11 Apr 2016:
More Than 50 Percent of
Great Barrier Reef Affected By Bleaching
Record high ocean temperatures in the western Pacific have caused more than half of the Great Barrier Reef to undergo a mass coral bleaching event this year, according to a team of Australian scientists
conducting aerial surveys.
ARC Coral Reef Studies
An aerial shot of the Great Barrier Reef in early April.
Corals thrive in a narrow temperature range, and when waters warm above normal—as they have this year from climate change and a strong El Nino—the organisms expel their symbiotic algae, leaving them without a source of food and susceptible to disease. Scientists’ next step is studying the corals up close to determine how deep the bleaching is, said
Terry Hughes, a marine biologist at James Cook University and head of the Australian coral bleaching task force. “If the corals are severely bleached, then a lot will die,” Hughes said. “If they are lightly bleached, which is the case with a lot of reefs south of Townsville, then they’ll regain their color over the next couple of months and there won’t be much mortality.”
05 Apr 2016:
El Nino Prevents Phytoplankton
Growth, Endangering Marine Food Web
El Nino—the cyclical warming of the Pacific Ocean—has wreaked havoc on the world’s weather
for the past two years, from a record-breaking number of cyclones in the North Pacific to flooding in South America.
Satellite images of phytoplankton growth.
But scientists at NASA recently discovered
that the climate phenomenon also has a big impact on phytoplankton, the tiny oceanic organisms that serve as the base of the marine food chain. Normally, ocean currents drive cold, deep water to the surface near the equator, bringing with it a flood of nutrients that feed phytoplankton. El Nino’s mass of warm water stops this upwelling. The result is a marked drop in phytoplankton levels. “This decline echoes through many species,” said Stephanie Uz, an ocean scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland who led the study. “Small fish that feed on phytoplankton starve. This affects everything from penguin and iguana populations in the Galapagos to governments managing fisheries.”
31 Mar 2016:
A New, Multi-Colored Way To
Study Cell Regeneration in Zebrafish
Zebrafish have amazing healing capabilities—they can grow back missing limbs and patch an injured heart or spine—but scientists have long been in the dark as to how exactly this process works.
Chen-Hui Chen, Duke University
An engineered zebrafish with multi-colored skin.
Now, a team of scientists at Duke University engineered neurons to create a zebrafish with skin that fluoresces in thousands of colors
in order to visually illustrate how cells regenerate after injury. They found there are three steps to the process: skin cells from neighboring body parts migrate in to cover the new tissue, surviving cells grow in size, and new cells are created. “It is like you have given each cell an individual barcode,” said
Chen-Hui Chen, a postdoctoral fellow at Duke and lead author on the study. “You can precisely see how individual cells collectively behave during regeneration.”
Interview: How Ocean Noise
Wreaks Havoc on Marine Life
Bowing to public pressure, the Obama administration recently reversed an earlier decision to allow oil drilling off the U.S. East Coast. But the five-year moratorium on drilling does not prohibit exploratory seismic air gun surveys
used to locate oil and gas reserves under the seabed, and those surveys are expected to be authorized this spring. Cornell University marine bioacoustics expert Christopher Clark says the testing, which can go on for weeks at a time, will only add to the rising din in the oceans. “Imagine that every 10 seconds there is an explosion that is rattling grandma’s china out of the cupboard,” he says, “and it is falling on the floor.” In an interview with Yale Environment 360
, Clark explains how noise, most of it from ship traffic, severely disrupts marine life, especially among whales. But the good news, he says, is that technologies are being developed to drastically reduce the noise from ships and geological surveying.
Read the interview.
24 Mar 2016:
A Fish With a Pelvis: Another
Clue Into Our Sea-to-Land Evolution
Biologists have long wondered exactly how fish emerged from the sea and transitioned into vertebrates that could walk on land. To date, most of the information on that shift has come from fossils,
A waterfall-climbing fish.
but scientists reported Thursday they have found that a species of fish located only deep in the caves of Thailand walks the same way land vertebrates do
. The blind waterfall-climbing fish, Cryptotora thamicola
, first discovered in 1985, has skeletal features similar to a salamander—including a fully formed pelvis—that enable them to climb up rock walls and feed on microbes and organic matter as water comes crashing down on them, the researchers wrote in Nature Scientific Reports
. “Functionally, it makes perfect sense, but to see it in a fish is incredibly wild,” said
Brooke Flammang, an expert on biomechanics at the New Jersey Institute of Technology and lead author of the study. The discovery could help more fully explain how life evolved from the sea to land.
