From ions to ecosystems

From Ions to Ecosystems: A Novel Framework for the Biomonitoring and Management of Vulnerable and Commercial Fishes (UKRI Future Leaders Fellowship 2022-2025)

Overview: This global programme involves a series of case studies that integrate emerging technologies (e.g. electronic archival tags and machine learning), novel chemical tracers and modelling to quantify and predict the movements and fitness of key fish species over a broad range of global change scenarios. We are using the North Sea as a model system to explore how integrated fish health and connectivity monitoring could enhance marine spatial planning. By pairing otolith chemistry and archival tag data from the same fish, we will determine optimal methods for reconstructing individual movement patterns using otolith tracers. To shed light on the mechanisms driving interannual variability in fisheries performance, we will develop and validate new tools for reconstructing fish health and contaminant exposure history. To reveal the critical habitats, dietary sources and fine-scale movement patterns of vulnerable salmonids we will use isotopic maps ('isoscapes') and tracers combined with novel machine learning methods. Finally, to quantify the latent and cumulative effects of hypoxia on fish size and fitness we will combine archival tag records and chemical tracers, then predict the impact of this growing environmental issue on fisheries productivity and stability. The overall synthesis of these case studies will provide new insights into fish habitat needs and their vulnerabilities to interacting stressors, improving our ability to predict fishery responses to differing global change and management scenarios. Finally, to promote multidisciplinary innovation and the integration of these emerging tools into mainstream resource management, we will establish an International Consortium dedicated to the EXploration, TRanslation and Application of Chemical records in fish Tissues (EXTRACT).

A series of case studies will be used to show case how emerging technologies can reveal fish-environment interactions and quantify individual, population and fisheries responses to different stressors.

Work Package 1: Fish Connectivity in a Crowded Ocean

1. How can we better quantify contribution rates of estuarine nursery grounds to the adult stock?

Model species: European seabass. Study leads: Anna Sturrock, Michelle Taylor, Tom Cameron (all Uni of Essex)

Model species: Dover sole. Study leads: Marion Lefebvre du Prey (PhD student at the University of Plymouth), Ben Ciotti, (Uni of Plymouth) Anna Sturrock.

2. How do environmental conditions influence settlement timing, growth rate and success?

Model species: European seabass. Study leads: Joe Dawson (Research Assistant at the Uni of Essex), Anna Sturrock, Kieran Hyder (Cefas), Rachel Turnball, Ben Ciotti (Uni of Plymouth), Filipe Martinho (Uni of Coimbra).

3. Do eye lenses reliably record contaminant exposure histories? If so how does early life exposure influence fitness and connectivity?

Model species: European eel, dab, Atlantic salmon, European seabass. Study leads: Rebekah Boreham (postdoctoral researcher at Uni of Essex), Sara Leston (Uni of Coimbra), Philip White (ATU), Clive Trueman (Uni of Southampton)

4. Validating the use of otolith chemistry and chemoscapes to reconstruct seasonal movements of adult marine fish using paired data storage tag records.

Model species: North Sea plaice, European seabass. Study leads: Anna Sturrock, Serena Wright (Cefas), Ewan Hunter (AFBI).

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Work Package 2: Global Threats to Diadromous Fishes

1. Using chemical tools to reconstruct salmon habitat use across populations, years and species

Can isotopic tools and automated machine learning methods be used to improve dam operations and watershed management in the face of increasing climate variabilty?

Model species: Chinook salmon. Study leads: Anna Sturrock, Rachel Johnson (NOAA), Malte Willmes (NINA), Kohma Arai (UC Davis), Carson Jeffres (UC Davis)

Integrating eye lens and otolith chemical markers and genetics to identify the river of origin of genetically-overlapping populations of Atlantic salmon and infer population-specific impacts of offshore windfarms

Model species: Atlantic salmon. Study leads: Mike Bevins Cameron (PhD student at the Uni of Essex), Anna Sturrock, Matt Newton (MSS), Colin Bull (Uni of Sturling), Eoin O'Gorman (Uni of Essex).

Using otolith oxygen isotopes to track salmon movements at sea. Does pathways vary among years and populations?

Model species: Atlantic salmon. Study leads: Lucy Smith (PhD student at the Uni of Essex), Anna Sturrock, Nora Hanson (MSS), Colin Bull (Uni of Sturling), Eoin O'Gorman (Uni of Essex).

Using a paired eyes and ears approach to reconstruct freshwater and marine habitat use of Norwegian trout and the links between growth and migratory phenotype

Model species: Brown trout. Study leads: Peter Betts (PhD student at the Uni of Essex), Anna Sturrock, Rachel Paterson (NINA), Tor Næsje (NINA), Eoin O'Gorman (Uni of Essex), Astrid Tonstad (NINA).

2. Factors driving selective mortality

Does size at outmigration influence at-sea survival, and does marine size-selective mortality rates vary among latitudes, years and populations?

Model species: Atlantic salmon. Study leads: Lucy Smith (PhD student at the Uni of Essex), Anna Sturrock, Nora Hanson (MSS), Colin Bull (Uni of Sturling), Eoin O'Gorman (Uni of Essex).

What are the factors driving vaterite formation in salmon otoliths and is there a long term survival impact?

Model species: Chinook salmon. Study leads: Lucy Smith (PhD student at the Uni of Essex), Anna Sturrock, Rachel Johnson (NOAA), Malte Willmes (NINA).

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Work Package 3: Lifetime effects of hypoxia on fish health

1. Validating hypoxia exposure markers in archival tissues

Can we improve the reliability and predictive power of the otolith manganese hypoxia marker (and eye lens sulphur isotope marker) by understanding the relationships between sediment, water, blood and otolith concentrations?

Model species: Baltic cod, Baltic Flounder, Round Goby. Study leads: Alexia Dubuc (Postdoctoral researcher at Uni of Essex), Anna Sturrock, Karin Hüssy (DTU), Stefanie Haase (Thünen Institute), Karin Limburg (SUNY ESF), Ben Walther (Texas A&M University - Corpus Christi).

Can we use otolith Mn to identify periods of low DO in data storage tagged cod with "known" migration histories?

Model species: Baltic cod. Study leads: Alexia Dubuc (Postdoctoral researcher at Uni of Essex), Anna Sturrock, Karin Hüssy (DTU), Stefanie Haase (Thünen Institute), Karin Limburg (SUNY ESF), Ben Walther (Texas A&M University - Corpus Christi).

2. Legacy and fishery effects of lifetime hypoxia exposure

Does early life hypoxia exposure (inferred by otolith Mn) lead to reduced adult size and/or fecundity? If so, what are the global effects on fisheries biomass?