtles which appear to be heading away from the safety of a waterway, it can be frustrating, especially if they are on their way to an industrial or building site that may have once been close to a waterway.
"It's tricky, especially with eastern long-necks," Dr Van Dyke said.
"Those turtles can be pretty old, especially the big ones which can be 50 years old.
"It may remember there was a wetland where that industrial park is now.
"They wander over land long distances, up to 15 kilometres sometimes. If you try to move them in a different direction, they are stubborn animals. They'll keep wanting to go where they want to go.
"Sometimes you just have to let them do that. If you see them crossing the road, it's best to point them in the direction they were headed and move them to the other side."
Turtle-spotter's guide
Eastern long-necked turtle (Chelodina longicollis)
This is the one you will most likely see crossing roads. They are carnivorous and will take any prey smaller than themselves. Adults weigh about 1 kilogram, with a shell length of about 200-250mm. Females tend to be bigger but the sexes are hard to tell apart. They have a black and tan belly and they also stink a little. Baby eastern long-necked turtles have bright orange markings on their underside.
Murray short-necked turtle (Emydura macquarii)
You may see them basking on a sunny day. They weigh 2-3kg with a shell length of up to 300mm. Short-necked turtles tend to eat a lot of green algae but will also eat anything dead. They are greenish in colour with lighter markings on their head and neck, and have a short neck and chunky head compared with others.
Broad-shelled turtle (Chelodina expansa)
The largest freshwater turtle in Australia. Can weigh up to 6 or 7kg, with a shell length about 450mm. Their necks can be up to a metre long when stretched out. Another carnivorous turtle, they will eat anything they can catch, including fish and yabbies. Broadshell turtles have distinctly flat heads.
Source: 1millionturtles.com
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