Chicken and salmon have equivalent—and surprisingly far-reaching—environmental impacts

Read the full story at Anthropocene Magazine.

Many people choose fish instead of meat to offset their environmental footprints. But if the choice is farmed salmon instead of chicken, then researchers have some unsettling results to share: the environmental impact of these two foods is about the same.

The reason for that is their feed, which is remarkably similar for chicken and salmon, and accounts for the majority of impacts—which are spread across land and sea for both animals.

New research reveals 12 ways aquaculture can benefit the environment

Read the full story from the University of Melbourne.

Aquaculture, or the farming of aquatic plants and animals, contributes to biodiversity and habitat loss in freshwater and marine ecosystems globally, but when used wisely, it can also be part of the solution, new research shows.

Lobsters versus right whales: The latest chapter in a long quest to make fishing more sustainable

Lobster fishing uses a lot of rope, and whales can die after becoming entangled in it. MyLoupe/Universal Images Group via Getty Images

by Blake Earle, Texas A&M University

Maine lobster fishermen received a Christmas gift from Congress at the end of 2022: A six-year delay on new federal regulations designed to protect critically endangered North Atlantic right whales.

The rules would have required lobstermen to create new seasonal nonfishing zones and further reduce their use of vertical ropes to retrieve lobster traps from the seafloor. Entanglement in fishing gear and collisions with many types of ships are the leading causes of right whale deaths.

Maine’s congressional delegation amended a federal spending bill to delay the new regulations until 2028 and called for more research on whale entanglements and ropeless fishing gear. Conservationists argue that the delay could drive North Atlantic right whales, which number about 340 today, to extinction.

This is the latest chapter in an ongoing and sometimes fraught debate over fishing gear and bycatch – unintentionally caught species that fishermen don’t want and can’t sell. My research as a maritime historian, focusing on disputes tied to industrial fishing, shows the profound impacts that particular fishing gear can have on marine species.

Disputes over fishing gear and bycatch have involved consumers, commercial fishermen, recreational anglers and environmentalists. With conservation pitted against economic livelihoods, emotions often run high. And these controversies aren’t resolved quickly, which bodes poorly for species on the brink.

Millions of tons wasted

Bycatch is difficult to measure. Estimates vary widely, but scientists have calculated that 10% to 40% of total yearly catches worldwide are species that weren’t targeted, including fish, whales, dolphins, turtles and seabirds.

According to the United Nations, global fishery harvests totaled 178 million tons in 2020. Even by the most conservative estimates, then, some 20 million tons are likely wasted annually. Advocacy focuses on high-profile species like sea turtles, dolphins and sharks, but the problem is much more pervasive. Recent studies of U.S. Atlantic fisheries indicate that flounder, herring and halibut are among the species most frequently landed as bycatch.

At the same time, global demand for fish is rising. From 1961 to 2019, world fish consumption grew by an average of 3% annually, and yearly per capita consumption increased from 22 pounds (10 kilograms) to 46 pounds (21 kilograms). Today, fish consumption is split evenly between aquaculture, or farmed fish, and wild-capture fisheries, where bycatch occurs.

Bycatch is a major global problem that kills fish, marine mammals, sea turtles and seabirds.

Dolphin-free tuna

Most wild-catch fishing takes place far from shore, so bycatch occurs out of the public spotlight. Sometimes, though, threats to charismatic species make news.

Logo approved by U.S. regulators in 2000 for tuna caught without targeting dolphins. NOAA

Perhaps the most prominent example is U.S. consumers’ campaign against the tuna fishing industry for killing dolphins. In the 1950s, tuna fishermen adopted the purse seine – a long, rectangular net that hangs vertically in the water. Boats encircled schools of fish with these nets, then cinched them at the top and bottom. Some nets extended hundreds of feet deep and more than a mile from end to end.

Purse seines often swept up dolphins that swam alongside tuna. Using a method called “setting on dolphins,” tuna fishermen would search for pods of dolphin feeding at the surface, which generally indicated that tuna were beneath them feeding as well. By the 1960s, it was estimated that nearly a quarter of a million dolphins were dying every year when they became trapped in nets and suffered traumatic injuries or suffocated.

When Congress held hearings in the early 1970s on a proposed ban on the capture of all species of whales, including dolphins, this practice sparked outrage. The New York Times accused the tuna industry of “wanton slaughter.” Millions of viewers watched televised documentaries with titles like “Last Day of the Dolphins?” and “Where Have All the Dolphins Gone?” Advocacy groups campaigned with slogans like “Would You Kill Flipper for a Tuna Sandwich?” and boycotted canned tuna.

Under pressure, major suppliers including StarKist, Chicken of the Sea and Bumble Bee pledged to use only tuna that was not caught using methods that endangered dolphins. In 1990, Congress passed legislation creating a label that identified canned tuna caught appropriately as “dolphin-safe.” Other measures banned tuna imports from countries with dolphin mortality rates higher than those in U.S. fisheries.

