Level 1 - Absolute Beginner
In 2010 a big oil spill happened in the Gulf of Mexico. Oil went into the water for months.
Now scientists have a new study. They looked at animals deep in the sea.
Many animals are gone. Fish are down by about 64 percent. Shrimp are down by about 62 percent.
The animals have not come back. The scientists say the spill is the most likely reason.
- spill
- When a liquid escapes and spreads.
- study
- Careful work to learn about something.
- fish
- An animal that lives in water and has fins.
- shrimp
- A small sea animal that people eat.
- deep
- Going far down.
- scientist
- A person who studies the world with tests.
- percent
- A part of one hundred.
- recover
- To become healthy or normal again.
Level 2 - Elementary
A new study says life deep in the Gulf of Mexico has not recovered from the 2010 BP oil spill. It was published on Monday, October 19, in a science journal called PNAS.
The scientists studied the 'twilight zone', a dark layer of the sea where little sunlight arrives. They counted animals in 2011 and again about three and a half years later.
The numbers fell sharply. Fish dropped about 63.5 percent. Crustaceans such as shrimp and krill dropped about 62 percent. Squid and octopuses dropped about 59.7 percent.
The team checked temperature, oxygen and food. None of them explained the fall. The oil spill did.
- twilight zone
- The dark middle layer of the ocean.
- journal
- A magazine where scientists publish their work.
- layer
- One level above or below another.
- crustacean
- A sea animal with a hard shell, like a shrimp.
- krill
- Tiny sea animals that whales eat.
- oxygen
- The gas that animals need to breathe.
- explain
- To give the reason for something.
- sharply
- Very quickly and by a large amount.
Level 3 - Intermediate
A study published on Monday, October 19, in the journal PNAS reports that marine life in the Gulf of Mexico's deep 'twilight zone' fell sharply after the 2010 BP oil spill and has not rebounded. The work was led by Tracey Sutton of Nova Southeastern University and reported by the Associated Press.
Researchers compared a 2011 survey with a return visit about three and a half years later, using the same nets and sonar. Fish numbers fell about 63.5 percent. Crustaceans, which include shrimp and krill, a key food for whales, dropped about 62 percent, and larger animals such as squid and octopuses fell about 59.7 percent. Sea life had slid to between a quarter and a third of its 2011 level.
The team looked at natural explanations. Temperature, oxygen supply and food did not change in step with the decline. The one event that did was the oil spill, so they consider it the most likely cause.
There are limits. The region was not studied before the spill, so scientists have little baseline data. Boris Worm of Dalhousie University, who was not involved, described little visible recovery over the 13 years since. A separate 2024 study by Kaitlin Frasier found whale and dolphin declines of up to 83 percent.
- rebound
- To recover after a fall.
- survey
- A careful count or measurement of something.
- sonar
- Equipment that uses sound waves to find objects underwater.
- decline
- A steady fall in numbers.
- baseline
- A starting measurement used for comparison.
- marine
- Connected with the sea.
- supply
- The amount of something available.
- in step with
- Changing at the same time and pace as.
Level 4 - Advanced
A paper published in the Proceedings of the National Academy of Sciences concludes that the deep pelagic fauna of the Gulf of Mexico, the so-called twilight zone, collapsed in the years after the 2010 Deepwater Horizon blowout and has shown no meaningful recovery since. The study, led by Tracey Sutton of Nova Southeastern University, was reported by the Associated Press on October 19.
The design is straightforward. A survey in 2011 was repeated roughly three and a half years later with the same nets and sonar, so the comparison is like for like. Fish abundance fell about 63.5 percent, crustaceans including shrimp and krill, a staple for whales, by about 62 percent, and squid and octopuses by about 59.7 percent, leaving populations at a quarter to a third of their earlier size.
Causation is argued by elimination. Temperature, oxygen and food supply did not move in step with the decline, whereas the spill did coincide with it. The authors therefore regard it as the most probable driver, though the absence of pre-spill surveys means that the true starting point can never be reconstructed precisely.
Independent voices urge caution but not complacency. Boris Worm of Dalhousie University, who had no part in the work, noted that very little recovery is visible after 13 years, and a 2024 study by Kaitlin Frasier reported whale and dolphin declines as steep as 83 percent. Together the findings suggest that damage in the dark water column, long out of public view, may be persistent.
- pelagic
- Living in the open sea, far from shore.
- fauna
- The animals of a particular region.
- blowout
- A sudden, uncontrolled release of oil or gas from a well.
- abundance
- The amount of something present.
- staple
- A basic item of food that is eaten regularly.
- elimination
- The process of ruling out possible causes.
- complacency
- Satisfaction that stops people from taking care.
- persistent
- Lasting for a long time.
Talk about this article with KatePractice this story's vocabulary in a real spoken conversation with your AI tutor