WELLINGTON, May 17 (Xinhua) -- In a major step forward for the recovery of New Zealand's critically endangered kakapo, scientists have successfully used artificial insemination (AI) to improve fertility and preserve rare genetics in the species.

According to a study conducted by New Zealand's Department of Conservation, the University of Otago, and Germany's Justus Liebig University Giessen, AI offers a powerful conservation tool to help save one of the world's rarest parrots, by enhancing reproductive success and preserving essential genetic diversity.

Only 142 kakapo, the rare flightless New Zealand parrot, were alive in 2019, up from just 51 in 1995, but the population continues to face challenges due to low fertility and high embryo mortality, said the study released on Friday.

Kakapo breed infrequently, and their mating system means a few males father most of the offspring, leaving some genetically valuable birds without any descendants, said the study published in PLOS One, a peer-reviewed open-access scientific journal.

"Two of the main challenges facing the critically endangered kakapo are low productivity (only about 40 percent of eggs hatch) and high levels of genetic inbreeding," said Andrew Digby, science advisor for kakapo/takahe at New Zealand's Department of Conservation.

"Artificial insemination is an important tool to tackle these issues, since it helps improve fertility and enables preservation of important genetic diversity from individuals that don't mate naturally," said Digby, also co-author of this research.

First achieved in 2009, AI in kakapo has been notoriously difficult, with mixed success until recently. In 2019, a collaboration between New Zealand's Kakapo Recovery Team and German parrot reproduction specialists led to significant breakthroughs, including the use of new techniques for semen collection, such as abdominal massage and electric stimulation.

The study details how semen was successfully collected from 20 males in 93.5 percent of 46 attempts. Scientists then analyzed sperm quality and used the samples to inseminate 12 females.

The results were promising: fertility in second clutches rose from 29.4 percent without AI to 70 percent with it. Four chicks were confirmed to be born from AI, including offspring from two males who had never reproduced, one carrying rare Fiordland genes, according to the study.

"This work has provided methods to enable artificial insemination to be used to benefit kakapo conservation into the future," Digby said, adding that following on from further successful attempts in 2022, the Kakapo Recovery Team will be again using artificial insemination in an upcoming breeding season in 2026.

Despite being moved to predator-free islands, kakapo recovery has been hindered by factors like inbreeding, a limited gene pool, and early embryo death, the study said.

The research showed the new AI techniques not only improve chances of fertilization, but allow conservationists to strategically include underrepresented genes in future generations. ■