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What animals eat mushrooms? Wildlife, pets and pests

By the MushroomGuide.ca Editorial TeamPet safety

Short answer: a lot of animals eat mushrooms — deer, squirrels, chipmunks, mice, box turtles, wild boar, slugs, snails and a long list of insects. Some of them eat mushrooms that would put a person in hospital, and they seem largely unbothered.

That last part is the reason this page exists, because it leads people to exactly the wrong conclusion.

The one thing to take away: an animal eating a mushroom tells you nothing about whether that mushroom is safe for you, your dog, or your goats. Tolerance is specific to the species eating it. Squirrels eat mushrooms that would kill a dog.

Wild animals that eat mushrooms

Deer

Deer are among the most frequent mushroom eaters in North American woodland, and they browse species that are dangerous to humans. They appear to tolerate at least some of those toxins, though the mechanism is not well established and almost certainly varies between species of mushroom and species of deer.

What is well established is that this tolerance does not transfer. It is not evidence about anything else that might eat the same mushroom.

Squirrels and chipmunks

Squirrels eat mushrooms fresh and also cache them — wedging caps into tree forks to dry, then retrieving them later in the year. They are known to take Amanita species that are seriously toxic to people.

Mice, voles and other rodents

Small rodents feed on mushrooms and on mycelium in leaf litter. They are also the reason an outdoor log stack or straw bed sometimes loses caps overnight with neat gnaw marks left behind.

Box turtles

Box turtles eat mushrooms readily, including species that are toxic to humans. This is worth knowing if you keep one — a tortoise or turtle loose in a garden may find and eat mushrooms you have not noticed.

Wild boar and pigs

Pigs root for fungi, truffles most famously, and domestic pigs will eat mushrooms found while foraging in woodland.

Slugs and snails

The most committed mushroom eaters in most gardens. Slugs will strip a flush of oyster mushrooms off an outdoor bed in a single damp night, and they are largely indifferent to which species it is.

Insects that eat mushrooms

If you grow mushrooms, this is the group that will actually cost you a harvest:

  • Fungus gnats (Bradysia, Lycoriella) — the classic indoor problem. The adults are a nuisance; the larvae are the damage, tunnelling through mycelium and substrate.
  • Phorid flies — smaller, faster, harder to exclude, and they carry contaminant spores between blocks.
  • Mushroom mites — usually a sign that a block has already gone off.
  • Springtails and fungus beetles — common in outdoor beds, mostly cosmetic damage.

Anything with a filter patch, a still-air space and a clean workflow keeps most of these out. Details in common mushroom contamination.

Livestock and mushrooms

Grazing animals encounter mushrooms constantly, especially in a wet autumn, and they do not avoid them reliably.

  • Goats browse indiscriminately and are the animal most likely to sample a mushroom in a paddock. See can goats eat mushrooms?
  • Cattle and sheep graze around mushrooms in pasture and poisoning cases are documented, usually after heavy rain brings a flush up overnight.
  • Pigs will actively root them out.

If you keep animals on ground where mushrooms appear, the practical advice is the same as for a dog: walk the paddock after rain, knock over and remove what has come up, and call a vet rather than waiting for symptoms if you think something has been eaten.

Pets

This is the part most people arrive here for, and we have it covered species by species:

Why “the animals eat it” is a dangerous test

It comes up often enough to be worth stating plainly. People see deer grazing on mushrooms, or squirrels caching them, and reason that anything wildlife eats must be edible.

It is one of the oldest and most dangerous pieces of folk wisdom about mushrooms, and it is wrong for a simple reason: tolerance to a given toxin is a property of the animal, not the mushroom. Amatoxins that destroy a dog’s liver may pass through a squirrel. A slug will happily eat a death cap.

MushroomGuide.ca is a cultivation-only site. We do not publish wild mushroom identification, and nothing here should be used to judge anything growing outdoors — see our foraging policy. If an animal in your care has eaten a mushroom you cannot account for, treat it as urgent: remove the rest, keep a sample in paper if you can safely collect one, note the time, and call your vet or the Pet Poison Helpline (1-855-764-7661).

What about the mushrooms themselves?

Worth clearing up a query that looks similar but isn’t: what do mushrooms eat. Mushrooms are not plants and do not photosynthesise — they digest organic matter externally and absorb it. For the species covered on this site that means hardwood sawdust, straw, or supplemented grain, which is what the substrate calculator is for.

And one genuinely strange answer: oyster mushrooms eat animals. Pleurotus species are nematophagous — the mycelium produces droplets of toxin that paralyse nematodes in the substrate, after which hyphae grow into the immobilised worm and digest it. It is thought to be a nitrogen-gathering strategy, straw and sawdust being rich in carbon and poor in nitrogen.

It has no bearing on eating them, and it is not why they are called oyster mushrooms. It is simply one of the odder facts about the most commonly grown gourmet mushroom in the world.

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