Abstract
The main aim of this project was to improve measurements on input parameters of collision risk models, such as the Band model (Band 2012). The focus of our project laid on carrying out measurements on the parameters empirical meso- and macro-avoidance and species specific fluxes. We assessed how birds respond to wind farm Luchterduinen at two different scales (figure 1.2.1), based on the same definitions as used in the ORJIP study (Skov et al. 2018):
1. Macro-avoidance: avoidance of the wind farm as a whole, within an area of 3 km distance from the wind farm up to the rotor-swept zone (and a 10 m buffer around it) of the outermost line of wind turbines;
2. Meso-avoidance: anticipatory or impulsive evasion of rows of turbines within the wind farm up to the rotor-swept zone and a 10 m buffer around it.
The last component of avoidance behaviour, micro-avoidance (i.e. last-second action to
avoid collision with the turbine blades within the rotor-swept-zone and a 10 m buffer around
it) is not part of the current study and will be measured within the MEP-LUD research
conducted by DHI, under the license obligation of Eneco, the owner of Luchterduinen. The
two projects will be integrated in a later phase to provide a complete understanding of bird
fluxes, number of collisions and macro-, meso- and micro-avoidance in the Luchterduinen
wind farm.
In addition, also measurements on the variables flight height and flight speeds were
highlighted as necessary to further improve collision risk models. Besides these main
research questions, we aimed to bring the understanding further on which factors
determine the number, species composition and spatial distribution of birds in and around
wind farm Luchterduinen.
To answer these research questions radar measurements and visual observation were
used. Bird radars are capable of simultaneously tracking multiple birds in a relatively large
area, which cameras or visual observers cannot achieve. The radar database relied mainly
on automatic filtering of the bird radar itself, but also post-processing took place in order to
approach actual bird flight intensities. However, radars do not provide species-specific
information. Therefore, besides monitoring and analysing the radar data, we also collected
species-specific data in Luchterduinen, by carrying out visual observations.