Saving Seafood

Warming water has varied impact on salmon populations

October 8, 2025 — Wild salmon are super weird for a variety of reasons, including response to warming climate conditions, says fisheries researcher Peter Westley of the University of Alaska Fairbanks.

“Salmon have really evolved in places with changing conditions, including volcanoes blowing up, glaciers melting and making really good salmon habitat,” Westley said on Wednesday, Sept. 24, in a webinar from his office on the Fairbanks campus. “Salmon are experiencing the front lines of (environmental) changes. Trends across the globe since 1991, the rate of warming is much, much faster in the Arctic. Salmon are experiencing warming and rapid change of warming.”

To maintain healthy salmon populations, the fish need cool, complex, connected, clean habitat, said Westley, an associate professor and Wakefield chair of Fisheries and Ocean Sciences at UAF’s Department of Fisheries and Ocean Sciences.

Connectivity is important so that the salmon have the ability to move around, he said. It is also important to protect the processes important to the fish, like the way groundwater comes up to cool the water, and gravel has to come into the streams, he said.

“Salmon bury their offspring alive and leave them in the gravel for months on end, nine to 10 months under the gravel.  They are born in fresh water, and then they decide freshwater is not for them and migrate to the ocean, and then they come back,” he said. “They can fill up streams in very high density and go back to their natal streams. They fight their way back home, and their bodies decay and become nutrients for others, including bears. Salmon are weird, but also awesome.”

Read the full article at National Fisherman

Lobsters face serious risks as oceans heat up

October 6, 2025 — The Gulf of Maine is warming faster than almost every other ocean region on Earth. That single fact has scientists worried about the future of the American lobster, the backbone of a two billion dollar fishery.

Warming, acidification, and marine heatwaves are not just abstract trends here. They are daily realities, reshaping one of the most iconic species in New England waters.

Communities along the coast depend on lobsters not only for income but also for identity. A shift in lobster health could ripple far beyond science labs and touch entire economies.

To understand what lies ahead, researchers at William & Mary’s Batten School and the Virginia Institute of Marine Science (VIMS) have been testing how lobster embryos respond to future ocean conditions. The results point to temperature as the main danger.

Read the full article at Earth.com

Marine ‘superfertilizer’ is crucial for life in the ocean and on land, including humans

October 1, 2025 — Half the oxygen in your next breath did not come from trees on land. Scientists estimate that phytoplankton in the ocean make about half of the oxygen in the air in Earth’s atmosphere.

These microscopic drifters depend on nutrients that large whales move to the sunlit surface when they release nutrient rich waste.

Field research shows that marine mammals enhance primary productivity by concentrating nitrogen near the surface through flocculent fecal plumes.

Phytoplankton and oxygen

After decades of field work, Robert Kenney, an emeritus marine research scientist at the University of Rhode Island (URI), has traced how whales, prey, and currents shape each season. His perspective helps connect nutrients, food webs, and survival across years.

Phytoplankton are tiny photosynthetic organisms that turn sunlight and carbon dioxide into sugar and oxygen. Zooplankton are small animals that graze on them and feed fish, seabirds, and whales.

When nutrients are scarce near the surface, phytoplankton growth slows and the whole food web tightens. When nutrients pulse upward, growth accelerates and energy ripples through the system.

Whales often feed at depth and then return to the surface to rest, breathe, and digest. When they defecate near the surface, their waste carries nitrogen and iron that phytoplankton can use right away.

That burst of nutrients supports fast growth, which boosts food for krill and fish in the upper ocean. Many large whales filter this prey using baleen, flexible plates in their mouths that act like a sieve.

The loop continues when predators eat that prey and release nutrients again in shallow water. Over time, this recycling keeps productivity higher than it would be without whales.

Read the full article at Earth.com

Maine’s longer, hotter summers are reshaping our natural world

September 29, 2025 — When she looks at the Narraguagus River, Valerie Ouellet sees what others can’t: a thermal mosaic that explains why it’s one of the last places in America where wild Atlantic salmon come to spawn.

This 55-mile-long waterway in Downeast Maine is a hodgepodge of cold-water pockets hidden within the warmer river where adult salmon can find refuge from the state’s increasingly hot summers.

Atlantic salmon do their best growing and spawning in 68-degree water. Any higher and they stop eating; they lay fewer, smaller eggs. At 73 degrees, they swim erratically. If they don’t find cold water created by shade trees, spring-fed tributaries or groundwater seepage, some will die.

Ouellet is an ecologist with the Atlantic Salmon Federation and is part of a state and federal research team that has spent two years documenting the river’s temperature and flow to explore how close, how big and how cold these spots must be for salmon to survive.

Read the full article at Maine Public

Marine heatwave ‘blob’ returns in Pacific, rivaling past events in size and impact

September 26, 2025 — In 2013, scientists noticed a block of unusually warm water detected in the Pacific Ocean between the Gulf of Alaska and the Coast of Southern California. This was recognized by meteorologists as a basin-scale marine heatwave (MHW), often referred to as “the blob”. This water mass hung around from 2013-2016 before re-emerging again in July of 2019 (known as Blob 2.0) and lasting 20 months.

In May 2025, the blob reappeared.

