Single Nucleotide Polymorphisms Are Suitable For Assessing The Success of Restocking Efforts of The European Lobster (Homarus Gammarus, L.)

Abstract

The European lobster (Homarus gammarus) forms the base of an important fishery along the coasts of Europe. However, stocks have been in decline for many years, prompting new regulations in the fishery and also restocking efforts. An important feature of any restocking effort is the assessment of success in the number of released juveniles that stay and become adult over time. Here, we tested the power of a SNP DNA marker panel developed for population assignment to correctly infer parentage on the maternal side of lobster larvae, in the absence of known fathers, using lobsters included in a current restocking effort on the Swedish west coast. We also examined the power to reconstruct the unknown paternal genotypes, and examined the number of fathers for each larval clutch. We found that the 96-SNP panel, despite only containing 78 informative markers, allowed us to assign all larvae to the correct mother. Furthermore, with 10 genotyped larvae or more, confident paternal genotypes could be reconstructed. We also found that 15 out of 17 clutches were full siblings, whereas two clutches had two fathers. To our knowledge, this is the first time a SNP panel of this size has been used to assess parentage in a crustacean restocking effort. Our conclusion is that the panel works well, and that it could be an important tool for the assessment of restocking success of H. gammarus in the future.

European lobster Homarus gammarus aquaculture: Technical developments, opportunities and requirements

“…Commercial hatchery (dark circles) and aquaculture initiatives for release or production (open circles) active or planned between 2000 and 2020. For details, please refer to accompanying table 17,28,37,49,59,60,67,69,77,92,100,119,131,137–146 . Short term research projects not included…”

“…2021). Larger scale commercial roll‐out in the future will be guided using a dedicated roadmap, with similar technology recently piloted in Sweden and the Republic of Ireland 58,59 …”

“…Combining release strategy improvements with an accurate understanding of localised post release survival is still not routinely employed, undoubtedly owing to technical and economic challenges associated with conventional mark‐recapture of small hatchery juveniles 128 . More recently, genetic profiling (microsatellite identification) has been performed on H. gammarus , alongside a recent discovery that egg clutches originate mostly from singly‐sired paternity, potentially in at least two discrete lobster populations 59,126 . This may enable parentage assignment and allow identification of hatchery‐reared lobsters to appraise stocking success 9,126,129 .…”