Snorkelers interact with a Florida Manatee inside of the Three Sisters Springs in Crystal River, Florida January 15, 2015. On winter days, Florida manatees flock by the hundreds to the balmy waters of Three Sisters Springs, drawing crowds of snorkelers and kayakers to the U.S. sanctuary, where people may swim with the endangered species. But as tolerant as the gentle, whiskered sea giants can be of the accidental kicks and splashes of delighted tourists, wild life regulators want to ban most canoes and paddle boards and create people-free zones to protect the wintering “sea cow”. Proposed limitations for this winter are awaiting approval by the U.S. Fish and Wildlife Service. (Photo by Scott Audette/Reuters)

“The giant clam, Tridacna gigas (known as pā’ua in Cook Islands Māori), is the largest living bivalve mollusc. T. gigas is one of the most endangered clam species. It was mentioned as early as 1825 in scientific reports. One of a number of large clam species native to the shallow coral reefs of the South Pacific and Indian oceans, they can weigh more than 200 kilograms (440 lb) measure as much as 120 cm (47 in) across, and have an average lifespan in the wild of 100 years or more”. – Wikipedia

Photo: Tridacna Gigas, or Giant Clams spew water as a traditional fisherman passes by a small sanctuary on January 23, 2004 near Bolinao in the Northern Philippines. The clams, prime builders for coral reefs and providing shelter for spawning fish and other marine life, are exposed by low tides in the sanctuary. Overfishing and pollution throughout the country are not only threatening food security, but are also starting to choke one of the few working clam sanctuaries in the world. (Photo by David Greedy/Getty Images)

An Andean man and a woman, depicting Inca's legendary characters Manco Capac and Mama Ocllo, pose for a portrait in a Uros island at Lake Titicaca before a re-enactment in Puno November 5, 2014. The Uros islands are a group of 70 man-made totora reed islands floating on the lake, which according to Peru's tourism board iPeru is the world's highest navigable lake at over 4,000 meters above sea level. The Uros people fish and hunt, but tourism is their main source of livelihood. (Photo by Enrique Castro-Mendivil/Reuters)

Water is seen on part of the glacial ice sheet that covers about 80 percent of the country is seen on July 17, 2013 on the Glacial Ice Sheet, Greenland. As the sea levels around the globe rise, researchers affilitated with the National Science Foundation and other organizations are studying the phenomena of the melting glaciers and its long-term ramifications. The warmer temperatures that have had an effect on the glaciers in Greenland also have altered the ways in which the local populace farm, fish, hunt and even travel across land. In recent years, sea level rise in places such as Miami Beach has led to increased street flooding and prompted leaders such as New York City Mayor Michael Bloomberg to propose a $19.5 billion plan to boost the citys capacity to withstand future extreme weather events by, among other things, devising mechanisms to withstand flooding. (Photo by Joe Raedle)

Igor Shpilenok works in the reserve at Kamchatka, Russia. Igor is a fellow of the International League of Conservation Photographers and a winner of the 2006 BBC Wildlife Photographer Competition. Igor’s work has been published in numerous international and Russian magazines, including Smithsonian, National Wildlife, Geo, and BBC Wildlife.

“How does a bear behave when encounter a human? In most cases he runs away. But before running he almost always would rise to stand on his rear feet. And this behavior does not indicate the attack, as many people think...” – Igor Shpilenok. (Photo by Igor Shpilenok via Wildlife Photo Russia)

Fans dressed as Darth Vader and Chewbacca take a boat trip to the Skelligs on May 4, 2018 in Portmagee, Ireland. The first ever Star Wars festival is taking place against the backdrop of the famous Skellig Michael island which was used extensively in Episode VII and Episode VIII of the popular science fiction saga. The small fishing village of Portmagee, which is closest to the location, has seen a boom in tourism following the latest films. The vilage will host a Star Wars drive-in and a Star Wars themed Irish dancing competition over the weekend. (Photo by Charles McQuillan/Getty Images)

“YagYang”. The Apatani are tribal people living in north east of India in the region of Arunachal Pradesh. Tattooing and stuffing of large nose plugs is the particularity of these women. YagYang 75 years old, her husband passed away few months ago and she feels very alone, during my visit I was very fond of this woman and I wanted to spend some more time with her, so I asked her which was her favorite dish. The next day i returned with the fresh fish, as she mentioned, and when she saw me she was very happy and welcomed me with a big smile. Photo location: India. (Photo and caption by Passarini Mattia/National Geographic Photo Contest)

Fisherwomen laying barrels with salt in preparation for herring curing, 1937. (Photo by Topical Press Agency)