Latest news with #WildResearch
Yahoo
22-07-2025
- Science
- Yahoo
Surprising discovery in remote Aussie creek
It's doubtful many Aussies could find a spotted tree frog in the bush. First of all, there are only around 1,000 adults left in the wild, and then there's the problem that they're no bigger than a matchbox. Amphibian ecologist Dr Matt West had the difficult task of releasing 275 captive-bred frogs into a Victorian wilderness and then trying to find them again to see if any survived, by looking under rocks, on top of plants, and in the ripples of cold streams. 'They were also well camouflaged, so they're very difficult to find,' he told Yahoo News Australia. But despite these challenges, the team was "surprised" to find many more than they initially expected were still alive, despite them facing multiple threats. The spotted tree frog was listed as critically endangered after numbers plummeted due to a series of horrifying events over the last 30 years, including the introduction of deadly chytrid fungus, the spread of introduced fish, and the Black Summer bushfires which wiped out half of its habitat in Victoria. The release of the frogs is designed to help revive populations and boost genetic diversity. The frogs were bred at Melbourne Zoo, and then set free as juveniles into the Kiewa River system, which snakes through Mount Beauty in northeastern Victoria. Their range naturally stretches from northeastern Victoria into NSW. The work is part of the Spotted Tree Frog Project, a collaboration between West's company Wild Research, Zoos Victoria and Duduroa Dhargal Aboriginal Corporation. Why researchers initially struggled to find many frogs There can be a lot of variation in the appearance of spotted tree frogs, depending on their environment. Some are bright green, while others are brown, but all have noticeable bumps on their skin, which is why they're called "spotted" tree frogs. The frogs were released in February, and researchers then had to work fast and track the frogs before winter set in and they became dormant. 'We were going back every month and spending a week out there at a time searching possible areas for the frogs,' West said. 'Initially, we were looking in a tight, little search area where they were released, and we were worried because we weren't finding many of them.' 🐸 Rare frog rediscovered in 'lost world' at edge of cliff 🐸 Tiny creature that almost vanished in the 1990s secretly released ❌ Australian frog declared extinct after decades-long search The team then broadened their search area, and were surprised to find many of the frogs had travelled up to 2km. While this was considered 'unusual' for the species, previous surveys have focused on adult animals, and the frogs they released were juveniles. The difficulties experienced in finding rare frogs When counting other species of frog, it's common for researchers to track them down by listening for their call. But spotted tree frogs can live for up to 18 years, and don't become sexually mature until around five, so they don't start to call for a mate until then. Besides, the search was conducted around a noisy creek, which roars so loudly it's nearly impossible to hear much at all. So instead, the specialist team had to look out for their eye shine and body shape. 'It's very tricky to find them, they've got very small eyes, and a very small eye reflection as a result. Unfortunately, there's a lot of other things that reflect in their environment as well, like little flecks of granite, water droplets, and spiders,' West said. What's the best place to release the frogs? Because the frogs face multiple threats in the wild, only around one per cent have traditionally survived to adulthood. To minimise their chances of death, the frogs were set free in safe havens. Many of the best spots were bushfire-affected, with little vegetation, so the sunlight could reach the creeks. That's because warmer regions, where the air temperature soars above 25 degrees, make it difficult for chytrid fungus to survive. Other places were chosen because they were free of introduced species like trout. Their choices appear to have been successful because, surprisingly, around half of the captive-bred animals were relocated during their search. To date, 600 frogs have been released as part of the Spotted Tree Frog Project. Love Australia's weird and wonderful environment? 🐊🦘😳 Get our new newsletter showcasing the week's best stories.
The Guardian
21-07-2025
- Science
- The Guardian
Hopes high as hundreds of critically endangered frogs survive release into wild in Victoria
Hundreds of captive-bred, critically endangered frogs are managing to survive after being released at a fast-flowing mountain stream near Mount Beauty in Victoria, with some moving a 'considerable distance' from the release point. More than 600 spotted tree frogs have joined dwindling wild populations in the Kiewa River, as part of a Zoos Victoria conservation breeding program to boost numbers and genetic diversity after 50% of the frog's Victorian habitat was severely burnt in the 2019-20 black summer bushfires. This year a team of biologists from Zoos Victoria and Wild Research released 265 one-year-old frogs, following a 2024 cohort of 300 tadpoles and 70 juvenile frogs. So far more than half of the animals released have been found again, according to the Wild Research director, Dr Matt West, who has been part of a team tracking their survival after release. 'Quite a large proportion of those animals are actually surviving, which is exciting and brings us a huge amount of hope that we might be able to recover this population of spotted tree frogs.' Sign up to get climate and environment editor Adam Morton's Clear Air column as a free newsletter It was promising news for a species facing numerous threats, including a disease called the chytrid fungus, predation by introduced fish species like trout, flash flooding and bushfire. Even though the frogs were individually marked (with a skin clip on their toe), finding them again could be challenging, West said. Spotted tree frogs grew to about 6cm long and were well camouflaged with their vivid green spotty skin. 'They are very difficult animals to find because they look very similar to the types of things they like to sit on – granite boulders, ferns and sedges,' he said. The task of finding them was made even more difficult after many of the captive-bred animals had moved 'a considerable distance' – about a kilometre in a year – from the section of stream where they were released, West said. 'It's challenging walking up and down the stream, just for a couple of kilometres. But when you've got to extend that out to 10km, it makes it even more difficult to find a frog.' Sign up to Clear Air Australia Adam Morton brings you incisive analysis about the politics and impact of the climate crisis after newsletter promotion Spotted tree frogs live in mountain streams of the Great Dividing Range between Victoria's central highlands and Mount Kosciuszko in New South Wales. Dr Kirsten Parris, an amphibian ecologist at the University of Melbourne, said spotted tree frogs were 'beautiful' and 'super cute', and one of approximately 80 tree frog species (in the Hylidae family) in Australia. 'They're all classified as tree frogs, but they don't necessarily all climb trees.' Deon Gilbert, a threatened species biologist with the zoo, said the Kiewa River reintroduction site was chosen for its existing, albeit small, wild population and lower trout abundance, meaning fewer predators. The limited canopy in that section of stream also offered more sunlight – providing opportunities for the frogs to sunbathe and warm up on the rocks – an activity thought to be protective against chytrid fungus. The survey required a huge team effort. Traditional owners, recreational fishers and community members joined biologists from Zoos Victoria and Wild Research, walking up and down the stream with headlamps, looking for frog eyes reflecting back and listening out for calls. Gilbert said the team would continue to monitor the health and survival of the released frogs, but it was promising to see them persisting and moving within the landscape. 'Fingers crossed things start looking up for them.'
