Maryland's Jane Evans has been credited with making the 500,000th verified frog recording for the Australian Museum's national FrogID project.
Mrs Evans reached the milestone at her Maryland home, which is a hotspot for frogs as it's near Shortland wetlands.
Citizen scientists like Mrs Evans have helped double the number of scientific frog records available in Australia.
Scientists consider this to be crucial for frog conservation.
"Recently we'd noticed frogs with a high-pitched screaming sound. It can be deafening at night, they're so loud," Mrs Evans said.
"I stood outside one night and recorded the sounds."
The project team identified it as a new species, named the screaming tree frog. It was one of two new species found in eastern Australia, the other being the slender bleating tree frog.
They were once thought to be one species - the bleating tree frog.
The finds were revealed last month, after citizens were urged to record frogs daily on the free FrogID app during FrogID week.
Dr Jodi Rowley, FrogID lead scientist, said more than 20,000 recordings had been submitted during this year's campaign.
"So far we're at about 36,000 frogs being identified from 11 species," Dr Rowley said.
"That was more than twice the year before, which is amazing."
The two new frogs boosted the number of native frog species known in Australia to 246, including the recently recognised Gurrumul's toadlet and the Wollumbin pouched frog.
Frog ID Week focuses on a time when frogs are abundant, but Dr Rowley said recordings can be made through the app all year.
"We want recordings every day. We're still getting high rates of submission at the moment - about 1000 across Australia every day."
A team of frog experts, along with students, listen to the calls to help identify them.
"I love sitting down with a cup of tea and listening to some calls," Dr Rowley said.
She said it was a relaxing activity, as long as the frog calls weren't overly difficult to pinpoint.
"It's one of these few instances in life where I concentrate on one thing at a time.
"It's listening to 20 to 60 seconds of what is usually a beautiful chorus of frogs to identify the species."
She sometimes listens to the frog calls late at night if she can't sleep.
"It calms the mind - it's meditation."
Some recordings contain up to a dozen or more species.
"They're not so relaxing. They're a little tricky," she said.
Frogs in the Spa
Jane Evans recalled having a tricky time identifying a frog on her Maryland property many years before the FrogID project was born.
Frogs were attracted to her spa.
"We opened the lid and there were all these frogs in there," she said.
"They weren't green, they were pale brown and grey."
She feared chlorine had bleached the frogs, or some kind of mutation had occurred.
"I felt so bad," she said.
When a tradesman came to fix the spa, he identified them as Peron's tree frogs.
"They come in different colours," she said.
Dying Frogs
Australia has about 240 known species of native frogs, with more than 30 under threat from extinction.
Scientists are particularly concerned about frogs dying in large numbers in winter this year, including in Newcastle.
The museum received about 1600 reports of dead and dying frogs across Australia.
"Some were just one dead frog, others reported dozens. It's not normal at all," Dr Rowley said.
"Frogs have been hit by so many things. They're so sensitive to environmental change. It's pretty awful."
The museum is working with wildlife, biosecurity and environment agencies to understand the deaths.
"We're working to get to the bottom of this," she said.
"Forty species so far were reported dead and dying over winter."
The deaths have now mostly stopped.
Frog scientists hope it doesn't happen again next winter.
The historic decline in frog numbers is largely due to a frog pandemic caused by the amphibian chytrid fungus disease.
But this time, Dr Rowley believes the fungus is "not the whole story".
"Not all the frogs we've been finding dead have the fungus. A lot have it at quite low levels that wouldn't be responsible for the deaths.
"Something else is going on. Certainly the fungus is involved and it is killing frogs, but we're very worried there's something else at play.
"That's where the detective work on these dead frogs comes into play."
The museum was able to analyse many dead frogs because citizens stored them in zip-lock bags in the freezer during lockdown, ready for collection.
