Publications

Here you will find publications from DTU Aqua:

Recent publications

2017
 

A comparison of the survival and migration of wild and F1-hatchery-reared brown trout (Salmo trutta) smolts traversing an artificial lake

Year: 2017

Supplementing salmonid populations by stocking is a widely-used method to improve catch or to rehabilitate populations. Though, most studies found that survival and fitness of hatchery-reared salmonids is inferior to wild fish. We compared survival, emigration patterns, migration speed and return rates from the sea of wild and 1-year old F1-hatchery-reared brown trout smolts in a Danish lowland stream that contains an artificial lake using passive integrated transponder telemetry in the years 2011–2013 and 2016. The majority of hatchery-reared smolts descended within 72 h after their release, whereas wild fish migration was mainly triggered by increased water discharge. Increased probability of a successful lake passage was found at higher discharge. Within years, the groups differed in lake passage time, but without a significant overall difference. Overall, there was no difference in lake survival (wild: 30%, hatchery-reared: 32%) between the two groups, but survival differed between years. Only a single fish (0.9%) of the hatchery-reared smolts tagged in 2011–2013 returned from the sea compared to 11 (6.4%) wild smolts tagged in that period, which questions the value of supplementary stocking of smolts for conservation purposes.

Original languageEnglish
JournalFisheries Research
Volume196
Pages (from-to)47-55
ISSN0165-7836
DOIs
StatePublished - 1 Dec 2017

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Registrering af fangster i de danske kystområder med standardredskaber. Nøglefiskerrapport 2014-2016

Year: 2017

Original languageEnglish
PublisherInstitut for Akvatiske Ressourcer, Danmarks Tekniske Universitet
Number of pages134
ISBN (print)978-87-7481-239-5
ISBN (electronic)78-87-7481-238-8
StatePublished - 2017
SeriesDTU Aqua-rapport
Number320-2017

 

Envisioning the future of aquatic animal tracking: Technology, science, and application

Year: 2017

Envisioning the future of aquatic animal tracking: Technology, science, and application

Lennox, R. J., Aarestrup, K., Cooke, S. J., Cowley, P. D., Deng, Z. D., Fisk, A. T., Harcourt, R. G., Heupel, M., Hinch, S. G., Holland, K. N., Hussey, N. E., Iverson, S. J., Kessel, S. T., Kocik, J. F., Lucas, M. C., Flemming, J. M., Nguyen , V. M., Stokesbury , M. J. W., Vagle , S., Vanderzwaag, D. L., Whoriskey, F. G. & Young , N. 2017 In : BioScience.

Publication: Research - peer-reviewJournal article – Annual report year: 2017

Electronic tags are significantly improving our understanding of aquatic animal behavior and are emerging as key sources of information for
conservation and management practices. Future aquatic integrative biology and ecology studies will increasingly rely on data from electronic
tagging. Continued advances in tracking hardware and software are needed to provide the knowledge required by managers and policymakers
to address the challenges posed by the world’s changing aquatic ecosystems. We foresee multiplatform tracking systems for simultaneously
monitoring the position, activity, and physiology of animals and the environment through which they are moving. Improved data collection will
be accompanied by greater data accessibility and analytical tools for processing data, enabled by new infrastructure and cyberinfrastructure. To
operationalize advances and facilitate integration into policy, there must be parallel developments in the accessibility of education and training,
as well as solutions to key governance and legal issues
Original languageEnglish
JournalBioScience
ISSN0006-3568
DOIs
StateE-pub ahead of print - 2017

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Lessons from the first generation of marine ecological forecast products

Year: 2017

Lessons from the first generation of marine ecological forecast products

Payne, M., Hobday, A. J., MacKenzie, B., Tommasi, D., Dempsey, D. P., Fässler, S. M. M., Haynie, A. C., Ji, R., Liu, G., Lynch, P. D., Matei, D., Miesner, A. K., Mills, K. E., Strand, K. O. & Villarino, E. 2017 In : Frontiers in Marine Science.

Publication: Research - peer-reviewJournal article – Annual report year: 2017

Original languageEnglish
JournalFrontiers in Marine Science
DOIs
StatePublished - 2017

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Shifts in coastal sediment oxygenation cause pronounced changes in microbial community composition and associated metabolism

Year: 2017

Shifts in coastal sediment oxygenation cause pronounced changes in microbial community composition and associated metabolism

Broman, E., Sjöstedt, J., Pinhassi, J. & Dopson, M. 2017 In : Microbiome. 5, 1, p. 96 1 p.

Publication: Research - peer-reviewJournal article – Annual report year: 2017

A key characteristic of eutrophication in coastal seas is the expansion of hypoxic bottom waters, often referred to as 'dead zones'. One proposed remediation strategy for coastal dead zones in the Baltic Sea is to mix the water column using pump stations, circulating oxygenated water to the sea bottom. Although microbial metabolism in the sediment surface is recognized as key in regulating bulk chemical fluxes, it remains unknown how the microbial community and its metabolic processes are influenced by shifts in oxygen availability. Here, coastal Baltic Sea sediments sampled from oxic and anoxic sites, plus an intermediate area subjected to episodic oxygenation, were experimentally exposed to oxygen shifts. Chemical, 16S rRNA gene, metagenomic, and metatranscriptomic analyses were conducted to investigate changes in chemistry fluxes, microbial community structure, and metabolic functions in the sediment surface. Compared to anoxic controls, oxygenation of anoxic sediment resulted in a proliferation of bacterial populations in the facultative anaerobic genus Sulfurovum that are capable of oxidizing toxic sulfide. Furthermore, the oxygenated sediment had higher amounts of RNA transcripts annotated as sqr, fccB, and dsrA involved in sulfide oxidation. In addition, the importance of cryptic sulfur cycling was highlighted by the oxidative genes listed above as well as dsvA, ttrB, dmsA, and ddhAB that encode reductive processes being identified in anoxic and intermediate sediments turned oxic. In particular, the intermediate site sediments responded differently upon oxygenation compared to the anoxic and oxic site sediments. This included a microbial community composition with more habitat generalists, lower amounts of RNA transcripts attributed to methane oxidation, and a reduced rate of organic matter degradation. These novel data emphasize that genetic expression analyses has the power to identify key molecular mechanisms that regulate microbial community responses upon oxygenation of dead zones. Moreover, these results highlight that microbial responses, and therefore ultimately remediation efforts, depend largely on the oxygenation history of sites. Furthermore, it was shown that re-oxygenation efforts to remediate dead zones could ultimately be facilitated by in situ microbial molecular mechanisms involved in removal of toxic H2S and the potent greenhouse gas methane.
Original languageEnglish
JournalMicrobiome
Volume5
Issue number1
Pages (from-to)96
Number of pages1
ISSN2049-2618
DOIs
StatePublished - 2017