PhD defence and trial lecture: Aurelien Delaval (FBA)

Doctoral candidate Aurelien Delaval will hold a trial lecture and defend his thesis for the degree Philosophiae Doctor (PhD) at the Faculty of Biosciences and Aquaculture (Bodø), Nord University.

Start date:

14 December 2021 10:15

End date:

14 December 2021 15:00

Location:

A5 Petter Thomassen
​​​​​​​​​Photo.JPG​​PhD candidate:​ Aurelien Delaval

Trial lecture topic

tba​

Thesis title

Population genomics of a critically endangered data-deficient elasmobranch, the blue skate Dipturus batis

Evaluation Committee

​​​- Research Scientist Sophie Arnaud-Haond, Laboratoire Halieutique Mediterranee, France
- Principal Scientist​ Andrew Gill, Centre for Environment, Fisheries and Aquaculture Science, UK​
- Professor Truls Moum, FBA, Nord University​

Supervisory Committee

- Professor Leslie Noble, FBA, Nord University
- Professor Galice Hoarau, FBA, Nord University​t
- Professor Catherine Jones, University of Aberdeen, UK
- Group Leader ​Peter John Wright, ​Ecology and Conservation, Marine Scotland Science, ​UK​
- Research Fellow James Thorburn, School of Biology, University of St. Andrews, UK​

About the thesis

Many elasmobranch species have experienced pronounced population declines during the last century, representing an important conservation and socioeconomic issue. Instituting appropriate conservation measures for elasmobranchs relies on a thorough understanding of their contemporary population structure, the identification of important habitat areas, and estimates of demographic parameters such as population size. Unfortunately, conservation efforts have been hindered by a lack of biological knowledge stemming from issues such as taxonomic confusion, misreporting of catches, and methodological constraints. Population genomic approaches are among the novel research methodologies that can help fill important knowledge gaps for data-deficient and critically endangered elasmobranchs.

In this thesis, we used population genomic approaches to address knowledge gaps relevant to the conservation of the Critically Endangered blue skate (Dipturus batis), one of Europe's largest benthic elasmobranchs. First, we sequenced the full mitochondrial genome of D. batis, a resource that will facilitate species identification and help resolve taxonomic uncertainties among hardnosed skates (Family Rajidae). Second, we used a genome-wide genotyping approach to assess the population structure of D. batis, estimate effective population sizes, and investigate patterns of selection along environmental gradients. Lastly, we evaluated the suitability of a novel demographic modelling approach (close-kin mark-recapture) as a monitoring tool for the Celtic Sea population of D. batis, and produced the first absolute abundance estimate for the species. In doing so, we also identified a potential area of critical habitat based on the spatio-temporal distribution of close relatives. Overall, this thesis revealed important biological patterns for D. batis that will have direct implications for its conservation, and demonstrates the value of genomic approaches in elasmobranch conservation research.​

Trial lecture: 10:15 - 11:05
PhD defence​​: 12:15 - 15:00


Start date:

14 December 2021 10:15

End date:

14 December 2021 15:00

Location:

A5 Petter Thomassen
The PhD trial lecture and defence are open to the public. The thesis is available upon request. Please contact Jeanett Stegen.