MSc in Marine Physics Eva Chamorro Garrido at the Department of Arctic and Marine Biology (AMB) will Thursday 26 March 2026 hold her trial lecture and defend her thesis for the PhD degree in Natural Science.
Trial lecture on assigned topic will take place at 12.15: "The importance of Calanus species in the North Atlantic and their relevance for commercial harvesting and fisheries"
Later, at 14.15 she will defend her thesis entitled: "From the Atlantic Basin to the Norwegian Shelf: High resolution spatial-temporal variability of copepods and their relationship with environmental variables, with a focus on Calanus finmarchicus"
Head of department at AMB Hanne Risan Johnsen will lead the disputation.
Popular Science Summary
Zooplankton are drifting animals that play a crucial role in ocean ecosystems. They form the link between phytoplankton and larger animals such as fish, seabirds, and whales. One of the most important zooplankton species in the North Atlantic is Calanus finmarchicus, a small copepod that stores large fat reserves, making it a crucial food source for many marine species. This PhD focuses on understanding how environmental conditions shape the distribution of this key species in the North Atlantic, with particular emphasis on the Lofoten Basin.
To address this question, the study combined environmental data on wind, ocean currents, temperature, salinity, and food availability derived from Chlorophyll-a in the ocean. In addition, zooplankton were collected using nets and optical instruments to measure how many individuals were present and how they were distributed at different depths. These data were analysed using statistical models to better understand how environmental factors influence the distribution of C. finmarchicus. Numerical ocean–ecosystem models were also used to simulate C. finmarchicus abundances and to understand how patches form and what environmental factors shape their presence.
The results show that the vertical position of C. finmarchicus changes with season and life stage and is mainly influenced by temperature and Chlorophyll-a. High food availability in the surface was associated with shallower distributions, while temperature affected depth preferences across the species’ range. In addition to these vertical patterns, we found that patchiness in the Lofoten Basin closely followed Chlorophyll-a distributions shaped by ocean circulation. Finally, we found that wind mainly affected copepods positioned near the surface, carrying them across the shelf. However, larger copepods could swim actively and avoid being transported. Overall, this thesis improves our understanding of the processes that control copepods distribution and patchiness, which is essential for predicting how marine ecosystems may respond to future climate-driven changes.
Evaluation Committee
Supervisors
Streaming
Both the trial lecture and defense and will be streamed and recorded:
Thesis
The thesis is available in Vitenarkivet