ESSAS 2026

Abstract Booklet

Monday 22 June

• 17:00–21:00 Icebreaker & informal gathering

Tuesday 23 June

• 09:00–09:15 Welcome

Session 3

• 09:15–09:45 Keynote: Steven Campana
  Cod dynamics and the changing roles of humans and the environment over 1100 years of fishing
• 09:45–10:00 Anders Frugård Opdal
  Phenotypic plasticity in Atlantic cod spawning phenology can mitigate trophic mismatch under ocean warming
• 10:00–10:15 William Butler
  A haul-level Bayesian state-space model for estimating juvenile cod abundance and mortality from survey data
• 10:15–10:30 Ingibjörg G. Jónsdóttir
  Juvenile gadid dynamics in northwest Icelandic fjords
• 10:30–11:00 Coffee Break
• 11:00–11:15 Anja K. Nickel
  Thermal niche partitioning in juvenile gadoid nurseries - an acoustic telemetry study in a sub-Arctic fjord
• 11:15–11:30 Guðbjörg Ásta Ólafsdóttir
  Divergent thermal modulation of juvenile cod and saithe in subarctic nearshore nurseries
• 11:30–11:45 Hanna Rudnick
  Cod Chronicles: Unravelling environmental effects on growth and condition of western Baltic cod based on otolith microchemistry
• 11:45–12:00 Ingrid Spies
  Newly discovered Pacific cod ecotypes with distinctive life histories provide a portfolio effect for a commercially important Alaska groundfish
• 12:00–12:15 Michelle Valliant
  Distribution, movement, and behavior of inshore and offshore juvenile Atlantic cod in nearshore waters
• 12:15–13:45 Lunch
• 13:45–14:00 Micah Reismann
  Embryonic Bottlenecks: Linking Antioxidative Defense and Oxidative Damage to Temperature-Driven Mortality in Polar Cod
• 14:00–14:15 Daniela Storch
  Ocean warming affects gonadal maturation of female polar cod
• 14:15–14:30 Myrthe Berber Bergsma
  Arctic cod morphometrics as an energy and health indicator along a 3400 km latitudinal gradient in the Canadian Arctic
• 14:30–14:45 Pamela J. Woods
  Spatial variation in Icelandic cod growth and condition
• 14:45–15:00 Robynne C. Nowicki
  Seasonal and size-dependent energy shifts in polar cod and capelin
• 15:00–15:30 Coffee Break
• 15:30–15:45 Stina Kolodzey
  Does maternal size structure affect larval viability in Atlantic cod (Gadus morhua)?
• 15:45-16:00 Sofia Amieva Mau
  Menu changes - Are barnacle nauplii a suitable prey for cod larvae (Gadus morhua)?
• 16:00–16:15 Akihide Kasai
  Habitat Segregation of key gadid fishes in the Pacific Arctic region revealed by environmental DNA
• 16:15-16:45 Poster lightning talks
• 16:45-18:00 Posters & refreshments

Wednesday 24 June

Session 2

• 09:00–09:30 Keynote: Kaitlyn O'Brien
  Spatiotemporal Quantification of Bering Sea Borealization
• 09:30–09:45 Franz Mueter
  Borealization hot spots of the Bering Sea groundfish community
• 09:45–10:00 Raul Primicerio
  Borealization triggers reorganization of Arctic coastal and shelf ecosystems
• 10:00–10:15 Emma Schena
  Trophodynamic indicators to map changes in a Subarctic ecosystem
• 10:15–10:30 Francesco Golin
  Sensitivity of Icelandic groundfish communities to climate change and fishing
• 10:30–11:00 Coffee Break
• 11:00–11:15 Kate Stafford
  Shifting northwards: changing phenologies of subarctic and Arctic marine mammals
• 11:15–11:30 Shannon E. Moore
  Predicting shifts in demersal fish distributions and functional diversity across the Barents Sea
• 11:30–11:45 Matthew Robertson
  Hungry like the fish
• 11:45–12:00 Martin W. Miles
  The Early 20th Century Warming of the 1920s–1930s around Greenland
• 12:00–12:15 Astrid E.J. Ogilvie
  Warm Times, Cold Times: Variations in the Past Climate of Iceland
• 12:15–13:45 Lunch

