One of the greatest mysteries of Irish agriculture has been more or less resolved by a team of research students studying the damage caused by birds to silage bales.
Crows, rooks and jackdaws are drawn to the large black-wrapped bales of winter fodder commonly seen in fields in the countryside.
Farmers often paint symbols or messages on the bales to keep the birds off.
The birds peck holes in the plastic layers around the preserved grass, causing tens of thousands of pounds worth of damage by letting air in.
Over eight million bales of silage are made annually.
It emerged yesterday at the Grange 2000 Teagasc National Beef Open Day that painting the bales does not help keep the birds away unless the message is very specific.
Painting messages like "Up Meath", faces, snakes, the outline of a cat or a man are no good, according to Kieran McNamara, who is working on the problem at the Teagasc Grange Beef Research Centre in Co Meath.
At the open day, Kieran was besieged by farmers asking only one question: "Does painting messages on bales do any good at all?"
Kieran, who is doing a PhD on the subject of wildlife damage to bales, was very clear in his answer.
Painting does work, but farmers must paint a giant eye on the bale to frighten off the birds.
Butterflies protect themselves from preying birds by having a large eye-like image on their wings, and farmers could do the same by painting large eyes on their bales.
This has been found to work in the US and Canada.
Research has shown that painting eyes on the bales can reduce the damage caused by the birds to less than 20 per cent, and this would be a considerable saving for farmers.
Clare-born Kieran said that on 300 farms surveyed by the research team, 64 per cent of them had suffered damage to baled silage from crows, jackdaws, rooks or other birds.
He found that the main destruction was caused by young birds which he called "juvenile delinquents" hanging around waiting to be fed by their parents.
He told farmers that in order to protect their bales they should store them on their ends rather than on their sides, well away from fields which had been harvested, because this attracts feeding adult birds, and paint giant eyes on the surface.
He said other research had shown that different-coloured plastic wrapping did not reduce the damage and that farmers who used green plastic suffered a great deal more damage.
The beady eye is your only man.