The Big Apple’s last polar bear — who was born and raised at the Bronx Zoo — has been euthanized due to age-related medical problems, officials said.

Tundra, 26, suffered from chronic kidney disease that worsened despite treatment, zoo officials said Wednesday.

“Many of us grew up with Tundra,” said zoo director Jim Breheny. “Despite his age he remained extremely active and playful until just before his death.”

Breheny called Tundra, who was born in 1991, “an important ambassador for his species” who taught New Yorkers about problems faced by his brethren in the wild.

The average age for a polar bear in captivity is under 21.

Lovers of the elderly bear bemoaned his Saturday death on social media.

“Just heartbreaking!” a Bronx Zoo member tweeted. “RIP you big, beautiful Tundra! Your fans are shedding tears and will greatly miss you!”

A now-closed Change.org petition had called for Tundra’s release and had garnered 29,757 signatures. Activists claimed that Tundra was “languishing alone in confinement.”

Tundra became the city’s sole polar bear when 27-year-old Gus was euthanized at the Central Park Zoo in 2013.

The Bronx Zoo announced it was not planning on acquiring another polar bear or to exhibit the species again in the near future.

Polar bears can live 20 to 30 years, but only a small percentage make it past 15 or 18, according to the nonprofit North American Bear Center. The world’s oldest polar bear, Coldilocks, celebrated her 37th birthday at the Philadelphia Zoo earlier this month.