Marine mammal mortality and adverse effect on site integrity

This position defines what we consider to be the levels of marine mammal mortality or removals permissible without causing an adverse effect on site integrity (AEOSI) as part of a habitats regulations assessment (HRA).

As a developer or consultant, you can use the position to help submit applications with enough information to allow the competent authority to assess sites with marine mammal features.

NRW considers that only a small number of marine mammal removals would be permissible in any year before being unable to rule out AEOSI. These are defined in the position.

NRW’s position on determining adverse effect on site integrity for marine mammal site features in Wales in relation to potential anthropogenic removals (mortality) from marine developments