April 14, 2014 12:00 PM

Marius’s last meal was rye bread. It isn’t a food that giraffes forage in the wild, but little felt natural about the scene at the Copenhagen Zoo that February morning. As the 2-year-old giraffe leaned forward to eat, he was shot in the head by a staff veterinarian. Marius then became breakfast for a group of lions, as visitors – adults and children – looked on. A month later the same zoo killed two lions and two cubs, leaving animal lovers around the world angered and wondering: Why would a zoo kill five healthy animals?

Despite protests, Danish zoo officials stand by their decision, saying Marius was put down because he could not be bred: His genes are well represented in captive populations, and so a transfer to another zoo would “cause inbreeding.” As for the lions? “We have two female lions that are offspring of the old lion, and we would have risked that the old male mated with them,” says CEO Steffen Straede of the Copenhagen Zoo. “That is why this change of generation is necessary now. Besides, the female had become too old to have more litters.”

Critics are calling it “zoothanasia” or, worse, murder. But according to Gerald Dick, executive director of the World Association of Zoos and Aquariums, for many zoos this is business as usual. Putting down animals “is always the last resort,” says Dick. “It’s all about population management. In America euthanasia occurs less often. It caught so much attention because they were lions and giraffes – charismatic, cuddly animals. If it had been a mouse or rat, this wouldn’t be news.”

And while it may not inspire choruses of “The Circle of Life,” at the Copenhagen Zoo life does go on: The male lion that replaced the four others is now settling in to his new and spacious home.

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