When Asuka Takita was a young girl in Japan, her father gave her a carved ivory pipe engraved with a flower, which was passed down from her grandfather.
Back then, ivory was just a material. She knew nothing of the killing of elephants for their tusks.
In the 1970s and 1980s, Japan became the largest consumer of ivory in the world, contributing to the worst ever poaching in Africa. Meanwhile, Asuka developed a fascination with wildlife, particularly large mammals.
From gazing at pictures of elephants in books, she began visiting them at the zoo every week when her family moved from Japan to Singapore. Later, at college in the US, she majored in biology before pursuing a degree in zoology and learning the truth about the origins of ivory.
But it was not until she was in her early 20s, while on a college exchange programme, that she finally made it to Africa and saw an elephant in the wild for the first time.
"I fell in love with the whole place, everything about the Maasai Mara. It's the whole ecosystem that I like, including the people," says Asuka, who is now 41.
After graduation, Asuka got on a plane bound for Africa and vowed to make it her home. She enrolled in a five-year veterinary medicine degree at the University of Nairobi, Kenya, and afterwards began volunteering in the Maasai Mara.
Poachers can be armed, and could shoot if they see they are being followed
In 2008, she was given the position of veterinarian in the Mara Conservancy, which manages the northwest area of the Maasai Mara National Reserve, called the Mara Triangle.
Over the last eight years she has led an integral anti-poaching patrol tasked with protecting wildlife from people who want to kill it for bushmeat or for ivory.
The special thing about this team is that it is made up of both humans and dogs.
Ana is a bloodhound, one of four tracker dogs in the Mara Triangle. When the rangers find signs of poaching, whether it be a weapon, a trap or a dead animal, Ana is able to sniff a poacher's footprints for up to 30km to lead the team to the culprit's location.
It is dangerous work. Poachers can be armed, and could shoot if they see they are being followed.
Since the dogs were introduced to the Mara Triangle they have helped in the arrest of at least 150 poachers. But Asuka says that when the dogs first arrived from the US, where they were trained, things did not go quite to plan.
"We had to employ a new set of people and train them, but I was pregnant at the time and I couldn't run along with the dogs," she says. "Within a month nothing was working. The rangers weren't catching poachers and they weren't using the dogs. They stopped using them because they thought the dogs would take their jobs."
The dogs are able to sniff out the smallest piece of ivory
However, that changed after a tragic incident at a private campsite when robbers shot dead a white Kenyan farmer. Within half an hour of the attack, one of Asuka's tracker dogs was at the scene and began tracking the robbers. Twelve hours later, the dog brought the rangers to one of the robbers.
After that, the rangers put their trust in the dogs. Today they work efficiently to defend the land and the animals living within it.
But in 2013, when there was a rise in ivory poaching incidents in Kenya and across the continent, Asuka knew more had to be done. She consulted the dog trainer in the US about the possibility of teaching dogs to sniff out ivory, and it worked.
Garvey and Gage, two ivory detection dogs, arrived in Kenya the same year and were placed at the two gates of the Mara Triangle. The dogs are able to sniff out the smallest piece of ivory, wrapped in plastic and hidden in cars or in bushes.
They can also detect any firearms that people try to smuggle into the conservancy, or bullets fired by poachers.
Today, thanks in part to the ivory detection and tracker dogs, poaching has dropped dramatically in the Mara Triangle.
"I was here in 1996 and we couldn't go through some areas because there was so much poaching," Asuka says. "Now it's totally different. It's a success story."
Ivory is believed to carry good fortune
She says that bushmeat poaching, where poachers try to capture game like zebras and wildebeest to eat, and often inadvertently injure and kill larger mammals, is a big problem.
But ivory poaching is very rare in the area, as poachers know there is little chance of getting out of the Mara Triangle undetected.
Meanwhile the dogs are important for security in the park. After the 2010 murder in the Maasai Mara, and the 2013 terrorist attack at Nairobi's Westgate shopping mall, tourism in Kenya suffered terribly.
But Garvey and Gage stop any firearms from entering the Mara Triangle.
"Before, there was no deterrent. Anyone could pay a park fee and there was no scanning of vehicles," says Asuka. "We thought that was a scary thing especially since our revenue depends on tourism income."
Her work in the Maasai Mara was seeing results, but Asuka was conscious that, while her adopted country was desperately seeking to stop ivory poaching, her home country was still avidly consuming the exotic material.
No evidence is required by law to ensure ivory is of legal origin
While Japan's usage of ivory is lower today than 30 years ago, the country is still a major consumer. Ivory is believed to carry good fortune. In particular it is used for making hanko, a traditional stamp which is the only form of official signature accepted by banks in Japan.
Every adult in Japan needs a hanko, which is engraved with the owner's name, and while titanium, plastic, crystal and marble are occasionally used, ivory has always been the preferred choice.
