Every winter, people travel to Tromsø hoping to see humpback whales and orcas.

But the story of Northern Norway’s winter whales does not really begin with whales.

It begins with a much smaller animal.

Herring.

Billions of Norwegian spring-spawning herring move through the Northeast Atlantic as part of one of the region’s most important marine migrations.

At certain times of year, enormous numbers can concentrate in northern Norwegian waters.

And wherever so much food gathers in one place, predators notice.

Cod.

Saithe.

Seabirds.

Orcas.

And humpback whales.

This is the ecological engine behind Northern Norway’s winter whale season.

Understanding the herring changes the way you understand the whales.

Instead of asking:

“Why do humpback whales come to Tromsø?”

the better question is:

“Where have the herring gone this winter—and which whales have followed them?”

Meet the Fish Behind the Whale Season

The fish at the centre of this story is the Norwegian spring-spawning herring, often abbreviated NSSH.

It is one of the great migratory fish populations of the Northeast Atlantic.

Herring are not large predators.

They feed mainly on plankton.

Individual fish may seem insignificant beside a 30-tonne humpback whale.

Their power comes from numbers.

Herring form dense schools containing huge numbers of fish moving together.

Norway’s Institute of Marine Research describes Norwegian spring-spawning herring as an ecologically important prey species for fish, seabirds and whales. Read the Institute of Marine Research’s species overview

That single relationship explains much of what happens during the winter whale season.

One herring is a small meal.

Millions gathered into dense schools are an enormous concentration of energy.

And humpback whales are extraordinarily well designed to exploit exactly that kind of opportunity.

The Herring Do Not Stay in One Place

One of the most important things to understand is that Norwegian spring-spawning herring are migratory.

Their year involves movements between different areas used for:

• Feeding
• Wintering
• Spawning
• Growing up

The traditional pattern looks roughly like this:

Spring and summer

After spawning, adult herring travel into the Norwegian Sea to feed.

Their main food includes zooplankton, particularly Calanus finmarchicus.

The fish use productive oceanic feeding areas through spring and summer.

Autumn

As the feeding period ends, large parts of the population begin moving toward wintering areas.

The Institute of Marine Research describes the traditional autumn migration toward coastal and fjord areas in Northern Norway as beginning around September and October.

Winter

The herring can form enormous concentrations in wintering areas.

In recent years, important concentrations have occurred in northern fjord systems such as:

• Kvænangen
• Altafjorden
• Sørøysundet
• Surrounding offshore waters

And this is where the whale story becomes particularly interesting.

Toward spawning

As winter progresses, mature herring eventually leave their wintering grounds and move toward spawning areas.

Historically, much of the stock undertook a long southward migration toward spawning grounds along the Norwegian coast.

But even this part of the story is changing.

Herring Migration Is Not a Fixed Route

It is tempting to draw the herring migration as a simple arrow on a map.

Summer here.

Winter there.

Spawn somewhere farther south.

Repeat next year.

Nature is much more complicated.

Herring have changed their wintering areas dramatically over time.

For example, large numbers wintered near Kvaløya west of Tromsø during the mid-2010s.

Then the distribution changed.

By the following winters, major concentrations had shifted northeast toward Kvænangen, roughly 100 kilometres from Tromsø.

The Institute of Marine Research has described this wintering behaviour as highly variable: herring may return to the same region for several winters and then suddenly establish a different wintering area. Read the Institute’s explanation of changing herring wintering areas

This matters directly to whale watching.

Because:

when the herring move, the feeding opportunities for whales move too.

Recent Herring Research Has Made the Story Even More Interesting

The migration story became more surprising in 2025.

A major study published in Nature, led by scientists from Norway’s Institute of Marine Research, documented an approximately 800-kilometre northward shift in the main spawning distribution of Norwegian spring-spawning herring.

Traditionally, much of the population migrated south to spawn around Møre.

But from 2021 onward, the main spawning pattern shifted dramatically north toward Lofoten.

The researchers linked this change partly to what they described as the loss of collective migration memory.

Older herring appear to play a role in transmitting established migration routes to younger fish.

After fishing pressure reduced the number of experienced older individuals, a large younger generation established a different migration pattern—and much of the population eventually followed it. Read the 2025 Nature study on changing herring migration culture

That discovery is important far beyond fisheries science.

It demonstrates something every whale-watching operation needs to understand:

prey migrations are not permanently fixed.

And neither are the predators that depend on them.

