Fehmarnbelt Fixed Link
In 2008 Germany and Denmark signed a state treaty with which they agreed upon the construction of a fixed link that would span the 18 km broad Fehmarnbelt and connect Puttgarden (Fehmarn) to Rødby (Lolland, Denmark). The planning and execution of the currently largest infrastructural project in Europe is carried out by Femern A/S. After considering various types of bridges and tunnels during the initial planning stages, the final decision was to build an immersed tunnel.
As part of an international consortium BioConsult SH had been commissioned by Femern A/S, to conduct the baseline investigations on marine mammals, resting birds, bird migration as well as bat migration between 2008 and 2010 for the environmental impact assessment. Additionally, BioConsult SH accompanies the plan approval procedure in Germany.
The environmental impact assessment is based on the following investigations:
Marine Mammals (harbour porpoise, harbour seal, grey seal):
- Description of the occurrence and distribution of harbour porpoises, harbour seals and grey seals by performing monthly aerial surveys (transect and and additional surveys for the recording of seals at their haul-out sites).
- Additional description of harbour porpoise occurrence in the area of the planned construction of the fixed link by performing monthly surveys from onboard the ferry Puttgarden – Rødby.
- Description of the occurrence and distribution of harbour porpoises using C-PODs (acoustic detection of porpoise echolocation signals using specific underwater hydrophones).
- Assessing a possible barrier effect of a bridge on harbour porpoises based on visual (aerial surveys, land-based observations) and acoustic (C-PODs) investigations.
- Investigating habitat use and movement patterns of harbour seals in the Fehmarnbelt area by satellite telemetry.
- Investigation of underwater noise levels in the study area.
- Description of the occurrence and distribution of non-breeding waterbirds by performing monthly aerial surveys (transect and additional surveys for the recording of moulting mute swans).
- Description of the occurrence and distribution of non-breeding waterbird by performing monthly ship-based surveys.
- Investigating the foraging ecology of seaducks (common eider, long-tailed duck, common scoter) in the study area by stomach analysis and VHF radio telemetry.
- Investigating the small and large scale movements of seaducks (common eider, long-tailed duck, common scoter) by satellite telemetry.
Description of bird migration across the Fehmarnbelt based on bird migration observations from two land-based stations close to Puttgarden and Rødby as well as from an offshore location that was based on a ship using:
- Land- and ship-based surveillance radar observations
- Land-based pencil beam radar „Superfledermaus“ in cooperation with the Swiss Ornithological Institute
- Land- and ship-based visual observation of bird migration
- Land- and ship-based night acoustics
- Recording and description of bat migration using stationary recording devices (bat boxes) at various locations along the coast of Fehmarn and Lolland as well as onboard the Scanlines ferries from Puttgarden to Rødby and other ships.
- Recording and description of bat migration using bat detectors along the coast of Fehmarn and Lolland.
In 2015 BioConsult SH performed digital aerial surveys using the HiDef-system in the Fehmarnbelt study area alongside conventional aerial surveys (where an ornithologist counts visually from the aircraft). These surveys were conducted to compare with data collected during the aerial surveys carried out between 2008 and 2010.