Auckland Zoo has taken the "heartbreaking decision" to re-home its two female elephants to an overseas zoo.

Burma, a zoo resident since 1990, and Anjalee, who has been at the zoo since 2011 as it tried to build a "sustainable elephant family herd" however challenges beyond the zoo's control the past five years mean they need to move on, Auckland Zoo director Kevin Burley says.

"Over the past five years, changing circumstances beyond our control mean that we are no longer in a position to give them the long-term future they need.

In what it's dubbed as a 'heart-breaking decision', Auckland Zoo has decided to re-home its two female elephants to an overseas zoo.

Burma has been at the zoo since 1990 and Anjalee since 2015 as it tried to build a "sustainable elephant family herd" however challenges beyond the zoo's control the past five years mean they need to move on, Auckland Zoo director Kevin Burley says. (edited)

"Over the past five years, changing circumstances beyond our control mean that we are no longer in a position to give them the long-term future they need.

An additional female elephant was expected to arrive from Sri Lanka's Pinnawala Elephant Orphanage shortly after Anjalee in 2015 but that hadn't progressed, and she remained in Sri Lanka, Burley said.

Adding to that, five artificial insemination attempts, working with the world's leading reproductive experts, were made with Anjalee between 2017 and 2019, however none were successful.

"Now, a number of insurmountable challenges mean that no further AI attempts are currently possible here in New Zealand."

Anjalee was now 14 and for her future health and wellbeing, the zoo wanted to do everything to protect her ability to breed.

"Now aged 14, she needs to get pregnant soon to avoid the long-term reproductive health issues that can face female elephants if they don't breed.

"Having exhausted all current possibilities to breed her here at Auckland Zoo, we will now work to move her to another accredited zoo programme where she can live in a multi-generational family herd.

"There she will be able to mate naturally with a bull elephant and have the best possible chance of eventually having her own elephant calf," Burley said.

However, exactly where she would go was not yet known as the zoo was currently working with its international zoo colleagues to ensure it finds the "best possible home overseas that meets both Anjalee and Burma's respective needs for their long-term wellbeing and future security".