Session 1

• 13:45-14:15 Keynote: Beatriz S. Dias
  Exploring the impacts of marine heatwaves in the Gulf of Alaska through an ecosystemic perspective
• 14:15–14:30 Angel Ruiz-Angulo
  Assessment of Marine Heat Wave Detection and Prediction in Icelandic Waters
• 14:30-14:45 Hreiðar Þór Valtýsson
  Are subarctic nations’ fisheries benefiting from climate change?
• 14:45–15:00 Marianne Williams-Kerslake
  Lower-Trophic-Level Responses to Marine Heatwaves in the Nordic Seas
• 15:00–15:30 Coffee Break
• 15:30-15:45 Russell R Hopcroft
  Twenty-five years of heatwaves in the northern Gulf of Alaska
• 15:45-16:00 Szymon Surma
  Projecting marine heatwave impacts on Norwegian spring-spawning herring
• 16:00–16:15 Iman Rousta
  The North Atlantic Heat Engine
• 18:00 Buses to conference dinner

Thursday 25 June

Session 4

• 09:00–09:15 Björn Birnir
  The Mean Depth Difference and Ocean Currents in the Subarctic Seas
• 09:15–09:30 Bylgja Sif Jónsdóttir
  Drivers of Biodiversity Patterns in Deep-Sea Benthic Communities
• 09:30–09:45 David Cote
  Physical Boundaries, Connectivity, and Functional Group Resilience
• 09:45–10:00 Yu Makino
  Observation technique of suspended and settling particles with an Event-based Vision Sensor
• 10:00–10:15 Filipa I. P. Samarra
  Shifting interactions between marine mammals
• 10:15–10:30 Paul J. Wensveen
  The importance of the Nordic Seas to a deep-diving cetacean
• 10:30–11:00 Coffee Break
• 11:00–11:15 Hildur Pétursdóttir
  Diet composition and feeding behavior of capelin
• 11:15–11:30 Katrine Wilhelmsen Melaa
  Investigating coexistence of Sebastes mentella and S. norvegicus
• 11:30–11:45 Elvar Hallfredsson
  Deep-sea fish communities at the eastern slope of the Norwegian Sea – spatial and temporal gradients and vulnerability to climate change.
• 11:45–12:00 Warsha Singh
  Integrated Ecosystem Assessment to support sustainable management of the Icelandic Waters ecoregion
• 12:00-12:15 Hildur Magnúsdóttir
  Open net-pen aquaculture of Atlantic salmon in an Icelandic threshold fjord
• 12:15–13:45 Lunch

Session 5

• 13:45–14:00 Øystein Varpe
  Ecological consequences of less sea ice and more light
• 14:00–14:15 Erin Kathleen Redmond
  Adapting to a changing Arctic
• 14:15-14:30 Melissa Chierici
  Acidification trends and biological consequences in coastal Arctic
• 14:30–14:45 Emily Donham
  Ocean acidification as a collective action problem
• 14:45–15:00 Samuel P.S. Rastrick
  Ocean acidification may increase the biological impact of legacy metal pollution
• 15:00–15:30 Coffee Break
• 15:30–15:45 Agneta Fransson
  Chemical gradients from fjord to shelf in Arctic fjords
• 15:45–16:00 Natalie Monacci
  Observing the biogeochemistry of Alaska’s subarctic fjords
• 16:00–16:15 Haley Geizer
  Biogeochemical differences in Arctic fjord sediments
• 16:15–16:30 Sonnich Meier
  Persistent organic pollutants, metals, and energy in the Barents Sea food chain
• 16:30–16:45 Michael S. Bank
  Using machine learning and isotope geochemistry to track pollution
• 16:45–17:00 Einar Pétur Jónsson
  Insights from multi-driver experimental research conducted in Iceland
• 17:00–17:15 Conference wrap-up

• Silvana Gonzalez
  The cascading impacts of marine heatwaves on Norwegian coastal ecosystems
• Clarke A Blair
  The effect of temperature on gonad development and reproductive investment in capelin (Mallotus villosus)
• Sara Harðardóttir
  Toxigenic diatoms in Icelandic waters: insights from long-term monitoring and sedimentary ancient DNA
• Todd Sformo
  Monitoring Fishes in Elson Lagoon, Utqiaġvik (Barrow), AK, for evidence of Borealization.
• Robynne C. Nowicki
  Seasonality and water masses shape energetics of polar cod (Boreogadus saida): Quantifying energy density and condition indices
• Sander Digre
  Linking ecosystem variability to individual energy use and growth in Faroe Shelf cod
• Guðbjörg Ásta Ólafsdóttir
  The MOON infrastructure project - Marine Open Observation Network
• Valerie Chosson
  Let the dead tell the story: Marine mammals strandings as evidence of changes in Icelandic Waters.
• Jacob Max Christensen
  Geneflow and genetic structure of a wide-spread Arctic fish, Liparis fabricii
• Eirik Kristoffer Bjøru Hansen
  Diet of deep-sea fish on the Norwegian continental slope
• Andrew Majewski
  Borealization? The stability of demersal offshore fish assemblages in the Canadian Beaufort Sea and Amundsen Gulf
• Ragnar Edvardsson
  Synergies between underwater cultural heritage and biodiversity conservation in Iceland: Insights for achieving 30× 30 targets
• Kolbeinn Hrólfur Sæmundsson
  Variation in diet composition and dietary diversity of 0-group juvenile cod and saithe in nearshore nurseries
• Michelle Valliant
  ICE Fish Research: Science Communication from Iceland

