The Los Angeles Post
U.S. World Business Lifestyle
Today: April 03, 2025
Today: April 03, 2025

Sea urchins fed waste cabbage to spare Japan's seaweed forests

Kanagawa Prefectural Fisheries Technology Center's researcher Yutaka Harada feeds sea urchins with cabbage at the center's laboratory in Miura
July 25, 2024

By Tom Bateman and Kyung Hoon Kim

KANAGAWA, Japan (Reuters) - In Japan, researchers are feeding vegetables to hungry sea urchins - a popular sushi ingredient - to try and stop them from eating dwindling stocks of ocean seaweed.

The country is struggling with a "desertification of the sea" or "isoyake" problem, where the coastline faces a stark decrease in seaweed forests that host a diverse array of marine life and support the livelihoods of local fishers.

Sea urchins fed waste cabbage to spare Japan's seaweed forests
Kanagawa Prefectural Fisheries Technology Center's researcher Shozo Takamura and his colleague work to collect sea urchins for a survey of sea urchin numbers in Zushi

In Sagami Bay off the coast of Kanagawa, just south of Tokyo, the seaweed bed areas have decreased 80% over the past three decades, according to Kanagawa Prefectural Fisheries Technology Center researcher Yutaka Harada.

Scientists think overgrazing by herbivore sea urchins is a factor behind the phenomenon, along with the possible effects of a rising sea temperature and stronger tidal waves. But controlling the animal's population is not an easy task.

"There are a lot of sea urchins in the areas where seagrasses have disappeared," said another Kanagawa researcher Shozo Takamura. "Divers and fishermen dive down in their bathing suits to collect and get rid of them, but their numbers have barely fallen."

Unlike the urchins sold to luxury sushi bars, most sea urchins in coastal Kanagawa do not have many edible parts, making it less commercially viable for the fishers to keep catching them.

Sea urchins fed waste cabbage to spare Japan's seaweed forests
Volunteers take part in an event to collect sea urchins and ship them off to be used as fertiliser on local fields, in Zushi

But researchers are studying ways to nurture the creature caught in Kanagawa.

"The urchins we're raising here at the research centre, which are Pacific purple sea urchins, really love vegetables," like surplus cabbages that are given to us and Japanese mustard spinach, said Harada.

Local sea urchins tend to have a paltry 2-3% edible parts, but the lab-fed ones are as much as 20% edible, with less bitter taste, he added.

The project's findings mean the local urchins could become more valuable, creating a bigger economic incentive to catch them, and sparing the remaining ocean seaweed.

Sea urchins fed waste cabbage to spare Japan's seaweed forests
Kanagawa Prefectural Fisheries Technology Center's researcher Yutaka Harada feeds sea urchins with cabbage at the center's laboratory in Miura

"We're working towards raising even tastier sea urchins on land and selling them to support our efforts against ocean desertification," Harada said.

(Reporting by Tom Bateman and Kyung Hoon Kim; Writing by Kantaro Komiya; Editing by Alexandra Hudson)

Share This

Popular

Asia|Business|Economy|Finance|Political|Stock Markets|US

Dow drops 1,200 as US stocks lead worldwide sell-off after Trump's tariffs ignite a COVID-like shock

Dow drops 1,200 as US stocks lead worldwide sell-off after Trump's tariffs ignite a COVID-like shock
Americas|Asia|Business|Economy|Political

Emerging economies brace for Trump tariff 'turning point'

Emerging economies brace for Trump tariff 'turning point'
Asia|Environment|Health|Political|World

Myanmar earthquake death toll rises to 3,145 as more bodies found

Myanmar earthquake death toll rises to 3,145 as more bodies found
Asia|Political|World

Post-earthquake ceasefires in Myanmar offer rare opportunity for disaster diplomacy

Post-earthquake ceasefires in Myanmar offer rare opportunity for disaster diplomacy

Science

Environment|Science|US

Early look at hurricane season predicts over a dozen named storms. But El Niรฑo could change things

Early look at hurricane season predicts over a dozen named storms. But El Niรฑo could change things
Africa|Science|World

Ancient DNA sheds light on origins of 7,000-year-old Saharan mummies

Ancient DNA sheds light on origins of 7,000-year-old Saharan mummies
Education|Health|Political|Science|Technology

Susan Monarez, Trumpโ€™s nominee for CDC director, faces an unprecedented and tumultuous era at the agency

Susan Monarez, Trumpโ€™s nominee for CDC director, faces an unprecedented and tumultuous era at the agency
Food|Health|Science

Vitamin D builds your bones and keeps your gut sealed, among many other essential functions โˆ’ but many children are deficient

Vitamin D builds your bones and keeps your gut sealed, among many other essential functions โˆ’ but many children are deficient

Access this article for free.

Already have an account? Sign In