THIEVES have stolen sheep worth $100,000 from a remote property, as soaring meat prices make stock theft a lucrative crime.

Eyre Peninsula grazier Bill Nosworthy said yesterday that 540 Merino sheep worth about $200 each were stolen from his 24,000ha property between Port Lincoln and Streaky Bay.

There were 50 reports of stock theft between July 1 and September 30 last year.

Mr Nosworthy said he had reported the loss to police and put posters in hotels offering a reward of up to $5000 for information leading to the recovery of his sheep.

Brevit Sergeant Paul Bruggemann said police were trying to curb livestock thefts and had achieved good results since the inception of Operation Poach in July last year.

Sgt Bruggemann said a number of people of interest were being monitored and more officers were attending sheep sales and stopping vehicles carrying sheep.He is also alerting livestock agents across South Australia to watch out for the missing sheep.

"It's not only the loss of the sheep, but the losses continue for some time because you receive less income in future from the sale of sheep and wool," he said.

Mr Nosworthy said other livestock producers had told him of sheep being stolen with a lot of farmers not even bothering to report losses.

Heavy stock thefts in rural areas were outlined in the latest SA Police journal Blueprint in which Northern Operations Assistant Commissioner Neil Smith said the level of thefts was the highest since 2004.

"The increase is thought to be directly linked to the exceptionally high prices for stock, with thieves predominantly targetting sheep because they are easier to transport than cattle," he said.

Assistant Commissioner Smith estimated the value of stock stolen during the period was about $500,000.

It follows significant reports of large stock thefts in 2010 with the high price of sheep and cattle reviving the old Australian art of duffing and leading to SAPOL forming Operation Poach to help manage the problem.

Then, thefts of 2500 sheep in one incident and 1500 sheep in another in the Flinders Ranges region, raised concerns about the number of professional stock thieves operating in South Australia.

South Australian Farmers Federation president Peter White said there had been a lot more activity from the police since they started Operation Poach with police attending a lot more stock sales.

Mr White said it wasn't surprising to have a large number of sheep being stolen with the high price of stock because the problem is people don't spend 24 hours a day with their livestock and they are isolated in some cases.

Family First MLC Robert Brokenshire said SA Police's celebration of Operation Poach in its Journal was a vindication of Family First's consistent campaigning to former Police Ministers to do something about the problem.

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