Fish farms: Food wave of fu­ture

IT’S WHAT’S GO­ING TO BE FOR DIN­NER As Earth pop­u­la­tion swells, is aqua­cul­ture next sus­tain­able wave?

USA TODAY Weekend Extra - - FRONT PAGE - @eweise USA TO­DAY

El­iz­a­beth Weise MON­TEREY

Farmed fish has got­ten a bad rap, but it’s the only way the world is go­ing to feed the 2.4 bil­lion peo­ple ex­pected to be added to the Earth’s pop­u­la­tion in the next 34 years, ex­perts told a sus­tain­able food con­fer­ence here last week.

With the world’s arable land maxed out and wild seafood over­fished, aqua­cul­ture is the one place we can look to pro­duce enough an­i­mal pro­tein for all those ex­tra mouths, said Steve Gaines, a pro­fes­sor of marine bi­ol­ogy at the Univer­sity of Cal­i­for­nia-Santa Bar­bara and lead in­ves­ti­ga­tor for the univer­sity’s sus­tain­able fish­eries group.

And as stan­dards of liv­ing rise, peo­ple eat more pro­tein, es­pe­cially meat. In China, for ex­am­ple, an­nual meat consumption has risen from 28 pounds per per­son in 1982 to 138 pounds in 2015.

Grow­ing enough crops to feed more pigs, chick­ens and cows isn’t pos­si­ble be­cause most of the world’s land that be planted al­ready is. Plow­ing un­der the mar­ginal land that’s left would only lead to de­for­esta­tion and land degra­da­tion, con­tribut­ing to cli­mate change, said Gaines.

Turn­ing to the world’s oceans doesn’t help. Analysis of global fish­eries, even if all were sus­tain­ably man­aged for max­i­mum pro­duc­tion, would take care of only between 1% and 5% of the com­ing de­mand, Gaines said.

Aqua­cul­ture, though, is a hard sell in the United States, pan­elists said, blam­ing U.S. prej­u­dice on NIMBYism (i.e. Not in My Back­yard). Amer­i­cans seem con­tent to eat farmed salmon, shrimp, oys­ters and other species when pro­duced far away but don’t want to see fish farms and pens in their pris­tine wa­ters at home.

And a neg­a­tive con­no­ta­tion with fish farm­ing per­sists among the more eco-con­scious be­cause of early un­sus­tain­able at­tempts, like farmed salmon and shrimp, in South Amer­ica and Asia.

Asian seafood pro­duc­ers have been clean­ing up their acts, but dam­ag­ing sto­ries about aqua­cul­ture there con­tinue to make the rounds, said Kevin Fitzsim­mons, a pro­fes­sor of aqua­cul­ture at the Univer­sity of Arizona in Tuc­son. He says he of­ten hears Amer­i­cans com­plain about agri­cul­tural leav­ings and an­i­mal waste be­ing used in fish ponds in South­east Asia, a prac­tice that’s ac­tu­ally both sus­tain­able and deeply rooted in the cul­ture, he said.

“In the United States, if some­body puts chicken waste in their gar­den, they’re an or­ganic farmer and it’s won­der­ful. But if they put it in a fish pond in China, we say they’re try­ing to kill us,” he said. To­day a wave of in­no­va­tion and in­vest­ment has meant that aqua­cul­ture over­all is much more en­vi­ron­men­tally friendly and ef­fi­cient than it once was.

An on­go­ing is­sue is that ocean­go­ing fish, es­pe­cially salmon, must be fed food that con­tains omega-3 fatty acids to taste like their wild coun­ter­parts. While fresh­wa­ter fish such as tilapia and cat­fish don’t need this, salmon tra­di­tion­ally have been fed feed that con­tains ground fish­meal. That meant that it could take as much as 2 pounds of fish to grow 1 pound of salmon.

Now mul­ti­ple com­pa­nies are work­ing to cre­ate al­gae and yeast­based feeds to make fish feed fully veg­e­tar­ian, Fitzsim­mons said. While there’s room to im­prove, on­go­ing tech­no­log­i­cal and man­age­ment ad­vances mean that fish farm­ing has be­come a very eco­log­i­cal way to pro­duce food.

“The po­ten­tial is for aqua­cul­ture to be a highly sus­tain­able, low-im­pact pro­tein,” Gaines said. Asia, which has prac­ticed pond and rice paddy-based aqua­cul­ture for mil­len­nia, pro­duces more than 70% of all seafood from aqua­cul­ture, ac­cord­ing to the Food and Agri­cul­tural Or­ga­ni­za­tion of the United Na­tions.

“Thanks to aqua­cul­ture, the global per-capita sup­ply of fish is at an all-time high,” said Ed­ward Al­li­son, a pro­fes­sor of marine and en­vi­ron­men­tal af­fairs at the Univer­sity of Washington in Seat­tle.

Fish isn’t the only aqua­cul­ture prod­uct be­ing pro­duced in Asia. Korea has developed a com­mer­cial method for mak­ing high qual­ity pa­per us­ing red sea­weed, said Fitzsim­mons. Some­day sea­weed farms planted just off­shore of large cities could take up farm runoff nu­tri­ents and CO2, low­er­ing pol­lu­tion and cli­mate-chang­ing gasses.

A city “could ac­tu­ally be car­bon-pos­i­tive” just from sea­weed farms, Fitzsim­mons said.

Amer­i­cans tend to think salmon when they think aqua­cul­ture. To­day, 78% of the salmon Amer­i­cans eat is farmed, ac­cord­ing to re­search by Oai Li Chen at the Univer­sity of Washington. How­ever, as a whole, salmon makes up just one-fifth of world aqua­cul­ture pro­duc­tion, said Corey Peet, a found­ing mem­ber of the Asian Seafood Im­prove­ment Col­lab­o­ra­tive.

Pop­u­lar farmed fish in Asia in­clude carp, tilapia Asian sea bass, snap­pers and groupers, said Fitzsim­mons. His fa­vorite is tilapia, which he said is to seafood as chicken is to poul­try.

And tilapia isn’t just for eat­ing. He proudly showed off his vest, which looked to be made of black leather but was in fact tanned tilapia skin made in Brazil. “You can re­ally do a lot with it,” he said.



A boy in In­dia holds a milk­fish, which has been grown in fish ponds in Asia for cen­turies. The sys­tem is eco­log­i­cally friendly.


A se­ries of com­mer­cial fish ponds in Shan­dong, China

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.