Snake in the garden: how to identify it, why not to kill it, and what to actually do

Every year in Italy, thousands of harmless snakes are killed by people convinced they've done the right thing. The grass snake, the Western whip snake, the Aesculapian snake — hard to tell apart at a glance, instinct takes over, and in seconds a predator that was keeping the garden mouse population in check is gone.

The problem is it's illegal. And it almost certainly wasn't a viper.

Italy's snakes: who they really are

About 20 snake species live in Italy. Only vipers are venomous, and the country has 4 species: Vipera aspis (the most common), Vipera berus, Vipera ammodytes and Vipera ursinii (the last one extremely rare and at high extinction risk).

All others are harmless — or more precisely, non-venomous. They can bite if they feel threatened, but a grass snake or whip snake bite is at most as painful as a cat scratch, and only needs disinfecting.

How to identify a viper

Without getting too close, look for:

Stocky body: rarely over 70 cm, thick and robust — not slender
Triangular head clearly distinct from the neck, like a flattened arrowhead
Dark dorsal zigzag: the inverted-V pattern along the back is very distinctive
Short tail with a clear narrowing at the base
Vertical, elliptical pupil — like a cat's (if you can see it from a safe distance)

How to identify the grass snake

The grass snake (Natrix natrix) is probably the snake you'll most often see in gardens near water. It's easy to identify:

Two yellow-orange or white patches behind the head — the "collar" that gives it its name. This is the most immediate and reliable sign.
Slender body, often over a metre long
Oval head, not triangular, not distinct from the neck
Large, round pupil
Light belly with dark patches

If you see yellow patches behind the head: grass snake. Nothing to worry about.

How to identify the Western whip snake

The Western whip snake (Hierophis viridiflavus) is the fastest snake in Europe — it can reach 6 km/h. Juveniles are grey with dark diamonds; adults are glossy black or yellow-green striped. Small, narrow head, round pupil. It may puff up its neck and hiss when threatened, but the bite is completely harmless.

Why you shouldn't kill it (and what you risk if you do)

All Italian snakes are protected by law, vipers included. The legal reference is Law 157/1992, supplemented by Art. 727-bis of the Penal Code. Killing a wild snake without an immediate, demonstrable danger that couldn't be avoided any other way can result in up to 2 years in prison and fines of up to €30,000.

Ecologically, every snake removed from an ecosystem creates a vacuum that rodents quickly fill. Areas without snakes see explosions of mice, voles and rats — with all the knock-on problems for crops, buildings and public health.

What to do if you find one

In the garden or countryside: The vast majority of snakes you encounter are passing through — they don't "live" in your garden in the sense of a permanent den. Keep your distance, don't make sudden movements, and wait. It will go away on its own within minutes.

If you suspect it's a viper and it's in a frequented area: Don't try to drive it away or kill it. Call the Carabinieri Forestali or the local ASL veterinary service, or the nearest wildlife rescue centre. They'll handle capture and release in suitable habitat.

If it's an injured snake: Don't handle it without thick gloves. Contact a wildlife rescue centre.

Viper bite: what to do and what not to do

A viper bite is painful and needs medical care, but in Europe it causes around 1–2 deaths per year out of thousands of documented bites. Mortality is very low with proper treatment.

Do this:

Stay calm — agitation speeds up venom spreading through the blood
Remove rings and bracelets from the affected limb (swelling arrives fast)
Rinse the wound with plenty of water or diluted hydrogen peroxide
Go to accident and emergency — antivenom is administered in hospital, not at home

Don't do this:

Don't cut the wound or suck out the venom: it removes negligible venom and increases infection risk
Don't apply a tourniquet: it doesn't block the lymphatic system (the venom's route) and causes necrosis
Don't cauterise
Don't give alcohol or unprescribed medication
Don't waste time trying to catch or photograph the snake to "identify it": at A&E they'll treat the bite based on symptoms, not species

Something worth knowing

The grass snake is immune to toad venom — it eats them routinely, which most predators can't do. When it feels threatened, it performs a convincing death act: it rolls over, lets its tongue hang out, and sometimes produces bloody fluid from its mouth. It's a performance worthy of an actor.

The adult whip snake, by contrast, is one of Italy's most curious snakes: it tends to follow intruders with its head raised, not to attack but to investigate. If you encounter one and stay still, it will probably "study" you for a few seconds before moving on.