What Do Snakes Eat?

Snakes do not hunt people, and they are not indiscriminate eaters. Like all predators, snakes eat what is available, manageable, and worth the energy. In Australia, that diet has been shaped by climate, geography, and the unusual mix of animals found on the continent.

Unlike many animals, snakes swallow their prey whole. This places a physical limit on what they can eat. A snake cannot chew or tear food into pieces (with very rare exceptions), so prey must fit through the mouth and down the body. As a result, most snakes feed on prey that is long, flexible, or small enough to swallow intact.

Why Australian Snake Diets Are Different

Australia is one of the driest continents on Earth. Many areas have unpredictable rainfall, long droughts, and poor soil productivity. These conditions influence which animals are common — and therefore which animals snakes can eat.

Small mammals, birds, and freshwater fish are relatively scarce across much of Australia compared to other continents. Because of this, Australian snakes rely more heavily on reptiles, frogs, and occasionally other snakes, rather than mammals alone.

Snakes are ectothermic (cold-blooded), meaning they do not need to eat frequently. This allows them to survive in environments where food availability changes dramatically from year to year.

The Most Common Prey: Lizards and Frogs

Lizards

Australia is often called “the land of the lizards”, and for good reason. Lizards are abundant, diverse, and active across most habitats. As a result, lizards form the main diet of many Australian snakes, especially smaller species.

Skinks are particularly important prey. They are widespread, active during the day, and often found in large numbers. Young snakes frequently feed on juvenile skinks, which are easier to swallow.

Frogs

Frogs are another major food source, especially after rain. Many frogs spend long periods underground during dry conditions, then emerge in large numbers when rain falls. Snakes take advantage of these short-lived feeding opportunities.

Some snakes specialise in frog-eating, while others take frogs opportunistically when they are abundant.

Mammals and Birds: Less Common Than You Might Think

Although people often imagine snakes feeding mainly on rodents, mammals make up a smaller proportion of the diet for many Australian snakes, particularly in arid and semi-arid regions.

Birds are eaten even less frequently. Birds are fast, alert, and difficult to catch. Only a few snake species — such as tree-dwelling snakes — regularly take birds or nestlings, and even then they form a small part of the overall diet.

Do Snakes Eat Insects?

Generally, no. Insects are rarely eaten directly by Australian snakes.

When insect remains are found in a snake’s stomach, they are almost always secondary prey — meaning the insect was eaten by a frog or lizard, which was then eaten by the snake.

Size Matters: How Diet Changes as Snakes Grow

As snakes grow, their diet often changes. Young snakes usually eat:

• Small lizards

• Juvenile frogs

• Occasionally small snakes

Larger snakes can take:

• Bigger lizards

• Adult frogs

• Small mammals

• Other snakes

This size-based shift reduces competition between young and adult snakes of the same species.

How Scientists Study Snake Diets

Historically, scientists studied snake diets by examining stomach contents. Today, this is done more ethically using:

• Faecal analysis

• Observations of feeding in the wild

• Examination of preserved museum specimens

Because prey is swallowed whole, it is often possible to identify what a snake has eaten even after digestion has begun.

In Summary

Australian snakes eat what their environment provides. Because Australia has:

• Few small mammals

• Unpredictable rainfall

• Extremely high reptile diversity

…snakes here rely more heavily on lizards, frogs, and other reptiles than snakes in many other parts of the world.

Their diets are practical, energy-efficient, and shaped by millions of years of adaptation to Australian conditions.

Credit and Acknowledgement

This article is adapted and simplified from the work and observations of Professor Rick Shine, one of Australia’s leading herpetologists, whose research on snake ecology, behaviour, and evolution has greatly shaped our understanding of Australian reptiles.