Defining the geographic scale of fish species populations, for impact assessments of low carbon energy projects and marine spatial planning

There is currently no common understanding of how best to quantify the spatial scale of fish populations. Such a lack of understanding is likely to lead to a disconnect when quantifying expected impacts to fish populations, which can come from many sources, including fisheries or offshore infrastructure developments. This is because the units used for management and impact assessment (e.g., fished units) and the biological population structure of fish populations, defined by genetic homogeneity and local use of different habitats, may not always correlate. 



To quantify and cover that disconnect, this project collated, examined and provided recommendations on the factors that should be considered to determine, for United Kingdom (UK) fish species, the spatial scale of populations. By undertaking this, the project was designed to provide a framework through which to determine the biologically appropriate spatial scale for quantifying UK fish populations. The project had two main objectives:

Objective 1: Undertaking of a literature review to collate the range of factors that have been utilised to determine the biologically appropriate population scale for fish species. This objective place an emphasis on the range of Life History Traits (LHTs)  that have been utilised to describe/assess the spatial scale of fish populations; and

Objective 2: Providing a method to determine the biologically appropriate spatial scale to quantify UK fish populations, including options for dealing with varying levels of data availability and quality.