23 Mar 2016:
Microbes Are Likely Speeding
Up the Melting of the Glaciers
As if soaring global temperatures weren’t bad enough, scientists reported this week that microbes are also speeding up the melting of Arctic ice.
National Parks Service
A pool of meltwater on the Root Glacier in Alaska.
The problem lies in cryoconite, the soil-like composite of dust, industrial soot and photosynthetic bacteria that darkens the surface of ice and causes it to melt, scientists from Aberystwyth University in Wales said. As it melts, ice leaves behind small water-filled holes full of bacteria. The sun-loving microbes then shape the pockmarks’ depth and size to get more light exposure, in turn melting the ice even more—a process previously unaccounted for in global climate change models. "It's only recently that we've begun to understand that these cryoconite holes are dynamic, changing in size and shape,” said
biologist Arwyn Edwards, who led the study. "In the long term, this contributes to the loss of glacier habitats, and the unique microbial biodiversity living on them."
22 Mar 2016:
Old Photos Used to Study
The Fate of a Swedish Seabird Colony
Nearly 100 years of old tourist photos got a second life recently when researchers used them to reconstruct the rise and fall
of a colony of seabirds on the Swedish island of Stora Karlsö. The island, designated a nature preserve in 1880 and a popular tourist destination since the 1920s, hosts a large population of common guillemots, one of the biggest species of auks. Ecologists Jonas Hentati-Sundberg and Olof Olsson of Stockholm University spent five years collecting images of the island from archives, museums, and island visitors in order to count guillemot numbers decade-to-decade. They found that the colony declined in the 1960s and 70s, when contaminants like DDT and PCB were prevalent, but has since rebounded to historically high numbers today, possibly because of an increase in the numbers of forage fish consumed by guillemots. “The population is currently increasing at an unprecedented rate
of about 5 percent annually," said Hentati-Sundberg. "This is interesting in that many common guillemot populations are decreasing worldwide."
15 Mar 2016:
Obama Administration Pulls
Proposal to Drill in the Atlantic Ocean
The Obama administration withdrew its proposal to open up offshore oil and gas drilling in the Atlantic Ocean on Tuesday.
Offshore drilling rigs in the Gulf of Mexico.
The decision blocks drilling in the region until 2022 and comes after an outpouring of opposition
to the plan from environmental groups and mid-Atlantic coastal communities and businesses concerned about a possible spill like Deepwater Horizon in the Gulf of Mexico five years ago. “Public pressure forced the administration to reverse course on Atlantic drilling," May Boeve, executive director of the environmental group 350.org, said in a statement. “We will continue to make the case that any new drilling is a stain on the president’s climate legacy and incompatible with the goals he committed to at the climate talks in Paris.”
14 Mar 2016:
Sea Level Rise Could Put
13.1 Million Americans At Risk of Flooding
Climate change and sea level rise could put 13.1 million Americans at risk of flooding by 2100, according to a new study
in the journal Nature Climate Change
Flooding in Davie, Florida
Nearly half of the at-risk population resides in Florida, and 70 percent in the southeastern United States. Unlike previous assessments that looked only at sea level rise, the study examines both climate and population projections for all 319 coastal U.S. counties over the next century. Three feet of sea level rise puts 4.2 million Americans at risk. Six feet—the high end of estimates by the National Oceanic and Atmospheric Administration—puts 13.1 million at risk. “The impact projections are up to three times larger than current estimates, which significantly underestimate the effect of sea level rise in the United States,” said
Mathew Hauer, lead author of the study and a demographer at the University of Georgia.
01 Mar 2016:
Despite El Nino, California Has Dry February As Drought Continues
El Nino failed to deliver much needed rain to California in February, dashing hopes that the climatic phenomenon could help end the state’s crippling four-year, multi-billion-dollar drought.
Ninety-four percent of California is in drought.
Downtown Los Angeles received only .79 inches of rain last month, when it typically gets 3.8 inches. The Bay Area got similarly low totals. "From past six strong El Ninos, we have generally seen above normal rainfall,” said
Robbie Munroe, a meteorologist for the National Weather Service. “But since October 1 we've only seen five inches of rain so far (across Southern California). We were certainly expecting a lot more." Meteorologists say a series of forecasted storms in early March could help, but with El Nino reportedly weakening and about 94 percent of California still in some form of drought, things aren’t looking good for the region.
