Demand Contraceptives in European Zoos

Surplus animals are the unwanted animals that zoos no longer have space/use for. To create more space for animals that are better attractions, zoos either kill or sell these animals. U.S. zoos favor contraception to limit the amount of surplus animals, while at European zoos, killing surplus animals is standard practice.
Over 600 million people visit zoos per year. More than half of these visitors are families, but with a large portion of just adults. Visiting zoos has shown that it lowers blood pressure and allows for exterior gazing. But would these people find these zoos serene if they were to witness unwanted animals killed before their own eyes?
Sign this petition to make European Zoos practice the use of contraceptives to reduce the number of surplus animals!