Seafood is the world’s most highly traded food commodity, by value, and the product is hard to track from source to market. Reports of seafood mislabeling have increased over the past decade, but few studies have considered the overall environmental effects of this deceptive practice.

A study by Arizona State University, the 91̽�� and other institutions examined the impacts of seafood mislabeling on the marine environment, including population health, the effectiveness of fishery management, and marine habitats and ecosystems.

The , recently published in the Proceedings of the National Academy of Sciences, show that some 190,000 to 250,000 tons of mislabeled seafood are sold each year in the U.S., making up 3.4% to 4.3% of all the seafood consumed. Farmed Atlantic salmon, often labeled and sold as Pacific salmon or rainbow trout, is the second-most-consumed mislabeled seafood product in the U.S., just behind shrimp.

Co-author , an assistant professor in the 91̽��School of Marine and Environmental Affairs, helped to design a statistical analysis to compare the product on the label with the one that was actually consumed.

“It’s important to consider mislabeled consumption, rather than mislabeling rates, when thinking about the various biological and environmental impacts of mislabeling,” Jardine said.

“You can have a species that’s mislabeled the majority of the time, but if the consumption of that species is low, then the amount of the mislabeled product consumed is also low, and it may not be as big of a management concern.

“On the other hand, you can get products with low mislabeling rates and high consumption, meaning that a lot of the mislabeled product is being consumed. We find this is the case for giant tiger prawns being sold as white leg shrimp, and for Atlantic salmon being sold as Pacific salmon.”

The authors used the program that assesses about 85% of seafood consumed in the U.S. and offers consumer recommendations for more sustainable choices. The authors combined those scores with mislabeling and consumption rates to compare the population health and fishery management of the species actually consumed versus the one on the label.

Genetic techniques can tell whether a seafood product is being marketed as a similar, higher value species, a switch that can happen at many points in the supply chain.

The most widely-consumed mislabeled product is shrimp, the most popular seafood in America. Imported giant tiger prawns, that are in Seafood Watch’s “Avoid” category, can end up labeled as white leg shrimp, in the “Best” category.

Salmon came in second on the amount of mislabeled seafood consumed. Farmed Atlantic salmon, in the “Avoid” category, can end up labeled as Pacific salmon or rainbow trout, typically in the “Best” or “Good” category.

More generally, the study shows that false labeling tends to substitute a less sustainable product. Substituted seafood was 28% more likely to be imported from other countries, which often have weaker environmental laws than the ones covering the domestic seafood listed on the label.

“In the United States, we’re actually very good at managing our fisheries,” said lead author , an assistant professor at Arizona State University’s School of Sustainability. “We assess the stock so we know what’s out there. We set a catch limit. We have strong monitoring and enforcement capabilities to support fishers adhering to the limit. But many countries we import from do not have the same management capacity.”

In 86% of cases, substitutes for wild-caught species came from fisheries that performed worse in terms of population impacts — species abundance, fishing mortality, and bycatch and discards — than the species on the label. Mislabeling also tended to disguise bad management practices: 78% of the substituted seafood had lower fishery management effectiveness than the product listed on the label.

“The expected species is often really well managed,” Kroetz said.

Public attention has tended to focus on frequently mislabeled species even if Americans consume less of those products.

“There’s been a lot of media attention given to the mislabeling rates of a particular species, such as halibut and snapper,” Jardine said. “But a big-picture analysis shows that we should also focus on other species if we are concerned about the environmental impacts.”

The effects of seafood mislabeling are not just environmental, the authors write, but also economic and social, affecting seafood consumers and the sustainable fishing industry.

“If the seafood sustainability movement was better integrated with seafood mislabeling testing, rate estimation and regulatory tracing programs, we could provide the consumer with better information regarding the biological, social and economic implications of the products that they consume,” Jardine said.

The study was funded by the Paul M. Angell Family Foundation and Resources for the Future. The work was also supported by the National Socio-Environmental Synthesis Center in Annapolis, Maryland, with funding from the National Science Foundation.

