A police officer patrols as people party on a street as pubs shut for the night due to tier 3 restrictions in Soho, as the spread of the coronavirus disease (COVID-19) continues in London, Britain, December 15, 2020. (Photo by Henry Nicholls/Reuters)

France's Alice Finot celebrates next to the mascot winning silver in the Women's 3000m final at the 2021 European Athletics Indoor Championships in Torun on March 5, 2021. (Photo by Aleksandra Szmigiel/Reuters)

A protester poses for a photo in front of a burning barricade in Barcelona, Spain on February 17, 2021 as a protest following the imprisonment of rapper “Pablo Hasel” convicted to jail for glorifying terrorism and insulting Spain's former king in lyrics turns into riots for a second night. (Photo by Matthias Oesterle/ZUMA Wire/Rex Features/Shutterstock)

A trader speaks on the phone at his desk at the Frankfurt stock exchange, Germany, in this June 29, 2015 file photo. Federal Reserve policymakers are widely seen raising interest rates for the first time in almost a decade at their next meeting this week. (Photo by Ralph Orlowski/Reuters)

A Thai traffic security guard wears a Santa Claus costume as he directs the traffic on a street during Christmas celebrations outside a shopping mall in Bangkok, Thailand, 22 December 2015. The campaign of a shopping mall is held to celebrate the upcoming Christmas season and to attract shoppers. (Photo by Narong Sangnak/EPA)

Kazakh troops march during a parade of the armed forces to mark the Defender of the Fatherland Day in Astana, May 7, 2014. (Photo by Mukhtar Kholdorbekov/Reuters)

Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)