The Arctic Marine
Ecosystem

Inspired by scientists and artists working
together, this interactive mural depicts a
cross-section of the Arctic marine environment.
It showcases oceanography, biology,
way of life, and how everything is connected.

Swipe through each section of this mural
and discover highlighted points of interest
along way that explain important Arctic marine
features, recent findings, and more. The North Pacific Research Board’s Arctic
Integrated Ecosystem Research Program
involved many different scientists across
all marine science disciplines.

More than 100 scientists, graduate students,
and coastal community members worked
on this program from 2016-2025. They
discovered new insights on Arctic sea
surface temperatures, shifting prey
distributions, the importance of Arctic cod,
harmful algal blooms, and much, much more.
 Northern Chukchi Sea ecosystem painting collaboratively developed
by artist Klara Maisch and scientists Seth Danielson, Claudine Hauri,
and Andrew McDonnell. Additional contributions from Arctic Program
scientists and artist Molly Trainor. Swipe to explore Polar bears use their keen sense of smell to locate ringed seal breathing holes and snow-covered birth lairs hidden within the sea ice. Once they detect a likely spot, they wait patiently or break through the snow to catch seals when they surface or rest inside their lairs. Environmental changes affect how ringed seals use sea ice for protection and potentially expose them to more predation. Arctic Marine Predators Ringed seals are carnivores that primarily eat fish and invertebrates, with a strong reliance on Arctic cod, saffron cod, krill, and shrimp. Often hunting alone, they dive beneath the ice in dark conditions, relying on their whiskers to detect movement in the water. Seals often synchronize their dives with daily movements of fish and can change strategies seasonally to balance energy use, showing an ability to adapt to shifting Arctic ecosystems. Foraging Behavior As sea ice forms, a layer of very cold (<2°C), dense water forms near the sea floor. This pool of water restricts the northward movement of subarctic commercially important fishes such as Pacific cod and walleye pollock. As waters in the Chukchi and northern Bering Sea have warmed, the cold pool has weakened, allowing subarctic species to venture farther northward affecting arctic species, including Arctic cod. The Cold Pool Small But Mighty Although small, phytoplankton drive the Arctic carbon cycle. They absorb sunlight and carbon dioxide from surface waters and convert it to organic matter that fuels the food web. When they die or are eaten by larger organisms (e.g., zooplankton, fish, whales), some of this carbon sinks to the ocean bottom, effectively storing carbon away from the atmosphere for long periods. When the Arctic Ocean warms, the carbon cycle becomes less stable and can shift from storing carbon to releasing more of it. This may cause sea ice loss, harmful algal blooms, and ocean acidification. Arctic cod are smaller than Pacific cod and highly adapted to cold, ice-covered waters. They have relatively high lipid (fat) content and are a higher energy fish for top predators such as seals, whales, and seabirds. Their abundance and distribution strongly influence the survival of many Arctic animals. With warmer Arctic waters, less nutrient-rich fish may replace Arctic cod with potential impacts for top predators. Arctic Cod Importance Stratification refers to the layering of water in the ocean based on differences in temperature and salinity, with fresher water often sitting on top of denser, saltier water. Mixing driven by winds, currents, and ice formation or melting disrupts stratification and redistributes heat, nutrients, and gases like oxygen and carbon dioxide throughout the water column. Stratification plays a role in separating the organisms in surface waters from those at depth and changes in ocean layering may restructure ocean communities. Ocean Stratification
And Mixing Sea ice algae form the base of polar marine food webs, providing an early-season, highly nutritious source of energy for organisms like zooplankton, fish, and even larger predators. They also play a crucial role in carbon cycling by capturing carbon dioxide during photosynthesis and supporting overall ecosystem productivity in ice-covered oceans. Sea Ice Algae Walrus Diet The Chukchi Sea is a shallow basin with a highly nutrient-rich benthic sea floor. Organisms like clams, worms, sea stars, crabs, and other invertebrates call this dark, cold environment their home. Walrus use their sensitive whiskers to detect prey and they use their lips and tongue to suck it from the thick mud. Disturbing the ocean floor like this resuspends