Pretoria, South Africa (CNN) -- Sniffer dogs in South Africa are being trained to help the fight against poachers of endangered species in a new way.
Dogs have long been used to help police find contraband substances, including ivory and rhino horn.
However, there are times when it is not practical to use dogs on the ground, as the tarmac at border posts gets too hot for them during the day, or if there could be a danger to the animal.
Now researchers at the South African company Mechem are adapting their Explosive and Drug Detection System to the fight against poachers.
The technology involves using a vacuum device to suction air from a suspect area. The filter in the vacuum is then given to the dogs to smell, disguised among blank control filters, and the dog's nose does the rest.
Mechem says this technology helps to get round all the problems that sniffer dogs traditionally face by "taking the odor to the dog rather than taking the dog to the odor."
Mechem's Explosive and Drug Detection System was first developed in the 1980s to detect landmines, weapons, ammunition and drugs. It has now been improved and adapted to detect illegal substances taken from protected species.
Dogs trained at Mechem are now helping the police where conventional canine units are struggling.
Inspector T.C.Oosthuizen, of the South African Police Service, said: "When we work at Komatipoort for instance, the tarmac is so hot, it starts melting so you can't get a dog to work from 12 o'clock in the afternoon.
"And the smugglers, they know about it, so then they know you can't bring a dog to the border posts because the dog of course will burn.
"With this machine you take the samples, and give it to the dog in a controlled environment, an air-conditioned facility. It's cool for the dog so the dog can work longer and more."
The stakes are high. Poachers are smuggling rhino horn to the lucrative Asian market where it's thought to have medicinal qualities and can fetch about $7,500 a kilo.
Conservation groups estimate that there are now only 18,000 rhinos in Africa today, down from 65,000 in the late 1970s.
Dr Hannes Slabbert, Mechem's animal behaviorist and a former police officer, said: "We can search hundreds of cars and the dog will detect the odor that he was trained on.
"So if the dog is trained on your protected species, or your narcotics, or your explosive detections, when your dog indicates we will know that you would then search for the specific contraband."
Slabbart said the dog would detect the substance, as long as it had been collected correctly in the vacuum sampler.
Mechem is working with the South African police to research the feasibility of rolling the system out to all their canine units.
Paul Bester, Colonel in the South African Police Service, said: "I'm very excited because it seems that we have a concept there that can work through all our points of entry in South Africa. It can assist all the dog handlers; make their task a little bit easier for them as well."