Other co-authors are Patrick Lee, Katrina Chicojay Moore and Andrew Steinkruger at the Washington, D.C.-based nonprofit Resources for the Future; C. Josh Donlan and Gloria Luque at the Williamsburg, Virginia-based nonprofit Advanced Conservation Strategies; Jessica Gephart at American University; and Cassandra Cole at Harvard University.

For more information, contact Jardine at jardine@uw.edu or Kroetz at kailin.kroetz@asu.edu.

Adapted from an ASU . See also a from Advanced Conservation Strategies.

But new research is showing that climate change is expected to accelerate rates of crop loss due to the activity of another group of hungry creatures — insects. In a published Aug. 31 in the journal , a team led by scientists at the 91̽�� reports that insect activity in today’s temperate, crop-growing regions will rise along with temperatures. Researchers project that this activity, in turn, will boost worldwide losses of rice, corn and wheat by 10-25 percent for each degree Celsius that global mean surface temperatures rise. Just a 2-degree Celsius rise in surface temperatures will push the total losses of these three crops each year to approximately 213 million tons.

“We expect to see increasing crop losses due to insect activity for two basic reasons,” said co-lead and corresponding author , a 91̽��associate professor of oceanography. “First, warmer temperatures increase insect metabolic rates exponentially. Second, with the exception of the tropics, warmer temperatures will increase the reproductive rates of insects. You have more insects, and they’re eating more.”

In 2016, the United Nations estimated that at least 815 million people worldwide don’t get enough to eat. Corn, rice and wheat are staple crops for about 4 billion people, and account for about two-thirds of the food energy intake, the UN Food and Agriculture Organization.

“Global warming impacts on pest infestations will aggravate the problems of food insecurity and environmental damages from agriculture worldwide,” said co-author , a professor in the Department of Earth System Science at Stanford University and founding director of the Center on Food Security and the Environment. “Increased pesticide applications, the use of GMOs, and agronomic practices such as crop rotations will help control losses from insects. But it still appears that under virtually all climate change scenarios, pest populations will be the winners, particularly in highly productive temperate regions, causing real food prices to rise and food-insecure families to suffer.”

To investigate how insect herbivory on crops might affect our future, the team looked at decades of laboratory experiments of insect metabolic and reproductive rates, as well as ecological studies of insects in the wild. Unlike mammals, insects are ectothermic, which means that their body temperature tracks the temperature of their environment. Thus, the air temperature affects oxygen consumption, caloric requirements and other metabolic rates.

The past experiments that the team studied show conclusively that increases in temperature will accelerate insect metabolism, which boosts their appetites, at a predictable rate. In addition, increasing temperatures boost reproductive rates up to a point, and then those rates level off at temperature levels akin to what exist today in the tropics.

Deutsch and his colleagues found that the effects of temperature on insect metabolism and demographics were fairly consistent across insect species, including pest species such as aphids and corn borers. They folded these metabolic and reproductive effects into a model of insect population dynamics, and looked at how that model changed based on different climate change scenarios. Those scenarios incorporated information based on where corn, rice and wheat — the three largest staple crops in the world — are currently grown.

“Temperate regions are currently cooler than what’s optimal for most insects. But if temperatures rise, these insect populations will grow faster,” said co-author , a researcher at the University of Vermont’s College of Agriculture and Life Sciences and the Gund Institute for Environment. “They will also need to eat more, because rising temperatures increase insect metabolism. Together, that’s not good for crops.”

For a 2-degree Celsius rise in global mean surface temperatures, their model predicts that median losses in yield due to insect activity would be 31 percent for corn, 19 percent for rice and 46 percent for wheat. Under those conditions, total annual crop losses would reach 62, 92 and 59 million tons, respectively.

The researchers observed different loss rates due to the crops’ different growing regions, Deutsch said. For example, much of the world’s rice is grown in the tropics. Temperatures there are already at optimal conditions to maximize insect reproductive and metabolic rates. So, additional increases in temperature in the tropics would not boost insect activity to the same extent that they would in temperate regions – such as the United States’ “.”

