Monitoring Birds and Environmental Influences

A Growing Need for Digital Survey Methods

The Institute for Applied Eco-System Research (IfAÖ) is a privately held research and consulting company in Germany that monitors, analyses and evaluates terrestrial and aquatic ecosystems, since 1993. IfAÖ provides research and consulting services for commercial clients as well as state and federal authorities, especially for the offshore windfarm development sector. Offshore wind farm projects require large-scale ecological surveys before, during, and after construction, in order to assess potential effects on the distribution and abundance of protected species.

Classical aerial visual surveys are limited to low flight altitudes of 250ft. This challenges of real time visual classification/quantification for the observer, disturbance effects on sensitive bird species, and has become a significant safety risk inside wind farms for the crew, due to the rotor-sweep zone of the wind turbines. Aerial surveys, which can be carried out at higher (safer) flight altitudes beyond the swept zone, could technically solve these problems.

The German Federal Maritime and Hydrographic Agency (BSH) has since 2013, required the use of aerial digital imaging methods for assessing the impact of offshore windfarms which has stimulated the refinement of classical survey methods used by the IfAÖ.

Testing the System

The first monitoring test took place in the Pomeranian Bight area of the Baltic Sea in winter when populations of Common Eider, Long-tailed Duck, Common Scoter and Velvet Scoter are extremely high to allow for easy counting and distinguishing of the different species. To test the robustness and the suitability for commercial use, the project included a coverage of 1,500SqKm with 10 flight lines – each of 50km length. The survey was carried out in six hours and 6,300 images were captured from an altitude of 1,400feet above sea level at a cruising speed of 100knots. The system’s performance was robust and the acquisition ensued without any image loss. A later analysis showed good results, which exceeded the team’s expectations in quality and resulted in a high match compared to ship based observations, which ran concurrently. Further test surveys in the spring addressed the limits of light and weather conditions, the detection possibilities for marine mammals and the extension of the survey runtime up to 8 hours a day.