Police in Lincolnshire say they are still catching hare coursers on a daily basis.
There have been 550 prosecutions since September 2012, and 1200 reported cases over the last year.
Officers launched their special crackdown 'Operation Galileo' last September and say they are bringing more to justice.
One recent incident resulted in around £30,000 worth of betting on dogs for the offenders.
The illegal sport, which involves dogs like lurchers chasing hares to kill them, can mean big money for those behind it.
But for the farmers it is a blight on their land, and one with huge financial implications as they have to devote a lot of time to finding and fending off the coursers.
Police face a common problem - the coursers will say they have been given permission to be on the land to catch rabbits, and witnesses are often reluctant to give evidence.
Sgt Dave Robinson, from Lincolnshire Police, said:
– Sgt Dave Robinson, Lincolnshire Police
"There can be anything from two people to sixteen. They can do it in large groups or small groups. Obviously if you get sixteen people on farmers land then you can understand why they're upset about people being on their land."
Tim Farmer, from Lincolnshire Police, added:
"They bet on whose dog is the best basically. We've caught one chap earlier on in the season who said he made thirty thousand from three months work last year, so quite a lot of money."
Mark Leggott farms on the Fens close to Boston, and says he has lost count of the number of times he has been targeted.