The team notes that farmers and governments could try to lessen the impact of increased insect metabolism, such as shifting where crops are grown or trying to breed insect-resistant crops. But these alterations will take time and come with their own costs.

“I hope our results demonstrate the importance of collecting more data on how pests will impact crop losses in a warming world — because collectively, our choice now is not whether or not we will allow warming to occur, but how much warming we’re willing to tolerate,” said Deutsch.

Co-lead author is , director of Future Earth at the University of Colorado, Boulder. Additional co-authors are , a 91̽��research scientist in the Department of Atmospheric Sciences; , a 91̽��professor of atmospheric sciences; and , a 91̽��professor emeritus of biology. The research was funded by the National Science Foundation and the Gordon and Betty Moore Foundation.

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For more information, contact Deutsch at cdeutsch@uw.edu or +1 206-543-5189 and the 91̽�� News Office at +1 206-543-2580.

DOI: 10.1126/science.aat3466

Grant numbers: OCE-1419323, OCE-1458967, OCE-1542240, GBMF#3775

Research led by the 91̽�� looks at what climate change will mean for global yields of this crop. The results show that warmer temperatures by the end of this century will reduce yields throughout the world, confirming previous research. But the study also shows dramatic increases in the variability of corn yields from one year to the next and the likelihood of simultaneous low yields across multiple high-producing regions, which could lead to price hikes and global shortages.

The study was published the week of June 11 in the .

“Previous studies have often focused on just climate and plants, but here we look at climate, food and international markets,” said lead author , a 91̽��postdoctoral researcher in atmospheric sciences. “We find that as the planet warms, it becomes more likely for different countries to simultaneously experience major crop losses, which has big implications for food prices and food security.”

In the wake of a recent 91̽��study looking at the under climate change, this study addressed overall yields and price volatility of corn.

While most rice is used domestically, corn is traded on international markets. Four countries — U.S., Brazil, Argentina and the Ukraine — account for 87 percent of the global corn exports (China mostly produces for domestic use). Today the probability that all four exporters would have a bad year together, with yields at least 10 percent below normal, is virtually zero.

But results show that under 2 degrees Celsius warming, which is projected if we succeed in curbing greenhouse gas emissions, this risk increases to 7 percent. Under 4 degrees Celsius warming, which the world is on track to reach by the end of the century if current greenhouse gas emissions rates continue, there’s an 86 percent chance that all four maize-exporting countries would simultaneously suffer a bad year.

In other words, it suggests cases like the , which devastated crops there, will be more likely to coincide with bad years in other regions.

“Yield variability is important for determining food prices in international markets, which in turn has big implications for food security and the ability of poor consumers to buy food,” Tigchelaar said.

The study used global climate projections with maize growth models to confirm previous research showing that warmer temperatures will negatively affect corn crops.

“When people think about climate change and food, they often initially think about drought,” Tigchelaar said, “but it’s really extreme heat that’s very detrimental for crops. Part of that is because plants grown at a higher temperature demand more water, but it’s also that extreme heat itself negatively affects crucial stages in plant development, starting with the flowering stage and ending with the grain-filling stage.”

The results show that while warmer temperatures will severely decrease average maize yields in the southeastern U.S., Eastern Europe and sub-Saharan Africa, and will increase the variability in the U.S. and other exporting nations.

“Even with optimistic scenarios for reduced emissions of greenhouse gases, results show that the volatility in year-to-year maize production in the U.S. will double by the middle of this century, due to increasing average growing season temperature,” said co-author , a 91̽��professor of atmospheric sciences. “The same will be true in the other major maize-exporting countries. Climate change will cause unprecedented volatility in the price of maize, domestically and internationally.”

The study did not include precipitation changes, since those are harder to predict, and projections show that changes will be small compared to the natural changes in rainfall from one year to the next. It also assumed that temperature swings will stay the same as today, though some models project temperatures will become more variable under climate change.

