Wren’s fruit lures capture the Daintree’s elusive cassowaries on camera

Wren R. McLean’s passion for the Daintree rainforest and its cassowaries led the Southern Cross University Honours student to develop an innovative technique to capture images of the large, shy flightless bird: placing fake fruit lures next to remote camera traps.

Wren’s idea helped her identify 45 individual cassowaries over a 32 kilometre stretch from the Daintree River to the Bloomfield River in Far North Queensland.

Wren will present her Honours research, ‘Aspects of the ecology of the Southern Cassowary ( Casuarius casuarius johnsonii) in the Daintree lowlands, North Queensland’, at the 4th annual Research in Science, Engineering and Environment (RiSE) conference , hosted by the University’s School of Environment, Science and Engineering, this week (October 20 and 21) at the Lismore campus.

“My study is the first to systematically use camera traps for cassowaries and indeed the first use of visual lures with motion sensor camera traps for any species,” said Wren, who is studying a Bachelor of Environmental Science (Honours).

More than 450 visual records were provided by these camera traps which allowed Wren to create profiles of individually identified cassowaries.

“I found 45 different individuals, that’s of all age classes, including the very young chicks. Seeing this number of cassowaries through this area would otherwise be impossible,” she said.

When Wren set out to increase knowledge of the cassowary’s diet and habitat use during the lean fruiting season, little did she expect Cyclone Ita to hit the region the day after she arrived in April 2014. She spent 12 weeks in the field, both alone and with the Kuku Yalanji Jabalbina rangers.

Wren is supervised by Dr Ross Goldingay from the University’s School of Environment, Science and Engineering and Dr David Westcott of CSIRO in Atherton.

“Ross is interested in improving the efficiency of wildlife survey techniques. We came up with the idea of placing fake fruit in front of cameras,” she said.

Wren created the fake fruit by painting hard plastic balls in the typical colours of rainforest fruit: red and blue. She placed the fruit lures in front of 15 cameras, while the remaining 15 monitoring sites had cameras but no lures, a simplistic but effective experiment.

“The lures significantly increased the number of cassowaries detected and reduced the time until the first camera capture. The birds were also twice as likely to stop in front of a camera with lures and in turn spent significantly longer in front of them. This increased the amount of profile shots for identification,” Wren said.

“When compared to the traditional survey technique for the species, which consists of looking for signs of the birds through scats and footprints, this new technique was also shown to be more time and cost effective.”

The study showed there was an average of three birds per site which was two adults of each gender plus a sub adult which was yet to leave the area.

Habitat loss and fragmentation, vehicle strike and dog attacks all threaten the cassowary, which is listed as endangered.

Wren’s work has opened up new opportunities for her to continue cassowary research in Far North Queensland.

“I’ve been invited to be part of the cassowary recovery team. I’ve also been invited to submit a research proposal with a traditional owner group in Cape York to do a survey in the McIlwraith Range of the Kulla National Park. There is very little known about the Cape York cassowary population. That’s exciting,” she said.

More than 30 postgraduate students, comprising a mix of Honours and PhD candidates, will showcase their research at the RiSE conference. Participants will represent the School of Environment, Science and Engineering, Southern Cross GeoScience and Southern Cross Plant Science.

Marine Ecology Research Centre PhD candidate Bijayalakshmi Nongmaithem recently represented SCU at the national final for the 3 Minute Thesis (3MT) competition. Her research thesis, ‘Can whelks contribute to food security and human health?’, aims to assess the potential for developing a whelk aquaculture industry in Australia and develop value-adding avenues for gastropod resources in Australia and India.

Bijaya’s RiSE conference presentation, ‘Biologically active volatile compounds consistent with ancient therapeutic uses of Muricidae mollusc operculum’, will discuss the biologically active compounds in Muricidae molluscs which substantiate traditional therapeutic uses of these whelks.

Photo: Adult cassowary attracted to blue and red fake fruit lures at Jindalba in the Daintree (credit: Wren R. McLean).