Diversify to survive
“Inbreeding is a big problem in all small threatened parrots” JUSTIN EASTWOOD DEAKIN UNIVERSITY
GENETICALLY diverse parrots are less likely to contract a common deadly disease, a Deakin University study has discovered.
The eight-year study, published in Scientific Reports journal this week, explored Australian parrots’ chances of contracting beak and feather disease compared with their genetic diversity.
Lead author Justin Eastwood completed the research as part of his PhD studies, focusing on rosellas because their large variety of colours made it easier to look at genetic diversity.
“The virus disrupts the production of keratin, the building blocks of a bird’s feathers and bill. So it can be pretty nasty for the birds, and even be fatal,” Dr Eastwood said.
“If birds get infected, the main symptom is that they develop feather deformities, and this can progress to the point where they are completely bald. Some species, like the cockatoo, can also get a beak deformity.
“In this study we found that having a higher level of genetic diversity decreased the chance of becoming infected. But, once infected, it was genetically common individuals in the population that had higher levels of the virus. Those with a more unique genetic make-up weathered the virus better.”
The study’s findings meant threatened Australian parrot populations, such as the endangered orange-bellied parrot were likely to be more susceptible to disease.
Study co-author Mathew Berg said low genetic diversity was mainly linked to inbreeding.
“Inbreeding is a big problem in all small threatened parrots. With orange-bellied parrots there are a tiny number of breeding pairs left in the wild and those pairs are already closely related with poor genetic diversity themselves,” Dr Berg said.
“This is why a lot of conservation management is worried about the fragmentation of habitat and improving the connection of small populations that can often become cut off from others of the same species.”