Ivory hanko and other products are widely available on sites like Yahoo Auction, and Rakuten, a major Japanese e-retailer similar to Amazon.
Japan signed the global 1989 convention that banned the global trade in ivory and the only ivory that can be domestically traded is that which was imported before the ban.
But no evidence is required by law to ensure ivory is of legal origin, and campaigners say Japan is not doing enough to control the illegal ivory trade.
An undercover investigation in December 2015 by the US-based Environmental Investigation Agency found widespread fraud with more than 5,500 tusks registered as "legal" over the past four years. For consumers, there is no way of telling the difference between illegal and legal ivory.
People think that by buying ivory from African countries they are helping to tackle poverty in Africa
"To register ivory, you can just write a letter saying you saw your grandfather carrying around ivory and that's enough," says Asuka. "There is no DNA testing, no follow-up on the origin. More than 2,000 tusks were registered as antique last year. Where are they coming from?"
While Asuka was working to save elephants in Kenya, she wanted to do something to fight ivory demand in Japan.
But when she spoke to people in Japan, she realised there was a huge gap in knowledge.
"In Japan, ivory is just a material," she says. "There is no elephant element for them. Ivory is called 'zouge' and if people hear that word the immediate reaction is that it is a material. Most people really don't know about it. They say they thought it was taken from the dead elephant. Legal trade and ivory poaching is not connected. People think that by buying ivory from African countries they are helping to tackle poverty in Africa."
An obvious cause for the lack of knowledge is that the bulk of conservation campaigns are done in English.
Meanwhile, in the Japanese press, Asuka found little mention of poaching, and if there was anything on the issue it was about the problem in China.
"There is a lot of outcry about the ivory trade but none of it is written in Chinese and Japanese. All these articles say China and Japan are bad but it is not reaching the Japanese public. It made me wonder what I could do to cross the bridge," she says.
People would discontinue reading Facebook posts if they were gruesome
She and a fellow Japanese conservationist, Airi Yamawaki, who grew up in South Africa, launched Tears of the African Elephant, an NGO that targets a Japanese audience.
They translate news articles from English into Japanese and post them online, run campaign events in Japan and have published a children's book about elephants.
In 2016 they held the first Global March for Elephants and Rhinos in Tokyo.
But they have discovered that campaigning against ivory in Japan is a sensitive topic. Firstly, there is the Japanese way of doing things.
"The Japanese are sensitive people and don't like a hard truth," she says. "We were giving them the truth. But the Japanese have a saying, if you have something stinky you just put a lid on it. They really put a lid on it. People would discontinue reading Facebook posts if they were gruesome. We had to soften our message."
Secondly, the duo are going against the government.
"The Japanese government, the ministry of environment, of finance, foreign ministry, they totally support the use of ivory. They want to open the trade," says Asuka.
Because their NGO work contradicts government policy, companies are uneasy about partnering with them, she says, and they cannot apply for public grants.
They realised the legal trade is contributing to illegal trade in Africa
Asuka says that, in Japan, wildlife activists like the marine conservation organisation Sea Shepherd are thought of as terrorists and are blacklisted by the government. "We wanted to reach the public rather than the public hating us," she says.
But their campaigning is helping to bring about change.
Asuka believes that no consumer would want to buy an item if they knew an animal suffered for it and she is passionate about spreading her message.
In 2016, she and Airi did a number of media interviews prior to the international wildlife trade meeting Cites in South Africa where poaching of the African elephant was top on the agenda.
The meeting gained large amounts of media coverage in Japan, which Asuka says was unprecedented, and initiated a nationwide discussion on the ivory trade leading to three companies discontinuing sales of ivory hanko.
"They realised the legal trade is contributing to illegal trade in Africa. That is a huge thing for us," says Asuka.
An overnight ban on the domestic ivory trade is her "biggest wish" for crushing demand, but she is realistic. "The government is very difficult to move and it takes years, and elephants are facing imminent extinction," she says.
My son grew up in the Mara where you can see elephants all the time
Instead, she hopes dissuading consumers from buying ivory will save the species.
Her NGO is also in talks with the hanko industry to encourage companies to use elephant-friendly materials, such as titanium. "We want to work with partners within the hanko industry so that not using ivory becomes a good thing, rather than naming and shaming companies," she says. "That works much better in Japan."
There are signs the political atmosphere could change. In 2016, the First Lady of Japan, Akie Abe, visited Nairobi's David Sheldrick Elephant Orphanage. Asuka and Airi hope her visit could build momentum to raising awareness of ivory poaching and to Japan ending all ivory trade.
For Asuka, her drive is to do whatever she can to ensure that the elephants she grew up in awe of still exist when her son, now seven, is older.
"I wanted to do something for my son and the future generations," she says. "My son grew up in the Mara where you can see elephants all the time and to think it could disappear when he is a grown-up, that is a travesty."
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