How Snakes Really Sense the World
Vision, Smell, Heat Detection and Why It Matters in Urban Snake Encounters
Snakes are often misunderstood animals. Many people assume they rely on a single sense — usually heat — or that they are either “blind” or supernaturally perceptive. In reality, snakes use a complex combination of sensory systems, each adapted to their habitat, lifestyle, and evolutionary history. Understanding how snakes see, smell, and detect their environment helps explain why they turn up in backyards, houses, roof spaces, and construction sites — and why professional handling is essential.
At Urban Reptile Removal, we deal with snakes daily across Sydney and New South Wales. What looks unpredictable to the public is usually perfectly logical behaviour once you understand how snakes perceive the world.
Snake Vision: Better Than You Think (But Not Like Ours)
Contrary to popular belief, most Australian snakes are not blind. Their eyesight varies widely depending on whether the species is active during the day or night, and whether it lives on the ground, in trees, or underground.
Diurnal (day-active) snakes — such as eastern brown snakes, red-bellied black snakes, and tiger snakes — generally rely more on vision than nocturnal species. These snakes have relatively well-developed eyes and can detect movement effectively, which is why they often flee rapidly when they see a person approaching.
Nocturnal snakes, on the other hand, tend to have larger eyes relative to their head size, allowing them to gather more light in low-visibility conditions. This is similar to owls, geckos, and many nocturnal mammals. However, good night vision does not mean sharp detail — it means sensitivity to contrast and movement.
Some burrowing snakes, such as blind snakes, have highly reduced eyes covered by scales. These snakes can still detect light and dark but rely heavily on other senses.
The key takeaway: snakes are not stalking humans. They usually see us as large, unpredictable threats and attempt to escape.
Smell: The Snake’s Most Important Sense
A snake’s most powerful sense is chemoreception, or smell. This is where the iconic forked tongue comes in.
When a snake flicks its tongue, it is collecting microscopic scent particles from the air and ground. These particles are delivered to a specialised sensory organ in the roof of the mouth called Jacobson’s organ (also known as the vomeronasal organ).
Because the tongue is forked, the snake can determine direction — comparing scent strength on each side. This allows snakes to:
Follow prey trails hours or even days old
Locate mates during breeding season
Navigate familiar territory
Detect predators
Research has shown that some snakes can follow scent trails with remarkable accuracy, even after rain or long delays. This explains why snakes may repeatedly appear in the same yard or garden — they are following established scent pathways, not randomly wandering.
Heat Sensing: Not All Snakes Have It
Heat-sensing pits are one of the most misunderstood snake features. Only certain snakes — including pythons and some overseas species like pit vipers — possess specialised heat receptors capable of detecting infrared radiation.
Australian pythons use these sensors to detect warm-blooded prey, even in complete darkness. These pits allow them to pinpoint prey location with extraordinary precision.
However, most Australian venomous snakes do not have heat pits. Browns, tigers, taipans, and black snakes rely primarily on smell, vision, and vibration. This is an important myth to dispel: snakes are not “locking onto” human body heat from a distance.
Vibration and Touch: Feeling the Ground
Snakes are extremely sensitive to vibrations transmitted through the ground. While they lack external ears, vibrations travel through their jawbones and body directly to the inner ear.
This is why snakes often retreat before you ever see them — they felt you coming. It also explains why sudden movements, stomping, or machinery can flush snakes from cover, sometimes straight into open areas like lawns, pathways, or buildings.
In urban environments, vibrations from:
Lawn mowers
Construction equipment
Vehicles
Foot traffic
can displace snakes from their normal shelter sites.
Why Snakes Enter Houses and Yards
When you understand snake sensory systems, urban snake encounters make far more sense.
Snakes are not attracted to houses — they are responding to:
Shelter (cool, dark, protected spaces)
Prey (rodents, frogs, lizards)
Scent trails
Seasonal movement, particularly during breeding
A snake entering a garage, bathroom, or laundry has not “chosen” the room. It has followed a scent trail, thermal gradient, or escape route and ended up somewhere unintended.
Once inside, snakes often remain still, relying on camouflage and immobility — a natural defence strategy that works extremely well in the wild.
Evolution Shapes Snake Behaviour
Different snake species have evolved distinct body shapes, senses, and behaviours depending on their environment:
Tree-dwelling snakes are slender with excellent climbing ability
Burrowing species have reinforced skulls and reduced eyesight
Aquatic snakes have flattened tails for swimming
Ambush predators rely heavily on camouflage and patience
This evolutionary diversity explains why no two snake encounters are the same — and why experience matters.
Why Professional Snake Removal Is Essential
Snakes rely on instinct, not reasoning. When threatened, cornered, or confused, even a normally placid species can behave defensively.
Professional snake catchers understand:
How snakes interpret movement
When a snake is stressed or preparing to flee
How to position themselves safely
How to guide a snake without triggering defensive behaviour
At Urban Reptile Removal, our approach is based on behavioural understanding, not force. Every safe relocation depends on reading the snake correctly.
Final Thoughts
Snakes are not aggressive, malicious, or targeting humans. They are highly specialised animals navigating a world of scent, vibration, light, and heat — a world very different from ours.
Understanding how snakes sense their environment helps reduce fear, prevent dangerous interactions, and highlights why trained professionals are essential when snakes appear in urban settings.
If you encounter a snake, keep your distance and contact a licensed expert. The safest outcome for both people and snakes is calm, informed handling.
Urban Reptile Removal
Sydney’s trusted professionals in safe, ethical snake relocation.