The meeting theme is “Borealization: Subarctic and Arctic Marine Systems in Transition.”
Sessions include:

• Marine Heatwaves: Impacts on High Latitude Ecosystems from Physics to Biology and Human Communities
• Tracking Borealization: Physical Change, Biological Responses, Community Impacts
• Gadids under Borealization: Ecology, Fisheries, and Management
• Connections across the Subarctic Atlantic: Physics to Fish, Fjords to Gyres, Surface to Seafloor
• The Effects of Multiple Drivers on Arctic and Sub-Arctic Coastal/Fjord Environments: Bridging Marine Chemistry and Biology

All sessions are designed to span natural and social sciences and to cover systems from the coast to the deep sea.

1. Marine Heatwaves: Impacts on High Latitude Ecosystems from Physics to Biology and Human Communities
   Co-chairs: Bia Dias, Ben Fitzhugh, Angel Ruiz Angulo
   
   This session invites contributions examining the impacts of marine heatwaves (MHW) on high-latitude systems. We welcome papers that (1) situate marine heatwaves within the broader climate–oceanographic context, including physical mechanisms, cross-system comparisons, food-web restructuring, and ecosystem functioning under sustained heat stress; (2) present species-specific case studies that document ecological, economic, and social impacts of MHWs on important fish or shellfish, their fisheries, and dependent communities in high-latitude systems; and (3) explore adaptations by affected communities and management systems to warming events throughout human history, including strategies that integrate ecological and socioeconomic information to build resilience in rapidly changing oceans.
   
2. Tracking Borealization: Environmental Change, Biological Responses, Community Impacts
   Co-chairs: Franz Mueter, Pavel Emelin, Jacob Kasper
   
   This session will document and quantify observed changes in Subarctic and Arctic marine ecosystems that illuminate the extent of borealization—including evidence that both supports and challenges it. We welcome studies on the direction and pace of change in key oceanographic and biogeochemical properties; shifts in species distributions and community composition from plankton to fishes, seabirds, and marine mammals; and changes in human communities (e.g. harvest patterns, population trends). Contributions that develop integrated indicators and spatially explicit metrics to map the footprint of borealization and identify hot spots are especially encouraged.
   
3. Gadids under Borealization: Ecology, Fisheries, and Management
   Co-chairs: Ben Laurel, David Coté, Caroline Bouchard
   
   Rapid borealization is reshaping SubArctic and Arctic marine ecosystems, with gadid fishes (e.g., cod, pollock, and haddock) playing a central ecological and socio-economic role. This session explores how warming, changing ice regimes, and altered food webs are influencing gadid distribution, life history, trophic interactions, and productivity. We will highlight emerging patterns in recruitment, growth, and predator–prey dynamics, and examine consequences for Indigenous, subsistence, and commercial fisheries. Integrating observations, modeling, and management perspectives, the session aims to identify knowledge gaps and discuss adaptive strategies to sustainably manage gadid populations in rapidly changing northern seas.
   
4. Connections across the Subarctic Atlantic: Physics to Biology, Fjords to Gyres, Surface to Seafloor
   Co-chairs: Warsha Singh, Guðbjörg Ásta Ólafsdóttir, Kumiko Azetsu-Scott
   
   This session explores the interconnected physical and biological processes that structure Subarctic Atlantic ecosystems across spatial and temporal scales. We invite contributions examining how ocean physics, topographic features, and climate variability influence biological communities from fjord systems to the open ocean, and from surface waters to the deep seafloor. Studies integrating observations, modelling, and interdisciplinary perspectives are particularly encouraged. By linking processes across habitats and trophic levels, this session aims to improve understanding of ecosystem connectivity, resilience, and change in a rapidly warming and increasingly variable Subarctic Atlantic.
   
5. The effects of multiple drivers on Arctic and Sub-arctic costal/fjord environments; bridging marine chemistry and biology
   Co-chairs: Sam Rastrick, Melissa Chierici, Agneta Fransson, Naomi Harada, Kumiko Azetsu-Scott
   
   Arctic and Subarctic coastal and fjord ecosystems are highly productive and central to carbon cycling, food security, and local communities, yet they face rapid climate change, increase in natural disaster, and growing industrial pressures. This session invites studies that quantify how climate change (warming, acidification, deoxygenation, freshening, eutrophication), and marine industry e.g. aquaculture, tourism, mineral extraction and sources of other marine contaminants) alter biogeochemistry and biology across environmental gradients. We especially welcome work that integrates laboratory experiments with field observations and bridges marine chemistry with ecology. Contributions that place industry–environment interactions in the context of accelerating climate change are encouraged.

