MOSCOW — A hunter in Russia’s far east was sentenced Tuesday to 18 months of community service and fined about $18,500 for killing a Siberian tiger, a rare case in this country of punishment for poaching the endangered animal.

Khasan District Court found Alexander Belyayev guilty of killing one of the remaining 500 tigers in the Maritime and Khabarovsk territories.

Ecologists hailed the verdict as a success in the struggle to protect the species. An estimated 30 to 50 tigers are killed each year by poachers and residents, said Vladimir Krever, head of the World Wildlife Fund’s Russian biodiversity program.

“Of dozens of cases related to tiger killings over the last three years, this is the second guilty verdict, and such a harsh one that leaves us a hope that it may serve as a good lesson to potential poachers,” Krever said in an interview.

“Usually tigers’ skins and remains are found already in transit and not at the killing spot,” he noted, “and a person caught with the remains, as a rule, says that he found the dead tiger in the taiga or on the side of the road and gets off free.”

Between the breakup of the Soviet Union in 1991 and 2009 only one person was found guilty of killing a tiger.

Belyayev, who was accused in October 2010, did not deny that he killed the tiger but insisted he acted in self-defense, showing authorities his own light injuries.

Investigators concluded that Belyayev spotted a tiger while hunting antelope and shot it twice, injuring two paws. He followed the fleeing animal and shot it three more times. At that point, authorities said, the tiger charged the hunter and injured him, causing Belyayev to run for home.

Hunting inspectors discovered the animal after it had bled to death.

Belyayev was deprived of his hunting license and his hunting rifle was confiscated.

Krever said Siberian tigers are usually killed by poachers for their skin, meat and internal organs, with portions of the animal used in traditional Chinese medicine.

“Poachers could get several thousand dollars for a tiger body if they could smuggle it to China, which is also becoming increasingly difficult these days,” he said, adding that the fine given Belyayev might help discourage hunters.

Russia is considering legislation to toughen penalties for killing rare animals as well as for transporting their bodies and selling them.