Where Were the Herring Most Recently?

Recent scientific surveys continue to show important wintering concentrations in the fjord systems north of Tromsø.

An Institute of Marine Research acoustic survey conducted in December 2025 investigated herring distribution around Altafjorden, Sørøysundet, Kvænangen and Lopphavet.

By February 2026, fisheries observations indicated that herring were moving from wintering areas north of Tromsø toward their spawning areas.

That does not mean next winter will look identical.

And that is exactly the point.

Whale watching in Northern Norway requires following a moving ecological system rather than travelling to a permanent “whale location.”

Why Do Humpback Whales Care About Herring?

Because a humpback whale needs an enormous amount of energy.

Humpbacks are baleen whales.

They do not have teeth.

Instead, hundreds of baleen plates hang from the upper jaw.

Their feeding strategy is based on capturing large volumes of small prey at once.

A dense herring school is therefore an extraordinary opportunity.

Instead of chasing individual fish one by one, a humpback can engulf an enormous mouthful of:

water + herring

and then force the water back out through its baleen.

The fish remain behind.

This is one reason humpbacks are so effective at exploiting schooling prey.

NOAA describes humpbacks as flexible feeders capable of using bubbles, sound, their pectoral fins and coordinated movements to help concentrate prey before engulfing it. Explore NOAA’s humpback-whale biology guide

What Is Lunge Feeding?

One of the most dramatic humpback behaviours is lunge feeding.

Imagine a concentrated school of herring.

A humpback accelerates toward it.

Then the whale opens its mouth.

The pleated grooves underneath the jaw expand dramatically.

Instead of maintaining a streamlined shape, the whale temporarily becomes an enormous biological scoop.

Water and fish rush inside.

At the surface, this can look explosive.

You may see:

• Herring scattering
• Seabirds diving
• Water erupting
• The humpback’s head emerging
• An enormous open mouth
• Several whales feeding in the same area

It can be one of the most spectacular behaviours in whale watching.

But it is important to keep expectations realistic.

Humpback whale does not automatically mean surface lunge feeding.

A whale may feed below the surface.

It may travel.

It may dive repeatedly.

It may simply move through the area.

Dramatic surface feeding is something nature provides, not something a safari can schedule.

What About Bubble-Net Feeding?

Humpbacks are also famous for using bubbles to manipulate schooling prey.

A whale—or sometimes several whales—can release bubbles underwater.

The bubbles rise and may help concentrate fish into a tighter area.

The humpbacks can then move through the concentrated prey.

Different humpback populations and groups show variations in how they use bubbles and other feeding strategies.

These behaviours are not simply instinctive copies performed identically everywhere.

Humpbacks are flexible predators capable of adjusting their methods to local prey and conditions.

That adaptability helps explain why they can exploit rich herring concentrations in Northern Norway.

Why Are Seabirds Important During a Feeding Event?

A good guide does not search only for whales.

They search for signs of the whole feeding system.

When herring are pushed toward the surface, seabirds may begin gathering.

Suddenly an apparently empty patch of fjord becomes active.

Birds start diving.

Fish disturb the surface.

Orca fins appear.

A humpback blow rises farther away.

The birds are not merely background wildlife.

They can be clues.

They may reveal that something important is happening underneath the surface.

Watching a feeding event therefore means learning to watch the entire environment—not simply waiting for a whale to appear.

Orcas Are Part of the Same Story

Humpbacks are not the only major predators attracted by winter herring.

Orcas are too.

But the two species solve the same feeding problem in completely different ways.

Orcas are toothed, highly social predators.

Norwegian orcas can cooperate to concentrate herring before striking or stunning fish with powerful tail movements.

Humpbacks are enormous baleen feeders capable of engulfing concentrated patches of fish.

Sometimes these two strategies bring both species to the same food patch.

Do Humpbacks and Orcas Hunt Together?

This requires some careful wording.

You may hear people say:

“The humpbacks and orcas hunt together.”

That makes the relationship sound more cooperative than scientists have actually demonstrated.

A fascinating Northern Norwegian study examined orca and humpback feeding events around Andfjord between 2013 and 2016.

Researchers observed killer whales feeding on 59 occasions.

Humpback whales were involved in 47 of those feeding events.

The evidence suggested that humpbacks frequently joined herring patches where feeding orcas were already active. Read the published Northern Norway mixed-feeding study

That tells us something remarkable.

The humpbacks may be taking advantage of herring that orcas have already helped concentrate.

