Richard Musgrove
Dr Richard Musgrove is a zoologist and science journalist. He writes for Cosmos and Double Helix.
Artificial insemination may allow conservation scientists to get kakapo booming through New Zealand’s forests again.
“Two of the main challenges facing the critically endangered kākāpō are low productivity (only about 40% of eggs hatch) and high levels of genetic inbreeding,” says Dr Andrew Digby, Science Advisor, Kākāpō/Takahē, New Zealand Department of Conservation. That’s were artificial insemination comes in.
The booming call of world’s heaviest parrot, the flightless Kākāpō, used to ring out throughout New Zealand. Now it’s critically endangered, one of the world’s rarest birds — 242 individuals are left, up from 51 in 1995.
“Populations were probably once in the millions”, conservation biologist, Professor Bruce Robertson of Otago University, in Dunedin, told Cosmos.
The range for this nocturnal oddity, found only in Aoteoroa, has been severely reduced since the coming of Europeans, thanks to introductions of rats, stoats and weasels. Kākāpō were once found the length of the country, but are now restricted to Stewart Island, and a few smaller off-shore predator-free islands, to which it has been translocated for its own protection.
Kākāpō are also the worlds only lek-building parrot. Each male clears a chosen area and builds a ‘track and bowl system’ — a shallow bowl is dug with tracks leading to it. The male then uses this area, called a ‘lek’, after the Swedish word meaning ‘play’, to attract and impress females. He puffs up his chest and makes a deep booming noise, the bowl a resonating chamber. The lek will be up on the sides of a valley, says Robertson, which means the sounds carries for kilometres, every night for the three to four months of the breeding season.
“When Europeans arrived in New Zealand, they were still reasonably common, stoats hadn’t been introduced. There were kiore [Polynesian rats], but then the other rats and other things arrived after the fact.. Apparently, they were reasonably common to the point where you couldn’t sleep at night, with the kākāpō, booming and carrying on,” says Robertson.
Conservation has now taken a major step forward with the inclusion of a new massage-based artificial insemination technique in the breeding program.
The method involves semen collection through squeezing, abdominal massage and electrical stimulation. German conservation biologists, Dr Domonik Fischer and colleagues of Wuppertal Zoo and the University of Giessen, who have been using the technique on parrots, were invited to try it on kākāpō by New Zealand’s Department of Conservation (DOC).
The results are published in PLOS One. It was successful, says coauthor, Robertson.
Four chicks were produced from three females in that year, with two of the males involved including one which had previously not re produced, and one with rare and valuable “Fiordland” genes.
Fiordland genes are critically important as they originate in the last wild populations on the South Island.
“All kākāpō breeding happens in the wild. It’s not like you can put them in a cage together. They will actually kill each other if you put them together outside the breeding season,” says Robertson.
“And so, you can take sperm from a male, and you know the female’s about to breed or lay an egg, you can artificially inseminate females, and that way you can choose, or at least help them choose, who’s going to mate with whom.”
“So you can start doing pedigree management of your population and trying to get those rare alleles. Lek mating means some kākāpō males will never get the opportunity to breed. They still have good genetic variation that you want to keep in the population.”
“Artificial insemination is one way of doing this” says Robertson. The technique was also successful in 2022 and will be used again in 2026.
Saving the kākāpō
