How the Purple Fairywrens Survived Extreme Floods: Bird Expert

How the Purple Fairywrens Survived Extreme Floods: Bird Expert
Researcher Niki with a purple-crowned fairywren male in full breeding plumage. (Niki Teunissen/Australian Wildlife Conservancy)
Jessie Zhang
6/28/2023
Updated:
6/29/2023
The resilience of the iconic Australian birds—purple-crowned fairywrens—who were found alive and well four months after extreme flooding despite all their nests being washed away is noteworthy, according to researchers.

The Western Australian floodings at the start of the year brought heavy rain and swelled the nearby Fitzroy River to nearly 15.81 meters (52 feet) high, causing large-scale devastation, including the mass loss of life and habitat for the native wildlife in the area.

But the small, social birds were found mostly safe in their usual habitats of dense vegetation along the riverbeds and creeks.

“Although the fairywrens have taken a bit of a hit from the flood, they are doing well considering,” Monash University PhD student Ian Hoppe said.

A group of 242 purple fairywrens were discovered, a slight decline compared to 256 birds in Nov. 2022, one month before the floods.

The reason that the fairywrens survived is because of their speed and flexibility in adapting to traumatic experiences, said Postdoctoral Research Fellow Niki Teunissen, who has been researching the lives of these elusive birds as part of an 18-year research project.

A purple-crowned fairywren at Mornington Wildlife Sanctuary. (Wayne Lawler/Australian Wildlife Conservancy)
A purple-crowned fairywren at Mornington Wildlife Sanctuary. (Wayne Lawler/Australian Wildlife Conservancy)

“The fairywrens have recovered so well afterwards because of their flexible breeding schedule. Following the failure of a breeding attempt, these birds can re-nest almost immediately!” Teunissen told the Epoch Times.

One in three of the breeding groups in the population had fledglings accompanying the adult birds, despite all nests being washed away in the flood.

While the usual mating season is from December to April, multiple wrens were also found to be breeding one month later in May, with adults feeding young chicks in the nests, incubating eggs, and starting to build new nests.

“Compared to other birds, many species have more fixed breeding schedules, and those would be less flexible in shifting their breeding,” she explained.

Another reason the bird researchers believe the fairywrens survived the floods was the tall trees in their territory, such as figs and paperbarks, which served as a refuge for the wrens to retreat to from rising water levels.

This is why riparian vegetation—plants lining waterways—needs to be protected for the survival of not only the birds but perhaps also small mammals, amphibians, and reptiles living nearby, Teunissen said.

“Our results highlight the importance of intact riparian vegetation, with not only good low- to medium-height dense vegetation for breeding but also tall, emergent trees for retreating into during times of extraordinary floods,” she said.

“We suspect these trees act as a beacon and retreat for many local species but also other species nearby that are mobile enough to reach them. That is, it is essential to protect intact, riparian zones as these tall trees take longer to grow.”

Purple-crowned fairywrens have been found to perform duets with their partners. (Michelle Hall)
Purple-crowned fairywrens have been found to perform duets with their partners. (Michelle Hall)

Faithful Birds

Unlike other fairywrens that have a reputation for promiscuity, the purple-crowned fairywrens are monogamous, taking only one mate and staying close to them for most of their lives.

The birds do not always mate for life, but they can form stable relationships with couples raising their young together and defending their territory together outside the breeding season.

The pair work together with relatives in the group to raise young and defend against predators such as goannas, snakes, and goshawks.

To put this in perspective, 90 percent of superb fairywren nests have at least some young in them that is from a different father.

“That was kind of the rule for fairywrens,” Teunissen said.

“But purple-crowned fairywrens are an exception to the rule. They’re really faithful.”

To put an additional feather in their caps, purple-crowned fairywrens, more than any other fairywren, are known to perform duets with their partner.

A 2009 study by ornithologist Michelle Hall and Prof. Anne Peters showed through a playback experiment that mating pairs of purple-crowned fairywrens combined 50 percent of their songs.