News / Science & Technology

    As Ocean Supply Dries Up, Fishing For a Feed Alternative

    A trout farm project in the state of Potosi, Bolivia, March 28, 2013. With the supply of wild-caught fish dwindling, the U.S. Fish and Wildlife Service is working to develop a fishless feed that carnivores, such as rainbow trout, salmon and tuna, will actually eat.
    A trout farm project in the state of Potosi, Bolivia, March 28, 2013. With the supply of wild-caught fish dwindling, the U.S. Fish and Wildlife Service is working to develop a fishless feed that carnivores, such as rainbow trout, salmon and tuna, will actually eat.
    Tom Banse
    The search is on for a cost-effective alternative to traditional commercial feed pellets given to farmed fish.

    Wild-caught fish are a key ingredient in these commercial feeds but that presents a problem because the amount of ocean-caught fish has plateaued while the global aquaculture industry continues to grow. 

    The U.S. Fish and Wildlife Service is working with fish farmers and university researchers to develop a fishless feed that carnivores, such as salmon, rainbow trout and tuna, will actually eat.

    Taste test

    That's what brings dozens of taste test volunteers to Washington State University's School of Food Science's test kitchen.

    They are presented with three samples of trout - plain, poached pieces of fish that are all alike, except for how they were raised; one was fed fish meal, another ate animal proteins and the third ingested a mostly vegetarian diet.

    Some testers report a little bit of "grassy" flavor from what turned out to be the vegetarian-fed trout fillet. The trout raised on traditional fish meal had slightly more fishy flavor and aroma. The trout that ate chicken byproducts did not taste like chicken.
    Trout samples at the Washington State University School of Food Science. Alternative feeds resulted in slightly different colors and textures in trout fillets. (VOA/T. Banse)Trout samples at the Washington State University School of Food Science. Alternative feeds resulted in slightly different colors and textures in trout fillets. (VOA/T. Banse)

    The definition of success in this aquaculture experiment would be for the non-fish alternative diets to yield fish that taste more or less the same as those raised on the current fish-based feed.

    "I think they are getting close," said Professor Carolyn Ross, who has been conducting these taste tests since 2008. "Certainly, there are differences between samples, but whether that is a game changer or not is a different question. So yes, I can tell one has a more fishy aroma. I can tell one is firmer. But if you're sitting down at home having a BBQ, it's not going to make a big difference."

    Hitting the limit

    Aquaculture is a huge industry worldwide, especially in Asia, where the production of farmed fish, eels and shrimp dwarfs the production on all other continents combined. The U.N.’s Food and Agriculture Organization reports that farming of fish that eat pond plants or bottomfeed - like carp, catfish and tilapia - is expanding slower than production of carnivorous species - such as salmon, rainbow trout and tuna. That makes the search for a cost-effective alternative to fish-based feed more urgent.

    It's the industry’s number one priority, according to longtime fish farmer Leo Ray of Idaho, the leading trout producing state in the United States. Ray says fish meal that cost $300 per ton about 15 years ago, now runs close to $2,000.

    "We knew this was coming," Ray said. "There is a limit on the amount of fish meal the ocean can produce and we've hit that limit."

    Ray says the suppliers he buys from have already reduced the wild fish content in commercial feeds somewhat. He and his competitors in southern Idaho have gladly tested all sorts of alternative diets. They've fed their fish poultry byproducts, corn and soybean protein, coconut oil, and ground up insect larvae.

    "Salmon are harder to wean off fish meal," Ray said, pointing out that other farmed species, like tilapia, could fairly easily be converted to a plant-based diet. But he doubts going completely vegetarian is the answer.

    "We have healthier fish if we put a little bit of fish meal in the diet. I think what we will end up with is a diet that instead of using 20 or 30 percent fish meal, we'll be using five percent fish meal."

    The U.S. Fish and Wildlife Service says the effort extends to other aquaculture species as well. Parallel studies are testing alternative feeds for farmed Atlantic salmon and several species of warm water fish. Separate studies by university researchers in Texas and Alabama have investigated plant-based diets for farmed shrimp.

    You May Like

    In Britain, The Sun Still Doesn’t Shine

    Invoking Spitfires and Merlin, Leave voters insist country can be great again, following surprising 'Brexit' vote last week

    Double Wave of Suicide Bombings Puts Lebanon, Refugees on Edge

    Following suicide bombings in Christian town of Al-Qaa, on Lebanon's northeast border with Syria, fears of further bombings have risen

    US Senators Warned on Zika After Failing to Pass Funding

    Zika threats and challenges, as well as issues of contraception and vaccines, spelled out as lawmakers point fingers

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Slow Rebuilding Amid Boko Haram Destruction in Nigeria’s Northeasti
    X
    June 29, 2016 6:15 PM
    Military operations have chased Boko Haram out of towns and cities in Nigeria’s northeast since early last year. But it is only recently that people have begun returning to their homes in Adamawa state, near the border with Cameroon, to try to rebuild their lives. For VOA, Chris Stein traveled to the area and has this report.
    Video