24 Feb 2016:
Extended Bleaching Events
Are Killing Corals As Oceans Warm
Rising ocean temperatures are intensifying the die-off of corals around the planet, according to U.S. government scientists. “We are currently experiencing
Bleached coral at the Great Barrier Reef
the longest global coral-bleaching event ever observed,” said Mark Eakin
, head of Coral Reef Watch at the National Oceanic and Atmospheric Administration. Bleaching occurs when corals respond to environmental hazards, such as high ocean temperatures, by expelling the symbiotic algae they need to provide them with sustenance. Eakin predicted that the latest extended bleaching event, which started in 2014, will likely last well into next year, at which time about 60 percent of corals worldwide may be affected. Eakin compares the continuous pressure that reefs have been under in recent years to a boxing bout. “What used to be a one-round fight is turning into a two- and three-round fight,” he says.
05 Feb 2016:
Rising Temperatures Skewing
Gender Balance of Sea Turtles, Study Says
Rising global temperatures may be skewing the gender makeup of marine turtles, according to
new research from Florida State University
Loggerhead sea turtle
. The gender of marine hatchlings is influenced by the temperature of the sands in which they incubate, with warmer temperatures producing more females. “It's worrying that you could have an extreme skew in gender one way," said Mariana Fuentes, an assistant professor of oceanography at FSU. "Any changes in population structure can have real repercussions.” The scientists examined 25 years worth of data for 21 loggerhead turtle nesting beaches along the Brazilian coast, but the results are pertinent to other regions since temperature-dependent sex determination affects all turtles.
01 Feb 2016:
Lab-raised Caribbean Coral
Grown in the Wild for the First Time
Caribbean coral colonies bred in a lab, using in-vitro fertilization, have for the first time been raised to sexual maturity in their
natural marine habitat, according to findings published in the Bulletin of Marine Science
. Offspring of endangered elkhorn coral were reared from gametes collected in the field and successfully reattached to a reef a year later, where they have grown in size considerably
according to researchers from SECORE International
. Over the past four decades, an estimated 80 percent of all Caribbean corals have disappeared. The elkhorn coral’s decline is so severe that it was the first coral species to be listed as threatened under the U.S. Endangered Species Act in 2006. Due to its large size, branching shape, and preference for shallow waters, the coral is particularly effective at protecting shorelines from incoming storms, as well as providing a critical habitat for many reef organisms. Scientists hope this success will be an important step in helping restore endangered reefs
19 Jan 2016:
Ocean Absorption of Manmade
Heat Doubles Since 1997, Study Says
The amount of manmade heat absorbed by the world’s oceans has doubled since 1997, according to a study
Carbon dioxide in the atmosphere
released yesterday in the journal Nature Climate Change
. Scientists have long known that the oceans absorb more than 90 percent of manmade heat, but the study’s figures give a new and more accurate accounting for that process over a period of 150 years. According to the study, the oceans absorbed 150 zettajoules of energy between 1865 and 1997 — and an additional 150 zettajoules in just the past 18 years. “The changes we’re talking about, they are really, really big numbers,” said co-author Paul Durack, an oceanographer at the Lawrence Livermore National Lab in California. “They are nonhuman numbers.” Put in perspective, the amount of energy absorbed by the oceans since 1997 is the equivalent to a Hiroshima-sized bomb
being exploded every second for 75 years.
15 Jan 2016:
Northeast U.S. Waters Warming
Faster than Previously Thought, NOAA says
The ocean waters off the Northeastern United States may get even warmer, and this warming may occur twice as quickly as previously thought,
according to a new study
The Gulf of Maine is warming rapidly
by researchers for the National Oceanic and Atmospheric Administration. The findings, based on four global climate models, suggest that ocean temperatures in that region will rise three times faster than the global average. “Prior climate change projections for the region may be far too conservative,” said Vincent Saba, a NOAA fisheries scientist and lead author of the study. The Gulf of Maine has warmed faster than nearly 100 percent of the world’s oceans, likely due to a northerly shift in the Gulf Stream. Scientists have been studying the warming’s impact on the area’s marine ecosystem.
