Researchers have been shocked but gladdened after seeing purple-crowned fairy wrens at the Australian Wildlife Conservancy's sanctuary in the Kimberley getting frisky for the second year in a row.
According to researchers, the wrens at the Mornington Wildlife Sanctuary on Bunuba and Kija country do not usually engage in romance during the dry season, May to November.
Dr Niki Teunissen is a research associate running on-the-ground studies for a long-term project with Monash University.
"Most of their breeding is usually during the wet season from December to April. But the last few years they've surprised us and there's been a lot of breeding during the dry as well."
The purple-crowned fairy wren is a small social bird found in dense riverside vegetation in northern Australia.
It is hard for the untrained eye to distinguish between male and female wrens, as both have brown backs and wings, and a paler buff belly.
But during the mating season, males distinguish themselves by sporting a vibrant purple crown, while the females have grey heads and chestnut-coloured cheek patches.
Dr Tuenissen said there was some logic to why the birds may have been breeding, due to increased food sources.
"We know that when there's a lot of rain there's a lot of food for them because they eat insects," she said.
But like other researchers, Dr Tuenissen is not certain food is the only reason.
"The year before they bred following a really dry, wet season so we don't really understand that to be honest, we're not entirely sure," she said.
Good conditions for wrens
During the recent survey, Dr Teunissen's team captured the new birds in the population.
There were 56 new birds, most of which were fledglings — birds that hatched since the previous survey in July 2021 — and a few were adult immigrants that had newly joined the population.
The frisky wren activity is a welcome sight for conservationists who took over the sanctuary in 2004 when the purple-crowned fairy wrens were dwindling in numbers due to wildfires, drought, and predatory damage.
As of November, Mornington Wildlife Sanctuary's wren population climbed back up to 204 individuals — an increase from 172 in July 2021 and 143 in November 2020.
"They're really wonderful little birds and it keeps surprising us, which makes it really exciting and really interesting for researchers like us to be studying them."
