Nettsider med emneord «Marine ecology»
Almost two decades of scientific monitoring of European lobster (Homarus gammarus) in Skagerrak confirm that Marine Protected Areas (MPAs) benefit the species’ local survival, but reveal geographic differences in lobster abundance that indicate not all MPAs are equal at reaching conservation goals.
A new pan-arctic study indicates that Calanus copepods do not necessarily descend deep for diapause in winter; instead, parts of the population remain active. Moreover, the deeper distribution of the larger and more conspicuous Calanus hyperboreus indicates that predation pressure is a key trigger for diapause at depth. In the central Arctic Ocean where visual predation pressure is lower, copepods might be relieved from the incentive to descend and can remain closer to the surface in winter.
The extensive spawning migration of Northeast Arctic cod was suggested to be counterbalanced by increased early-offspring survival, however we find in a study published in July in Marine Ecology Progress Series, that early offspring growth should be considered as another factor explaining this long-distance migration.
Ecology, population dynamics, genomics and bioeconomics of marine fish stocks
Opening the sea areas around Lofoten and Vesterålen islands for petroleum activities is a highly debated topic. One of the main concerns has been to what extent an accidental oil-spill may affect the ecologically and economically important species of fish that spawn in the area. We have investigate how an increased mortality event at the egg and larval stage in cod may affect the population.
Extreme events in the marine environment, like marine heatwaves, are likely at least as important as changes in mean values for causing threats to biodiversity, with impacts on ecosystem services and consequences for human systems. The potential of human and natural systems to adapt to such changes remains unclear, but two recent articles in the high-impact journal PNAS look closer at the possibilities.