Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Poster Abstract for the ICES Annual Science Conference
Document related concepts
Transcript
Ecological impact of Atlantic mackerel (Scomber scombrus) in Icelandic waters; a multidisciplinary diet analysis. Cecilia E. K. Kvaavik1, 2, 3, Guðmundur J. Óskarsson1, René Groben3, Hildur Pétursdóttir1, Jonathan Grabowski4, Anna Kristín Daníelsdóttir3 and Guðrún Marteinsdóttir2. 1 Marine and Freshwater Research Institute, Reykjavík, Iceland. E-mail: [email protected] University of Iceland, Reykjavík, Iceland 3 Matís, Reykjavík, Iceland. 4 Northeastern University, Nahant, MA, USA. 2 Most pelagic stocks are highly migratory and are particularly likely to demonstrate effects linked to climate change. The mackerel, which started to appear in Icelandic waters in the mid-2000, is now caught in great numbers by the commercial pelagic fisheries of Iceland. Survey abundance estimates indicate that a significant part of the mackerel stock has entered the Icelandic EEZ during its summer feeding migration since then (~1.5 million tons in 2012 and 2013, 1.6 million tons in 2014 and 2.9 million tons in 2015) where they increase in weight by ~43%. This suggests that mackerel feeding in Icelandic waters may be having a significant impact on the pelagic ecosystem. This PhD project is using a combined approach to determine in detail the diet of mackerel that migrate to Iceland during the summer, in an effort to understand the ecological impact that this species may have on the ecosystem. The approach includes analysing visual data supplemented by stable isotope analysis and DNA based species identification to provide a more complete picture of the mackerel’s diet. Stable isotope (δ13C and δ15N) signatures reflect biologically assimilated nutrients from the diet over a long time period. Meanwhile DNA based species identification (RealTime PCR and DNA metabarcoding) enables difficult prey items, such as those that have been partially digested, or juveniles to be identified. The integration of all these analyses will allow a more detailed insight into the diet of mackerel feeding within the Icelandic EEZ.