But it does not necessarily mean the two species are deliberately cooperating as one hunting team.

A better description is:

they can exploit the same concentrated prey patch.

That distinction matters.

Why Winter Herring Can Change a Humpback’s Migration

There is another fascinating layer to this story.

Humpback whales themselves are great migrators.

North Atlantic humpbacks generally move between high-latitude feeding areas and warmer breeding grounds farther south.

Whales feeding in Norwegian waters have been linked through photo-identification to breeding areas including:

• The West Indies
• Cape Verde

Some of these migrations cover thousands of kilometres.

But rich winter herring concentrations in Northern Norway create an unusual opportunity:

keep feeding before heading south.

One Whale Showed Scientists Just How Complex That Journey Can Be

A remarkable satellite-tracking study followed a pregnant female humpback tagged in Northern Norway.

She was tracked for 321 days.

Her journey included:

Northern Norway → Iceland → West Indies breeding grounds → Barents Sea → Norway

before returning again to the same northern Norwegian fjord system.

The study demonstrated that an individual humpback could use several feeding areas during one annual migration cycle—and could continue feeding in coastal Norway during winter before completing its long migration south. Read the full humpback migration study

This completely changes the simplistic picture of:

summer = feeding

and

winter = breeding.

For some Northeast Atlantic humpbacks, a rich winter herring resource can extend the feeding season surprisingly late.

Imagine the Energy Decision

A humpback whale eventually faces a trade-off.

Farther south are breeding grounds.

But here in Northern Norway is a huge concentration of energy.

Herring.

Every additional successful feeding event allows the whale to build or maintain valuable energy reserves.

That matters because long-distance migration is expensive.

Reproduction is expensive.

Pregnancy is expensive.

Lactation is extremely expensive.

The decision of when to leave northern feeding grounds therefore exists within a much larger biological strategy.

The whale is not “late.”

It is responding to opportunity.

Are the Same Humpbacks Returning to Norway?

Some individuals are.

Humpback whales can be identified from the unique pigmentation patterns, scars and shape of their tail flukes.

Researchers photograph these tails and compare them across regions.

Photo-identification has connected whales seen in Norwegian feeding areas with animals later observed thousands of kilometres away.

For example, research involving humpbacks from the Cape Verde breeding population found numerous individuals that had also been identified in feeding grounds around Norway. See the NOAA-hosted research on Norway–Cape Verde humpback movements

So when a humpback raises its tail in Northern Norway, you are not simply seeing “a humpback.”

You may be looking at an individual that has crossed a significant part of the North Atlantic.

And researchers may already know parts of its history.

Why Do Tail Photographs Matter?

The underside of a humpback whale’s tail is often individually distinctive.

Differences include:

• Black and white pigmentation
• Scars
• Shape
• Notches
• Edge patterns

These characteristics allow researchers to build photo-identification catalogues.

Over time, repeated sightings can reveal:

• Migration routes
• Feeding-site fidelity
• Associations
• Survival
• Connections between feeding and breeding areas

This is one reason a clear photograph of a fluke can have scientific value beyond being a beautiful wildlife image.

Does More Herring Automatically Mean More Humpbacks?

Not necessarily.

Marine ecosystems rarely work through one simple equation.

A huge herring concentration does not automatically mean:

huge numbers of humpbacks exactly above it.

Whale distribution can also depend on:

• How concentrated the fish are
• Depth
• Accessibility
• Other prey
• Ocean conditions
• Individual whale movements
• Competition
• Migration timing

There may be enormous quantities of herring somewhere in the region without those fish being concentrated in a form that produces spectacular surface feeding.

So even when scientists know herring are present, wildlife encounters remain unpredictable.

Why Whale Locations Can Change Between Winters

This is one of the most important lessons from the herring story.

The famous winter-whale locations in Northern Norway have changed before.

At different periods, large herring concentrations—and therefore much of the visible whale activity—have occurred around different parts of the coast.

That means a destination should not build its entire whale story around one permanent fjord.

The ecosystem moves.

The operation must respond.

Tromsø works today primarily as a departure hub.

The actual whale-searching areas may be considerably farther north.

That is why Arctic Whale Tours operates the winter safari as a full-day journey, currently from November through January aboard MS Alba. See current Winter Whale Safari details

So Why Is the Tromsø Safari So Long?

Because the boat is not simply travelling to a fixed buoy labelled:

WHALES HERE.

