Impacts of Wave and Tidal Energy on Seabirds

Posted by Sara King BSc (Hons) AIEEM on 13/12/2012

One of the main sources of this renewable energy will be from wind turbines, and extensive research has been undertaken to assess the impacts of wind farms on wildlife, particularly bird species. Another source of renewable energy currently under development is wave and tidal energy. Awareness of impacts on seabirds as a result of these schemes are not so widely publicised, and limited research has been undertaken to assess the impacts of these schemes of the UK’s seabird populations.

The UK hosts a seabird assemblage of outstanding international importance. Wave and tidal energy schemes are being developed around the UK, and therefore the potential impacts on seabirds are an increasingly relevant and important consideration. Potential impacts can include collision, disturbance, habitat exclusion and displacement, changes to sedimentary processed and pollution. Bird surveys would be required to inform a proposed tidal or wave energy scheme. The aim of the surveys would be to determine the species, current use, and the number of seabirds using the site. Information obtained from the bird surveys undertaken would inform the impact assessment and the scheme design.

Impacts on seabirds as a result of wave and tidal schemes varies depending on species, behaviour and location. The RSPB state that some species can avoid tidal energy schemes, based on research from existing wind farm schemes. Other species are more prone to collision due to their foraging behaviour. The highest risk of impacts such as collision and disturbance are associated with schemes that are located within foraging range and within areas used by high numbers of seabirds. Other impacts include habitat displacement, which is likely to result in increased competition for prey within adjacent foraging areas, therefore affecting adjacent populations. Consideration therefore needs to be given to the impact of the scheme on a wider area than the site itself.

Design is important when assessing the impacts on seabirds. The RSPB state that above surface structures are more likely to be detected and therefore avoided by seabirds. Below surface structures that are within foraging range may be undetected by diving birds, therefore are more likely to result in collisions. Devices which use underwater turbines are also likely to pose a greater threat to seabirds. Wave and tidal energy devices can provide additional opportunities for wildlife, and the impacts may not all be negative. Above surface structures can create new roosting points for seabirds, and below surface structures may provide artificial reef habitats. However, research into the benefits of these structures is limited, and it is unlikely that the positive outcomes will outweigh the negative.

Further research is required to determine the impacts of increase wind and tidal energy schemes begin developed in the UK. Whilst there is a need for increased renewable energy, the industry will need to continue to adapt as research provides a greater understanding of the impacts of schemes on seabirds.   For more information, the RSPB have published a paper relating to the impacts of wave and tidal energy on seabirds.