When the Dust Blows, the Salmon Grow

Why Replenishing Nature’s Missing Dust Is the Key to Restoring North Pacific Fisheries

The image above shows the summer 2024 eruption of the Russian Shiveluch Volcano.

For decades, we have debated why salmon populations rise and fall across the North Pacific. We have argued about fishing pressure, hatcheries, predators, climate change, ocean temperatures, and management strategies.

All of these matter.

But beneath them lies something far more fundamental — something older than fisheries policy and more powerful than seasonal weather:

The mineral dust cycle that feeds the ocean’s pastures.

When the dust and volcanic ash blow, the plankton grow.
When the plankton grow, young salmon survive.
When young salmon survive, fishing communities thrive.

And when the dust falters, the system struggles — no matter how carefully we manage it.

An Ocean Pasture vs. A Clear Blue Desert

The Gulf of Alaska and the broader North Pacific, when healthy, are not empty expanses of blue water. They are living pastures, vast fields of microscopic plants — phytoplankton — that convert sunlight and carbon dioxide into life.

These phytoplankton harvest sunlight and CO2 to grow
They feed zooplankton.
Zooplankton feed forage fish.
Forage fish feed salmon.
Salmon feed coastal cultures and economies.

But unlike land pastures, the ocean’s productivity is not controlled by rainfall or fertilizer. It is controlled by vital mineral dust carrying infinitesimal amounts of iron.

And iron arrives from the sky.

The Two Great Dust Engines of the North Pacific

For millennia, two natural systems have supplied the iron that sustains North Pacific plankton:

1. Asian desert dust — lifted from the Gobi and Taklamakan deserts each spring and carried eastward across the Pacific.
2. Volcanic ash — episodic but powerful eruptions from Kamchatka and the Aleutian arc that inject mineral-rich particles high into the atmosphere.

These dusts settle over the ocean, dissolve, and release iron and trace nutrients into surface waters. In iron-limited regions like the Gulf of Alaska and Bering Sea, even small increases can trigger large biological responses.

This is not speculation. Satellite imagery, oceanographic surveys, and historical fisheries records all show the same pattern:

When mineral dust inputs increase, plankton blooms intensify.

And when plankton blooms intensify, salmon respond.

2025: A Clear Ecological Signal

In 2025, Alaska experienced an especially large pink salmon catch — approximately 119 million fish. But pink salmon were not alone.

Sockeye returns were strong.
Chum abundance increased.
Average weights for several planktivorous species rose or held steady despite higher numbers of fish.

These species share a critical trait: during their early marine life, they are highly dependent on plankton-based food webs.

The signal is consistent with especially favorable ocean pasture conditions during 2023 and 2024 — precisely when these young salmon entered their ocean.

And what happened in those years?

The dust blew.

Here’s a glimpse at the State of Alaska report on the extraordinary salmon catch in 2025.

Headline Data (ADF&G, November 4, 2025)

• Total 2025 harvest: 194.8 million salmon, valued at $541 million
• Pink salmon: 119 million fish (61% of harvest), valued at $114 million
• Sockeye: 53 million fish (27%), valued at $315 million
• Chum: 20 million fish (10%), valued at $78 million
• Coho: 2 million fish, valued at $21 million
• Chinook: Exceeded forecast by 26%

2023–2024: A Rare Alignment of Natural Forcing

During the critical spring and summer seasons of 2023 and 2024:

• Significant volcanic eruptions in Kamchatka lofted ash into the North Pacific.
• Multiple strong Asian dust storms transported mineral particles across the basin.
• Satellite observations documented trans-Pacific aerosol plumes.
• Chlorophyll measurements indicated productive plankton pastures.

The alignment was striking: sustained background mineral delivery from Asia combined with episodic volcanic pulses.

Pink salmon, with their fixed two-year life cycle, responded first and most dramatically.

Chum and sockeye — which spend multiple years at sea — are now showing delayed, integrated responses consistent with improved early marine survival.

This is precisely what our ocean pasture ecological theory predicts.

The Early Marine Bottleneck

For all salmon species, the most vulnerable period of life occurs in the first months at sea.

