A record amount of sargassum piled up across the Caribbean and nearby areas in May, and more is expected this month, according to a new report. The amount—about 41 million tons, tallied through May—is the biggest quantity of algae observed across the Caribbean Sea, the western and eastern Atlantic, and the Gulf of Mexico since scientists began studying the Great Atlantic Sargassum Belt in 2011, said Brian Barnes, an assistant research professor at the University of South Florida who worked on the report published on Monday by the school's Optical Oceanography Lab. The previous record was set in June 2022, with some 24 million tons, and the new record is hardly stationary—experts said they expect even more sargassum in June. More from the AP: