The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

“Carli Davidson is both an internationally recognized award winning photographer and an experienced animal trainer and caretaker. She is able to capture the innate personalities of her subjects using her professional understanding of animal behavior. She is a freelance photographer for the Oregon Zoo, and works regularly with domestic animals both commercially and personally for her fine art projects”. (Photo by Carli Davidson)

Pontoons, which were previously used as a floating jetty, are seen on the cracked ground of the Atibainha dam, part of the Cantareira reservoir, during a drought in Nazare Paulista, Sao Paulo state February 12, 2015. Brazil's worst drought in 80 years has left the Cantareira system, that provides greater Sao Paulo with most of its water, with the lowest water level on record. Brazil's economy is already expected to post zero growth this year. Worse yet, since Brazil depends on hydroelectric dams for about three quarters of its electricity, power shortages are also possible due to the drought, federal officials have said. (Photo by Paulo Whitaker/Reuters)

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

Touching and dramatic portraits and landscape shots have won prizes at Australia's prestigious photography prize. Photo: Winner of the NSW (New South Wales) prize: Peter Solness said: “I wanted to re-imagine the lost waterways, so I got my light-painting tools to work. In this image, water is being released from the top of the historic Centennial Park No. 2 Reservoir, which was built in 1925 and holds 90 megalitres of water. After 89 years of incarceration these waters now run free!”. (Photo by Peter Solness/Head On)

In this photo taken on Saturday, January 26, 2019 photo, rescued flamingo chicks have access to water at a centre after being rescued from a dried out dam in Kimberley, South Africa. A special airlift for thousands of baby flamingos is under way in South Africa as drought has put their breeding ground in peril. A reservoir that hosts one of southern Africa's largest flamingo populations is drying up. (Photo by AP Photo/Stringer)

Guatapé is a town and municipality in Antioquia Department, Colombia. Part of the subregion of Eastern Antioquia. Guatapé is located in the outskirts of Medellín, bordering a reservoir created by the Colombian government for a hydro-electric dam, built in the late 1960s. This quaint town is the gathering place for "Las Vegas", or the small farms of the area. It is also a growing area of recreation for citizens of Medellín, and aims to be a tourist destination for foreign travellers.
Guatapé was founded in 1811, by the Spaniard Don Francisco Giraldo y Jimenez. The name "Guatapé", comes from the Quechua language, related to "stones and water". The area was visited by the conquistadors circa 1551.

This series of pictures shot by satellite, show the man-made world as astronauts see it. Artist Benjamin Grant uses Google Earth to find the most compelling satellite images of human civilization. The stunning pictures of sprawling metropolises and vast reservoirs are sometimes unidentifiable until zoomed in. In order to find an extraordinary picture in the practically endless supply of satellite data, Benjamin focuses on the themes of current events or environmental issues. Here: Industrial Sector, Tokai, Japan. (Photo by Benjamin Grant/Digital Globe/Caters News)