Thomson Ecology was commissioned by Network Rail to ascertain the presence of any nesting birds, in particular peregrine falcons, (Falco peregrinus) on
a viaduct in North Yorkshire.
Network Rail proposed to undertake railway sleeper alignment along the track on the viaduct, and Thomson Ecology was asked
to provide recommendations for action or controls to ensure that any nesting birds would not be disturbed during development works.
The viaduct was observed from a vantage point at a suitable distance to ensure that there would be no disturbance to any nesting birds present. Jackdaw (Corvus monedula) and stock
dove (Columba oenas) were observed entering seepage holes within the stonework of the span supports, and a peregrine falcon was seen perched and preening,
and later flying off and returning with a kill, which it de-feathered and ate on the ledge.
Peregrines have suffered illegal killing by gamekeepers and landowners, and have been a target for egg collectors, but better legal protection for the species and control of pesticides, which can indirectly poison
birds, have helped the population to recover considerably. All breeding birds, active nests and eggs are protected by the Wildlife and Countryside Act
1981 (as amended), and peregrine falcons receive additional protection under Schedule 1 of the act. Intentional and reckless disturbance of peregrine falcons
when nesting or when they have dependant young is illegal, and any such offence against peregrine falcons can attract fines of up to £5,000 per offence
and/or a custodial sentence of up to six months.