How many species exist on Earth? How many species are endangered? Joel Sartore knows all figures. Every life counts.  A world-known National Geographic photographer fights for life with his camera for more than 25 years.

It is folly to think that we can destroy one species and ecosystem after another and not affect humanity, he says. When we save species, we’re actually saving ourselves.

The only weapon Sartore ever used – his Nikon. Now Sartore is 56 but he is still in game. The other way round – Joel, from his own words, is in the middle of the journey and needs at least 15 years more to finish the job of his lifetime.

Sartore was born in Oklahoma, USA, got a degree in journalism at the University of Nebraska, signed a contract with National Geographic and became one of the best photographers of the magazine. His job allowed him to see the wide nature but also and a human impact on the environment first-hand.

Besides National Geographic, Sartore cooperated with: Audubon Magazine, GEO, Time, Life, Newsweek, Sports Illustrated, took part in TV-programs on NBC, CBS, PBS, USA Today и BBC made articles and shows about him.

The life of photographer changed tremendously in 2005, when his wife, Kathy, was diagnosed with breast cancer. His career as a National Geographic photographer came to an abrupt halt as he stayed home to tend to her and three children.

It’s been more than 10 years, and Kathy is fine now, but that year at home gave me a new perspective on the shortness and fragility of life. I was 42 at the time, and as Kathy recovered, one question continued to haunt me: How can I get people to care that we could lose half of all species by the turn of the next century?

This is how the project Photo Ark appeared. The identity of his encyclopedia of all species of the world was found by accident. He was making photos of the animals in zoo of Nebraska and put white paper as a “wallpaper”.

I thought maybe if we do eye-contact, if we photograph animals where there are no distractions, all equal in size on black and white backgrounds, where a mouse is every bit as big and amazing as an elephant, then maybe we could get the public hooked into the plight of endangered species and extinction, he says.

The most of his “patients” live in zoos around the world. The workers help Sartore with organizing the process of shooting, tell more about the character of animals. To make photo of a big animal Sartore prepares a special room, painted in white or black color in which workers of the zoo put delicious food for the animal. While it eats, Sartore makes photo.

Today on Earth exist 12 000 species. In Photo Ark you can find 7 885. This figure rises. On the website of the project is written: “Scroll down to see every species in the Ark … if you’ve got all day”. The image of each animal also has an interesting description. Joel put photos on the website, in printed books, copy in  Instagram, followed by more than 1 mln users. You can write to him through the official website or Facebook.

Some of the species captured by the Photo Ark are on the verge of extinction. In his interviews Sartore often mentions Toughie, the world’s last known living Rabbs’ fringe-limbed treefrog, who recently died in Botanic garden at Atlanta.

I try to talk about him every time I give public presentations because instead of getting depressed about him going extinct, I’m going to use his story to hopefully inspire others to care, he says.

The project of Sartore made interest for National Geographic, so soon Photo Ark transformed into The National Geographic Photo Ark, and the portraits of different species on black or white background were made on National Geographic Magazine covers and have been projected on to buildings — the UN Building and Empire State Building in New York and the Vatican in Rome.