Naibor was a gentle fellow, the largest and oldest white rhino living on the Oserian Wildlife Sanctuary (OWS) overlooking Kenya’s Lake Naivasha. His horn was three feet long, and he was a favorite of rangers and visitors. But earlier this month, in broad daylight, armed men got through the electric fence and shot Naibor dead with an AK-47 within earshot of a ranger’s post. Both his horns were hacked off before the poachers fled.

OWS mounted a massive tracking operation with police, rangers, tracker dogs and a helicopter, but the poachers escaped into dense bush. The dogs found the small horn stuffed down a hole, along with shoes and a shirt, and they later identified five soldiers from a nearby army barrack. The soldiers were arrested and then released due to lack of evidence, police said.

In the same week, five other rhinos were killed 150 miles north on Lewa Wildlife Conservancy, one of the best-managed private conservancies in Kenya. The poachers used automatic weapons and escaped through rough terrain. The dogs lost their tracks in Isiolo, a hub for the illegal wildlife cartels, for weapons and explosives smuggling, al Shabaab networking and human trafficking.

These brazen attacks show that the battle against rhino poaching is neither straightforward nor a guaranteed win.  When I asked a well-known Kenyan conservationist what he thought needed to be done to save the rhino, he hesitated. “How does it get stopped?” he asked rhetorically.“I stay awake at night asking myself that question.”

Though rhino poaching is not new to Kenya, the market for rhino horn has grown massively, along with its price.  In a country where the average person lives on about $2 a day, it’s almost impossible to protect a jewel attached to a lumbering weak-eyed giant wandering placidly through the bush.

In the 1970s, illegal hunting for rhino horn reduced Kenya’s population of black rhinos from 20,000 to about 300. For ten years, as many as five rhinos were killed every day.  But even with reduced numbers, rhino poaching continues.  South Africa, with about 20,000 rhino, loses two a day. Kenya, which now has fewer than 600 rhinos country-wide, lost more than 20 in 2012.

Rhino horn is worth more than gold. While the gunmen who kill the animal may only receive $10,000-20,000 dollars, by the time the horn gets to its biggest market, Vietnam, where people believe it can cure cancer, a gram of horn powder can cost $65,000.

Lewa, with 62,000 acres of windswept hills, scrub land and savannah, is one of my favorite places. Once a cattle ranch, it became a wildlife conservancy in 1995 and is now a global model for community-based conservation—a tourist destination, home to 350 species of birds and 70 mammal species including lion, buffalo, elephant, leopard and cheetah. It is also a leader in rhino preservation—home to 10 percent of Kenya’s black and 14 percent of its white rhino.

Keeping rhino is not for amateurs. The cost of protecting wildlife nearly doubles with black rhino present. Lewa has established a veritable army to protect its animals—and it is expensive.  Encircled by an electric fence, Lewa has 150 armed rangers, surveillance teams, radio operators, dog handlers, a fence maintenance team, night guards and aerial surveillance. The conservancy works extensively with the Kenya Wildlife Service (KWS) and—critically—with local communities, which provide labor, and informers.

So who poached Lewa’s rhinos? A massive investigation is underway in the conservation community. Several people told me that only locals or former employees—including possibly employees charged with rhino security—would have known their way in and out of the ranch. Lewa officials describe the rhino as a ‘Kenyan national asset’ and warn that attacks could escalate across Kenya.

Another reason rhino are vulnerable is that their horns are so portable.  Elephant tusks need to be moved by vehicle, but rhino horn can be hand-carried. “Rhino horn, like drugs, counterfeit currency or illicit diamonds, is a high-value black-market product that, once it leaves the hands of the poacher, is moved through a series of couriers, onto godfathers coordinating these activities,” explained Ian Craig, Lewa’s founder, in a speech to American zoo-keepers. Slipped into a shoulder bag, the horn probably left Isiolo by car and then Kenya by plane within hours of the killings.

While elephant poachers are often caught with tusks, in Kenya only twice have police caught someone with rhino horn.  Without the horn, prosecution is nearly impossible. Moreover, anti-poaching laws offer little deterrence, as penalties are grossly outdated. Magistrates know little about wildlife crime.  Most poachers get charged with misdemeanors. Fines are paid immediately, in cash. One poacher has been arrested, fined and released five times. High-level corruption may be partly to blame, as there is certainly enough money to go around.  And if there is no corruption, there may simply be indifference:  the Kenyan Minister for Wildlife has yet to issue a statement about the recent poachings.

Paula Kahumba, executive director of WildlifeDirect, which blogs to support conservationists, argues that no African government has invested the resources needed to stop poaching. “The truth is that the demand for ivory and rhino is so great that you can’t save it on your own,” Paula says, adding that KWS has its heart in the right place but does not have the wealth or manpower to investigate and prosecute. “The wildlife laws are inadequate given the scale of the problem. We are talking to the government trying to convince them to use the Economic and Organized Crime Act in Kenya.”

It is difficult to know how this will end.  It is a classic ‘tragedy of the commons.’  We are collectively richer with rhino, but for many of the poor, individually, it is better to kill the rhino and market its horn—even if, in the end, there are no rhino or rhino horn left over.  For a desperately poor breadwinner, one horn can make all the difference between feeding and educating children, or consigning them to a life of poverty as well. It is not a fight that conservationists alone can win.