A changing of the honor guard ceremony by the Tomb of the Unknown Soldier in Alexander Garden by the Kremlin Wall in Moscow, Russia on May 29, 2020. (Photo by Vladimir Gerdo/TASS)

Mud Day Queen Riley Tulgetske, left, embraces Mud Day King Phoenix Crowder during Mud Day at the Nankin Mills Park, Tuesday, July 9, 2019, in Westland, Mich. The annual day is for kids 12 years old and younger. While parents might be welcome, this isn't an event meant for teens or adults. It's all about the kids having some good, unclean fun during their summer break and is sponsored by the Wayne County Parks. (Photo by Carlos Osorio/AP Photo)

Chicken, fish and eggs lie next to coca paste worth $14,000 Colombian pesos at a local store in Guyabero Region, Guaviare, Colombia, May 24, 2016. As the government nears a historic peace deal with the rebels of the Revolutionary Armed Forces of Colombia (FARC), the nation's authorities are struggling to tame an increase in farming of coca, the raw material used to make cocaine. In the Guyabero Region, where many people work on coca plantations, locals barter coca paste to buy groceries at the local shop. (Photo by John Vizcaino/Reuters)

A man bathes in an ice hole in the Neva River St. Petersburg, Russia, Wednesday, February 10, 2021. The temperature in St. Petersburg is –15C ( 5 °F). (Photo by Dmitri Lovetsky/AP Photo)

A man wearing a protective face mask walks past traditional large puppet figures called “Ondel-ondel”, also donning face masks and displayed along a sidewalk of a main road, as coronavirus disease (COVID-19) cases surge in Jakarta, Indonesia, June 30, 2021. (Photo by Willy Kurniawan/Reuters)

Ayaka Oshita, a 27-year-old diver, practices in preparation for the upcoming seasonal feeding performance as a Santa diver at Sunshine Aquarium at Ikebukuro in Tokyo, Japan, 07 December 2021. Oshita has 15-month experience for feeding fish at the aquarium after she joined the aquarium in 2019. The Santa diver performance will be held for three days around the Christmas time. The aquarium will not inform the performance time to avoid the visitors' crowd due to the COVID-19 pandemic. (Photo by Kimimasa Mayama/EPA/EFE)

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)