Weaving together ancient knowledge and cutting-edge technology to secure the future of northern fisheries and ecosystems
In the frigid waters of the Arctic and Subarctic seas, a silent revolution is underway. As the planet warms, these sensitive marine ecosystems are transforming at an unprecedented pace. The Ecosystem Studies of the Subarctic and Arctic Seas (ESSAS) Annual Science Meeting serves as a critical hub where scientists converge to decode these changes, weaving together ancient knowledge and cutting-edge technology to secure the future of northern fisheries and the communities that depend on them 1 .
The Arctic is warming at a rate three to four times faster than the global average, causing dramatic shifts in marine environments 1 . The annual ESSAS Open Science Meeting, scheduled for June 24-26, 2025, in Tokyo, Japan, embodies a comprehensive effort to understand these changes under the theme "Past, Present and Future of Marine Biodiversity and Ecosystems." 1
These northern waters are not just icy wildernesses; they are pillars of global ecological health and food security. Small forage fish like herring and mackerel form the foundation of intricate food webs, supporting everything from massive whales to seabird colonies. However, ineffective management and overexploitation have left many of these species dangerously vulnerable 2 .
The Arctic is warming 3-4x faster than the global average, threatening marine ecosystems that support global food security 1 .
Theme: Past, Present and Future of Marine Biodiversity and Ecosystems
Date: June 24-26, 2025
Location: Tokyo, Japan
The 2025 ESSAS meeting is organized around thematic sessions that tackle the most pressing issues in northern fisheries research.
To understand how scientists are untangling these complex changes, consider a groundbreaking study from Indonesia that showcases methodologies directly applicable to northern seas. Researchers there faced a familiar problem: a critical lack of data on deep-water bottom fish (demersal fish), which are essential for both ecosystems and local economies 9 .
The team used a single-beam echosounder (SBES), a more accessible alternative to expensive multibeam systems, to survey the seabed. This technology emits sound pulses and captures the returning signals, which contain information about both the seabed's physical characteristics and the fish present in the water column 9 .
The SBES collected multiple "echo-envelope features" such as Bottom Peak (BP1, BP2) to gauge substrate hardness and roughness. These seabed characteristics were integrated with environmental data like depth and geographic coordinates 9 .
To handle the complex, non-linear relationships in the data, researchers employed powerful machine learning algorithms, specifically XGBoost and Support Vector Regression (SVR), to model and predict fish distribution based on the integrated habitat data 9 .
The study successfully demonstrated that depth and seabed hardness (BP2) were the primary factors determining where demersal fish congregate 9 . The machine learning models, particularly XGBoost, proved highly effective at mapping these habitat preferences.
The table below shows the performance of the different models in predicting key fish distribution metrics, with XGBoost consistently achieving higher R² values, indicating a better fit to the observed data 9 .
| Predicted Variable | Model | R² Score | Mean Squared Error (MSE) |
|---|---|---|---|
| Volume Backscattering Strength (SVSED) | XGBoost | 0.89 | 0.74 |
| SVR | 0.85 | 1.12 | |
| Mean Target Strength (TSc) | XGBoost | 0.91 | 0.68 |
| SVR | 0.87 | 0.98 | |
| Fish Density (Log-transformed) | XGBoost | 0.85 | 0.08 |
| SVR | 0.81 | 0.11 |
| Variable | Description | Ecological Significance |
|---|---|---|
| Depth | Water depth at sampling location | A master variable that influences light, pressure, temperature, and species composition |
| BP1 (Bottom Peak 1) | An acoustic metric related to substrate roughness | Rougher surfaces (e.g., rocky reefs) provide complex habitat structure for shelter and feeding |
| BP2 (Bottom Peak 2) | An acoustic metric related to substrate hardness | Indicates sediment type (e.g., soft mud vs. hard sand), which influences burrowing behavior and prey availability |
| Geographic Coordinates | Latitude and Longitude | Captures broader regional gradients and proximity to features like currents or river plumes that affect productivity |
Modern marine ecology relies on a diverse array of tools, from physical instruments to biological reagents.
| Tool/Reagent Category | Specific Examples | Function in Marine Research |
|---|---|---|
| Acoustic Survey Equipment | Single-beam and Multibeam Echosounders 9 | Maps seabed topography, classifies substrates, and detects fish schools in the water column |
| Animal Tracking Devices | Biotelemetry and Biologging Tags 1 | Tracks animal movement, behavior, and physiology to understand responses to environmental change |
| Laboratory Reagents | Formaldehyde, Paraformaldehyde 5 | Used as fixatives to preserve tissue samples (e.g., fish gonads, plankton) for later biological analysis |
| Cell Culture Materials | Fetal Bovine Serum, L-Glutamine 5 | Supports the growth of cell lines used in toxicology studies (e.g., testing the effects of pollutants) |
| Molecular Biology Reagents | Antibodies (e.g., NF-κB p65), DNA stains (e.g., Hoechst 33342) 5 | Used in biochemical assays to study cellular responses to stress in marine organisms |
Advanced echosounders map underwater terrain and detect marine life distributions 9 .
Biologging tags monitor species movements and behaviors in changing environments 1 .
Laboratory reagents enable cellular and molecular studies of marine organisms 5 .
A recurring and vital theme in modern fisheries science is the recognition that scientific data alone is not enough. Session 9 of the ESSAS meeting is dedicated to "Knowledge co-production and citizen science," highlighting case studies from Arctic and sub-arctic communities 1 . This approach integrates generational knowledge from local and Indigenous peoples with scientific methods to create a more complete and applicable understanding.
A powerful example comes from the Commonwealth of the Northern Mariana Islands, where NOAA scientists and local fishers collaborated on a first-of-its-kind bottomfish survey. Local fisher Lino Tenorio related the experience to "being asked to get on a rocket to the moon," underscoring its significance 3 .
"We each hold pieces to the puzzle... Fishers understand the fishery, including fish movements, spawning patterns, seasonality, and fluctuations—knowledge that scientists must have to complete the overall picture." 3
The challenges facing northern fisheries are immense, but the scientific community is responding with unprecedented collaboration and innovation. By merging insights from the past with the technologies of the present, researchers are building robust forecasts and scenarios to guide sustainable management.
Session 8 of the ESSAS meeting, "The Future of Marine Ecosystem Research," is dedicated to this effort, using forecasts, projections, and scenarios to explore what the Arctic and subarctic seas might look like in the years to come 1 . This forward-looking science is crucial for informing policy and conservation efforts.
The future of these vital ecosystems depends on our ability to continue bridging disciplines—from biochemistry to telemetry, from machine learning to traditional knowledge. As the 2025 ESSAS meeting will emphasize, it is only by weaving these threads together that we can hope to manage the profound changes underway and ensure the resilience of northern fisheries for generations to come.
Session 8 of ESSAS 2025: "The Future of Marine Ecosystem Research" uses forecasts and scenarios to explore future Arctic and subarctic marine environments 1 .