Study shows that, despite conservation efforts, the survival of orange-bellied parrots has dropped from 51% to 20% in recent decades.
A study led by researchers at The Australian National University shows that, even after decades of efforts, preserving the orange-bellied parrot, one of the rarest birds in the world, is still a challenge.
The study was published in May in the journal Emu: Austral Ornithology.
For many years, preservation initiatives in Tasmania have managed to increase the breeding rates of this animal in the wild.
Even so, 80% of the orange-bellied parrot born in their only breeding ground die during migration and over winter.
“Our results are very worrying,” said Dr. Dejan Stojanovic, lead author of the study. “We found that over time, survival of juvenile parrots has dropped from 51 per cent in 1995 to only 20 per cent in recent years.”
To reach these conclusions, the researchers used data collected over 22 years by the Tasmanian Department of Primary Industries, Parks, Water and Environment.
“Although more orange-bellied parrots are born into the wild as a result of recovery efforts in Tasmania, these benefits are reduced by threats during migration and winter that are unidentified and unaddressed,” said Dr. Shannon Troy, a biologist, co-author of the research and leader of the DPIPWE Orange-bellied Parrot Tasmanian Program.
Scientists suspect that the biggest challenge faced by these parrots is the Bass Strait, which separates Tasmania from the Australian mainland.
With a small population size, orange-bellied parrots suffer during the migration and, in the winter, the remaining survivors have yet to find suitable habitat in Victoria.
“Determining why birds are failing to survive migration and winter is part of the solution to preventing extinction, which may be unavoidable over the long term if these issues cannot be addressed,” Dr. Troy said.
Orange-bellied parrots are critically endangered, this is the last step before extinction. In 2016, for example, only three females were able to return to breeding grounds after migration.
Even though the population size increased in the following years, reaching 13 females in 2019, the total population size of this species is very small.
“Australia has one of the worst extinction rates in the world, and our study shows that correcting decades of population decline of orange-bellied parrots is extremely difficult, and despite our best efforts, may not be successful,” Dr. Stojanovic said. “We hope our study encourages others to think holistically about the way that we deploy conservation efforts for migratory species, so that good work at one time and place isn’t undone when animals migrate away.”