PhD defence on resilience and stability of marine fish communities – Unravelling the role of biodiversity

Marine ecosystems are under pressure. This is primarily because of human activities such as overfishing, habitat destruction, pollution and climate change. These pressures are causing changes in species occurrence and abundance and are threatening valuable species with extinction.

Marine biodiversity has an intrinsic value by itself, but the loss of biodiversity is also affecting the overall structure and functioning of ecosystems, as well as the provisioning of services for human wellbeing. Ultimately, preserving the structure and functioning of marine ecosystems has become a primary management objective. However, the current knowledge of the underlying processes promoting resilience and stability of marine communities is scarce. Consequently, there is an urgent need to identify the key drivers of ecosystem resilience and stability in complex natural ecosystems.

In her PhD thesis “Resilience and vulnerability of marine fish communities to change”, Louise C. Flensborg from DTU Aqua describes how she has used large-scale data on bottom-living fish species in combination with species key characteristics, i.e., traits, to estimate indicators of resilience. These indicators reflect key elements of important biodiversity structures and can help to characterize and monitor resilience in natural ecosystems. Furthermore, she has explored how these indicators are related to overall ecosystem stability and environmental conditions, and she has investigated how stability in natural ecosystems varies across scales. This provides a much-needed framework to characterize and quantify key indicators of resilience in a large-scale marine ecosystem.

Louise C. Flensborg concludes that it’s important to use multiple indicators, an appropriate scale and system-specific analysis when assessing resilience in natural marine ecosystems. Furthermore, she states that the inclusion of resilience indicators into management actions can help the preservation of marine biodiversity.

About the PhD defence

Louise C. Flensborg will defend her PhD thesis "Resilience and vulnerability of marine fish communities to change” on Friday 15 September 2023, 12:00 on Zoom and at DTU, Building 341, Auditorium 22, 2800 Kgs. Lyngby. 

Supervisors

• Principal supervisor: Senior Researcher Martin Lindegren, DTU Aqua
• Co-supervisor: Professor David N. Bravo, Globe Institute, University of Copenhagen

Examiners

• Senior Researcher Cornelia Jaspers, DTU Aqua (chair)
• Research Scientist Manuel Hidalgo, Spanish Institute of Oceanography, Spain
• Researcher Susa Niiranen, Stockholm Resilience Centre, Sweden

Chairperson at defence

• Senior Researcher Tommy Norin, DTU Aqua

Learn more

A copy of the thesis is available by e-mail on request. Please contact Louise C. Flensborg, loufl@aqua.dtu.dk