A new study involving researchers from BIOVIT can help detect and monitor interbreeding between native European lobsters and introduced American lobsters.
The findings have important implications, since increased interbreeding with American lobsters may affect the long-term conservation of native European lobster populations in Norway and elsewhere in Europe.
The study, recently published in the journal G3: Genes|Genomes|Genetics, tested a set of 79 genetic markers to see how well they can distinguish European lobsters, American lobsters, and hybrids – i.e. offspring from one or more generations of breeding between the two species.
Such hybrids have been historically difficult to detect, especially over multiple generations where the cross-species breeding took place between more distant ancestors. Often detection relies on physical traits, which is a more error-prone approach compared to objective DNA analyses.
The new study shows that the genetic marker set works well for identifying European lobsters, American lobsters, and first-generation hybrids.
Unsurprisingly, the 79 markers were less reliable for identifying later-generation hybrids, especially when only a small proportion of American lobster ancestry remained.
Lead author Erik Sandertun Røed completed his PhD project at BIOVIT investigating genetic methods for improved conservation of European lobster
The results provide practical guidance for genetic monitoring and managing populations, for example in the conservation of native lobster populations in the Oslo fjord. The marker set can be useful for rapid screening and for detecting recent cross-species breeding, but results suggesting low levels of American lobster ancestry need to be interpreted carefully.
The study was led by Erik Sandertun Røed, who received NMBU’s award for the best master’s thesis of 2024 for his research on genetic methods for European lobster conservation. His PhD project was supervised by Marie Saitou (BIOVIT), and combined field sampling, laboratory work, genetic analysis, and computer simulations towards monitoring lobster populations in the Oslofjord.
The research was supported by the Norwegian Directorate of Fisheries through the Tilskudd til fiskeriforskning scheme, with additional support from the Finn Jørgen Walvig Foundation. Marie Saitou was supported by the NMBU Research Talent Programme 2021, and the work also featured collaborators and financial support from from the University of Exeter, UK, and the GENECO doctoral network.
The article is available in full on the G3: Genes|Genomes|Genetics journal website.