The 2000s were a wild time for the Dallas Zoo — in the worst way possible. The zoo, owned by the city of Dallas, drew global attention when a 350-pound gorilla escaped and mauled three patrons, including a toddler. Just a few years later, another controversy bubbled up over the proposed relocation of Jenny the elephant and criticisms about the size of her enclosure.

The Dallas Zoo needed a success story, and it got one in 2009 when the City Council turned management over to a nonprofit. What followed was a stunning redemption arc. The zoo broke attendance records, welcomed lots of baby animals and debuted exhibits that attracted donors and the right kind of headlines.

This history makes the recent incidents at the Dallas Zoo that much more disturbing and disheartening. Over the course of three weeks in January, one clouded leopard went temporarily missing, the habitat of langur monkeys was cut open, a vulture was found dead with a wound and two emperor tamarin monkeys were taken from their enclosure.

We are all relieved the monkeys were recovered Tuesday, but Dallas must remain on high alert. The troubles at the zoo must stop.

Gregg Hudson, president and CEO of the Dallas Zoo, told us the tamarin monkeys disappeared even after additional cameras and security measures were put in place following the other incidents.

Twitter users are quipping about the fodder for a Netflix true-crime documentary, but this is no laughing matter. There cannot be another incident. Lives are at risk — those of the animals and those of the zoo staff and patrons. Also at stake is the reputation of the Dallas Zoo, which worked so hard to clean up its act.

The Dallas Zoo runs on a budget of about $30 million annually, and nearly half of that is a stipend from the city. According to nonprofit records, Dallas Zoo Management Inc. spends more than $650,000 on private security. Hudson said that doesn’t include capital investments in fences, cameras and other equipment.

“Frankly, we’re looking to spend a lot more than that now,” he added. “To me, it’s not a question about resources, and I know my board feels the same way. We’ve got to do whatever it takes to make sure the animals, staff and patrons are safe and that they feel safe.”

That’s the right attitude.

There’s no question the zoo’s security has improved since privatization. Before that, its security force came down to a Dallas police officer and two nighttime guards, Hudson said. Yet even the latest deployment of manpower and technology — including surveillance towers from Dallas police — have not been enough to stop the attacks. The evidence suggests the criminal or criminals acted at night, Hudson said.

Still, the cameras may end up helping with the investigation.

Now Hudson’s team is bringing in consultants and considering additional measures. Meanwhile, people around the city are volunteering to stake out the zoo at night, Hudson said.

Best to leave security to the professionals. But we are rooting for police and the zoo to solve the mystery and put an end to this drama.

The Dallas Zoo is still in far better shape than it was under the city’s direction. But neither the zoo nor those who love it can tolerate any more loss.

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