A Queensland Museum specimen of Australia’s most elusive nocturnal bird, the Night Parrot, has played a vital role in a new international study, which has found that this species may not be much better at seeing in the dark than other parrots active during the day.
Queensland Museum Mammals and Birds Collection Manager Heather Janetzki said at the time of the study, the museum held the only specimen of a Night Parrot with an intact skull. This animal, and several other comparative parrot species from the collection were CT scanned by Dr Karine Mardon, at the Centre for Advanced Imaging and the 3D constructions were compared by Aubrey Keirnan, both of the University of Queensland.
The Night Parrot specimen was a chance find in 1990 during a joint expedition by Queensland Museum’s bird expert Wayne Longmore and Australian Museum’s curator Dr Walter Boles. Its mummified body was spotted on the side of the road near Boulia in western Queensland providing tangible evidence that the species was not extinct.
“We are fortunate to have such a rare species in our collection and this reinforces just how important museum collections are in research,” Ms Janetzki said.
Further information on the species has come from a team of scientists, including co-authors Dr Steve Murphy and Nick Leseberg (University of Queensland), monitoring a small population discovered in western Queensland in 2013. Being nocturnal, Night Parrots need to navigate in the dark often flying at high speeds. While necessary to control stock, fencing (particularly barbed wire), can pose a lethal obstacle for birds, as evidenced by several specimens in the museum collection including two other Night Parrots.
This most recent study uses an innovative approach to understand a species behaviour using anatomical observations, in this case, looking at the parrot’s visual system. Led by Dr Vera Weisbecker (Flinders University) and Dr Andrew Iwaniuk, (University of Lethbridge, Canada) it revealed Night Parrots are not as well-adapted to life in the dark compared to other nocturnal species such as the Kakapo of New Zealand and owls with enlarged eyes.
“We found that the Night Parrot has similar eye size to other parrots, with smaller optic nerves. It also has smaller optic lobes, which are visual processing areas in the brain.” Dr Weisbecker said.
“This suggests that the Night Parrot may not be great at seeing in the dark: its vision is likely sensitive, but with poor resolution, so that it might not be good at distinguishing obstacles like wire fences or even predators in dark conditions.”
The findings raise questions about this critically endangered species’ ability to survive in low numbers. Researcher, Nick Leseberg, suggests the removal of unused fences should be a priority in areas where Night Parrots are known to occur.
“However, we probably can’t go entirely without fences – stock needs to be managed with fences, and some forms of predator exclusion could be important for protecting the Night Parrot, Mr Leseberg said.
“We therefore need to be very careful with our fencing strategies, at least by increasing the visibility of wire fences, but alternatives such as low-tension electric fencing could be even better.”