“We took a conservative approach and assumed the ‘weather’ will be the same, only acting on top of an overall warmer climate,” Battisti said.

The findings support efforts to pursue new agricultural technology to ensure food security for a growing global population. The authors write that their results “underscore the urgency of investments in breeding for heat tolerance.”

The other co-authors are Rosamond Naylor at Stanford University and Deepak Ray at the University of Minnesota. The study was funded by the Tamaki Foundation.

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For more information, contact Tigchelaar at mtigch@uw.edu or Battisti at battisti@uw.edu.

But in low doses, hydrogen sulfide could greatly enhance plant growth, leading to a sharp increase in global food supplies and plentiful stock for biofuel production, new 91̽�� research shows.

“We found some very interesting things, including that at the very lowest levels plant health improves. But that’s not what we were looking for,” said , a 91̽��doctoral student in who led the research.

Dooley started off to examine the toxic effects of hydrogen sulfide on plants but mistakenly used only one-tenth the amount of the toxin he had intended. The results were so unbelievable that he repeated the experiment. Still unconvinced, he repeated it again – and again, and again. In fact, the results have been replicated so often that they are now “a near certainty,” he said.

“Everything else that’s ever been done on plants was looking at hydrogen sulfide in high concentrations,” he said.

The is published online April 17 in , a Public Library of Science journal.

At high concentrations – levels of 30 to 100 parts per million in water – hydrogen sulfide can be lethal to humans. At one part per million it emits a telltale rotten-egg smell. Dooley used a concentration of 1 part per billion or less to water seeds of peas, beans and wheat on a weekly basis. Treating the seeds less often reduced the effect, and watering more often typically killed them.

A time-lapse video shows how a seed of dwarf wheat treated with a low dose of hydrogen sulfide begins growing at an accelerated rate compared with an untreated seed.

With wheat, all the seeds germinated in one to two days instead of four or five, and with peas and beans the typical 40 percent rate of germination rose to 60 to 70 percent.

“They germinate faster and they produce roots and leaves faster. Basically what we’ve done is accelerate the entire plant process,” he said.

Crop yields nearly doubled, said Peter Ward, Dooley’s doctoral adviser, a 91̽��professor of biology and of Earth and space sciences and an authority on Earth’s mass extinctions.

Hydrogen sulfide, probably produced when sulfates in the oceans were decomposed by sulfur bacteria, is believed to have played a significant role in several extinction events, in particular the “Great Dying” at the end of the Permian period. Ward suggests that the rapid plant growth could be the result of genetic signaling passed down in the wake of mass extinctions.

At high concentrations, hydrogen sulfide killed small plants very easily while larger plants had a better chance at survival, he said, so it is likely that plants carry a defense mechanism that spurs their growth when they sense hydrogen sulfide.

“Mass extinctions kill a lot of stuff, but here’s a legacy that promotes life,” Ward said.

Dooley recently has applied hydrogen sulfide treatment to corn, carrots and soybeans with results that appear to be similar to earlier tests. But it is likely to be some time before he, and the general public, are comfortable with the level of testing to make sure there are no unforeseen consequences of treating food crops with hydrogen sulfide.

The most significant near-term promise, he believes, is in growing algae and other stock for biofuels. Plant lipids are the key to biofuel production, and preliminary tests show that the composition of lipids in hydrogen sulfide-treated plants is the same as in untreated plants, he said.

When plants grow to larger-than-normal size, they typically do not produce more cells but rather elongate their existing cells, Dooley said. However, in the treatment with hydrogen sulfide, he found that the cells actually got smaller and there were vastly more of them. That means the plants contain significantly more biomass for fuel production, he said.

“If you look at a slide of the cells under a microscope, anyone can understand it. It is that big of a difference,” he said.

Ward and Suven Nair, a 91̽��biology undergraduate, are coauthors of the PLOS ONE paper. The work was funded by the .

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 For more information, contact Dooley at fdd@uw.edu, or Ward at 206-543-2962 or ward.biology.uw@gmail.com.

The paper is available at