These Mushrooms Could Be the Future in Treating Depression 1:01

(CNN) -- The slaughter was silent, the killers stealthy and the impact devastating.

The victims: more than 30 dogs highly trained to sniff out the valuable truffles growing underground near the damp, moldy roots of trees in the rural regions of Abruzzo and Molise in central Italy.

They were poisoned last weekend, according to the animal protection unit of the local carabineros. The dogs ate dumplings laced with what is believed to be metaldehyde and strychnine strategically hidden where the dogs would find them, out of sight of their owners.

It's not the first time sniffer dogs have been euthanized in the murky world of truffle picking. An average of 10 truffle dogs are killed each year in Italy, animal rights groups say. The toll could be higher, as many deaths go unreported, according to local collection associations.

Collectors fear that killing three times the average in one go is to send a message.

Rising prices

The autumn months are the truffle harvesting season in Italy. Marco Bertorello/AFP/Getty Images/File)

These deaths have cast a shadow over the multibillion-dollar network of pickers and merchants that supply Italian white truffles to some of the world's most exclusive restaurants. They also raise questions about what harvesters' groups say is one of Italy's least regulated traditional agricultural sectors.

All of this comes at a time when changing weather patterns, caused by the climate crisis, are reducing the supply of truffles, driving prices even higher. White truffles need wet, moldy forests and fields to thrive, but record-breaking heat and sweltering droughts have hit Italy harder than ever this season.

Meanwhile, global demand for this tuber by gourmets has skyrocketed in recent years, driving up prices.

A picker with an expert sniffer dog can earn thousands of dollars a day during truffle season, which typically runs from September to November. In 2022, a half-pound truffle sold for $200,000 at auction in Alba, Italy. At a current market value of $2,200 per pound, the white truffle is by far one of the most expensive foods in the world. Once turned into delicacies, these mushrooms often sell for upwards of $400 per tasting menu in cities like San Francisco and London.

"That's the price of the white truffle that a pompous waiter charges per plate in Tokyo, New York or London," Simon Martin, a professor of modern Italian history and licensed truffle picker, told CNN. "That's it: a dog convulsing and vomiting in a parking lot on a side street in downtown Molise."

Martin, who considers himself an amateur, says it all comes down to the economy controlling the market.

The pickers, known as "tartufai," sell their truffles to middlemen who then sell them to restaurants, exporters, or private chefs. Truffle pickers must pass a test to obtain a certificate that allows them to operate on any public land. They are required to follow the rules, including keeping their dogs muzzled.

A vendor smells white truffles at a truffle fair in northwestern Italy. (Marco Bertorello/AFP/Getty Images/File)

The mystery of who is behind the poisonings is the real bone of contention in this saga, with different players in the truffle supply chain blaming each other.

One picker told CNN that none of his local colleagues were active at the time of the poisoning, even though it was the height of white truffle season. CNN agreed to speak with the collector on condition of anonymity as he feared retaliation from other colleagues. CNN was unable to verify whether there were actually active collectors in the area at the time, but local collectors who spoke to CNN, also on condition of anonymity, denied having prior knowledge of the poisonings.

Police confirmed that the victims were dogs from other parts of the country that had arrived in the area after large white truffles were recently found.

An investigation into the deaths has been opened. But to date, not a single person has been arrested or convicted of previous dog killings.

One reason is that owners rarely press charges when they kill their dogs, says the local animal rights group. Some may not have properly registered, licensed or microchipped their dogs, as required by hunting regulations, and in other cases, the dogs were not wearing the muzzles required of hunters, police say.

Others remain silent for fear of reprisals, says Riccardo Germani, a third-generation truffle farmer who is president of Italy's National Association of Truffle Pickers. Cutting tires and even blowing up pickup trucks is not uncommon in the world of truffle picking, he says.

Code of Silence

Italian white truffles are prized for their spicy flavors. (Miguel Medina/AFP/Getty Images)

So far, none of the owners of the 30 dogs killed last weekend have filed a complaint, the local prosecutor's office told CNN, prompting calls from Italy's Italian Association for Animal Protection and the Environment for prosecutors to act.

They want the area where the poisoning took place to be closed for a year to truffle animals, in case there is still poison hidden in the undergrowth. They have also called on hunters to break their code of silence.

"We are concerned about the health of the dogs and the deaths of 30 of them should not go unnoticed as if it were a matter of interest only to truffle pickers," the group wrote in a letter to local collectors' associations and seen by CNN.

"30 dead dogs in a few days is a massacre and we believe it is appropriate for the truffle growers to speak, because we think that some of them have more than one suspicion about the name of the author or authors, so let's leave the silence aside and go to the prosecutor's office to tell the truth," he said.

The associations, of which there are many, want the authorities to carry out the investigations. "Let's not talk about a war between truffle pickers, this is a real massacre," Fabio Cerretano, president of the National Federation of Italian Truffle Associations, said in a statement after last weekend's events.

"He is a madman, a criminal who carried out this shameful gesture by killing dozens of truffle (dogs) to be left alone to look for truffles in that area," he added.

Fake 'Italian' truffles

Germani, president of Italy's National Association of Truffle Pickers, told CNN that dead dogs are the tip of the iceberg in terms of what's wrong in the truffle harvesting sector.

He says there is a lack of transparency about the origin of truffles when pickers sell them, including importing truffles from as far away as Iran, Afghanistan and, more locally, Croatia, which end up being certified for sale as Italian products.

"There are few controls in the world of truffle picking," he told CNN. "And we need controls, the state doesn't do them, so we have to do it ourselves," he added.

In a letter to the Ministry of Agriculture sent after the dog massacre, he wrote: "The Italian truffle sector, one of our national excellences, is suffering not only from illegal and cruel practices, but also from the lack of recognition and valorization."

Germani has called for the installation of cameras to monitor areas where poisonings occur, but says more measures need to be put in place.

"It is essential that the government steps in to ensure that truffle hunting remains an ethical and sustainable practice and not a business for a few criminals. This cultural and gastronomic heritage deserves greater protection and promotion to preserve its integrity and secure its future."