Fehmarnbelt Fixed Link
On behalf of Femern A/S, BioConsult SH accompanies the German plan approval procedure for the construction of the Fehmarnbelt Fixed Link between the islands of Fehmarn and Lolland.
Europe's largest infrastructural project
In 2008, Germany and Denmark signed a state treaty for the construction of a fixed link spanning the 18 km broad Fehmarnbelt and connecting Puttgarden (Fehmarn) with Rødby (Lolland, Denmark).
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 made to build an immersed tunnel.
Between 2008 and 2010, BioConsult SH has, as part of an international consortium, carried out the baseline surveys for marine mammals, resting birds, bird migration as well as bat migration for the environmental impact assessment.
In a plausibility check in 2015, BioConsult SH simultaneously carried out digital aerial surveys of marine mammals and birds using the HiDef-system and conventional aerial surveys (where an ornithologist counts visually from the aircraft) to ensure comparability. These surveys served to verify the results of the baseline surveys carried out between 2008 and 2010.
Environmental impact assessment
The environmental impact assessment for the individual features of conservation interest was 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 additional surveys to record seals at their haul-out sites)
- Additional description of harbour porpoise occurrence in the area of the planned fixed link by performing monthly surveys from onboard the ferry from Puttgarden to Rødby
- Description of the occurrence and distribution of harbour porpoises using C-PODs (acoustic detection of porpoise echolocation signals using specific underwater hydrophones)
- Assessment of a possible barrier effect of a bridge on harbour porpoises based on visual (aerial surveys, land-based observations) and acoustic (C-PODs) investigations.
- Investigation of habitat use and movement patterns of harbour seals in the Fehmarnbelt area by satellite telemetry
- Investigation of underwater noise levels (noise emissions) in the study area
- Description of the occurrence and distribution of different non-breeding waterbirds by performing monthly aerial surveys (transect and additional surveys to record moulting mute swans)
- Description of the occurrence and distribution of non-breeding waterbird by performing monthly ship-based surveys
- Investigation of the foraging ecology of seaducks (common eider, long-tailed duck, common scoter) in the study area by stomach analysis and VHF radio telemetry
- Investigation of 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 based on a ship using:
- Land- and ship-based surveillance radar observations
- Land-based pulse-radar fire control system “Super Fledermaus” in cooperation with the Swiss Ornithological Institute
- Land- and ship-based visual observations of bird migration
- Recording of flight calls at night
- Recording and description of bat migration using stationary recording devices (bat recorders) at various locations along the coasts of the islands of Fehmarn and Lolland as well as onboard the Scanlines ferries from Puttgarden to Rødby and own vessels
- Recording and description of bat migration using bat detectors along the coasts of the islands of Fehmarn and Lolland
Papers and reports
Individual-based modelling supports environmental impact assessment in a large-scale construction project
Environmental Impact Assessment Review 101 (2023) 107150. https://doi.org/10.1016/j.eiar.2023.107150
Comparison of digital video surveys with visual aerial surveys for bird monitoring at sea
Journal of Ornithology (2019) 160:567–580
Current results and detailed method descriptions of construction phase monitoring for the Fehmarnbelt immersed tunnel are available via the Femern A/S environmental portal. Next to BioConsult SH's waterbird and marine mammal surveys, data and models of further investigations can be found here.