Auckland Zoo will be closed tomorrow as staff grieve the loss of 40-year-old elephant, Kashin, who died today.

The female elephant, who has been at the zoo for 36 years, was euthanased after losing her battle with chronic health conditions.

"Zoo staff are devastated, grieving the loss of their incredibly spirited and gentle matriarch," zoo chairman Graeme Mulholland said.

"Kashin touched the lives, not just of the zoo family, but thousands of New Zealanders and international visitors who came to know and love her... she will be greatly missed by all."

He said the decision to put the elephant down followed years of chronic arthritis and foot abscesses.

More recently she had developed skin infections over her body that were not healing.

Kashin's death was expected to have an impact on the zoo's remaining elephant - 26-year-old Burma - who would be closely monitored as another elephant was sought.

In March, the Auckland City Council approved a succession plan for the zoo, quelling fears that Kashin and Burma would be the last elephants to live there.

The zoo plans to build a herd of three males and two females between 2011 and 2015.

The zoo will re-open on Wednesday.