The meeting is organized as a single-track (plenary) program integrating keynote lectures, thematic sessions, lightning talks, and a dedicated poster session.

Oral presentations are 15 minutes in total, including questions. Presenters are kindly asked to upload their presentation files to the conference computer during the break before their session.

Poster presenters are offered the opportunity to present either:

• a poster only, or
• a poster + lightning talk. Lightning talks are 5 minutes with no formal discussion time.

Lightning talk slots will be allocated in advance and communicated to presenters prior to the conference. We will offer poster printing and hanging (at cost). Please indicate your preference to the local organizing committee (ESSAS2026@hi.is) before or on May 10.

Icebreaker

The icebreaker will take place in Litla torg, Háskólatorg, at the University of Iceland on the evening of 22 June (17:00–21:00), with light refreshments.

Conference Dinner

The conference dinner will be held on the evening of 24 June at the Marine and Freshwater Research Institute (MFRI). The MFRI is located in nearby town Hafnarfjörður with a beautiful harbor setting. Expect a 20 minute bus ride to the venue.

The evening includes:

• A short introduction to the MFRI
• A catered dinner in the dining hall
• Bus transport between the University of Iceland / downtown Reykjavík and Hafnarfjörður / MFRI

Bus departure: 18:00 from the University of Iceland.

Note that dinner tickets should be purchased separately.

Sea-angling excursion

A voluntary afternoon sea-angling excursion from Reykjavík harbor will be offered on June 23 (limited capacity; additional cost). Details will be provided closer to the meeting.

Main venue - Saga Building – Room S-261

The meeting is being held in plenary. The conference building is located on the main University of Iceland campus in central Reykjavík. Please see the interactive map for more information.

The conference room and registration desk will be located on the second floor. Please see floor map for more information.

Registration Desk

The registration desk will be open at the Icebreaker event and during the conference.

Catering included in the registration fee:

• Icebreaker
• Coffee breaks: morning & afternoon
• Lunch: provided daily
• Posters session: refreshments included

Additional refreshments are available at Háma coffee shops around campus. Other restaurants at campus are located at the Nordic house and at the National museum.

Getting to Reykjavík

The main international airport is Keflavík International Airport (KEF) located ~45 minutes from Reykjavík. There are some options for Airport to City Transport.

Flybus / Airport Direct

• Most common option
• Tickets can be purchased online, on plane (Icelandair) and at service desks found within the airport.
• Buses run after every flight
• Drop-off at main hotels or central terminal BSÍ (central terminal is conveniently located for city center and university).
• Cost ~3.500 ISK

Taxi

• Cost ~18,000–22,000 ISK
• Faster but expensive. Please see: Taxi to and from KEF

Rental cars

• Many rental car providers have desks at arrivals

Public / city bus (Strætó)

• Few options for many flights but the schedule can be found here. See also information below.

Getting to the Venue

Many hotels and guesthouses in central Reykjavik will be close to the main University campus.

From central Reykjavík:

• 15–20 min walk
• 5–10 min taxi
• Public buses available (Strætó). Routes: 1, 2, 3, 6, 12 and more.
  • Route planner: (stop: Haskoli Islands). Easy to use but you will need their app: Klappið

• Weather: Typically, 8–15°C. Conditions can change quickly; expect a mix of sun, wind, and rain. Layered clothing is recommended.
• Daylight: Very long days (midnight sun conditions). It remains light late into the evening and night.
• There are numerous restaurants and convenience stores in Reykjavik center but fewer options directly in the University area.
• Water: Tap water is safe and of excellent quality.
• Currency: Icelandic króna (ISK). There are ATMs everywhere, but cash is rarely used.
  Credit/debit cards and contactless payments are accepted everywhere. Tipping is not required.
• Safety: Reykjavík is very safe. Emergency number: 112

ESSAS (Ecosystem Studies of Subarctic and Arctic Seas) is an international regional program that seeks to understand how climate variability and change affect marine ecosystems and the people who depend on them in the Subarctic and Arctic.

Members of the ESSAS SSC will contribute to the scientific program and abstract review.

Local Organizing Committee (LOC):
• Guðbjörg Ásta Ólafsdóttir (chair), University of Iceland
• Jacob Kasper (MFRI)
• Warsha Singh (MFRI)
• Einar Pétur Jónsson (MFRI)
• Michelle Valliant (UI)
• Angel Ruiz Angulo (UI)