Rachel Hager, a spokesperson for NOAA Fisheries, said this new MHW has grown “approximately the same size as the contiguous U.S.” She added it now ranks among the top three largest MHWs ever recorded in the northeast Pacific Ocean since monitoring began in 1982.

Read the full article at KATU 2

Human Impacts on Ocean Could Double or Triple by 2050, a New UC Santa Barbara Study Warns

September 26, 2025 — By 2050, the combined impacts of climate change and human activity on the ocean could be two to three times greater than they are today. Without urgent efforts to reduce these threats, a new study from the National Center for Ecological Analysis and Synthesis—an independent research affiliate of the University of California, Santa Barbara—warns those forces could completely transform, or even wipe out, entire seascapes.

“Huge parts of the ocean will no longer be recognizable,” said Ben Halpern, lead author of the study and the research center’s director. “There are areas that will effectively just collapse and cease to be functioning as natural systems.”

For more than 20 years, Halpern, a marine ecologist, has been charting the ways humans are reshaping coastlines and oceans. In 2008, he produced one of the first global maps to pinpoint where marine ecosystems were under the most stress at the time. Since then, he said, he has emphasized the need to look ahead and project how global warming, along with other human-driven pressures, like industrial fishing, shipping, land-based agriculture and coastal development, are likely to intensify and converge.

Read the full article at Inside Climate News

Nations ratify world’s first treaty to protect marine biodiversity in international waters

September 22, 2025 — A major agreement to protect marine diversity in the high seas was struck Friday when Morocco became the 60th nation to sign on, paving the way for the treaty to take effect next year.

The High Seas Treaty is the first legal framework aimed at protecting biodiversity in international waters, those that lie beyond the jurisdiction of any single country. International waters account for nearly two-thirds of the ocean and nearly half of Earth’s surface and are vulnerable to threats including overfishing, climate change and deep-sea mining.

“The high seas are the world’s largest crime scene — they’re unmanaged, unenforced, and a regulatory legal structure is absolutely necessary,” said Johan Bergenas, senior vice president of oceans at the World Wildlife Fund.

Still, the pact’s strength is uncertain as some of the world’s biggest players — the U.S., China, Russia and Japan — have yet to ratify. The U.S. and China have signed, signaling intent to align with the treaty’s objectives without creating legal obligations, while Japan and Russia have been active in preparatory talks.

Ratification triggers a 120-day countdown for the treaty to take effect. But much more work remains to flesh out how it will be implemented, financed and enforced.

“You need bigger boats, more fuel, more training and a different regulatory system,” Bergenas said. “The treaty is foundational — now begins the hard work.”

Read the full article at PBS News

ALASKA: Drone photos suggest a 2014 marine heat wave is still stunting orca growth, reproduction in Alaska

September 16, 2025 — It’s well documented by now that the marine heatwave that hit the Pacific Ocean in 2014 had devastating effects on Alaska’s marine ecosystem and commercial fisheries.

Now, scientists are uncovering long-term impacts on Alaskan killer whales specifically – a harbinger as marine heat waves become more frequent and severe with climate change.

“We’ve learned that females that were growing during those heat wave years grew to smaller sizes,” said John Durban, a senior scientist with the New England Aquarium in Boston who has been studying killer whales in the Gulf of Alaska for two decades.

“If you’re smaller as a whale, it means you don’t have as much fasting endurance, you can’t store as much blubber,” Durban added. “So if you go through lean times, you’re less likely to bring a successful pregnancy to term.”

Durban has been partnering with the Alaska-based nonprofit North Gulf Oceanic Society to monitor several hundred resident, salmon-eating killer whales in the Gulf of Alaska. He flies drones over the water, which capture images of the whales from more than 100 feet in the air.

Those images allow researchers to measure how individual whales are developing over time.

The North Gulf Oceanic Society has been monitoring killer whales in the Gulf for more than four decades. Durban said that work became particularly important in the aftermath of the Exxon Valdez oil spill, which correlated with an “unprecedented” number of whale deaths among two pods that were exposed to the spill, according to NOAA.

Read the full article at Alaska Public Media

New England’s shrimp industry is struggling, with fishermen catching few in 2025

September 15, 2025 — There’s an effort underway to bring New England shrimp back to seafood customers — but fishermen have found few of the crustaceans, and the fishing industry that harvests them may face an even longer shutdown.

Fishermen have been under a moratorium on catching shrimp for more than a decade because of low population levels that scientists have attributed to climate change and warming oceans. The harvesters were allowed to catch a small number of shrimp this past winter as part of an industry-funded sampling and data collection program.

Read the full article at News Center Maine

An Annual Blast of Pacific Cold Water Did Not Occur, Alarming Scientists

September 12, 2025 — Each year between January and April, a blob of cold water rises from the depths of the Gulf of Panama to the surface, playing an essential role in supporting marine life in the region. But this year, it never arrived.

“It came as a surprise,” said Ralf Schiebel, a paleoceanographer at the Max Planck Institute for Chemistry who studies the region. “We’ve never seen something like this before.”

The blob is as much as 10 degrees Celsius colder than the surface water. In Fahrenheit terms, the water would be 18 degrees colder than the surface water. That cold water is also rich in nutrients from decomposing matter that falls to the ocean floor, providing food for local fisheries and wildlife.

Read the full article at The New York Times