Cormorant masters and boatmen prepare sea cormorants for the nights “Ukai” on July 2, 2014 in Gifu, Japan. In this traditional fishing art “ukai”, a cormorant master called “usho” manages cormorants to capture ayu or sweetfish. The ushos of River Nagara have been the official staff of the Imperial Household Agency of Japan since 1890. Currently six imperial fishermen of Nagara River conduct special fishing to contribute to the Imperial family eight times a year, on top of daily fishing from mid-May to mid-October. (Photo by Chris McGrath/Getty Images)

Villagers from the Medio Jurua nature reserve of Brazil's Amazon rainforest arrive with their catch of pirarucus, the largest freshwater fish in South America, after a night of fishing in Manaria Lake, Carauari municipality, September 3, 2012. Catching the pirarucu, 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. (Photo by Bruno Kelly/Reuters)

In this April 12, 2015 photo, Sayed Ahmed Abdoh poles his boat to check his fish traps in the Nile River, near Abu al-Nasr village, about 770 kilometers (480 miles) south of Cairo, Egypt. Abdoh caught some 20 fish this day and gave them to his friend, Salama Osman, a migrant worker in a Cairo apartment building, to celebrate his biannual return to their village. (Photo by Hiro Komae/AP Photo)

In this November 7, 2016 photo, “El Menor”, a member of “Los Cainos” self-defense group formed by the Marval fishing family, holds a homemade gun before starting a night patrol to help protect fishermen from pirate attacks in Punta de Araya, Sucre state, Venezuela. Pirates are terrorizing the coastal state of Sucre, once home to the world's fourth-largest tuna fleet and a thriving fishing industry. (Photo by Rodrigo Abd/AP Photo)

Angler Thomas Rielly catches a fish during the opening of the salmon fishing season on the River Tay January 16, 2012 in Kenmore, Scotland. A procession with a pipe band and anglers made its way through Kenmore at the east end of Loch Tay to mark the start of the 2012 salmon season on the River Tay. (Photo by Jeff J. Mitchell/Getty Images)

Bangladeshi fisherman feed their otters as they catch fish in Narail some 208 kms from Dhaka on March 11, 2014. The fishermen are using a rare technique that relies on coordination between man and trained otters, a centuries-old fishing partnership that has already long died out in other parts of Asia. (Photo by Munir Uz Zaman/AFP Photo)

Fishermen pull up a live 2.5 metre crocodile in their net in the Western Amazon region, Brazil on September 20, 2017. The fishermen were fishing for a large river fish called Arapaima but sometimes crocodiles become stuck in the nets as well. (Photo by Carl de Souza/AFP Photo)

People participate in a winter fishing event in Changchun, Jilin province, China, December 25, 2016. Picture taken December 25, 2016. (Photo by Reuters/Stringer)