Analysts from the Scottish Agricultural Science Agency (SASA) have confirmed that 25 carcasses of rabbits and hares laced with deadly Carbofuran were discovered within a one square mile radius in Berwickshire countryside between March and September last year.
They were found on five different occasions over the six-month period alongside six buzzards, two crows and a magpie which had been poisoned after eating the bait - although many more birds may have eaten the bait and died in other locations.
However, there have been no publicity warnings about the discoveries despite the obvious risk to public health from the toxic substance Carbofuran, which was banned in 2001.
There have been no prosecutions and fears have been raised that wildlife crime remains a significant problem in Scotland despite a government crackdown after well publicised previous killings of birds of prey.
The significance of the incident is highlighted by a recent case involving a gamekeeper, who was given 100 hours community service - the direct alternative to custody - and stripped of his shotgun licence for laying out just one poisoned bait at a farm near Kelso.
The gamekeeper last week attempted to get his firearms certificate back by taking the chief constable of Lothian and Borders Police to court.
It is the large scale nature of this latest case in Berwickshire within such close proximity and no-one being held to account which has dismayed wildlife crime investigators.
A member of the public first informed Lothian and Borders Police in March 2007 that poisoned baits were being left out in the open air on an estate near Greenlaw.
A search took place but it is understood issues over land-ownership may have complicated the operation and no-one was held to account for the poisonings.
The samples were sent to Edinburgh-based SASA, a government agency, where scientists have now confirmed carcasses were submitted for analysis from the Greenlaw area on five separate occasions during March and September of 2007.
All the poisoned rabbit and hare baits were found within a one square mile radius.
Investigators cannot recall so many poisoned baits being recovered from one particular location in Scotland.
Doreen Graham, spokeswoman for the Scottish Society for the Prevention of Cruelty to Animals, said: "We are concerned at the large number of poisoned baits found at Greenlaw in Berwickshire.
"Carbofuran is an illegal substance and we believe the only people who still have access to quantities of the substance are well aware that they are breaking the law. In its granular form, one grain of Carbofuran will kill a bird.
"A total of 25 poisoned baits were found, but because wildlife frequently hides away to die, there are possibly other victims that have never been found.
"The Scottish Borders is rich in wildlife, but how many more golden eagles, red kites or -because poison is indiscriminate - family pets, have to die.
"The use of poisoned bait is cruel and illegal and all the agencies must continue to work together to stop the individuals who could rob Scotland of one of its most important assets - its wildlife."
She added: "The public are our eyes and ears when it comes to wildlife crime which is why we have set up a dedicated hotline for information - which is manned 24 hours a day - so we can gather intelligence.
"It also offers rewards of up to £1,000 leading to a conviction."
A spokesman for the Royal Society for the Protection of Birds (RSPB) said: "This staggering level of illegal activity goes to show that poisoning is sadly still considered par for the course by some people in Scotland.
"Far from being on the wane, the last two years have seen some of the highest levels of such crimes being detected.
"We urge anyone with information relating to these crimes to contact the police, and look forward to hearing the results of police investigations."
A Scottish Government environment spokesman said: "We, of course, deplore the dangerous and cruel practice of leaving poisoned baits around the Scottish countryside.
"Investigation of these crimes is a matter for the police."
A Lothian and Borders Police spokeswoman could not give a reason why there had been no publicity issued following the discovery of the poisoned baits.
But she added the cases were notoriously difficult to prosecute due to the lack of witnesses in rural areas such as the estates around Greenlaw.
The spokeswoman said: "There have been a number of searches in the area during the year.
"These incidents are taken very seriously and we would welcome any information on the matter."
The death of six buzzards follows a similar high profile death of a bird of prey in the Scottish Borders last August when one half of a breeding pair of golden eagles was killed.
The pair were introduced by RSPB Scotland but the female eagle died after eating bait laced with Carbofuran, the same substance that was involved in the poisoned carcasses at Greenlaw.
Anyone with information on the poisoned bait around Greenlaw should contact the police or the Scottish SPCA on their special hotline number - 0870 2404832.