However, thousands of farmers are still waiting for a definitive compensation scheme on lands affected by the EU's protected status for the hen harrier.
Liam O'Keeffe, chairman of the Irish Farmers with Designated Land (IFDL), which represents the hen harrier farmers, is critical of the GLAS solution.
"There's €70m in the LLAES, but if you calculate the 169,000ha designated, I don't think the fund that's there will cover it," he said.
However, Dr Ó hUallacháin, says the green, low-carbon agri-environment scheme - providing for a maximum payment of €5,000 for up to 50,000 farmers, and a further payment of up to €2,000 for a limited number of farmers who take on particularly challenging actions - is offering promising results.
He says the Burren Life Project, a scheme that has paid Burren farmers over €2m to create the conditions for rare and wild flowers over the past six years, is flourishing.
Two hundred farmers were recruited into the Burren Programme in January for a five-year contract with further tranches hoped to double participation.
Burren Life director Brendan Dunford has said the project has had "a phenomenal impact" on the landscape and that the environmental health of the Burren, visited by Prince Charles last summer, is increasing year by year.
Meanwhile, 102 farmers in Offaly and Dublin are undertaking Grey Partridge actions in GLAS. Countryside management specialist at Teagasc Kildalton, Catherine Keena, said: "Farmers have undertaken a measure in GLAS to grow a special 12-metre margin for Grey Partridge so they can move out of Lough Boora bogs where they have been successfully bred and live on its own on farmlands.
Dr Ó hUallacháin says targeting the right farmer is key to the future success of GLAS.
"For some farmers, it's always going to be attractive because they mightn't have to do that much additional work in order to be eligible for certain measures. For other farmers and particularly for more intensive farmers, the schemes weren't attractive enough for them to undertake so it wasn't really worth their while," he said.
"There are reservations and concerns over the level of paperwork involved, also payment rates are relatively low so bigger farmers aren't that pushed," he said. Small farmers with smaller incomes are more likely recruits.
New figures from the Department of Agriculture show that €39m will be paid out on the Agri-Environment Option Scheme (AEOS) this year. AEOS, the predecessor of GLAS, was launched in 2010 as replacement for REPS.
Although conservation ratings among Ireland's grassland habitats are still very poor, Dr Ó hUallacháin, says our typical farming habitats are probably better than EU counterparts.
He says approximately 14pc of average Irish farms are defined as "semi-natural habitats" with streams, small areas of woodland, hedgerows and other areas that haven't been improved from an agricultural point of view.
But species-rich grasslands are seriously suffering.
"High priority habitats aren't being appropriately addressed in some areas which will inevitably lead to loss of species and habitat diversity," he said.
Pollinators and the loss of flower-rich fields are a particular concern, while farmland bird species including the curlew, lapwing and corncrake are also battling extinction with numbers down to less than 100.
Other birds fighting for survival on our grassland and bog habitats include: Bewick's swan, twite, whinchat, dunlin, redshank, golden plover, barn owl and ring ouzel.
"Our most threatened bird species are associated with agriculture. Moves are afoot to reverse this but for certain species it may be too late," Dr Ó hUallacháin added.
"The corncrake has been squeezed out of the midlands and Shannon Callows. Now it's just being left in a few pockets in north Donegal, Mayo, Galway and some offshore islands."
Conversions from hay to silage harvesting have played a detrimental role.
Dr Ó hUallacháin says farmers can improve biodiversity by simply ensuring hedgerows are maintained in an environmentally and ecologically friendly way and by trying to conserve existing terrain.
Opting not to fertilise less productive swampy lands would also help. "Land abandonment where scrub is encroaching grassland species and increased used of fertilisers, pesticides and land drainage are the two main threats to biodiversity from an agricultural point of view," said Dr Ó hUallacháin.
"The biodiversity we have in Ireland is because of agriculture but if we want to maintain them, we need to have active farmers managing the landscape," he said.