For the first time in Estonia a white-tailed eagle was injured at a wind power farm. In Lääne county, at the outskirts of the Aulepa wind power farm in Noarootsi parish, an injured adult white-tailed eagle was found on May 20th.
At first the bird was observed at the outskirts of the wind power farm about a hundred meters away from the first power turbine on a low tree branch, later local inhabitants saw the bird on the ground nearby and it became clear that the eagle was not able to fly. The next morning members of the Eagle club captured the bird and arranged its transport to Tartu, to the Veterinarian clinic of the Estonian University of Life Sciences. On examination there it turned out that the eagle lacked parts of the primaries of the left wing together with the digit bones (wing tip bones), and that the injury had occurred about a week ago.
Taking in account the injury established at the examination and the place where the bird was found it can be clearly concluded that a collision with a wind turbine blade had proved disastrous for the bird. The blade tip of a wind power turbine can move at very great speeds, reaching several hundred kilometres per hour, and is sharp enough to cause the described blunt cut-off of the eagle’s wing tip.
The now found white-tailed eagle is a female, who was ringed in 1999 in western Latvia. She has been breeding from 2007 onwards in a nest at about 7 kilometres’ distance from the Aulepa wind farm. In the course of this year’s nest inspections only the male was seen at the nest. There were two chicks in the nest whose status the Eagle Club will be monitoring during the following month.
Eagles and other birds with a large wing span who circle with rising airflows have difficulties in spotting the rapidly moving blades of wind turbines. Thus wind turbines must not be built closer to the nests of rare birds than 2 km (all eagle species and black stork) nor between eagle nests and their main foraging areas. It is not recommended that wind power generators be located on the shore or close to it, since the shore areas are often used by sea eagles for food foraging. With location further away from the shore the risk of birds perishing is smaller.
In the present case the choice of site for the Aulepa wind farm is one of the least dangerous of the present wind farms in Estonia since its power generators are at a distance of 2-5 kilometres from the shore, and the nearest inhabited eagle nest is at a distance of 6 km. However, there is a risk for the birds of chance collisions with the 16 large windmills there. The present case confirms the negative influence of wind turbines on endangered species, particularly birds of prey.
Text and photo: Renno Nellis, Kotkaklubi, EOÜ and ELF
28.05.2013 – 17:43 | website: http://www.looduskalender.ee