dead, organic material and catalyzes the carbon cycle. The Arctic marine spring bloom is a rapid surge of phytoplankton growth that occurs when sea ice melts and sunlight returns. It provides a critical pulse of energy that fuels the entire Arctic food web from zooplankton to fish, seabirds, and marine mammals. If the timing is off—such as phytoplankton blooming before zooplankton are ready to feed—much of that energy is wasted, which can reduce food availability up the food chain and disrupt growth, reproduction, and survival of many Arctic species. The Spring Bloom Zooplankton are tiny drifting animals in the ocean, including organisms like copepods and krill, that feed on phytoplankton and form a key link between microscopic producers and larger animals such as fishes, seabirds, and whales. As the ocean warms and sea ice declines, shifts in phytoplankton communities (for example, increases in smaller or lower-energy algae or changes in bloom timing) can reduce the lipid (fat) content of zooplankton, meaning they may provide less energy to fish and other predators even if their numbers remain stable. Role of Zooplankton Some Pacific salmon species (especially pink and chum salmon) are increasingly being found and even spawning in Arctic Alaska river systems on the North Slope, such as the Anaktuvuk and Itkillik rivers, which flow into the Arctic Ocean. These observations suggest that warming ocean and river temperatures are opening “new corridors” that allow salmon to move farther north than they historically did. To date, only the Mackenzie River in Arctic Canada has a self-sustaining stock, but scientists are seeking to determine if other Arctic river systems might also soon support these fish. Migrating Fish Species Shifts in Subarctic Groundfish As subarctic groundfish species move northward into the Arctic due to warming ocean temperatures and reduced sea ice, they are altering food web dynamics by competing with native species like Arctic cod for food and habitat. These incoming species can also prey on Arctic cod and other cold-adapted fishes and crabs, potentially reducing their abundance and weakening a key food source for consumers such as seals, seabirds, and whales. Alaska Native communities have long maintained subsistence lifestyles centered on seasonal harvesting of fishes, seabirds, and marine mammals to provide food, materials, and cultural continuity. These practices are deeply connected to local ecosystems and knowledge systems, relying on careful timing, skill, and respect for wildlife to sustain both communities and resources over generations. Traditional Ways of Life Bowhead whales are some of the longest-living mammals on Earth, reaching ages over 200 years. They produce some of the loudest and most complex songs of any whale species, which may help them communicate across vast, icy oceans. They also play an important role in the Arctic food web, both as a grazer on zooplankton and as a food source for many Alaska Native communities, especially Iñupiat and Yupik peoples. Bowhead whales are central to subsistence life, providing food, oil, and materials that support cultural traditions, community sharing, and seasonal harvesting practices that have continued for generations. The Bowhead Whale Changing ocean conditions—especially warming waters, shifting sea ice, and more variable weather—are making subsistence harvests less predictable for many Alaska coastal communities. Fishes, seals, whales, and seabirds are changing their migration routes and timing, and thinning or unstable sea ice and larger waves are making hunting more dangerous and shortening traditional harvesting seasons. People are traveling farther to hunt and fuel prices are increasing in rural communities, therefore hunting has become more expensive. At the same time, stronger storms and coastal erosion are affecting access to fishing and hunting camps. The Ocean Is Changing The Seafloor Is Alive Respiration in Arctic seafloor (benthic) communities is the process where organisms like worms, clams, bacteria, and other invertebrates break down organic material and use oxygen, releasing carbon dioxide as a byproduct. This activity is a key part of recycling carbon that sinks from the surface ocean, returning some of it back into the water column instead of permanently storing it in sediments.

Because so much organic carbon from phytoplankton eventually settles to the seafloor, benthic respiration strongly influences the Arctic carbon cycle by determining how much carbon is stored long-term versus re-released back into the ocean and atmosphere. Changes in temperature, oxygen levels, and food supply can therefore shift how efficiently the seafloor acts as a carbon “sink” or “source.”