Understanding Avian Collision Rate Modeling and Discussing what this Means in a Population Context at Land-Based and Offshore Windfarms

Webinar #3 in WREN Environmental Webinar Series
April 2, 2015

Summary
Wind farms can impact birds through collisions, barrier effects and displacement and habitat loss. Of these, collisions have attracted the most attention as the effects of direct mortality are considered to have the greatest potential to impact bird populations.

Onshore we can monitor collisions post-construction through victim searches, offshore this is more challenging although methodologies are being developed that may allow us to collect these data. However, in order to be able to minimize impacts on the environment, we need to understand the risks to birds prior to construction. To do this, collision rate models have been developed that allow us to estimate the perceived risk to birds and the potential number of collisions within proposed wind farms.

These models combine our understanding of bird behavior with the characteristics of the proposed turbines and wind farm layout in order to assess the likelihood of any bird encountering and colliding with a turbine. Having estimated the likely collision rate, it is important to consider what this means in a population context. Several approaches have been proposed for this, notably Population Viability Analysis (PVA) and Potential Biological Removal (PBR). However, the outputs from these models must be interpreted with care, and with consideration of the legislative background of the planning process (WREN Introductory Slides).

Understanding Avian Collisions Rate Modelling and Application at the Population Level

Aonghais Cook has worked for the British Trust for Ornithology (BTO) since completing his PhD at Newcastle University in November 2008. The interactions between birds and renewable energy have been a key focus of his work at the BTO and one of the first projects he worked on was investigating the impacts of a tidal barrage proposed for the Severn Estuary on waterbirds. Since then, offshore wind farms, and, in particular collision risk, has been a key focus of his work. This has included providing guidance to industry as well as to government advisors and regulators, and carrying out impact assessment work for the proposed Dogger Bank wind farm zone in the North Sea. Follow him on twitter: @AonghaisC

Mark Collier currently works as a bird ecologist at Bureau Waardenburg: a leading ecological consultancy in the Netherlands. Originally from Britain, Mark studied applied ecology and conservation at the University of East Anglia (UK) and worked for both the Royal Society for the Protection of Birds and the British Trust for Ornithology before moving to the Netherlands in 2008. Since being at Bureau Waardenburg, Mark has been involved with various ornithological projects including radar studies, satellite tracking and wind farm studies, both on land at sea. Mark has a particular interest in collision risk modeling and has carried out a range of studies including the appropriate assessments of more than 20 offshore wind farms in the North Sea, research into the first Dutch offshore wind farm and the cumulative effects of multiple offshore wind farms. Mark has also used radar and observational data to calculate avoidance rates in an offshore wind farm.

A video recording of the webinar has been posted below: