06/11/2012 at 04:25 PM EDT
It seemed like the fairy-tale marriage, but the love affair has soured for Bibi and Poldi, two giant tortoises at Austria's Reptilienzoo Happ.
The 115-year-olds grew up together and have been living as a pair at the zoo for the past 36 years, according to the Austrian Times
For reasons unknown, the tortoises "seem to have fallen out," says the zoo's Helga Happ. "They just can't stand each other."
Bibi attacked Poldi and took out a piece of his shell, then continued to attack him, prompting the zoo to move Poldi. Giant tortoises are capable of killing each other in attacks.
It seems Bibi was at a point in her life where she just wanted to be alone. "We were told that it's very rare that after so many years animals who are a pair will fall apart, but that's where we are," Helga says.