New disease threatens parrots
BFDV affects parrots and cockatoos, and
is now threatening a rare New Zealand
Image: iStockphoto

New Zealand’s endangered parrots could be under further threat from a new genotype of a virulent disease that scientists at the University of Canterbury have recently helped identify.

The scientists are calling for urgent action to protect native parrot populations and are calling on conservation authorities to monitor the incidence of infection.

Dr Arvind Varsani, Dr Melanie Massaro and Dr Brigitta Kurenbach (Biological Sciences) have been working with Massey University PhD candidate Luis Ortiz-Catedral, who has been monitoring and documenting the incidence of beak and feather disease virus (BFDV) in the endangered New Zealand parrot, the red-fronted parakeet.

The results of this research were recently published in the journal, Archives of Virology, in a paper titled “A new isolate of beak and feather disease virus from endemic wild red-fronted parakeets in New Zealand”.

The team has been working to identify the genotype of the BFDV infecting the parakeets on Little Barrier Island where an incidence of approximately 25 per cent infection was found by Luis in earlier research he conducted on the island.

The virus causes psittacine beak and feather disease, a common viral disease found worldwide that affects parrots and cockatoos. Birds affected by the disease can lose their feathers, suffer beak deformities and their immune systems weaken, making them susceptible to other infections. There is no cure and it is usually fatal.

In their paper, the team said there was an urgent need to protect endemic parrot populations from infection and recommended that the incidence of BFDV infections in both wild and captive parrots be monitored by conservation authorities, and that breeders and those working with psittaforms be made aware of the consequences of outbreaks of the disease.

“These actions are pivotal for identifying and implementing management programmes aimed at containing the dissemination of BDFV to captive and wild populations of species at risk of extinction,” the researchers said.

Dr Varsani said it was the first time full BFDV genomes from New Zealand had been documented. In the past, researchers in New Zealand had only looked at partial sequences of BFDV isolated from introduced parrots.

“No-one has characterised the virus at full genome level in New Zealand before and when we compared it to isolates from around the world we found the New Zealand isolate was significantly different to other available BDFV genomes. This means the BFDV isolates from red-fronted parakeets represent a new genotype of the virus.”

Dr Varsani said the discovery of a distinct genotype of BFDV raised questions about whether there were other genotypes or recombinants of the virus in New Zealand, and the potential harm it may have on other endangered native parrot species, such as the kakapo, orange-fronted parakeet or the Forbes parakeet.

“Our goal now is to document the diversity of beak and feather disease virus in New Zealand to determine if they are recombinants and assess their virulence. This information will be of great importance to psittacine conservation programmes,” Dr Varsani said.

Luis, who approached Dr Varsani with the project, carried out the fieldwork by collecting blood samples from 54 red-fronted parakeets on Little Barrier Island with help from Department of Conservation staff and volunteers.

Dr Massaro said the discovery provided the first evidence that native parrots, rather than just introduced species, were infected with the virus. However, it was difficult to know how the virus had spread as red-fronted parakeets were mainly found on New Zealand’s offshore islands. It was also difficult to tell whether the virus was a new arrival or had been around for some time.

She said the parakeets may have been infected from introduced psittacine species, escapees from breeding facilities or the virus isolate could have been endemic to New Zealand but remained undetected in wild species. Transferring birds from one island to another as part of New Zealand’s conservation strategy could also be spreading the disease.

“Another issue is researchers who go from island to island — we could potentially be indirect vectors for the disease.”

Dr Kurenbach said it was amazing to see how a team of scientists from different fields — ecologists, molecular biologists and virologists — could be pulled together to address a question in a short period of time.

The team has recently secured funding from the Brian Mason Trust to train Department of Conservation personnel in BFDV screening and to study BFDV in native and introduced parrots in the Canterbury and Westland region.

Editor's Note: Original news release can be found here.