Tony was the first to die. They found his body early in the morning of Jan. 24, limp and lifeless, his face a mask of pain.
Three days later, another suspicious death surfaced, with similar signs. By week’s end, there were five more.
Soon victims were dying in groups, poisoned by the same odorless, colorless, highly toxic substance. Desperate authorities have tallied at least 62 deaths but acknowledge that they are not close to making an arrest.
Who is killing the animals at the Sao Paulo Zoo?
Since Tony the chimpanzee died, an elephant, five camels, several tapirs, a pair of rare capuchins, an orangutan, some tiny golden lion tamarins and dozens of porcupines have been poisoned in a case that has baffled Brazilian police and horrified zoo officials and visitors.
Law enforcement agencies have mobilized 50 officers -- including nearly a fifth of the city’s special operations unit -- to hunt down the serial killer, while zookeepers scramble to beef up security, change feeding routines, install cameras and find ways to cope with a rampage nobody can make sense of.
“It’s an unthinkable situation,” said Jose Luiz Catao Dias, technical and scientific director at the zoo in South America’s biggest city. “We have emergency protocols for escapes, for fires, for flooding, for walkouts and strikes. But the Sao Paulo Zoo had no protocol for insanity.”
Worse yet for Catao and his staff, signs point to an inside job, or at least assistance from within -- meaning that a killer may be in their midst, somebody with knowledge of the park’s operations and access to its food supply.
Investigators are probing the possibility of a vendetta by a disgruntled worker or former worker, but some employees say they cannot think of anyone who left the zoo under a cloud or who would kill so many defenseless creatures to make a point.
“If it’s for revenge, then take it out on a person, not on the animals,” zoo biologist Juliane dos Santos Soares said. “Cowards!”
She and her colleagues have been dealing with the horror of seeing so many of their charges die painful, premature deaths. Many of the animals’ handlers had worked with them for decades, like Baira the elephant’s keeper, who knew her so well after 30 years together that he could tell she was blinking differently one day. He immediately informed his bosses, but the elephant died less than 24 hours later, leaving her keeper in tears. The man is still too devastated to talk about what happened.
Lab tests have implicated sodium fluoroacetate, a rodenticide so lethal that a few specks dissolved in water can kill a large dog. A drop in the eye of a human being would cause an agonizing death within an hour or two.
The substance is banned for everyday use in Brazil. It can be bought abroad -- Australia uses it to control its wallaby population -- or manufactured by someone with a modest knowledge of chemistry.
Whoever acquired or made the poison must have known its potency and considered its lack of odor or taste ideal for killing animals, such as monkeys, which refuse to eat anything with a bitter smell or taste, Catao said.
Nobody suspected deliberate poisoning at first. When Tony died, about halfway into a normal life span of about 45 years, a necropsy showed pulmonary swelling in the former circus chimp’s chest but no obvious malignant cause.
The same symptoms appeared in a camel that died three days later, but because the two animals were of different species, lived more than half a mile apart, ate different food and had different water sources, no red flag popped up.
But two days later, the zoo lost three Brazilian tapirs within a few hours, including a 3-month-old named Watermelon. Mere coincidence was impossible.
The park’s directors immediately choked off the supply of food, mostly vegetables and grains grown on the zoo’s own farm, fearing it had been accidentally tainted. Bacterial infection was ruled out -- nothing could jump between species like that -- and toxicological tests came back negative for legal pesticides.
Yet the carcasses kept piling up: another chimp, then Baira the elephant.
Nine days after the first death, the poison was identified.
“We knew it was fluoroacetate,” said a weary Catao, taking off his glasses and trying to rub six weeks of exhaustion and worry out of his eyes. “We knew there is no antidote. There’s almost nothing that can be done once it’s ingested.”
The zoo now knew what was killing the animals. But who was doing it? And how?
“Our first [thought] was the public -- some crazy person who came in and threw contaminated food,” Catao said.
With more than half a dozen animals dead by the beginning of February, the police were brought in. Catao and the chief investigator on the case, Clovis Ferreira de Araujo, sat down to piece together the scant clues.
Araujo suggested a serial killer. In a twist worthy of Agatha Christie, he detected a possible alphabetical method to the madness: A for anta, the Portuguese word for tapir; B for Baira the elephant; C for chimpanzee; D for dromedary, or camel; E for elephant.
They remained focused on the likelihood of a deranged outsider. But then the porcupines changed that.
When the spiny creatures started dying Feb. 15, zoo officials had to face the unpleasant fact that an employee was almost certainly involved. The porcupines lived in the park’s breeding sector, where visitors were not allowed.
The porcupines were decimated -- all 43 in the breeding area died. Only the seven that are out on public display survive.
“It’s a disaster,” Catao said.
The rarest animals poisoned so far were a pair of endangered capuchin monkeys, also part of the breeding program. Three of the zoo’s four chimpanzees have died, as well as five of its six camels and one of its two elephants.
The death count, at 62, may rise after lab tests on more than a dozen more carcasses are completed.
Especially hard was the loss of Karen, a female orangutan, one of a pair that came to Sao Paulo from Indonesia 30 years ago. She had recently survived a painful bout with bone cancer and the park had built a new enclosure for her. It was complete with cleverly placed feeding holes and other items to cheer her up, especially because her mate was in bad shape with spinal cord cancer.
Karen was found dead in a sitting position, one hand clutching an iron bar of her enclosure, blood streaming from her nose, her face distorted. The zoo staff wept.
“I had to pry her fingers off the iron bar because she was holding on so tightly,” said zookeeper Aristeu Jose dos Santos. “I was very sad when I saw that. How could anyone do this? It’s incomprehensible.”
The primate area is now heavily patrolled and the chimpanzee pen, with its lone survivor, is walled off from public view. A team of 15 security guards, up from nine before the killings began, provides round-the-clock security. They are backed up by six police officers, who have a substation in the 200-acre park.
Security is especially tight around the zoo’s rarest treasures, such as its seven blue-feathered Spix’s macaws, of which only a few dozen survive, all in captivity.
Animal feeders now distribute food in pairs and must follow new sign-in and checkout procedures. Of the 19 kitchen employees who prepared the 452 animal menus required at the zoo, most have been reassigned to other jobs pending the results of the investigation.
The extra precautions appear to be working: The last animal believed to have been poisoned, an anteater, died Feb. 20.
Araujo, the chief investigator, said his team was working its way through a list of 40 suspects, all of them current or former employees. But a lack of physical evidence has prevented detectives from drawing any firm conclusions.
“This case has become a priority for us,” Araujo said. “It’s a crime of great complexity.”
The Brazilian Congress set up a special commission recently to look into the poisonings as well. Zoo directors in other parts of the country are worried about the possibility of copycat crimes.
Scientific director Catao is eager for the mystery to be cleared up, if only so that other zoos around the world will not balk at donating replacement animals.
The Sao Paulo park, which opened in 1958, has the largest collection of creatures -- about 3,900 from 450 species -- of any zoo in Brazil.
Many of the poisoning victims were showcase animals popular with visitors, another reason Catao doesn’t think the killings were the random work of a psychopath.
But zookeeper Dos Santos has trouble imagining that any of his fellow handlers could be involved. Many of them have worked at the park for years and are distraught over the loss of animals they tended so closely.
“It’s very sad to go back to their pens and see them empty,” Dos Santos said, shaking his head.
“We work eight hours a day and we have one day off a week. They’re our second family.”