Trap doors for turtles

The spotlight next shifted to the U.S. Gulf Coast, where shrimp catches were skyrocketing thanks to gear like otter trawls – large conical nets towed through the water behind fishing boats. By some estimates, for every 1,000 pounds of fish that these nets gathered, less than 100 pounds was marketable shrimp. Other species – usually dead, dying or injured – were tossed overboard.

Environmentalists and recreational anglers accused the fishing industry of endangering popular sport fish, such as red drum and spotted trout. But sea turtles, which often were found in the same coastal waters as shrimp, became critics’ poster animal. A 1990 report from the National Research Council estimated that shrimping killed up to 55,000 Kemp’s ridley and loggerhead sea turtles yearly.

Federal regulators initially proposed voluntary use of turtle excluder devices, or TEDs – small trap doors in fishing nets that could allow captured turtles to swim free. In 1987, the National Oceanic and Atmospheric Administration published mandatory TED usage regulations, which went into effect in 1989 after several years of lawsuits, injunctions and state legal action.

Turtle excluder devices, or TEDs, direct sea turtles toward openings in shrimp nets that allow the turtles to escape.

Many fishermen argued that TEDs greatly reduced their shrimp catches and resisted the new regulations, sometimes agressively. Over time, however, shrimpers began working with federal regulators to develop and test TEDs that released turtles and retained shrimp more effectively. Today, sea turtles are still at risk, but there is wide agreement that modern TEDs effectively reduce turtle bycatch. Conservation organizations are working to increase their use worldwide.

Slow progress

Fishermen often are quick to rebut claims that their methods endanger other species. They typically assert that their fishing has little impact on the broader ecosystem and that new gear and practices will be too costly or ineffective against a minor problem.

Ultimately, public pressure – including lawsuits – can lead to regulation, especially when a potent symbol like dolphins, sea turtles or, perhaps, right whales, is threatened. The Maine lobster fishery has lost several sustainable certifications because of concerns about right whale entanglements.

But regulation isn’t enough. Reducing dolphin and sea turtle bycatch also required extensive engagement between regulators and fisheries to educate fishermen and develop and test gear. It’s not clear whether this will happen fast enough to save North Atlantic right whales.

Across broad swaths of the globe, including much of Africa and Asia, more than 3 billion people obtain from 20% to over 50% of the animal protein in their diets from aquatic sources. Rising demand for wild-caught fish is likely to increase bycatch. In my view, unintentional capture of any species – whether it’s a winsome spinner dolphin or a bottom-dwelling scavenger like the hagfish – harms the ocean’s ecological health and threatens communities that rely on the sea for sustenance.

Blake Earle, Assistant Professor of History, Texas A&M University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Suspected illegal fishing revealed by ships’ tracking data

Read the full story in Nature.

When fishing vessels hide their locations, they sometimes reveal a wealth of information. Gaps in tracking data can hint at illegal activity, finds a modelling study.

Tuna catch rates soared after creation of no-fishing zone in Hawaii

Read the full story in Nature.

Large no-fishing areas can drive the recovery of commercially valuable fish species, a study suggests. Ten years’ worth of fisheries data have shown that catch rates of two important types of tuna increased drastically in the vicinity of a marine protected area surrounding the northwestern Hawaiian islands.

Federal Fisheries Management: Overfishing Determinations Vary Across Regions, and Data Challenges Complicate Management Efforts

Download the document.

What GAO Found

GAO’s analysis of National Marine Fisheries Service (NMFS) data found that the number of fish stocks assessed for 2011 through 2020 varied by the six NMFS regional fisheries science centers and that many stocks were not assessed. For example, on average, the Southeast Science Center assessed about 10 percent of the 153 stocks it supported each year, while the Alaska Science Center assessed about 78 percent of its 64 stocks.

NMFS uses these assessments to support management, including determining whether a stock is in overfishing or is overfished. GAO found that the number of stocks in these statuses varied by science center and that many stocks had an unknown status (see fig. for overfishing information). Challenges inherent in collecting fisheries data, along with resource challenges, affected the availability and quality of the data. For example, trawl surveys, which are used to collect fisheries data, are challenging and costly to conduct over large geographic areas. These challenges were a key source of the variability in the number of stocks assessed and one of the reasons why many stocks may have unknown status.

Average Annual Number of Fish Stocks Experiencing Overfishing and Average Number with an Unknown Overfishing Status, by National Marine Fisheries Service (NMFS) Fisheries Science Centers for 2011 through 2020
Average Annual Number of Fish Stocks Experiencing Overfishing and Average Number with an Unknown Overfishing Status, by National Marine Fisheries Service (NMFS) Fisheries Science Centers for 2011 through 2020

Note: Some science centers are jointly responsible for assessing a fish stock. The averages do not total the amount noted in the report, due to rounding. A fish stock is a fish species or stock complex, which is a group of stocks similar enough to be managed as a single unit.

