The Strait of Hormuz Is Now an Ecological War Zone Visible from Space

500+ oil spills, 20,000 sq km of cumulative pollution, and decades-long contamination locked into sediments. The US-Iran war is destroying Gulf marine ecosystems with no cleanup infrastructure and no accountability framework.

Eight months into the US-Iran war, the Strait of Hormuz has become both a military chokepoint and an environmental catastrophe. Greenpeace has identified more than 500 oil spill instances through satellite monitoring across the Gulf, the strait, and the Arabian Sea. The cumulative footprint of those spills covers approximately 20,000 square kilometres — roughly the size of Wales. More than 133 attacks on oil tankers have occurred since fighting began on 28 February, with October alone seeing over 30 confirmed or reported strikes.

The damage is not abstract. A strike on the supertanker Gem No 2 off the UAE coast produced a slick stretching 35 kilometres. A June attack on a tanker near Oman generated a slick covering more than 600 square kilometres at its peak. Two Iranian naval vessels hit in March continued leaking oil for months. The largest single spill was caused by a UAE air force strike on oil storage tanks on Lavan Island, according to the Wall Street Journal, which sent crude flooding into the Gulf and contaminating the nearby Shidvar Island nature reserves. The pollution has reached coastlines across the region. Oil from the Shahid Bagheri was detected near Iran's Hara mangroves in March. By April, contamination threatened protected Shidvar Island. In August, oil washed ashore at Qeshm Island near turtle nesting sites and fishing grounds. Satellite imagery shows slicks near Oman's Musandam national park and Iran's Minab River delta, both rich in coral reefs, seabird colonies, and mangrove forests. The Gulf's physical characteristics make it uniquely vulnerable. Bernhard Riegl, a marine biologist at Nova Southeastern University who has studied the Gulf for over 30 years, explains that the shallow, enclosed waters trap heat and pollutants with no deep-water buffer. Coral reefs, mangrove forests, and seagrass meadows — already under severe climate pressure — now face oil coating that blocks oxygen absorption in mangrove roots, smothers coral, and disrupts migration routes for dolphins, turtles, and fish. Historical precedent is grim. A 2020 study traced tar deposits on Qatari beaches to the 1991 Gulf War. A 2022 study found sediment on Saudi Arabia's Abu Ali Island still contaminated from the 1983-85 Nowruz spills during the Iran-Iraq war, which leaked 80 million gallons of crude. Riegl warns that any organism digging into contaminated beaches — sea turtles laying eggs, ghost crabs burrowing — will encounter polluted strata for decades. "This is a generational problem. We could really lose something irreplaceable." Cleanup responses have been localised and inadequate to the scale. The UAE closed beaches and launched a major operation after the Gem No 2 strike; Oman deployed divers and cleared 7 miles of coastline near the Hallaniyat Islands. But these are point responses to a systemic crisis. Oil trapped in sediments, shorelines, and mangrove roots will persist long after surface slicks dissipate, damaging marine food chains and threatening fishing communities. Accountability is fractured. Iran's IRGC has been blamed for most tanker attacks, but US forces have also struck Iranian vessels attempting to cross a naval blockade, and the UAE has conducted its own strikes. Researchers and environmentalists in Iran and Gulf states report being instructed by domestic authorities not to speak publicly about the damage. The naval blockade makes ground-level documentation nearly impossible, leaving satellite imagery as the primary evidence tool for a disaster whose full extent remains unknown.