Villagers from the Porto Novo community load into their canoes arapaima or pirarucu, the largest freshwater fish species in South America and one of the largest in the world, while fishing in Poco Fundo lake along a branch of the Solimoes river, one of the main tributaries of the Amazon, in the Mamiraua nature reserve near Fonte Boa about 600 km (373 miles) west of Manaus, November 26, 2013. Catching the arapaima, a fish that is sought after for its meat and is considered by biologists to be a living fossil, is only allowed once a year by Brazil's environmental protection agency. The minimum size allowed for a fisherman to keep an arapaima is 1.5 meters (4.9 feet). (Photo by Bruno Kelly/Reuters)

An Indian Sadhu, or Hindu holy man, sits for a community feast at the Sangam, the confluence of the Rivers Ganges, Yamuna and mythical Saraswati, during the annual month-long Magh Mela religious fair in Allahabad, India, Friday, January 16, 2015. Hundreds of thousands of devout Hindus are expected to take holy dips at the confluence during the astronomically auspicious period of over 45 days celebrated as Magh Mela. (Photo by Rajesh Kumar Singh/AP Photo)

Pedestrians and traffic cross Tower Bridge as viewed through a glass viewing platform on the high-level Walkways during a preview to launch the new viewing experience at the Tower Bridge Exhibition centre in London on November 10, 2014. The new glass flooring at the Tower Bridge Exhibition 42 metres above the river Thames will allow visitors to gaze down on the bridge and river and allow them to experience the bridge opening from above. (Photo by Andrew Cowie/AFP Photo)

People pass by a vehicle almost completely submerged on a street covered with mud due to heavy floods in Tekija village September 17, 2014. One person died in Serbia and authorities scrambled to evacuate hundreds of people from villages threatened by rising rivers, officials said on Tuesday, in scenes recalling the devastating May flooding that killed dozens. (Photo by Djordje Kojadinovic/Reuters)

Men push a motorbike through a street flooded by a river that overflowed from heavy rains caused by Hurricane Matthew in Leogane, Haiti, Wednesday, October 5, 2016. Rescue workers in Haiti struggled to reach cutoff towns and learn the full extent of the death and destruction caused by Hurricane Matthew as the storm began battering the Bahamas on Wednesday and triggered large-scale evacuations along the U.S. East Coast. (Photo by Dieu Nalio Chery/AP Photo)

Schoolchildren look at a lifelike animatronics display of a dinosaur at the dinosaur-themed Zoo-rassic Park in Singapore on November 16, 2016. To raise awareness on the sixth mass extinction, the Singapore Zoo and River Safari displayed lifelike dinosaur animatronics where visitors can trail along the Dinosaur Valley which does not involve living animals. (Photo by Roslan Rahman/AFP Photo)

A damaged traffic signal is pictured along a street at a residential area flooded by the Kinugawa river, caused by typhoon Etau in Joso, Ibaraki prefecture, Japan, September 11, 2015. Unprecedented rain in Japan unleashed heavy floods on Friday that tore houses from their foundations, uprooted trees and forced more than 100,000 people from their homes. (Photo by Issei Kato/Reuters)

Master of throat singing (or Khoomei) Aikhan Orzhak (L) and model Choigana Kertek, dressed in traditional costume, perform during sunset at the Aldyn Bulak area on the bank of the Yenisei River outside the village of Ust-Elegest in Tuva region, Southern Siberia, Russia, October 7, 2015. The region is inhabited by Tuvans, historically cattle-herding nomads, who nowadays practise two main confessions – Buddhism and Shamanism. (Photo by Ilya Naymushin/Reuters)