The illegal poisoning of Scotland's birds of prey has hit a 25-year-high, according to a new report.

RSPB Scotland said there were 42 confirmed cases of poisoning in 2006, making it the worst year for bird of prey poisoning in a quarter of a century.

The charity also recorded more than a dozen incidents of bird shooting, nest destruction and the use of traps.

Its latest report identifies a "strong" link between the crimes and the country's sporting estates.

The new figures come weeks after a rare golden eagle was found dead in the Borders The creature, discovered near a grouse moor last month, is thought to have been killed with a poison involving the banned substance carbofuran.

A reward has been offered to find the bird's killer.

RSPB Scotland is calling for tougher punishments for those convicted of bird crime.

Duncan Orr-Ewing, head of species and land management, said: "Many of our birds of prey - golden eagles, red kites and hen harriers - were pushed to or over the brink to extinction by human persecution in Victorian times, linked with the fashion for game preservation.

"The red kite, white tailed eagle, osprey and goshawk, were eliminated completely from Scotland's skies.

"Thanks to conservation efforts and the support of the public, many have now been returned.

"However, some in the community are still carrying out illegal acts designed to kill predators, even though they are fully aware that this is illegal, poses a very real risk to public health and livestock, and has a serious impact on some of our most magnificent birds of prey.

"It is a matter of great shame that in the 21st century such problems are so widespread in certain parts of Scotland.

"It is important to remember that the detection of these crimes is very difficult as they occur in remote areas and difficult terrain, so the figures in this report are likely to represent just the tip of a much larger iceberg."

A total of 98 reports of poisoning were received by RSPB Scotland last year, with 42 confirmed by the Scottish Agricultural Science Agency.

The figure compares to 19 in 2005.