14 Jan 2016:
Europe’s Remaining Orcas
Threatened by Banned Toxins, Study Finds
Orcas and other dolphins living in European waters are facing a severe threat from lingering toxic chemicals that have been banned for decades,
Two orcas ply the waters
according to a study led by the Zoological Society of London and published in the journal Scientific Reports
. The research, which was based on long-term studies of more than 1,000 biopsied whales, dolphins, and porpoises in European waters, found that the blubber of these cetaceans contain some of the highest concentrations of polychlorinated biphenyls (PCBs) in the world. Without much stronger restrictions, "PCBs will continue to drive population declines or suppress population recovery in Europe for many decades to come," the study’s authors wrote. PCBs are a group of man-made chemicals previously used in the manufacture of electrical equipment, flame-retardants, and paints.
08 Jan 2016:
Study suggests most nitrogen
found in oceans comes from natural sources
The world’s oceans are less affected by human activities then previously suggested by atmospheric models when it comes to increased
Graph of various nitrogen sources found in oceans
nitrogen levels, according to a new study
published in Proceedings of the National Academy of Sciences
. The majority of nitrogen found in the oceans comes from the oceans themselves instead of human pollution blown off shore, which contradicts most models, the researchers say. That’s both good news and bad news. On the plus side, “People may not be polluting the ocean as much as we thought,” says Meredith Hastings, associate professor at Brown University, one of the study’s co-authors. Excess nitrogen can throw aquatic ecosystems out of balance and lead to large algal blooms that can be deadly for sea creatures. However, nitrogen also stimulates the growth of phytoplankton, which increases the oceans’ ability to absorb carbon dioxide from the atmosphere, thus mitigating carbon emissions to some extent.
18 Dec 2015:
Marshes Likely More Resilient
To Sea Level Rise Than Thought, Study Says
Marshes may be more resilient to climate change and associated rises in sea level than previously thought, according to recent research
An aerial view of Venice showing elevation by color
published in the Proceedings of the National Academy of Sciences.
The study shows that as levels of atmospheric carbon dioxide increase, more CO2 gets taken in by marsh plants. This spurs higher rates of photosynthesis and plant growth, causing marsh plants to trap more sediment above ground and generate more organic soil below ground, the researchers explain. The process can increase the rate of soil accretion nearly enough to allow marshes to keep up with rising sea levels. In fact, the researchers say, it may increase a marsh's threshold for water inundation by up to 60 percent. "Essentially, we found it's a self-rising mechanism marshes use to build themselves up," said Marco Marani, a researcher at Duke University who helped conduct the study.
14 Dec 2015:
Accelerating Rock Weathering
Could Help Reduce Atmospheric CO2 Levels
Speeding up the naturally occurring process of weathering rocks to draw carbon dioxide out of the atmosphere could help to
Weathered limestone cliffs in Yorkshire, England
stabilize the climate and avert ocean acidification caused by greenhouse gas emissions, according to
research published in the journal Nature Climate Change
. As rainwater and other environmental conditions naturally break down rocks on the earth's surface, carbon dioxide is drawn from the atmosphere. The process converts CO2 to bicarbonate, a mineral that chemically binds CO2 and is washed away through rivers to the oceans. By modeling the large-scale effects of weathering — which is driven largely by precipitation, vegetation, and soil microbes — the researchers found methods for accelerating this CO2-removal system. Such a strategy could significantly counteract anthropogenic fossil fuel emissions, they say, slowing ocean acidification and protecting delicate ocean ecosystems such as coral reefs.
13 Nov 2015:
Sharks Will Likely Be Less
Effective Hunters With Climate Change
Sharks will likely become much smaller and less aggressive hunters under the rising CO2 levels and warming oceans associated
Port Jackson sharks are bottom-dwellers.
with climate change, according to a study published in Scientific Reports
by University of Adelaide researchers. In large-tank laboratory experiments with Port Jackson sharks — a bottom-feeding variety that primarily relies on smell to find food — the researchers found that the combination of warmer water and high CO2 increased the sharks' energy requirements and reduced their metabolic efficiency. Elevated CO2 levels also dulled the sharks' sense of smell to the point that they were unable to locate prey — a finding confirmed in previous CO2/olfaction studies. Together, these effects led to dramatic reductions in the sharks' growth rates. "With a reduced ability to hunt, sharks will no longer be able to exert the same top-down control over the marine food webs, which is essential for maintaining healthy ocean ecosystems," said lead researcher Ivan Nagelkerken.
