Auckland Zoo says Jaka, its 18-year-old tiger, has been put down after an inoperable tumour was found.
Jaka was born at Wellington Zoo in 2000 and arrived at Auckland in 2013 to join sister Molek and her son, nine-year-old Berani.
Jaka had been unwell during the past few weeks and an ultrasound of his abdomen revealed he had a large inoperable tumour in his intestine that had spread throughout his body.
"There is no treatment for this, so euthanising Jaka was absolutely the kindest and only right thing to do," senior vet manager James Chatterton said.
Jaka had a reputation for being very relaxed and curious tiger with a strong "singing voice" and was known as the Christmas tiger because of a love of spices such as nutmeg and cloves.
