HS2 defends its use of specially-trained hawks to stop birds nesting near their construction sites around Leamington and Kenilworth
Protesters said they have seen the pest controllers with their hawks in Broadwells Wood in Warwickshire.
Luci Ryan, lead ecologist for the Woodland Trust, said: “Alarming as it is that a Government scheme would use such a damaging method, and without disclosing it, we’re more concerned about why and what comes next?
"The wood is currently teeming with life - bluebells emerging, badgers busy in their setts and birds prospecting.
“Works should not start until October when the wood is dormant, so it begs the question why attempt to prevent birds nesting now unless contractors wish to bring the bulldozers in this spring?"
An HS2 spokesperson said:“HS2 Ltd contractors are keenly aware of the law around nesting birds, and during nesting season an ecologist is present during all tree clearance work in order to spot nesting birds and stop work where necessary.
“The use of specially-trained hawks is one of a number of efficient and effective tools we have to encourage birds to nest away from our construction sites.
"The hawks are trained not to attack birds and, where possible, decoys attached to poles are also used to ward off smaller birds from nesting.
“Trained hawks have had to be used in Broadwells Wood because the presence of protesters has stopped trees being felled during the winter and before the bird nesting season starts.”
The Woodland Trust added: "While the practice (of using hawks) is, in our opinion, highly dubious the more worrying question is why, when HS2 has publicly committed to translocating soils from this ancient woodland as part of their compensation package.
"This can only be done when the wood is dormant late autumn/early winter.
"Attempting to clear the wood of nesting birds indicates HS2 is intending to fell this wood much sooner. This is completely against what HS2 has committed to do.
An HS2 spokesperson replied: "We’re still working with the team to agree the precise schedule for the translocation."