One of Kenya's most adored elephants, who had giant tusks and was known as Satao, has been killed for his ivory—a "monumental" loss, experts say.

Poachers shot the bull elephant with a poisoned arrow in Tsavo East National Park, waited for him to die a painful death, and hacked off his face to remove his ivory, according to the Tsavo Trust, an area nonprofit that works with wildlife and local communities.

Satao was particularly appealing to poachers as a tusker, a type of male elephant with a genetic makeup that produces unusually large tusks. His tusks were more than 6.5 feet (2 meters) long.

"Kenya as a country contains probably the last remaining big tuskers in the world," said Paula Kahumbu, a Kenya-based wildlife conservationist with the nonprofit WildlifeDirect. (Read Kahumbu's essay on Satao's death in the Guardian.)

"To lose an animal like Satao is a massive loss to Kenya. He was a major tourist attraction to that part of Tsavo," said Kahumbu, who was a 2011 National Geographic Emerging Explorer.

The elephant was killed May 30, but members of the trust announced his death on June 13, after verifying the carcass's identity. (Related: "Efforts to Curb Ivory Trafficking Spreading, but Killing Continues.")

"It is with enormous regret that we confirm there is no doubt that Satao is dead, killed by an ivory poacher's poisoned arrow to feed the seemingly insatiable demand for ivory in far-off countries," the Tsavo Trust said in a statement.

"A great life lost so that someone far away can have a trinket on their mantelpiece." (Read "Blood Ivory" in National Geographic magazine.)

View Images Satao was killed by poachers and his face was hacked off in Tsavo East National Park in May 2014. Photograph by Mark Deeble and Victoria Stone, www.markdeeble.wordpress.com

"Massive and Hostile" Expanse

Satao died despite his high profile, which brought special protection.

"It's also a reflection on the situation in Kenya that even in a place where all efforts are made to protect the elephants, it's still very difficult to protect them," Kahumbu said. (Watch video: "Elephants in Crisis.")

For the past 18 months, the Tsavo Trust and the Kenya Wildlife Service have been monitoring Satao's movements by air and on foot. "When he was alive, his enormous tusks were easily identifiable, even from the air," according to the Tsavo Trust.

Satao generally kept to a predictably small area with four other bull elephants. But in search of food following big rains, he had recently moved into a boundary of the park that's a known poaching hot spot, especially for hunters with poisoned arrows. (Also see: "Poachers Slaughter Dozens of Elephants in Key African Park.")

Authorities noticed this and protection efforts were stepped up, but the area Satao entered "is a massive and hostile expanse for any single anti-poaching unit to cover, at least one thousand square kilometers [about 390 square miles] in size," according to the Tsavo Trust.

"Understaffed and with inadequate resources given the scale of the challenge, [Kenya Wildlife Service] ground units have a massive uphill struggle to protect wildlife in this area." (Related: "In War to Save Elephants, Rangers Appeal for Aid.")

Poaching's Toll

About 472,000 to 690,000 African elephants likely roam the continent today, down from possibly five million in the 1930s and 1940s. The animals are classified as vulnerable by the International Union for the Conservation of Nature.

Conservationists estimate that 30,000 to 38,000 elephants are poached annually for their ivory, which is shuttled out of West African and, increasingly, East African seaports en route mainly to China and other Asian consumer countries such as Thailand. (See a graphic of elephant poaching in Africa.)

The whereabouts of Satao's tusks are unknown, but Kahumbu said that they are likely on their way to being exported.

"What worries me is we're seeing increasing amounts of ivory moving through Kenya, and it's a real indicator of the corruption," she said.

Kenya has a history of dealing with celebrity elephants.

"One of the most powerful messages that Kenya ever made was when the first president of Kenya, Jomo Kenyatta, gave presidential protection to an elephant [named Ahmed] because of the size of his tusks," she said. (Read about how China and other countries are crushing their ivory stocks.)

"He died of old age because he had two armed guards with him 24-7," Kahumbu said. "This is the kind of measure our president Uhuru Kenyatta needs to do," Kahumbu emphasized.

"If we fail to protect these elephants, we lose the gene pool of big tuskers forever in Africa."