Patchy zooplankton grazing and high energy conversion efficiency: Ecological implications of sandeel behavior and strategy

Sandeel display strong site-fidelity, and spend most of their life buried in the seabed. This strategy carries important ecological implications. Sandeels save energy when they are not foraging but in return are unable to move substantially and therefore possibly are sensitive to local depletion of prey. Here we studied zooplankton consumption and energy conversion efficiency of lesser sandeel (Ammodytes marinus) in the central North Sea, using stomach data, length and weight-at-age data, bioenergetics, and hydrodynamic modeling. The results suggested: (i) lesser sandeel in the Dogger area depend largely on relatively large copepods in early spring. (ii) lesser sandeel is an efficient converter making secondary production into fish tissue available for higher trophic levels. Hence, changes in species composition towards a more herring dominated system, as seen in recent times, may lead to a decrease in system transfer efficiency. (iii) sandeels leave footprints in the standing copepod biomass as far as 100 km from the edge of their habitat, but smaller and more isolated sandeel habitat patches have a much lower impact than larger patches, suggesting that smaller habitats can sustain higher sandeel densities and growth rates per area than larger habitats

Kirkegårdens leder: Anmeldelse af jubilæumsbog for Foreningen af Danske Kirkegårdsledere

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Løsøreerververs kreditorvern i tilfeller av "sale- and leaseback". Hvordan oppnår løsøreerverver vern mot etterfølgende kreditorbeslag, og i hvilken grad ivaretas hensynet til notoritet?

Masteroppgavens overordnede tema er løsøreerververs kreditorvern i tilfeller av «sale- and leaseback». Det har i lang tid vært uklart om det oppstilles et krav om at avhenderen må fratas besittelsen over løsøregjenstanden, for at en løsøreerverver skal oppnå vern mot etterfølgende kreditorbeslag. I HR-2021-2248-A (Aurstad maskinutleie) ble rettstilstanden delvis oppklart, ved at Høyesterett la til grunn at kravet om besittelsesfratakelse er gjeldende rett. For avtaler om «sale- and leaseback», hvor forutsetningen er at avhenderen skal fortsette å ha løsøregjenstanden i sin besittelse, er det fremdeles uklart hvordan den aktuelle rettsvernsakten gjennomføres. Oppgaven består av en rettsdogmatisk analyse av hvordan rettsvern oppnås i tilfeller av «sale- and leaseback», og om dette ivaretar det sentrale hensynet til notoritet.MasteroppgaveJUS399MAJUR-2MAJU

Evaluating dispersal potential of an invasive fish by the use of aerobic scope and osmoregulation capacity

Non-indigenous species (NIS) can impact marine biodiversity and ecosystem structure and function. Once introduced into a new region, secondary dispersal is limited by the physiology of the organism in relation to the ambient environment and by complex interactions between a suite of ecological factors such as presence of predators, competitors, and parasites. Early prediction of dispersal potential and future 'area of impact' is challenging, but also a great asset in taking appropriate management actions. Aerobic scope (AS) in fish has been linked to various fitness-related parameters, and may be valuable in determining dispersal potential of aquatic invasive species in novel environments. Round goby, Neogobius melanostomus, one of the most wide-ranging invasive fish species in Europe and North America, currently thrives in brackish and fresh water, but its ability to survive in high salinity waters is unknown to date. We show that AS in round goby is reduced by 30% and blood plasma osmolality increased (indicating reduced capacity for osmoregulation) at salinities approaching oceanic conditions, following slow ramping (5 PSU per week) and subsequent long-term acclimation to salinities ranging between 0 and 30 PSU (8 days at final treatment salinities before blood plasma osmolality measurements, 12-20 additional days before respirometry). Survival was also reduced at the highest salinities yet a significant proportion (61%) of the fish survived at 30 PSU. Reduced physiological performance at the highest salinities may affect growth and competitive ability under oceanic conditions, but to what extent reduced AS and osmoregulatory capacity will slow the current 30 km year-1 rate of advance of the species through the steep salinity gradient from the brackish Baltic Sea and into the oceanic North Sea remains speculative. An unintended natural experiment is in progress to test whether the rate of advance slows down. At the current rate of advance the species will reach the oceanic North Sea by 2018/2019, therefore time for taking preventative action is short