The state-of-the-art genomic sequencing methods developed for the critically endangered kākāpō, and detailed in a just-published study, have led to major insights now aiding its recovery. Photo / Peter Meecham
The state-of-the-art genomic sequencing methods developed for the critically endangered kākāpō, and detailed in a just-published study, have led to major insights now aiding its recovery. Photo / Peter Meecham
Scientists have genetically mapped most of New Zealand’s remaining kākāpō to create the richest known dataset of its kind in the world – and a blueprint to help save other threatened species.
The state-of-the-art genomic sequencing methods developed for the critically endangered flightless parrot, detailed in a just-published study, have led to major insights now aiding its recovery.
With just around 250 of the bulky birds alive today, conservationists have long worried whether there’s enough genetic resilience left in the population to secure the species’ long-term survival.
“By understanding the remaining genetic diversity, we can measure it in successive generations and see if we are losing any valuable diversity,” Otago University researcher Dr Joseph Guhlin told the Herald.
“Secondly, the remaining genetic variation can affect traits of individuals; thus, with genomic data, we can predict what those traits will be, allowing better health monitoring and earlier intervention for health traits.
“Because there is such a small number of kākāpō, we can sequence each individual, increasing their chances of long-term success.”
After scientists sequenced the first kākāpō genome in 2015, Kākāpō Recovery and the Genetic Rescue Foundation launched the Kākāpō125+ project to map the genomes of all other surviving birds.
It proved the first time that the entire population of one animal had all been sequenced, and has since begun delivering a wealth of new information about crucial threats.
Last year, research led by Guhlin, and funded through Otago University-based Genomics Aotearoa, pushed even further to create an even more detailed dataset, covering most of the population.
With just around 250 of the bulky birds alive today, conservationists have long worried whether there’s enough genetic resilience left in the kakapo population to secure the species’ long-term survival.
In linking genomic data with observable traits among the birds, the team uncovered a trove of new information about genetic variations affecting their growth, fertility, embryo survival and clutch size.
An analysis of egg shape led to a new baseline test for heritability, while other fresh insights about their early growth rate could now help vets intervene earlier when chicks are sick.
Guhlin’s team also succeeded in generating new “breeding values” to predict their observable traits.
Encouragingly, this work highlighted kākāpō had been managed actively enough over the past 45 years to maintain diversity among their population – and hence, their evolutionary potential.
For scientists working on other endangered species, the research also yielded a “pipeline” of new methods to integrate into their own studies.
“Genomic data has many uncertainties, and small populations add another layer of that,” Guhlin said.
“The team and I have done the highest-quality work we can. This includes many simulations, cutting-edge techniques, and advanced statistical models to capture the best information we can and measure our confidence.
“Our code and methodologies have been made publicly available, and we hope this serves as a blueprint for genomic studies of other conservation species.”
The Department of Conservation (DoC)’s science adviser for Kākāpō Recovery, Dr Andrew Digby, believed the new genetic tools would make an immense difference.
“Kākāpō suffer from disease and low reproductive output, so by understanding the genetic reasons for these problems, we can now help mitigate them,” Digby said.
“It gives us the ability to predict things like kākāpō chick growth and susceptibility to disease, which changes our on-the-ground management practices and will help improve survival rates.”
The research, published in the journal Nature Ecology and Evolution, comes as DoC and Ngai Tahu just moved several birds to Waikato’s Sanctuary Mountain Maungatautari – marking the first time in nearly four decades that kākāpō are living on the mainland.
The species otherwise only live on five offshore islands: Anchor Island/Pukenui and Chalky island/Te Kakahu o Tamatea in Fiordland, Whenua Hou/Codfish Island and Pearl Island near Rakiura Stewart Island, and Hauturu-o-Toi/Little Barrier Island.
Since 2016, the population doubled to reach a high of 252 birds in 2022, putting their island homes almost at capacity.
