Should iNaturalist hide poisonous mushroom locations after the Erin Patterson trial?

Australia Broadcast Center

10-07-2025

On Monday, a jury found Erin Patterson guilty on all counts — three charges of murder and one of attempted murder using death cap mushrooms.
The prosecution argued Patterson saw posts about death cap mushrooms (Amanita phalloides) on a niche citizen science website called iNaturalist.
In the wake of the trial, fungi experts are debating whether or not to continue allowing exact locations of poisonous mushrooms to be visible on public databases.
iNaturalist allows anyone to post photos, exact locations of animals, plants and fungi — including poisonous mushrooms.
Once the photo is uploaded, the community helps identify the species.
The observations can then be used by foragers, researchers or the general public to track mushroom locations, and avoid or remove those that could be poisonous.
Jasmin Packer, a conservation biologist at the University of Adelaide urged people to not stop making observations and uploading them.
"We still really want people to post photos of all fungi," she said.
"But it's a question whether people … need to be protected from some of the harmful fungi being posted."
Dr Packer is the vice president of Fungimap, a large citizen science project that records fungi around Australia using iNaturalist.
While only a small number of the 120,000 fungi observations on Fungimap identify death cap mushrooms, Fungimap makes up about a quarter of the iNaturalist observations of death cap mushrooms recorded in Australia.
Dr Packer suggested more discussion was needed to come to a consensus within the community of fungi experts on whether extra safeguards should be added for viewing the observations.
"We need to have some roundtable discussions around how best to deal with that," she said.
"It's an important conversation."
Michael Priest, president of Fungimap and a mycologist, said completely hiding the observations from public view was not a solution he was comfortable with.
"We did have a brief discussion at our recent AGM on how we should flag these things," Dr Priest said.
"I spoke out strongly against hiding records because I believe iNaturalist … is also a very good educational tool."
Many iNaturalist observations list the exact location, including longitude and latitude of where the mushrooms are found.
This can be extremely useful in certain situations, and allows people — particularly those who forage for mushrooms — to avoid locations where death cap mushrooms might be present.
But if this data is being misused, Dr Packer suggests the "obscure" function on iNaturalist could keep the observation public, but conceal the exact location.
When locations are obscured, instead of a small dot, a large square is placed over the map, and only a general area is provided.
In all other ways, the observation can be viewed as normal.
This can be done easily when uploading a record, and is already used when a rare plant or mushroom needs to be protected from visitors.
"You'll be able to see the record, but the location will be fuzzy," Dr Packer said.
Dr Priest said this was a good solution in the short term, but argued it might have unintended consequences down the track.
"It's something that could be considered by people if they were wary about it … at least until things have quietened down again," he said.
"But I think at some point in time we would need to know some of those records, because we are interested in tracking how [death cap mushrooms] are spreading throughout the country."
While most people that use websites like iNaturalist are enthusiasts, there are also a number of research and government organisations that use the data.
Observations that have been designated "research grade" — when multiple people agree on the identification of the species — are added into the Atlas of Living Australia and the Global Biodiversity Information Facility.
The Atlas of Living Australia is a collaboration between governments, CSIRO and Australia's museums, and is considered "Australia's national biodiversity database".
"There are governments in several states that have programs where they actually go out and collect all the sporebodies of [death cap mushrooms]," Dr Packer said.
"Over several weeks they're constantly monitoring to see where the [mushrooms] appear, and removing them to keep people safe."
For example, in the 2025 season, the ACT Government's City Services removed almost 900 death cap mushrooms from locations across Canberra.
Dr Priest noted that because death cap mushrooms were associated with oak trees, it was extremely hard to remove them once they were established in a location.
"American oak trees that were planted back in the 1950s and '60s as a sign of the American-Australian relationship … We believe that's one of the reasons that it came into Australia — at least into Canberra."
"Because it's associated with trees, unless you actually get rid of the tree, you won't get rid of the mushroom."
For Dr Priest, the good that comes from uploading poisonous mushrooms to databases like iNaturalist still vastly outweighs the bad, despite the outcome of the trial.
"The Erin Patterson case is such an unusual one, which, of course, is why it garnered so much interest from not just here, but from overseas," he said.
"It shows such things are possible whenever you start producing huge public databases or applications like iNaturalist.