04 Nov 2015:
New York State Warns
To Prepare for up to 6 Feet of Sea Level Rise
New York State is telling developers and homeowners in New York City and coastal towns that they should prepare for up to 75 inches of sea level rise
by 2100. The sea level rise projections, based on recent scientific studies by NASA and Columbia University, are part of the New York Community Risk and Resiliency Act passed after the devastation caused by Hurricane Sandy in 2012. The state says it is creating new sea level rise regulations
requiring coastal planners, developers, and builders to expect seas that could rise up to six feet and to build more resilient homes and other structures. New York officials said 500,000 people live in areas that lie less than six feet above the mean high tide line in the state. The studies took into account increased melting of ice sheets and glaciers in Greenland and Antarctica.
26 Oct 2015:
Major Clue Emerges in Mystery
Of Right Whale Deaths, Researchers Say
Endangered right whales
, especially young calves of the southern population, have been having a hard time
in recent years, and
Southern right whale and calf near Peninsula Valdes
scientists haven't been able to determine why. For example, the average number of right whale deaths per year at Peninsula Valdes, a breeding ground off central Argentina's Atlantic coast, jumped more than 10-fold from 2005 to 2014 — from fewer than six per year to 65 per year, researchers say. Roughly 90 percent of the deaths were calves fewer than three months old. Now researchers have closed in on a suspect: blooms of a type of algae known as Pseudonitschia
, which produce harmful neurotoxins, the researchers write in the journal Marine Mammal Science
. Scientists from the United States and Argentina found that the number of whale deaths at the peninsula closely tracked the concentrations of the toxic algae, offering strong circumstantial evidence that the algal blooms are likely behind the whale deaths.
13 Oct 2015:
Antarctic Ice Shelves Face
Major Threat If CO2 Emissions Keep Rising
A new study says that many of Antarctica’s floating ice shelves — which play a key role in holding back vast amounts of land-based ice — could become highly unstable
later this century if greenhouse gas emissions are not sharply reduced. An international team of researchers, reporting in Nature Geoscience
, said that surface melting of Antarctica’s ice shelves could reach the point where many could disintegrate. Such surface melting has already led to the collapse of numerous ice shelves along the rapidly warming Antarctic Peninsula. The study said that surface melting of the continent’s ice sheets would double by 2050
under both intermediate- and high-emissions scenarios. After that, the fate of the ice shelves diverges sharply depending on emissions levels, with a high-emissions scenario leading to surface melting equaling or exceeding intensities associated with ice shelf collapse. Loss of the ice shelves could lead to major increases in sea level as inland glaciers flow to the sea, scientists say.
05 Oct 2015:
Icelandic Seafood Giant
May Be Involved in Endangered Whale Hunt
Iceland’s controversial annual hunt of fin whales — classified as "endangered" by the International Union for Conservation
of Nature — ended with a catch of 155 fin whales, the largest slaughter since the 1986 moratorium on commercial whaling, reports the London-based advocacy group Environmental Investigation Agency (EIA). The EIA and the Animal Welfare Institute obtained evidence
revealing the ongoing involvement of international seafood giant HB Grandi — a Reykjavík-based company with an annual income of roughly $230 million (as of 2011) — in the whaling business, despite its claims to the contrary. HB Grandi is Iceland’s largest seafood company and its CEO has repeatedly insisted that the company “is not involved in whaling and never has been.” Despite the international moratorium, Iceland recently has allowed commercial whaling and has shipped whale products to Japan.
01 Oct 2015:
International Space Station
Gives Glimpse of China's Aquaculture Sector
A slew of grid-patterned fish farms line the coast of Liaoning Province in northeast China, as shown in this photograph
Aquaculture in China's Liaoning Province
an astronaut aboard the International Space Station. The aquaculture operations have been built out from the highly agricultural coast to a distance of roughly 4 miles. Liaoning Province ranks sixth in China in terms of aquaculture production, and this group of fish farms, which face the Yellow Sea, is the largest set constructed along the province's coastline. The fish farm basins are built on shallow seabeds, mudflats, and bays. Outer barriers protect the basins from winter storms and large waves generated by passing ships. Most aquaculture products are purchased live in China, with less than 5 percent being killed and processed for selling in local or foreign markets, the U.N. Food and Agriculture Organization (FAO), says. Shellfish, a traditional marine food source, still dominates China's marine production, according to the FAO's Fisheries and Aquaculture Department, accounting for 77 percent of the market.
