It's a hypothetical, but a couple cameras and a sign letting people know the area is under surveillance will probably do.

According to the article:

> The vandals forced their way past barbed wire and dug under a steel gate

so I doubt cameras and a sign sign would've deterred then.

In fairness, that same article suggests cameras would have helped.

> “The failure to build an effective gate, or to make use of modern security services, such as wildlife monitoring cameras that operate 24/7, has in many ways allowed this vandalism to occur,”