On Sunday, a storm in the Black Sea sank five ships and ran others aground, including an oil tanker that split in half, spilling about 550,000 gallons of fuel oil — roughly half its cargo. Two other ships carrying fuel oil were among those that hit shore, but they apparently didn’t spill anything. At least two of the sunken ships were carrying thousands of tons of sulfur, which is expected to be much less harmful to the marine environment than the fuel oil. Up to five sailors were also killed in the storm. Officials and environmentalists expect that at least some of the heavy fuel oil spilled will sink to the ocean floor, making cleanup extremely difficult. “It’s more or less possible to clean up our coast and clean the oil which you can see on the water,” said Ecodefense’s Vladimir Slivyak. “But if it goes down, it’s nearly impossible to clean it from the bottom. So from my point of view, the consequences for the marine environment will last for [the] next decade.” The spill’s most visible effect on wildlife was the 1,000 or so seabirds seen coated with oil and unable to fly, but the spill is also expected to affect other critters and the area’s fishing industry.