The boys presented their science master Graham Medlin with a handful of tiny bones.

“They wanted to know what they were,” Graham said. “So, I came into the museum to identify them.”

Little did Graham realise at the time, but that simple inquiry started a five decades-long association with the South Australian Museum and an incredible 35 years as a volunteer.

The Museum is telling Graham’s story as it celebrates National Volunteer Week (19-25 May).

The museum has 81 volunteers, including the 84-year-old Graham, who now heads the Subfossil Laboratory in the Museum’s world-renowned Science Centre.

Those bones, discovered by the students in a cave, were found in a regurgitated pellet from a barn owl, which are common around Australia.

The owls commonly roost in caves and their pellets, which can build up over decades and even centuries, contain the undigestible parts of their prey, such as bones, fur, feathers and claws.

The barn owls most often eat rodents but their diet can vary depending on the season to include reptiles, frogs, birds, small marsupials and insects.

Graham, who describes himself as a citizen scientist, said the pellets allow his team to track seasonal variations, droughts, plagues and even the arrival of European settlers.

All from piles of owl puke.

He initially began his research with the Museum in 1988-89 thanks to a Commonwealth grant obtained by the curator of Mammals, Catherine Kemper, collecting and identifying 10,500 individual animals found in the pellets. Those finds formed the basis of the collection in the Subfossil Lab at the museum. 

“It was really exciting stuff,” Graham said.

In 1976, Graham discovered a new species of rodent in one of the pellets -the broad-cheeked hopping mouse Notomys robustus, named for its robust cheek arch.

“That’s when it really all started for me,” Graham said. “It was eventually properly described in 2008 but we’ve never caught a live animal.”

Graham was appointed an honorary research associate in 1991, and started volunteering at the museum on Friday afternoons.

He retired Mawson High School after 27 years in 1995 and nowadays comes into the museum two days a week, along with the three other volunteers in his team.

So how many owl pellets would he have sifted through?

“Oh, it would be thousands,” he said. “It’s been an interesting exercise.

“But its all been done by volunteers and everything we have in the lab is second hand, including our old wooden sample draws.” 

Graham was awarded the Unsung Hero of South Australian Science in 2020.