She picked one and then another, but only the cap came with it - the stem broke away, leaving the bulb behind.
She found it in her jacket pocket on the Sunday, washing it and after leaving it to dry noticed it had turned an inky black colour.
A cap of a death cap mushroom similar to that which Dr Anna Whitehead ate last month. This mushroom was found under the same oak tree in Raglan. Photo / Dr Whitehead
Doing an average of 16-hour days with Covid-19 related issues, Dr Whitehead said she was supposed to double check the status of the mushroom but in her haste forgot and instead cooked it up for lunch the following day.
In the early hours of Wednesday morning, Dr Whitehead woke being violently sick for most of the night until about 8am.
Crippled with sickness, she googled "poisonous mushrooms NZ", up popped a photo of the death cap mushroom.
"I recognised it instantly. It came with a description of how even one can be fatal, with liver transplant as the only treatment."
After heading to her local medical centre for help, she had another bout of illness 24 hours later and went to Waikato Hospital telling them she'd eaten a fatally poisonous mushroom.
The spot where the death cap mushrooms can be seen under an oak tree along the popular beachfront walkway. Photo / Supplied
She was now experiencing a second and more serious attack on her liver, while her kidney was also feeling the affects. After 15 hours in the High Dependency Unit, her liver finally began to stabilise.
Knowing what she'd ingested helped hospital staff get on with treatment quickly.
"People die because they eat it one day and it's not till the next day that they get sick.
"But if [people] don't realise it, and if they don't immediately associate it, they don't realise that they have to go to hospital and then people are thinking that they've got appendicitis or maybe you've got something else and then by the time they've figured out what you've got it's a bit too late."
Dr Whitehead, who is currently on a Covid-19 contract with Te Puna Oranga Maori Health team at the Waikato DHB, was eating healthy and not had any alcohol for 3 months prior to eating the mushroom which she believes helped her recovery.
Another death cap mushroom was spotted under the same oak tree on May 1. Photo / Dr Whitehead
A month on, she felt better but was still not 100 per cent.
"The worst pain was basically afterwards. After I got home [from hospital] it was really hard to even drink water.
"[First night] I just felt really, really sick when I woke up and I couldn't really think and couldn't stop vomiting huge amounts. It wasn't normal vomiting. It was like I had cholera.
"It was weird.
"I'm just getting better now. It's been four weeks, I'm pretty weak, I didn't move for two weeks and my levels have only just gone back down, they're not quite normal yet.
"Basically [the mushrooms] killed a bit of my liver and my kidneys."
As for why she picked it up, Dr Whitehead said because she "just came across it" while out on her walk.
"But if I had have been out looking for mushrooms then I would have thought 'oh, obviously I need to make sure that I identify these mushrooms and don't eat them until i'm sure what they are'.
The oak tree under which the poisonous mushrooms were found. Photo / Dr Whitehead
"In the past I remember doing that and have thrown them all away because I've looked it up and it says you can't tell the difference between good ones and bad ones."
Now that she was getting better, her focus was on prevention - given the mushrooms were about 100m from Raglan's town centre under a tree on a popular walkway.
"My key concerns now are that nobody else eats them. The one I actually ate looks kind of normal.
She'd been in contact with the National Poison Centre who advised not to forage for mushrooms.
"it's very difficult because you literally only need to eat one and it will kill you."
Dr Adam Pomerleau, director of the National Poison Centre, said death cap mushroom poisonings were extremely rare in New Zealand.
Dr Whitehead's case was the first definitive case that he had dealt with in his three years in the job.
"When it comes to mushrooms and exposure, the poison centre certainly gets its handful of exposure calls every year about mushrooms but we never really have a definite diagnosis or an identification of the mushroom.
"It's pretty rare for us to hear about a case that fits, like in Dr Whitehead's situation, where there were pictures of the mushroom and the clinical effects that happened to her."
However, that wasn't to say they didn't happen, they might not get reported to the centre or the mushroom involved wasn't found.
"My tips are to avoid foraging. It's really hard to identify a mushroom. It's much safer just to eat the mushrooms you get at the grocery store or the supermarket."
If anyone suspects they have eaten a poisonous mushroom they're asked to call the National Poison Centre on 0800 764 766 or 0800 POISON.