In reviewing NMFS’ stock assessment and status data, GAO identified issues with the Species Information System database that prevented conducting certain multiyear trend analyses. NMFS has not documented these structural limitations or developed general guidelines for how to complete such analyses. NMFS officials noted that such analyses can be useful for tracking changes in stock status, as well as the frequency with which individual fish stocks have been assessed over time. NMFS is working on two projects to improve the functionality of the database. The plans for these projects do not include key project management elements, such as written goals and timelines. Developing a plan that includes these elements could help ensure completion of the projects and help NMFS conduct additional analyses that could be used to support management measures to prevent overfishing and manage overfished stocks.

Why GAO Did This Study

Commercial and recreational marine fisheries are a critical part of our nation’s economy. These fisheries contributed $118 billion to the U.S. gross domestic product and supported 1.8 million jobs in 2019. NMFS and eight Regional Fishery Management Councils (Council) are responsible for managing about 460 fish stocks in federal waters. This includes minimizing the extent to which stocks experience overfishing or become overfished. Overfishing occurs when the number of fish caught is above a certain threshold; a stock becomes overfished when its population is deemed to be too low.

GAO was asked to review federal efforts to prevent overfishing and manage overfished stocks. Among other things, this report examines the number of stock assessments conducted from 2011 to 2020, along with the number and status of overfishing and overfished stocks during this period. GAO reviewed NMFS policies and documents; interviewed NMFS regions, Councils, and relevant stakeholders based on factors such as familiarity with different regions of the United States; and analyzed data from NMFS’ Species Information System database.


GAO is making two recommendations to NMFS on the structural limitations of the Species Information System database, including developing guidelines for conducting certain multiyear analyses, as well as incorporating leading practices into its database improvement plans. The agency agreed with GAO’s recommendations.

Recommendations for Executive Action

Agency AffectedRecommendationStatus
National Marine Fisheries ServiceThe Assistant Administrator for NMFS should develop written documentation of the structural limitations of the Species Information System database, as well as general guidelines on how to conduct the manual editing needed for multiyear trend analysis and reporting purposes. (Recommendation 1)When we confirm what actions the agency has taken in response to this recommendation, we will provide updated information.
National Marine Fisheries ServiceThe Assistant Administrator for NMFS should develop a written plan for executing the Species Information System database improvement projects, including the project goals, the procedures to be followed, a timeline for completion, and a schedule for providing status updates. (Recommendation 2)When we confirm what actions the agency has taken in response to this recommendation, we will provide updated information.

Understanding complex fluid dynamics could help advance sustainability of food systems

Read the full story from the University of Massachusetts Amherst.

A University of Massachusetts Amherst food scientist has been awarded two USDA National Institute of Food and Agriculture grants to pursue research designed to benefit the environment and human health in different ways.

In one project, funded with a three-year grant totaling $630,000, assistant professor Jiakai Lu aims to reduce the use of conventional agricultural pesticides by developing an eco-friendly drift reduction agent using essential oils derived from food waste, such as orange peel and culinary herbs. 

In the other project, Lu was awarded a two-year, $270,000 seed grant to work on developing a potentially scalable processing technology aimed for plant-based seafood that better mimics the texture of fish meat, a significant challenge in the effort to create a sustainable and environmentally friendly solution to overfishing and related pollution.

SIU researchers seek to use invasive copi as baby food for farm-raised yellow perch

Read the full story from Southern Illinois University.

Caring for a human baby is hard. Two researchers at Southern Illinois University Carbondale will tell you raising “infant” fish may be even more challenging.

Karolina Kwasek and Michal Wojno are trying to find better ways to hatch and successfully raise yellow perch to the juvenile stage in aquaculture. A married couple with a baby of their own, they use research methods that combine low-tech hatchery equipment, easily copied by professional fish farmers, with creating a new feed that uses the invasive species copi as a protein source.

The research will last through 2023. Success would mean greatly increasing yellow perch’s survival rates at indoor hatcheries, leading to business expansion for more aquacultural ventures and better prices for consumers.

Alaska’s herring row

Read the full story from the Food & Environment Reporting Network.

The tiny fish is central to Tlingit culture and to sustainable ecosystems. Overfishing threatens both.

Connecticut’s shellfish population gets a boost with state’s first restoration guide

Read the full story from Pew.

The Connecticut Shellfish Restoration Guide provides science-based, well-tested techniques to help oyster farmers, state and local officials, academic institutions, and others involved in restoration efforts increase shellfish and fish populations, improve water quality, strengthen coastal habitats, and stabilize shorelines.

One component of the guide is the CT Shellfish Restoration Map Viewer, an online, interactive mapping tool released in 2021. Previously, without a central, comprehensive habitat map to work from, oyster restoration practitioners had insufficient information from which to choose sites effectively, and state and local agencies had a hard time properly evaluating shellfish restoration projects. That led to approval and permit delays, among other problems. The viewer helps users identify the best locations for siting shellfish restoration projects.