AUSTRALIA: Piss off: dingo pee deters marsupials
Academics at Curtin University of Technology's department of environmental biology in Perth began an investigation into the use of predator urine three years ago to deter kangaroos from ruining the rehabilitation of vegetation on mine sites.
The research revealed that dingo urine could repel wild kangaroos from some areas of new-growth vegetation. Project leader Dr Michael Parsons said at the time that once an appropriate delivery mechanism could be developed, the repellent could be applied in newly-restored areas of mine sites to prevent re-established plants being grazed by kangaroos.
Eight partners assisted the study, including mining companies, the state government's Chemistry Centre, Perth Zoo and a wildlife park. Parsons said numerous attempts had been made to manipulate herbivore behaviour through the use of predator communication signals, but the discovery of the powerful effect of dingo urine had enormously useful applications to deter native animals.
An initial study looked at the effect of American coyote urine but found that what dingos produced had a far greater impact on kangaroos. When tame kangaroos encountered coyote urine, they became interested in the new smell but when presented with dingo urine they were startled and fled.
Parsons said the study offered the first evidence that native predator-based chemical cues in urine affect what area kangaroos chose to feed from, while increasing fear.
Analysis of the dingo urine found it contained a complex array of more than 200 different chemicals. A recipe was prepared with each chemical in the right ratio and sent to the Chemistry Centre to be produced as a gel.
Last week, Parson announced that Tasmania's marsupials had been offered a life-line as a result of the research. Historically, Tasmania's logging industry has used 1080 poison, shooting and more recently cyanide to kill kangaroos and wallabies in areas marked for reforestation but this is unselective and kills all wildlife.
He said dingo urine that had been partially synthesised and turned into pellets by the Chemistry Centre, had repelled wild marsupials when spread in areas of new-growth forest. The pellets therefore provided an alternative to lethal baits and shooting.
Field trials using pellets made from fresh dingo urine demonstrated "a consistent flight response by kangaroos, wallabies and possums due to the assumed presence and fear of predators", Parsons said.
"Also, other trials demonstrated that forest kangaroos were repelled for 31 days from encroaching rose gardens around a domestic residence. A filmed response showed kangaroos approaching cautiously from 4-6 metres away then fleeing the area."
"Overall we spent 212 days in the field testing the urine. The majority of macropods did not breach the urine barrier at any time throughout these tests, the exception being the curious brush-tail possum."
But there appears to be one complicating factor: the urine has to smell as if it has just been produced. A study comparing the effect of fresh dingo urine with aged urine found that fresh urine had a 'time stamp' with a heightened deterrent effect as animals were more wary of a predator they thought was nearby, rather than an animal that might be long-gone.
"We used chemosensory cues, and time-stamp, present in the fresh dingo urine to manipulate the behaviour of the macropods, by taking advantage of the innate and learned fear of natural predators," Parsons said. "There was no effect when aged dingo urine was used."