Small juveniles must:

• Find sufficient food,
• Grow rapidly,
• Avoid predators,
• Accumulate energy reserves before winter.

When plankton pastures are rich, survival rates increase sharply. Faster growth reduces predation risk and improves overwinter resilience.

When pastures are poor, mortality soars — and no amount of harvest restriction can compensate.

Understanding this early marine bottleneck is essential. It shifts our focus from managing only the fish to understanding and maintaining the ecosystem that feeds them.

The Declining Dust Problem

Here is the uncomfortable truth: natural mineral dust supply has changed over the past several decades.

The greening of Asian dust bowsl, altered wind regimes, damming of major rivers, and shifts in desert dynamics have modified the delivery of mineral particles to the North Pacific.

Volcanic eruptions still occur — but episodically.

Asian dust still travels, but it is interannually variable.

The long-term background nutrient subsidy that historically supported abundant salmon may no longer be sufficient to sustain peak productivity in today’s ocean conditions.

In other words, Mother Nature’s nutrient cycle is not as robust as it once was.

Helping Nature Help Herself

Nature-based mineral replenishment is not about overriding natural systems. It is about restoring a disrupted nutrient pathway.

In 2012, a carefully designed mineral addition to depleted Gulf of Alaska waters coincided with a record pink salmon return the following year.

That event demonstrated a powerful principle:

The ocean still remembers how to respond.

The plankton are ready.
The food web is ready.
The fish are ready.

The missing ingredient is often tiny amounts of iron, and we can remedy that!

There is terrific support for replenishing the ocean dust in new reportsin the scientific literature.

The Breakthrough 2025 Paper: Direct Evidence for Dust-Salmon Link

The most significant new scientific evidence supporting the blog’s thesis:

“Iron fertilization from Asian dust drives tertiary-level productivity of Pacific salmon” Published 2025 in Progress in Oceanography

Key Findings

• Tests the “extended iron hypothesis” — that iron fertilization drives not just primary production but tertiary-level productivity (fish stocks)
• Used both paleorecords (2,200 years of sediment cores from Karluk Lake, Kodiak Island) and modern time series data
• Correlated Karluk sockeye salmon abundance with climatic variables describing Asian dust flux, trans-Pacific transport, and deposition in the Gulf of Alaska
• Found that for approximately 2,200 years, the productivity of this salmon stock has been driven by Asian dust supply
• Modern observational data provide “more direct support for the linkage between dust-iron input, primary production, and salmon abundance”
• Concludes that “iron from Asian dust drives primary through to sockeye salmon productivity via bottom-up food-web control”

Significance

This is the first rigorous, multi-millennial-scale demonstration that Asian dust iron fertilization drives not just phytoplankton blooms but actual fish population dynamics. It moves the hypothesis from “plausible correlation” to “demonstrated mechanism” spanning over two millennia.

Economic and Ecological Dividends

Restoring mineral balance to ocean pastures offers multiple benefits:

• Increased salmon abundance and stability
• Stronger fishing economies
• Reduced allocation conflict
• Enhanced natural carbon uptake
• Greater resilience to climate variability

This is not a subsidy program. It is an investment in productivity.

Healthy pastures generate wealth organically — through fish, through ecosystem services, through community resilience.

A Responsible Path Forward

The path ahead must be grounded in science and transparency.

We are currently assembling:

• Basin-scale dust indices using atmospheric reanalysis datasets
• Matched chlorophyll response analyses
• Lagged comparisons to salmon cohort survival and returns
• Independent validation from Russian and North American research institutions

The goal is not advocacy. The goal is clarity.

If mineral dust is indeed a primary ecological driver — as the evidence increasingly suggests — then it belongs at the center of fisheries management and ecosystem policy discussions.

A Simple Truth

The North Pacific does not thrive by accident.

It thrives when the nutrient engines of the planet — deserts and volcanoes — supply the trace elements that life requires.

When those engines slow, productivity declines.

When they surge, abundance returns.

We cannot control volcanoes.
We cannot command deserts.

But we can understand the systems they support — and, where appropriate, carefully assist in restoring balance.

When the dust blows, the salmon grow.

And when we help nature restore her dust, we restore far more than fish.
We restore possibility.