- Another rare AZA/SSP Amur Tiger dies unexpectedly during routine exam

Endangered tiger deaths now at five in 12 months and a "Species Survival Program" down 36% from when it was first started 40 years ago.

Related story: Association of Zoos and Aquariums, Drowning in Failure.

"Putin" had cardiac failure during a normal medical operation, according to the zoo, and despite emergency attempts by veterinarians and zoo workers, he did not survive.

"Today is a tremendously difficult day for everyone at the Minnesota Zoo, and we will be in sorrow for a long time," Minnesota Zoo Director John Frawley said.

The tiger was being examined for a preventative health check, which included the collecting of samples to aid breeding operations. According to the zoo, there are around 103 Amur tigers in AZA-accredited zoos across North America, with less than 500 remaining in the wild.

"This was a regular treatment that is an important component of our tiger care and conservation work," said Dr. Taylor Yaw, Chief of Animal Care, Health, and Conservation at the Minnesota Zoo. "These types of assessments are planned weeks in advance." The team took all essential procedures and tried all in their ability to save the animal. We'll learn more in the coming days and months, and we're grateful for the pathology experts at the University of Minnesota's expertise and assistance as a necropsy is performed."

"Putin" was born in the Czech Republic in 2009 and spent six years in the Denmark Zoo before coming to the Minnesota Zoo in 2015.