It sounds like a woolly idea, but Australian sheep are to be fitted with gas masks to find out how much they are affecting the climate.
Researchers will fit the masks over the sheep for a short time to obtain a reading from their breath so it can be established how much methane gas they are emitting.
'Operation Gas Mask' will soon swing into action following a report by Australian climate adviser Ross Garnaut who said sheep helped create greenhouse gases and it would be better if farmers turned to kangaroos as a source of meat.
Sheep and cattle have been blamed for emitting the potent greenhouse gas methane from the mouth and the rear and while researchers in the past have even fitted plastic trousers on a handful of sheep to gather gas, it has been agreed that using masks is a better alternative.
Professor James Rowe, of the Sheep Co-operative Research Centre, said that in any case 98 per cent of methane emissions came from a sheep's mouth.
He explained that during the campaign selected sheep among the country's population of 90million animals would be rounded up at research stations and staff would hold a mask in place over their mouths for about a minute to collect their breath.
'It's a mask over the nostril-mouth area as the animal breathes out,' he said. 'That air is then captured into a bladder, not too different from a football bladder. The animal is not in any distress - they don't really object to it.'
In any case, he pointed out, "putting plastic trousers onto sheep is a much more difficult task than holding a mask in place for a minute or so."
It is hoped the research, with the collected gas being analysed in laboratories, will establish which breeds of sheep are genetically predisposed to emit less methane.
Scientists also believe they will be able to learn about the diet of sheep so that changes can be made to their eating habits to lessen methane emissions.
In his recent report, Professor Garnaut said greenhouse gases over Australia would be cut if people ate less beef and lamb and more kangaroo meat, as kangaroos do not belch methane.
He has suggested that while cattle and sheep numbers could be reduced, the kangaroo population could be increased to 240million.
But Professor Rowe says the kangaroo idea probably would not work, asking: 'Have you tried to muster (round up) kangaroos?'
Kangaroo meat is on sale in Australian supermarkets but few households eat it. The meat is usually purchased for pets