Marine mammals can be separated into two groups: cetaceans (such as whales, dolphins and porpoises) and pinnipeds (such as seals). Consideration needs to be given to the marine mammals either living in or migrating through the region of any proposed tidal lagoon. The EIA needs to consider how animals are currently using an area (e.g. feeding/foraging or reproducing).
Marine mammals are potentially affected by the construction, operation and decommissioning of tidal lagoons through a number of pathways including: risk of collision, increased noise, barrier to movement, changes in water quality and changes to foraging habitat or food resource as an indirect impact from alterations in coastal processes.
In order to gain an understanding of the existing environment, prior to any project’s development, surveys can be undertaken to inform the EIA. There are a number of options for surveying marine mammals, the most common of which include: boat-based transect surveys, aerial surveys and acoustic surveys. It is important that the survey programme is tailored to the mammals most likely to be encountered in the area to be surveyed. These surveys, coupled with existing reports and studies, help Tidal Lagoon Power understand the current situation, and therefore better predict the likely impacts arising from the construction, operation and decommissioning of the proposed Project.