Sunflower sea stars released to rebuild kelp
Scientists deploy a 24-armed secret weapon to save California’s kelp forests
Wednesday, 14 October 2026
Photo by Erick Morales Oyola on Unsplash
Warm-up
- What comes to mind when you hear the word kelp?
- How can one species reshape an ecosystem?
- Have you ever seen conservation work near the sea?
Vocabulary
- restore
- to bring something back to its earlier, better condition
- invertebrate
- an animal without a backbone, such as a sea star or worm
- predator
- an animal that hunts and eats other animals
- ecosystem
- a community of living things and their environment
- sequester
- to capture and store a substance, such as carbon dioxide
- habitat
- the natural home where a plant or animal lives
- deterrent
- something that makes others less likely to act
- syndrome
- a disease or set of symptoms occurring together
Reading
Listen to this story
British EnglishOff the coast of Monterey, California, researchers from the non-profit Sunflower Star Laboratory are releasing sunflower sea stars to restore a damaged marine ecosystem. Led by co-founder Ashley Kidd, divers place the invertebrates in open cages on the seabed so the animals can roam. The species is critically endangered and unusual: not five arms but up to 24.
Kelp forests once dominated this coast, providing dense habitat that shelters thousands of species and helps power the ocean’s engine that produces roughly half of Earth’s oxygen. Kelp also sequester about 200m tons of carbon dioxide each year. But since around 2013, a marine heatwave driven by the climate crisis accelerated sea star wasting syndrome. More than 90% of sunflower sea stars vanished across the Pacific; there were once 6bn from Alaska to Baja California. With these predators gone, purple urchins exploded and 95% of local kelp forests disappeared in 10–12 years.
Scientists now aim to rebuild the stars’ “halo of fear”. Urchins smell a star and hide, eating less up to 16ft away. A single healthy star can devour three or four urchins a day, and its scent works as a powerful deterrent that gives kelp room to recover.
Comprehension
- Where are the researchers releasing the sea stars?
- Who is leading the dives, and for which organisation?
- What events since 2013 caused the sea star collapse?
- How much of the local kelp disappeared, and over what period?
- How do sea stars reduce urchin damage to kelp?
Grammar focus
Ellipsis and substitution
Use short forms to avoid repetition: so/neither + auxiliary + subject to agree or disagree; do so to replace a repeated action; one/ones to replace a repeated noun. Keep the auxiliary tense the same as the first clause. (Examples constructed.)
- Urchins hid; so did nearby fish.
- A weak star ate none; neither did the others.
Grammar exercise
Circle the correct option in each sentence.
- Stars devoured urchins; others (so did / did so).
- Kelp vanished; (so do urchins / so did urchins).
- This cage is open; the other (ones / one) is closed.
- Teams expect recovery; officials (think so / think it) too.
- Experts predicted recovery; locals (thought so / thought that).
Discussion
- Should governments fund kelp restoration at scale? Why or why not?
- Is reintroducing predators a good conservation strategy?
- What risks could this project face in the ocean?
- How could coastal communities support kelp recovery?
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