The crew must reach the wider areas where winter feeding activity is occurring and then search.

Whale location can change.

Weather changes.

Herring distribution changes.

Sometimes the animals are found relatively quickly.

Sometimes searching takes longer.

The full-day format reflects the geography and ecology of modern winter whale watching from Tromsø.

That journey is not wasted time.

It is part of following a living ecosystem.

What Might You See When Herring Are Near the Surface?

A productive feeding area can reveal itself gradually.

At first:

nothing.

Then:

birds.

A few gulls begin circling.

More arrive.

The surface becomes disturbed.

Small silver fish flash near the water.

Then a dorsal fin appears.

Perhaps an orca.

Then another.

Farther away:

a blow.

A humpback surfaces.

The activity increases.

But feeding events do not always look this dramatic.

Sometimes most of the important behaviour happens beneath the surface.

Experienced whale watching means learning not to judge the quality of an encounter only by how spectacular it looks on Instagram.

Herring Connect the Entire Food Web

The herring migration matters because herring occupy a powerful position in the marine food web.

They consume plankton.

Then they become prey.

The Institute of Marine Research identifies herring as food for:

• Cod
• Saithe
• Other predatory fish
• Seabirds
• Whales

So a dense winter herring concentration represents much more than food for humpbacks.

It is a moving concentration of energy through the ecosystem.

This is what a good whale safari should help guests understand.

The whale is the most visible part of the story.

It is not the whole story.

Why Responsible Whale Watching Matters Especially During Feeding

Feeding is not entertainment.

For the whale, it is essential biological work.

An animal may have travelled enormous distances.

It may soon travel thousands more.

The herring patch represents energy.

Vessels should therefore avoid unnecessarily disrupting animals actively feeding.

That means paying attention to:

• Direction of travel
• Feeding behaviour
• Other whales
• Other vessels
• Space
• Speed
• Sudden course changes

The goal should never be:

get between the whale and the fish so guests get a better photograph.

The better objective is:

observe the feeding system without becoming part of it.

Does the Herring Migration Guarantee Whales?

No.

This needs to remain completely clear.

The ecological relationship is strong.

But it is not a booking guarantee.

Herring can occur over enormous areas.

Whales move independently.

Weather can restrict access.

Feeding may happen far from where vessels can reasonably operate.

A winter safari is therefore always a search for wild animals.

Arctic Whale Tours currently focuses primarily on:

• Orcas
• Humpback whales

during the Tromsø winter season.

Other cetaceans may occur.

None can be guaranteed.

When Is the Best Time to See Humpbacks Feeding on Herring?

We would not claim one specific week.

The main AWT winter season runs from November through January.

But herring migration, whale abundance and feeding intensity do not divide themselves cleanly according to calendar months.

One season can develop differently from another.

If you are deciding between months, it is more useful to choose according to:

• Daylight
• Polar Night experience
• Wider Tromsø itinerary
• Availability
• Your preferred winter atmosphere

rather than believing one month automatically provides the most humpbacks.

For a complete comparison, see Best Time for Whale Watching in Tromsø: November, December or January?

Can You See Humpbacks During the Polar Night?

Yes.

Much of the winter feeding season overlaps the Polar Night.

The Polar Night does not mean complete 24-hour darkness.

Around midday there are several hours of Arctic twilight.

That is when the primary wildlife search takes place.

Humpbacks can actually be visually striking in winter conditions.

A blow rises against snowy mountains.

The huge dark back breaks blue-grey water.

Then the tail appears against a pale Arctic sky.

For a detailed explanation of the light, read Whale Watching During the Polar Night in Tromsø

Humpback or Orca: What Are You Actually Watching?

Both species may be exploiting the same food source.

But their encounters feel very different.

Orcas often create a more active, social scene.

Several animals may surface in different directions.

Humpbacks create a different sense of scale.

A blow.

A huge back.

A tail.

Then, if feeding reaches the surface, an enormous mouth moving through thousands of fish.

If you want to understand the differences in detail, continue with Orca vs Humpback Whale: What Might You See from Tromsø?

The Herring Are Why We Should Never Promise Exactly Where the Whales Will Be

Tourism prefers certainty.

Nature does not.

We would love to say:

“Every December, the whales are exactly here.”

The scientific evidence tells a much more interesting story.

Herring have shifted wintering areas.

Their spawning migration has changed.

A younger generation helped establish a new migration route.

Whales respond to this moving resource.

