The fox hunting season has begun - the first since a ban on using dogs in England and Wales - as campaigners claim the laws are being flouted.
Thousands of people are expected at 200 hunts across the country to hunt within
the law. Anti-hunt campaigners will also be out in force.
But 40% of hunts have broken the law, the League Against Cruel Sports says.
The Countryside Alliance dismissed the report's "vague language" and said public support for the ban is falling.
There were 157 allegations of illegal hunting against 89 hunts since the ban was introduced in February, said the report.
Information was gathered from hunt monitors, press articles and tip-offs.
The League's findings are based on evidence relating to 132 of the 317 official
hunts in England and Wales.
Chief executive Douglas Batchelor said its evidence and intelligence had been passed to the police and the government.
"The report shows that many hunts appear to have gone far beyond what the law now allows in their desire to keep on hunting," he said.
Numerous loop-holes in the law exist - hounds can still chase a trail, and there is no ban on killing rats or rabbits.
And it is thought at least 50 hunts use hounds to flush out foxes to a bird of prey.
And in all these, accidents can happen, with hounds pursuing a live fox.
A spokeswoman for the Countryside Alliance (CA), which had campaigned against
the ban, criticised the report.
"If their claims were true, they would not talk about hunts 'appearing to be' breaking the law."
It has released its own findings that suggest support for the ban has fallen.
A survey, conducted by ORB, a member of the British Polling Society, shows that 45% of those interviewed supported the ban.
The survey is based on the opinions of 1,006 adults in England, Scotland and Wales questioned between 28 and 30 October.
The Alliance said the latest poll marked a significant difference from a Mori poll in July 1999 in which 63% of those questioned supported the ban.
Dr Jane Evans, from the League, said that anti-hunt monitors will be out across the country watching out for any illegal activity.
She said: "It's a historical thing that on the statute books at last we've got a landmark for animal welfare where wild mammals are protected now; People can't chase them, people cannot chase an animal in a protracted, prolonged chase with a pack of dogs now, that it illegal."
© Gigaware™ Ltd 2005