A new study from Flinders University has revealed that Australia’s night parrot does not have very good night vision. The research suggests that these nocturnal birds are no more equipped to see in the dark than parrots who are active during the daytime.
This only adds to the mystery of the night parrot, which completely eluded humans for decades. There were no confirmed sightings of the birds from 1912 to 1979, and they were thought to be extinct.
After an unconfirmed sighting in 1979, night parrots were rarely ever seen. It was 2013 before a population was finally discovered in the remote Australian outback.
Conservation efforts were immediately launched to safeguard the species. In the current study, the discovery that night parrots cannot see well in the dark is raising new concerns about the dangers posed by wire fencing across the Australian outback.
“Night parrots must be able to find their way at night – to find food, avoid obstacles while flying, and escape predators,” said study co-lead author Dr. Vera Weisbecker.
“We therefore expect their visual system to show adaptations for seeing in the dark, similar to other nocturnal birds – New Zealand’s Kakapo parrot and owls with enlarged eyes for example. However, we found that this wasn’t the case.”
Dr. Karine Mardon imaged the intact skull of a night parrot, as well as skulls from related parrots, using CT scanning at the University of Queensland Centre for Advanced Imaging. The team produced 3D models of the skull to compare the night parrot’s brain with brains of related parrot species.
“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,” said study co-author Aubrey Keirnan.
“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 new questions about the night parrot’s ability to survive with low numbers in remote outback of Australia, where fencing is important for stock management.
“These results suggest that removal of unused fences should be a priority in areas where night parrots are known to occur,” said study co-author Nick Leseberg. “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.”
“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.”
According to Dr, Andrew Iwaniuk, the use of anatomical observations to infer the night parrot’s behavior was an innovative approach to understand this rare species.
“The species is so elusive that we do not even know how many individuals are left,” said Dr. Andrew Iwaniuk. “To conserve the species, it is critical that we understand its behavioral needs and capabilities, but these are nearly impossible to observe.”
The study is published in the journal Scientific Reports.