2018
 

Population genetic structure after 125 years of stocking in sea trout (Salmo trutta L.)

År: 2018

Population genetic structure after 125 years of stocking in sea trout (Salmo trutta L.)

Petereit, C., Bekkevold, D., Nickel, S., Dierking, J., Hantke, H., Hahn, A., Reusch, T. & Puebla, O. 20 Jun 2018 In : Conservation Genetics.

Publication: Research - peer-reviewJournal article – Annual report year: 2018

Stocking can be an effective management and conservation tool, but it also carries the danger of eroding natural population structure, introducing non-native strains and reducing genetic diversity. Sea trout, the anadromous form of the brown trout (Salmo trutta), is a highly targeted species that is often managed by stocking. Here, we assess the present-day population genetic structure of sea trout in a backdrop of 125 years of stocking in Northern Germany. The study area is characterized by short distances between the Baltic and North Sea river watersheds, historic use of fish from both watersheds for stocking, and the creation of a potential migration corridor between the Baltic and North Sea with the opening of the Kiel Canal 120 years ago. A survey of 24 river systems with 180 SNPs indicates that moderate but highly significant population genetic structure has persisted both within and between the Baltic and North Sea. This genetic structure is characterized by (i) heterogeneous patterns of admixture between the Baltic and North Sea that do not correlate with distance from the Kiel Canal and are therefore likely due to historic stocking practises, (ii) genetic isolation by distance in the Baltic Sea at a spatial scale of < 200 km that is consistent with the homing behaviour of sea trout, and (iii) at least one genetically distinct Baltic Sea river system. In light of these results, we recommend keeping fish of North Sea and Baltic Sea origin separate for stocking, and restricting Baltic Sea translocations to neighbouring river systems.

Original languageEnglish
JournalConservation Genetics
ISSN1566-0621
DOIs
StateAccepted/In press - 20 Jun 2018

 

Earlier hatching and slower growth, a key to survival in the early life history of Norwegian spring spawning herring

År: 2018

Earlier hatching and slower growth, a key to survival in the early life history of Norwegian spring spawning herring

Slotte, A., Husebø, Å., Berg, F., Stenevik, E. K., Folkvord, A., Fossum, P., Mosegaard, H., Vikebø, F. & Nash, R. D. M. 2018 In : Marine Ecology Progress Series.

Publication: Research - peer-reviewJournal article – Annual report year: 2018

Original languageEnglish
Book seriesMarine Ecology Progress Series
ISSN1616-1599
DOIs
StateAccepted/In press - 2018

 

A call for a paradigm shift: Assumed-to-be premature migrants actually yield good returns

År: 2018

A call for a paradigm shift: Assumed-to-be premature migrants actually yield good returns

Birnie-Gauvin, K. & Aarestrup, K. 2018 In : Ecology of Freshwater Fish.

Publication: Research - peer-reviewJournal article – Annual report year: 2018

Animals with complex life cycles often display plasticity in the timing of transitions across life stages. The brown trout, Salmo trutta, highlights such phenotypic plasticity with its alternative migratory tactics. Downstream migration of smolts exemplifies one of the many ways in which brown trout display plasticity. The timing of this migration is assumed to be in the spring, although recent evidence suggests an autumn migration is also present. While the proximate and ultimate causes for this autumn migration remain unclear, it was hypothesised that leaving in the autumn may have short‐term benefits (e.g., lower competition) but that these individuals are maladapted to life at sea and yield poor adult returns. To test this hypothesis, 1370 wild juvenile brown trout from a Danish stream were tagged with PIT tags. Individuals were then divided into autumn and spring migrants depending on the timing of their outmigration to saltwater, and their return to freshwater was followed. Inconsistent with the hypothesis that autumn migrants yield poor returns, our findings suggest that autumn migrants yield similar return rates to spring migrants, with no observed differences in length, mass and condition upon tagging, nor in average time spent at sea. Our findings suggest that autumn migrants may not be maladapted to marine environments in a way that affects their survival, and call for a paradigm shift in the current description of the brown trout lifecycle
Original languageEnglish
JournalEcology of Freshwater Fish
ISSN0906-6691
DOIs
StateAccepted/In press - 2018

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Working together: collaborative decision making for sustainable Integrated Coastal Management (ICM)

År: 2018

Working together: collaborative decision making for sustainable Integrated Coastal Management (ICM)

Gillgren, C., Støttrup, J. G., Schumacher, J. & Dinesen, G. E. 2018 In : Journal of Coastal Conservation.

Publication: Research - peer-reviewJournal article – Annual report year: 2018

Community involvement and genuine engagement with citizens is an important, integral element of the Systems Approach Framework (SAF). The SAF provides a structure for an Integrated Coastal Management (ICM) process using a multidisciplinary approach that integrates environmental, social and economic viability and well-being. An assessment of the SAF and its application with respect to citizen engagement and participation uncovered two main issues: (i) the implications of engaging stakeholders have not been fully understood and are still not an integral part of the SAF ICMprocess; and (ii) the need to include
validation. This article sets out to address these issues. It explores the paradigm shift in government-citizen interaction that moves from a management Boutputs^-based approach to a more collaborative partnership approach focused on Boutcomes^. This shift necessitates a more robust public participation framework that is timely, iterative and genuinely inclusive. Without community and stakeholder Bbuy-in^ it is difficult to achieve the behavioural change necessary to achieve sustainability. Engagement considerations should be addressed from the outset and throughout the process to the Implementation^ and BMonitoring and Evaluation^ steps. Furthermore, this paper identifies the need to move beyond these steps to include validation in the SAF, especially when dealing with highly complex issues. In this way, citizens take ownership of the issue(s), participate in identifying solutions and strive to maintain sustainable development. This paper provides the necessary input to how the SAF can integrate credible public participation for outcomes that are more successful and lead to greater sustainability and improved social capital
Original languageEnglish
JournalJournal of Coastal Conservation
ISSN1400-0350
DOIs
StateAccepted/In press - 2018


http://www.aqua.dtu.dk/Om_DTU_Aqua/Publikationer
21 JULI 2018