There is a pressing need to better understand movement patterns and complex life histories of migratory sharks to aid conservation efforts. With important ecosystem-wide effects which cascade down trophic levels the life-history characteristics of sharks (late maturity, slow growth, increased longevities, low reproductive output) leave them vulnerable to human exploitation and environmental change. Quantifying resilience to these changes allows us to predict a species´ future response. Information on the routine distribution of such keystone species across habitats during time and space at different stages of their life-histories is unknown, despite advances in tagging technology. To resolve this knowledge gap, this project aims to reconstruct the environmental histories, feeding and movement patterns of the migratory spurdog shark (Squalus acanthias) by utilizing natural biochemical ‘tags’ (stable isotopes, trace elements) as environmental/trophic proxies1. Currently classed as vulnerable worldwide but endangered in the North-East Atlantic, it was prohibited to commercially fish spurdog in EU and UK waters but in October 2022 ICES revised this, advising reopening the fishery. Spurdog are an aggregating species, gathering in huge numbers, therefore, understanding the basis of these gatherings, their composition, and relevance to this species' marine functional connectivity is both timely and crucial to their conservation management.
Cartilage growth rings act as environmental fingerprints and will be analyzed using laser ablation to investigate shifts in habitat use and migration during the lifetimes of individuals. To complement this analysis, the student will use an environmental genomics approach3 to better understand how the genomic characteristics of individuals adapt them to the environmental conditions they experience during their lifetime. Our annotated spurdog genome will allow identification and potential function of genes identified by this approach. Understanding the genetic basis of adaptation in spurdog is critical as their aggregations contain closely related individuals2 and loss of kin groups can rapidly erode genetic diversity of stocks, increasing their vulnerability to climate change. Additional elasmobranchs (white sharks, thornback rays) can be similarly studied, allowing comparison of lifestyles contrasting with spurdog to identify generalizations of ecological life-history reconstructions with genomic markers associated with life-history traits.
Key questions could include: What does the time series of environmental proxies tell us about the habitat(s), locations, migrations, and trophic level(s) an individual experienced during its lifetime? Do estimates of field metabolic rate vary during an individual´s lifetime, with habitat/trophic level, within/between kin aggregations? What associations are there between environmental proxies and genomic data, and how much variation is there within/between recognized aggregations/populations? How do these estimates vary between species, and what ecological/phylogenetic explanations might account for these observations?
This project provides training in core and generic skills, with cutting edge technologies (population genomics, bioinformatics, stable isotopes, multi-elemental fingerprinting) integrating Biodiversity and Earth Systems to translate findings into improved policy and practice for effective conservation management of endangered marine species.
Candidate Background: The successful candidate should have an interest in ‘biochemical tags’ using analytical chemistry (stable isotopes) and their application to conservation biology; and an interest in genetics/genomics approaches to conservation as well as experience in data handling/statistics. Experience in bioinformatics and population genomics/genetics and/or analytical chemistry and use of stable isotopes is desirable.
More project details are available here: https://www.quadrat.ac.uk/quadrat-projects/
How to apply: https://www.quadrat.ac.uk/how-to-apply/