SAN JUAN, Puerto Rico (AP) — Near-record amounts of seaweed are smothering Caribbean coasts from Puerto Rico to Barbados, killing fish and other wildlife, choking tourism and releasing stinky, noxious gases.

More than 24 million tons of sargassum blanketed the Atlantic in June, shattering the all-time record, set in 2018, by 20%, according to the University of South Florida’s Optical Oceanography Lab.

And unusually large amounts of the brown algae have drifted into the Caribbean Sea.

  • Lakes Beach is covered in sargassum in St. Andrew along the east coast of Barbados, Wednesday, July 27, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases. (AP Photo/Kofi Jones)
  • Lakes Beach is covered in sargassum in St. Andrew along the east coast of Barbados, Wednesday, July 27, 2022. More than 24 million tons of sargassum blanketed the Atlantic in June, up from 18.8 million tons in May, according to a monthly report published by the University of South Florida’s Optical Oceanography Lab that noted “a new historical record.” (AP Photo/Kofi Jones)
  • Long Beach is covered with sargassum in Crest Church parish along the south coast of Barbados, Wednesday, July 27, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases. (AP Photo/Kofi Jones)
  • A tractor sweeps a beach lined with seaweed along the Atlantic shore in Frigate Bay, St. Kitts and Nevis, Wednesday, Aug. 3, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases, according to the University of South Florida’s Optical Oceanography Lab. (AP Photo/Ricardo Mazalan)
  • A bird stands on seaweed covering the Atlantic shore in Frigate Bay, St. Kitts and Nevis, Wednesday, Aug. 3, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases, according to the University of South Florida’s Optical Oceanography Lab. (AP Photo/Ricardo Mazalan)
  • Seaweed covers the Atlantic shore in Frigate Bay, St. Kitts and Nevis, Wednesday, Aug. 3, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases, according to the University of South Florida’s Optical Oceanography Lab. (AP Photo/Ricardo Mazalan)
  • Seaweed covers the Atlantic shore in Frigate Bay, St. Kitts and Nevis, Wednesday, Aug. 3, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases, according to the University of South Florida’s Optical Oceanography Lab. (AP Photo/Ricardo Mazalan)
  • Seaweed covers the Atlantic shore in Frigate Bay, St. Kitts and Nevis, Wednesday, Aug. 3, 2022. A record amount of seaweed is smothering Caribbean coasts from Puerto Rico to Barbados as tons of brown algae kill wildlife, choke the tourism industry and release toxic gases, according to the University of South Florida’s Optical Oceanography Lab. (AP Photo/Ricardo Mazalan)

Scientists say the possible explanations include a rise in water temperatures as a result of climate change and nitrogen-laden fertilizer and sewage nourishing the algae.