24 Sep 2015:
Nearly Half of U.S. Seafood
Is Wasted Annually, New Study Shows
As much as 47 percent of the edible U.S. seafood supply is wasted each year
, with more than half of that waste coming
Maine Avenue Fish Market in Washington, D.C.
at the consumer level as people throw away spoiled or uneaten seafood at home, according to a new study. Researchers from the Johns Hopkins Center for a Livable Future estimated the edible U.S. seafood supply at 4.7 billion pounds a year, and said that 2.3 billion pounds of that are wasted. The study, published in the Journal Global Environmental Change
, said that 573 million pounds are lost annually as commercial fisherman catch and discard the wrong species. Roughly 330 million pounds are lost during distribution and retail, and 1.3 billion pounds are lost at the consumer level. The researchers recommended a number of changes to reduce the waste, including stricter limits on by-catch by commercial fishermen and efforts to encourage consumers to purchase frozen seafood.
22 Sep 2015:
Antarctic Seafloor Life Is
Locking Away a Lot of Carbon, Study Says
The loss of sea ice over Antarctic waters has caused certain forms of life to flourish on the seafloor, and those underwater communities
An Antarctic icefish swimming over bryozoans
are acting as important and unexpected carbon sinks, according to research published in the journal Current Biology
. Based on studies of West Antarctic bryozoans — aquatic invertebrates sometimes referred to as "moss animals" — researchers have found that those and other seafloor organisms could play important roles in accumulating and burying carbon, removing it from the atmosphere for an extremely long time. The researchers calculate that growth of the bryozoans has nearly doubled over the past 20 years, with the animals taking in more than 200,000 tons of carbon per year since the 1980s. Accounting for other undersea species, the researchers suggest that roughly 3 million tons of carbon are sequestered each year, equivalent to nearly 200 square miles of tropical rainforest.
21 Sep 2015:
Rising Seas and More Intense
Storms Likely to Cause Major Flooding Spike
Rising seas and increasingly frequent and intense storms along the U.S. Atlantic and Gulf coasts could interact to produce alarming
Sea temperature increases along the Atlantic and Gulf coasts
spikes in the extent and duration of floods, according to a study published in Nature Climate Change
. The study projects that coastal flooding could possibly shoot up several hundred-fold by 2100, from the Northeast to Texas. Even the study's most conservative calculations, based on greatly reduced greenhouse gas emissions over the next 85 years, suggest a 4- to 75-fold increase in the the combined heights and durations of expected floods. Over the past century, the East Coast has experienced sea level rise far beyond the 8-inch global average — up to a foot in much of the Mid-Atlantic and Northeast, including New York City. Most projections call for a further 2- to 4-foot rise by 2100, and some estimates go as high as 6 feet. At the same time, other studies suggest that in the future the largest North Atlantic storms may become more intense because warmer waters contain more energy.
08 Sep 2015:
NASA Facilities at Risk
From Projected Sea Level Increases
Many of NASA’s key sites for launching spacecraft and carrying out research will be threatened by even moderate increases in sea level
Sea level rise near Johnson Space Center
the U.S. space agency reports. NASA says that half to two-thirds of its laboratories, launch pads, airfields, testing facilities, data centers and other infrastructure are situated at less than 16 feet (5 meters) above sea level. The agency released a handful of maps showing how even a one-foot rise in sea level would impact the operations of major sites such as the Kennedy Space Center in Florida, the Johnson Space Center in Texas, and the Langley Research Center in Virginia. Conservative projections say global sea level could increase by 5 inches by 2050, and numerous experts on climate change and sea level rise say that the world’s oceans could rise by 3 to 6 feet this century if emissions are not brought under control.
In Booming Aquaculture Industry,
A Move to Plant-Based Food for Fish
As the aquaculture industry continues to rapidly expand, with production more than doubling in the past 15 years, fishing pressure
A worker feeds trout.
has grown on the anchovies, sardines, and other species used to make feeds for farmed fish. Now, however, researchers are rapidly developing nutritious plant-based food that can put the aquaculture sector on a more sustainable path. Using protein-rich legumes such as soybeans and combining them with various oil-rich supplements, scientists say they are steadily moving toward all-vegetarian diets for aquaculture fish. “I was told by many [people] that fish require fishmeal because that’s what they eat in the natural world,” says one leading researcher. “But that’s just wrong.”