Pictured above is part of a Northampton forest that was felled for biofuel in an operation one conservationist has called 'a disgrace'.
Members of a Northamptonshire conservation team say the area is home to great crested newts, bats and breeding birds but has now been 'cleared' in disregard for any survey, they say.
But the Forestry Commission say the land in Denton Wood, pictured, was subject to a 'thorough survey' for protected species and say the felling is 'likely to have positive environmental benefits'.
A spokeswoman for the Forestry Commission said: "We look after the nations’ forests for people, wildlife and timber and work hard to ensure we strike the right balance so that our woodland environment remains a place where birds and other wildlife can thrive.”
Denton Wood, south of Denton, is owned by Castle Ashby Compton Estates while the trees are managed by the Forestry Commission. It is closed to the public.
Bird nesting season in the UK began in February and runs until August. The Wildlife and Countryside Act stresses that clearance work should not be carried out in this period to protect bird nests and their eggs.
Jeff Blincow, a member of the Yardley Chase Conservation Team, which has access to Denton Wood, said: "When I first saw the clear-felled area, there was a single tree left with a Goldcrest sat on it calling to its mate. It was a crying shame.
"There is no reason to do this work now. It could have easily waited until nesting season was over.
"Wild bird nests and eggs are being destroyed as well as other wildlife that is at an important stage in their life-cycles. They want to make money out of the forest and it suits them not to know what damage they are doing."
Castle Ashby, who own the land, harvest wood from their estates to make biomass fuel for their own residential and commercial properties.
A Forestry Commission spokeswoman said: “Our team carried out a thorough survey of the area, particularly for protected species and ground nesting birds, excluding them from the operation. Exclusion zones were also applied around two ponds where we believed Great Crested Newts were present.
"This harvesting work is likely to have positive environmental benefits allowing more light into the grassy areas and helps us to replant some of the dying trees."
But Mr Blincow said: "You're telling me they surveyed that entire area and decided there were no nesting birds there? It's a disgrace."
A spokeswoman from the Wildlife Trust for Northamptonshire said: "We are aware of felling taking place at Denton Wood and have written to the chief executive of Forest Enterprise, an agency of the Forestry Commission, who are carrying out the works, expressing concerns of this happening during the bird breeding season.
"As a Wildlife Trust we find it difficult to see how an area of woodland such as this is unlikely to have any active bird nests or even summer bat roosts at this time of the year, and therefore how the Wildlife and Countryside Act cannot have been contravened, resulting in a wildlife crime.
"We are awaiting results and methodologies of the ecological surveys undertaken by the Forest Enterprise. Should this indicate a wildlife crime has been committed, then the Wildlife Trust will ensure the appropriate authorities are informed and action is taken."