Search results for "VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Zoogeografi: 486"
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Demographic history has shaped the strongly differentiated corkwing wrasse populations in Northern Europe
2019
Understanding the biological processes involved in genetic differentiation and divergence between populations within species is a pivotal aim in evolutionary biology. One particular phenomenon that requires clarification is the maintenance of genetic barriers despite the high potential for gene flow in the marine environment. Such patterns have been attributed to limited dispersal or local adaptation, and to a lesser extent to the demographic history of the species. The corkwing wrasse (Symphodus melops) is an example of a marine fish species where regions of particular strong divergence are observed. One such genetic break occurred at a surprisingly small spatial scale (FST ~0.1), over a s…
Methods for studying coastal bivalves in a changing world : A review and implications for management
2021
Master's thesis in Coastal ecology (BIO501) Anthropogenic activities such as pollution, CO2 emission, and overfishing, are among leading reasons for global environmental change and negative impacts on the marine environment including loss of biodiversity. Marine bivalves are an example of species that suffers from such consequences while they have high value in both aquaculture and marine ecosystems. With the existence of many threats including overharvesting, invasive species, parasites, and diseases, coastal bivalves such as flat oysters (Ostrea edulis) and blue mussels (Mytilus spp) are in many places endangered. The existing knowledge gaps in the historic and current distribution, howev…
Do cold-water corals spatially correlate with submarine canyons in the Bay of Biscay? : A GIS study analysing the spatial distribution of cold-water …
2020
Master's thesis in Coastal ecology (BIO501) The seascape of the Bay of Biscay is a mysterious place. It is located to the west of France and the north of Spainand is often defined as well-differentiated geomorphological unit. The continental margin of the BoB is incised with many submarine canyons and is also thought to be a hotspot for cold-water corals.Unfortunately, it is an area under high anthropogenic pressure where intense fishing activity, bottom trawling especially, is causing major disturbances to benthic habitats such as cold-water corals. Cold-water corals have been well studied along the European margin and have more frequently been recorded in the northeastAtlantic than any ot…
Mapping the invasion: spatiotemporal distribution of the Pacific oyster in Scandinavia
2021
Master's thesis in Coastal ecology (BIO501) The Pacific oyster (Magallana/Crassostrea gigas) is an invasive species to Scandinavia, originating on the Pacific coasts of Asia. Introduction to Europe of these oysters was a result of farming initiatives, put in place following declines of the native oyster species (Ostrea edulis). The oysters were introduced to Denmark, Sweden, and Norway in farming trials during the 1970s, however Norwegian and Swedish populations have also been a consequence of larval drift. They are not currently commercially farmed in any of the three countries due to the effects that wild populations have on the areas they invade. To map historical and present distributio…