Citizen science is increasingly used to include in ecological monitoring over the past three decades. Web-based applications or smart phones enable citizens to record observations or experiences at larger temporal and spatial scale and provide opportunities for a larger number of citizens to participate in mapping observations. Citizen science can also be used to record, or map observed and experienced ...

Vertical behavior, such as diel vertical migration (DVM) and swarming are widespread among zooplankton. At higher latitudes, synchronized DVM is mostly absent during summer and predominantly herbivorous copepods tend to form large near-surface swarms. This behavior is risky because it can make them vulnerable to visual predators. Here, we used ca. 12 days of mid-summer (28 June to 10 July 2018) ...

Assessing the role of weather in the dynamics of wildlife populations is a pressing task in the face of rapid environmental change. Rodents and ruminants are abundant herbivore species in most Arctic ecosystems, many of which are experiencing particularly rapid climate change. Their different life-history characteristics, with the exception of their trophic position, suggest that they should show ...

Feeding studies give an indication about the role and position of species within ecosystems and provide crucial knowledge for management. Traditional methods are based on morphological identification of prey. DNA metabarcoding is a promising tool that allow for identification of specific prey items, also when highly digested. A total of 63 stomachs from three skate species caught in the Barents Sea ...

Mitochondrial DNA (mtDNA) has been extensively used to explore phylogenetics since the its use became available. This science is considered useful in discerning relationships and evolutionary histories that are not possible with morphological studies alone. The sleeper sharks (genus: Somniosus) are a group of poorly understood, long-lived, iconic species whose taxonomic status within the genus have ...

Mercury (Hg) is considered as a global threat which is emitted in the environment through natural sources or anthropogenic activities. Emissions of mercury decreased during the last decades because of the implementation of mitigation measures. However, with the ongoing climate change, ecosystems are directly (e.g., rising temperature) or indirectly impacted (i.e., altered ecosystem by e.g., invasive ...

Populations living close together in space are likely to experience more similar environmental fluctuations, and thus may display similar temporal changes in population parameters, in other words synchrony. Interspecific synchrony has implications for ecosystem stability, and highly synchronous populations and communities tend to have a higher risk of extinction. In this thesis, I used long-term ...

The Arctic Ocean is overwhelmingly forced by its lateral boundaries, and interacts with, the global system. For the development of nested conceptual models of the Arctic Ocean ecosystem we here choose the full pan-Arctic as our focal scale. Understanding the pan-Arctic scale, however, requires that we look at the underlying scales of its major components, by considering regionality, connectivity and ...

Marine ecosystems, and particularly fjords, are experiencing an increasing level of human activity on a yearround basis, including the poorly studied winter period. To improve the knowledge base for environmentally sustainable management in all seasons, this study provides hydrographic and biological baseline data for the sub-Arctic fjord Kaldfjorden, Northern Norway (69.7 N, 18.7 E), between ...

Thyroid hormone (TH) and estradiol (E2) direct seasonal switches in ovine reproductive physiology. In sheep, as in other mammals and birds, control of thyrotropin (TSH) production by the pars tuberalis (PT) links photoperiod responsiveness to seasonal breeding. PT-derived TSH governs opposite seasonal patterns of the TH deiodinases Dio2/Dio3 expression in tanycytes of the neighboring medio-basal ...