The disturbing death and public autopsy of a giraffe at the Copenhagen Zoo in Denmark sparked international backlash last weekend, leading animal advocates to cry foul and the zoo to defend its actions. Then, word broke that a popular drive-through safari park in England euthanized a group of lions to combat problems stemming from unplanned mating and "relatively high levels of inbreeding."
Now, reports of other European zoos euthanizing their river hog piglets, pygmy hippos, tigers, antelopes, bison and zebra to preserve genetic diversity in their populations have surfaced, says TIME.
"As a conservation organization, we realize that there's a crisis in the natural world, and that we have an obligation to protect species in the wild from human actions," says David Williams-Mitchell, communications and membership manager for the European Association of Zoos and Aquaria (EAZA). "One of the ways we do that is through breeding programs. But we have limited space within EAZA to carry out that, and we need to prioritize animals that can contribute to future of the species."