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A free diver visited the Strait of Hormuz. Here's what he saw

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A free diver visited the Strait of Hormuz. Here's what he saw
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Why it matters

Talks have stalled over the Iran war, which means hundreds of ships are still stuck on either end of the Strait of Hormuz, as both sides of the war blockade the waterway.

Key takeaways

  • Above water, it's dotted with beautiful rock outcroppings and banks that some call the Oman Fjords.
  • He says all that marine life under the water could actually be a sign that things aren't going so well.
  • The Persian Gulf is actually the hottest sea in the world.BARTHOLOMEW: We saw spikes of water temperature of almost 37 degrees Celsius, which is your human body temperature.

Talks have stalled over the Iran war, which means hundreds of ships are still stuck on either end of the Strait of Hormuz, as both sides of the war blockade the waterway. But a couple weeks ago, another sort of vessel sailed right into the channel, stayed put for hours and found something surprising. NPR's Henry Larson has the story.

HENRY LARSON, BYLINE: OK, we're not talking about an oil tanker here, more like a big speedboat heading into one of the most dangerous waterways on Earth.

BUX KHURANA: I message everyone on the Indian free diving community that, guys, I'm going to the Strait of Hormuz.

LARSON: Bux Khurana hired that boat. He's an Indian free diver, lives in Dubai but competes for his national team. And a couple of weeks ago, he decided he wanted to free dive in the strait.

KHURANA: The water was green, which some people don't like, but for me, I like the green water. I like a little darkness.

LARSON: He ended up about 3 miles off the southern tip of the strait, an area called Shishah. Above water, it's dotted with beautiful rock outcroppings and banks that some call the Oman Fjords. But below, there's huge, diverse coral reefs.

LARSON: Bux dove in. And he saw something unique.

KHURANA: And I couldn't see them from the surface because the surface was full of jellyfish. I go down 20 meters, and I just see these five lionfish sitting together and chilling.

LARSON: Bux has done dives in the strait more than a dozen times in the last three years.

KHURANA: When I went into the deeper parts of the water, you can see fish everywhere - huge schools of fish, big fish, small fish.

LARSON: This was the most wildlife he'd ever seen in that spot.

KHURANA: I have never seen the amount of dolphins that I saw in this strait that day - maybe 50 dolphins doing backflips in the water, looking, like, very happy.

LARSON: It made him think, there are a lot fewer tankers heading through the Strait of Hormuz right now. Could that actually be helping the sea creatures there?

AARON BARTHOLOMEW: I mean, it's plausible.

LARSON: Aaron Bartholomew is a biology professor at the American University of Sharjah in the United Arab Emirates. He studied the marine life in the Persian Gulf for decades. Bartholomew says he's not sure the war has had a huge impact on marine animals, at least not yet.

BARTHOLOMEW: The number of dolphin and fish that you see on a day-to-day basis can certainly vary for a wide variety of reasons.

LARSON: But any answer to Bux's question requires us to learn more about the waters around the Strait of Hormuz. It turns out, it's more complicated than geopolitics. The Persian Gulf is actually the hottest sea in the world.

BARTHOLOMEW: We saw spikes of water temperature of almost 37 degrees Celsius, which is your human body temperature. It's like taking a bath.

LARSON: And it's home to a remarkable amount of sea life who all react to stress differently.

BARTHOLOMEW: And so the tuna come in, and the whale sharks follow them through the Straits of Hormuz seasonally.

MOHSEN REZAIE-ATAGHOLIPOUR: Moving through the Iranian coastline, you will see many small islands which house nesting populations of critically endangered hawksbill turtles and many coral reef communities.

LARSON: Mohsen Rezaie-Atagholipour is an Iranian marine biologist and Ph.D. researcher at the University of Manchester. He says all that marine life under the water could actually be a sign that things aren't going so well.

REZAIE-ATAGHOLIPOUR: When you start to disrupt an ecosystem, many animals try to leave their regular habitats and just struggling all around to find a new places to hide.

LARSON: Disruptions like underwater explosions, changes in shipping traffic and minor oil spills might be causing larger mammals, like dolphins, to flee to areas that might be safer, including the strait. But of course, these are just theories. Any proper analysis of what's changing under the waves will have to wait until after the conflict is over. Henry Larson, NPR News.

(SOUNDBITE OF STRAY KIDS SONG, "WALKIN ON WATER")

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Published: Apr 26, 2026

Read time: 4 min

Category: Science