And humpbacks themselves may alter the timing of enormous ocean migrations to exploit winter feeding opportunities.

This is not an inconvenience in the story.

It is the story.

A Winter Whale Safari Is Really an Ecosystem Safari

Most guests buy a ticket because they want to see a whale.

That is understandable.

But once you understand the herring, you begin noticing much more.

The birds gathering above the water.

The surface movement of fish.

The positioning of the orcas.

The arrival of a humpback.

The relationship between predator and prey.

The depth of the fjord.

The changing Arctic light.

The whale becomes part of a larger system rather than an isolated attraction.

That is when whale watching becomes more interesting.

One Small Fish, an Enormous Arctic Story

A herring may grow to only a fraction of the size of a humpback whale.

Yet collectively, these small fish can influence the movements of some of the largest animals on Earth.

They move from feeding grounds.

They gather for winter.

They change migration routes.

They head toward spawning areas.

And behind them comes an entire ecosystem of predators looking for opportunity.

Among them:

humpback whales.

A whale you see surfacing in a northern Norwegian fjord may eventually travel thousands of kilometres toward tropical breeding grounds.

But for now, it is here.

Because the food is here.

That simple connection—

herring → whale

—is the foundation of Northern Norway's winter whale season.

And once you understand it, the question changes.

Instead of asking:

“Where are the whales?”

you begin asking:

“What is happening in the ocean that brought them here?”

That is a much better place to start.

Plan Your Winter Whale Safari from Tromsø

Arctic Whale Tours operates its winter whale safari from Tromsø during the November–January season, travelling aboard MS Alba into the northern fjords in search of winter whale activity.

No particular species is guaranteed.

The search changes with:

• Wildlife
• Herring distribution
• Weather
• Sea conditions

And that flexibility is essential.

Because the ecosystem itself is moving.

Continue Exploring the Winter Whale Story

Start with Do Orcas and Humpbacks Come to Tromsø Every Winter?

Compare the two primary winter species in Orca vs Humpback Whale: What Might You See from Tromsø?

Planning your dates? Read Best Time for Whale Watching in Tromsø

For the complete destination guide, visit The Ultimate Guide to Whale Watching in Tromsø

Or check current dates and availability for the Winter Whale Safari from Tromsø

Frequently Asked Questions

Why do humpback whales come to Northern Norway in winter?

Dense concentrations of Norwegian spring-spawning herring create valuable feeding opportunities in northern Norwegian waters. Humpbacks can exploit these schools before continuing other parts of their annual migration.

What is Norwegian spring-spawning herring?

It is a large migratory Atlantic herring population that moves between feeding, wintering and spawning areas in the Northeast Atlantic and along Norway.

When do the herring arrive in Northern Norway?

Traditionally, large parts of the population move northeast toward wintering areas during autumn, around September and October. The precise distribution changes between years.

Where do the herring spend winter?

The location changes. In recent winters, important concentrations have occurred around fjord systems north of Tromsø including Kvænangen and Altafjorden, as well as surrounding waters.

Do the herring always return to the same fjord?

No. Herring wintering areas can change substantially. Scientists have documented major shifts between different coastal and offshore wintering areas.

Why did the herring migration change?

Recent research indicates that migration behaviour includes socially learned components. A 2025 Nature study linked a major shift in the herring's spawning migration partly to reduced numbers of experienced older fish and the emergence of a strong younger generation that established a different route.

What do humpback whales eat in Northern Norway?

Herring can be an important winter prey. Humpbacks can also feed on other small schooling fish and krill in other parts of their range.

How do humpback whales eat herring?

Humpbacks are baleen whales. They can engulf large amounts of fish-filled water and then filter the water out through baleen plates, retaining the prey.

What is lunge feeding?

Lunge feeding occurs when a humpback accelerates into concentrated prey with its mouth open, engulfing a large volume of water and fish.

Do humpbacks and orcas hunt herring together?

Both can feed on the same herring patches. Northern Norwegian research has documented humpbacks joining feeding events where killer whales were already active, but this should not automatically be described as deliberate cooperative hunting between the two species.

Where do Norwegian humpbacks go after winter?

North Atlantic humpbacks using Norwegian feeding areas can migrate toward lower-latitude breeding grounds, including the West Indies and Cape Verde. Individual migration patterns and timing vary.

Are humpbacks guaranteed during a Tromsø whale safari?

No. Humpbacks, orcas and all other cetaceans are wild animals. Their location and presence cannot be guaranteed.

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