Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)

Bangladeshi railway police try to clear line, as thousands of Bangladeshi Muslims gather to board trains to return home after attending three-day Islamic Congregation on the banks of the River Turag in Tongi, 20 kilometers (13 miles) north of the capital Dhaka, Bangladesh, Sunday, January 26, 2014. (Photo by A. M. Ahad/AP Photo)

“Hydrocynus goliath, also known as the goliath tigerfish, giant tigerfish or mbenga, is a very large African predatory freshwater fish. The giant tigerfish is restricted to the Zaire River system, Lualaba River, Lake Upemba and Lake Tanganyika”. (Photo by Tigerfishcamp / Tourettefishing / Bigfishesoftheworld)

An onlooker watches as the “Disney Fantasy” cruise ship is hauled backwards by a tugboat down the Ems River after the ship departed from the Meyer Werft shipyards on January 20, 2012 in Papenburg, Germany. The completed 130,000-tonne ship, which is 1,115 feet long and can accomodate 5,450 passengers, cast and crew, was on its way to the North Sea. (Photo by Sean Gallup/Getty Images)

A model Cindy Bruna presents a creation on a giant catwalk installed on a barge on the Seine River during a public event organized by French cosmetics group L'Oreal as part of Paris Fashion Week, France, September 30, 2018. (Photo by Stephane Mahe/Reuters)

Siberian Husky dogs of the Royev Ruchey Park team pull a rig during a practice session for the Karadag Sled Dog Rally on the frozen Mana River, with the air temperature at about minus 21 degrees Celsius (minus 5.8 degrees Fahrenheit), in the Siberian Taiga area outside Krasnoyarsk, Russia February 6, 2018. (Photo by Ilya Naymushin/Reuters)

After a cold night the small North Devon villages of Appledore and Instow wake up to an amazing scene as the sun rises over the River Torridge estuary, Devon, UK on October 19, 2018. (Photo by Terry Mathews/Alamy Live News)

A mother reacts as she pleads with police to allow her daughter to pass a checkpoint for cancer treatment after she arrived from Hubei province at the Jiujiang Yangtze River Bridge in Jiujiang, China, February 1, 2020. (Photo by Thomas Peter/Reuters)