The Royal Botanical Gardens apparently have a very tight budget. They open at 7am, which is way too late for most of the city dwellers who would like to walk or run through the fabulous parklands as part of their daily exercise. Over many years we have been told that the Gardens cannot afford to hire rangers who safe guard the precious plants. Apparently, plants do get stolen!!! (My sub-idea is please stop stealing plants from the Botanic Gardens!) Instead of hiring expensive human labour, the Gardens should consider buying drones to monitor visitors. The drones would be equipped with heat sensor cameras to follow visitors, especially around areas where plants are most likely to be stolen. The drones would also have small pumps with the ability to microinject a smelly and bright colored substance on the offenders. The substance would be non-toxic, but the smell and colour would hang around for a couple of days to make the life of the thief especially uncomfortable. A single individual could control up to 10 drones, at an annual cost of under $100,000 (this includes the salary of the human). I expect the RBG spends more than that on the rangers. I would be happy to start the RBG Drone Crowd Fund to get the idea going.