204560Edited by MartynC.110012860layer_information_pageund1449064513146246021300146246021355<p>The three layers show the spatial variation of demersal fish (generally living on or near the seabed) in waters around Scotland (averaged over the period 1999 to 2008) for:</p> <ul> <li>Size Composition (Large Fish Indicator) (defined as the proportion of fish (by weight) in the community that is greater than 40 cm in length). The higher the value (varying between 0 and 1), the greater the proportion of large fish in the community.</li> <li>Species Richness (a count of the number of demersal fish species recorded in any survey sample).</li> <li>Species Diversity (indices that also take account of the relative abundance of each species in the sample).</li> </ul> <p><strong>Date of Data:</strong> 1999-2008.</p> full_html<p>The three layers show the spatial variation of demersal fish (generally living on or near the seabed) in waters around Scotland (averaged over the period 1999 to 2008) for:</p> <ul> <li>Size Composition (Large Fish Indicator) (defined as the proportion of fish (by weight) in the community that is greater than 40 cm in length). The higher the value (varying between 0 and 1), the greater the proportion of large fish in the community.</li> <li>Species Richness (a count of the number of demersal fish species recorded in any survey sample).</li> <li>Species Diversity (indices that also take account of the relative abundance of each species in the sample).</li> </ul> <p><strong>Date of Data:</strong> 1999-2008.</p> 331392FishHouseScotia01.jpgpublic://FishHouseScotia01.jpgimage/jpeg6255411449678712imagecaught fish are sorted in the fish house of the MRV Scotiacaught fish are sorted in the fish house of the MRV ScotiaFish House Scotia - Copyright © Marine ScotlandFish House Scotia - Copyright © Marine Scotland<_drafty_revision_requested>FIELD_LOAD_CURRENTcaught fish are sorted in the fish house of the MRV Scotia533800815<p>Scientific trawl surveys data have been used to assess change in the status of the fish communities. The data collected generate quantitative measures of particular characteristics of the fish community, and these can be used to monitor change in those characteristics over time and between different places. These measures are referred to as community indicators.</p> <p>Over 240 species of fish inhabit the seas around Scotland. For Scotland’s Marine &nbsp;Atlas Marine Scotland undertook an investigation into the state of the demersal fish community in Scottish waters. The work employed a similar approach to comparable assessments for the UK's Charting Progress 2 and OSPAR's Quality Status Report. More information is available in the Demersal Fish Community Atlas link above.</p> <p>All three aspects of the composition and structure of the demersal fish community, proportion of large fish, species richness and species diversity, vary markedly across Scottish waters. For example, fish greater than 40 cm in length constituted a much greater proportion of the biomass of demersal fish in western waters than in regions to the east of Scotland.</p> <p>&nbsp;</p> full_html<p>Scientific trawl surveys data have been used to assess change in the status of the fish communities. The data collected generate quantitative measures of particular characteristics of the fish community, and these can be used to monitor change in those characteristics over time and between different places. These measures are referred to as community indicators.</p> <p>Over 240 species of fish inhabit the seas around Scotland. For Scotland’s Marine  Atlas Marine Scotland undertook an investigation into the state of the demersal fish community in Scottish waters. The work employed a similar approach to comparable assessments for the UK's Charting Progress 2 and OSPAR's Quality Status Report. More information is available in the Demersal Fish Community Atlas link above.</p> <p>All three aspects of the composition and structure of the demersal fish community, proportion of large fish, species richness and species diversity, vary markedly across Scottish waters. For example, fish greater than 40 cm in length constituted a much greater proportion of the biomass of demersal fish in western waters than in regions to the east of Scotland.</p> <p> </p> 5314134751347613477419641975070888sioc:Itemfoaf:Documentdc:datedc:createdxsd:dateTimedate_iso8601dc:modifiedxsd:dateTimedate_iso8601content:encodedsioc:has_creatorrelfoaf:namesioc:num_repliesxsd:integersioc:last_activity_datexsd:dateTimedate_iso8601https://marine.gov.scot/?q=information/demersal-fish-community-spatial-variation-size-species-richness-and-diversity079692045612860publishedpublished55146246021311146246021379692045612860publishedpublished55146246021311146246021379692045612860publishedpublished551462460213111462460213