Police are investigating a series of mysterious deaths by apparent poisoning at the Sao Paulo Zoo, where 10 animals died in a two-week period.
An elephant, three chimpanzees, three tapirs, and three camels were found dead between Jan. 24 and Feb. 6 at the zoo in Brazil’s largest city. A tapir is an endangered, hoofed animal that is a distant relative of the horse and rhinoceros.
“We can’t explain what’s happening,” said biologist Fatima Roberti, a spokeswoman for the zoo. “We are letting the police sift through the clues.”
At first, police suspected a possible serial animal killer, spreading poison in cages at the zoo, one of the world’s largest. Now authorities are focusing on a more mundane theory: rat poison.
Analysts found traces of three different rat poisons in the cages of the dead animals and are conducting tests to determine if they are responsible for the deaths of the animals, said Antonio Carlos Silveira of the Sao Paulo Civil Police Laboratory.
Results are expected within 10 days, Silveira said.
In preliminary autopsies, some animals showed traces of a poison called sodium fluoroacetate, which is used in powerful rat poisons that are banned in Brazil, Roberti said. If that finding is confirmed it raises the question of who put the substances in the animal enclosures.
In the meantime, staff are keeping a 24-hour watch over the zoo’s 3,200 specimens in case there is someone deliberately targeting the animals.