    Video Slow Rebuilding Amid Boko Haram Destruction in Nigeria’s Northeast

    Military operations have chased Boko Haram out of towns and cities in Nigeria’s northeast since early last year. But it is only recently that people have begun returning to their homes in Adamawa state, near the border with Cameroon, to try to rebuild their lives. For VOA, Chris Stein traveled to the area and has this report.
    Video

    Video Clinton Leads Trump, But Many Voters Don't Like Either

    In the U.S. presidential race, most recent polls show Democrat Hillary Clinton with a steady lead over Republican Donald Trump as both presumptive party nominees prepare for their party conventions next month. Trump’s disapproval ratings have risen in some recent surveys, but Clinton also suffers from high negative ratings, suggesting both candidates have a lot of work to do to improve their images before the November election. VOA National correspondent Jim Malone has more from Washington.
    Video

    Video New US Ambassador to Somalia Faces Heavy Challenges

    The new U.S. envoy to Somalia, who was sworn into office Monday, will be the first American ambassador to that nation in 25 years. He will take up his post as Somalia faces a number of crucial issues, including insecurity, an upcoming election, and the potential closure of the Dadaab refugee camp in Kenya. VOA’s Jill Craig asked Somalis living in Kenya’s capital city Nairobi how they feel about the U.S. finally installing a new ambassador.
    Video

    Video At National Zoo, Captivating Animal Sculptures Illustrate Tragedy of Ocean Pollution

    The National Zoo in Washington, D.C., is home to about 1,800 animals, representing 300 species. But throughout the summer, visitors can also see other kinds of creatures there. They are larger-than-life animal sculptures that speak volumes about a global issue — the massive plastic pollution in our oceans. VOA's June Soh takes us to the zoo's special exhibit, called Washed Ashore: Art to Save the Sea.
    Video

    Video Baghdad Bikers Defy War with a Roar

    Baghdad is a city of contradictions. War is a constant. Explosions and kidnappings are part of daily life. But the Iraqi capital remains a thriving city, even if a little beat up. VOA's Sharon Behn reports on how some in Baghdad are defying the stereotype of a nation at war by pursuing a lifestyle known for its iconic symbols of rebellion: motorbikes, leather jackets and roaring engines.
    Video

    Video Melting Pot of Immigrants Working to Restore US Capitol Dome

    The American Iron Works company is one of the firms working to renovate the iconic U.S. Capitol Dome. The company employs immigrants of many different cultural and national backgrounds. VOA’s Arman Tarjimanyan has more.
    Video

    Video Testing Bamboo as Building Material

    For thousands of years various species of bamboo - one of the world's most versatile plants - have been used for diverse purposes ranging from food and medicine to textiles and construction. But its use on a large scale is hampered because it's not manufactured to specific standards but grown in the ground. A University of Pittsburgh professor is on track to changing that. VOA’s George Putic reports.
    Video

    Video Orphanage in Iraqi City Houses Kids Who Lost their Parents to Attacks by IS

    An orphanage in Iraqi Kurdistan has become home to scores of Yazidi children who lost their parents after Islamic State militants took over Sinjar in Iraq’s Nineveh Province in 2014. Iraqi Kurdish forces backed by the U.S. airstrikes have since recaptured Sinjar but the need for the care provided by the orphanage continues. VOA’s Kawa Omar filed this report narrated by Rob Raffaele.
    Video

    Video Re-Opening Old Wounds in a Bullet-Riddled Cultural Landmark

    A cultural landmark before Lebanon’s civil war transformed it into a nest of snipers, Beirut’s ‘Yellow House’ is once again set to play a crucial role in the city.  Built in a neo-Ottoman style in the 1920s, in September it is set to be re-opened as a ‘memory museum’ - its bullet-riddled walls and bunkered positions overlooking the city’s notorious ‘Green Line’ maintained for posterity. John Owens reports from Beirut.
    Video

    Video Brexit Resounds in US Presidential Contest

    Britain’s decision to leave the European Union is resounding in America’s presidential race. As VOA’s Michael Bowman reports, Republican presumptive nominee Donald Trump sees Britain’s move as an affirmation of his campaign’s core messages, while Democrat Hillary Clinton sees the episode as further evidence that Trump is unfit to be president.
    Video

    Video NASA Juno Spacecraft, Nearing Jupiter, to Shed Light on Gas Giant

    After a five-year journey, the spacecraft Juno is nearing its destination, the giant planet Jupiter, where it will enter orbit and start sending data back July 4th. As Mike O'Sullivan reports from Pasadena, California, the craft will pierce the veil of Jupiter's dense cloud cover to reveal its mysteries.
    Video

    Video Orlando Shooting Changes Debate on Gun Control

    It’s been nearly two weeks since the largest mass shooting ever in the United States. Despite public calls for tighter gun control laws, Congress is at an impasse. Democratic lawmakers resorted to a 1960s civil rights tactic to portray their frustration. VOA’s Carolyn Presutti explains how the Orlando, Florida shooting is changing the debate.

    Special Report

    Adrift The Invisible African Diaspora