Amphibians fact sheet | Field of Mars EEC

What are amphibians?

Amphibians are vertebrate animals, which means they have a backbone. They belong to a group of animals called Amphibia and are related to other vertebrates such as birds, mammals, reptiles and fish. In Australia, the native amphibians students are most likely to learn about are frogs.

Australia’s native amphibians are frogs, and frogs are the only remaining amphibians in Australia. They have moist skin, no scales, and most lay soft jelly-like eggs in water. Many amphibians begin life as tadpoles before changing into adults.

Amphibians can be found in many places around Sydney, including creeks, ponds, wetlands, bushland, parks, gardens and school grounds. Around Lane Cove National Park, Field of Mars Reserve and greater Sydney, students may hear or see frogs such as Peron’s tree frogs, striped marsh frogs, common eastern froglets, eastern dwarf tree frogs and green stream frogs.

Peron’s tree frogs are common Sydney frogs often heard calling from trees, shrubs and wet areas at night.

Striped marsh frogs are common around ponds, wetlands and drains in Sydney.

How do you know it is an amphibian?

Amphibians usually have moist skin and no scales, feathers or fur. Most species need damp places to survive because their skin can lose water easily.

Frogs are the amphibians students are most likely to find in Sydney. They usually have large eyes, strong back legs and no tail as adults. Some frogs climb with sticky toe pads, while others live close to the ground, hide in leaf litter or shelter near water.

Many amphibians begin life in water as tadpoles. Tadpoles have tails and breathe through gills. As they grow, they develop legs, lungs and the body shape of an adult frog.

Striped marsh frogs lay floating foam nests where tadpoles can develop in shallow water.

Amphibian groups

Tree frogs

Tree frogs often have sticky toe pads that help them climb leaves, branches, rocks, bark and smooth surfaces. Many tree frogs call at night from vegetation near water.

Peron’s tree frogs and eastern dwarf tree frogs are examples of tree frogs that may be found around Sydney. Peron’s tree frogs are often heard calling from trees and buildings after rain.

Blue Mountains tree frogs live near creeks and wet forests in parts of the Sydney region.

Ground frogs

Many frogs spend most of their time on or near the ground. They may shelter in grass, leaf litter, soil cracks, logs or vegetation near ponds and creeks.

Striped marsh frogs and eastern banjo frogs are ground-dwelling frogs. Striped marsh frogs are common around ponds, drains and wetlands, while banjo frogs are often heard after rain in damp places.

Ground frogs often shelter in damp soil, grass, leaf litter or vegetation near water.

Froglets

Froglets are small frogs that can be difficult to see but easy to hear. The common eastern froglet is one of the most widespread frogs in south-eastern Australia.

Common eastern froglets may call from shallow water, wet grass, drains, ponds, creeks and damp areas after rain. Their colours can vary, which means their call is often a useful way to identify them.

Common eastern froglets are small frogs that are often heard before they are seen.

Stream frogs

Some frogs live close to flowing water such as creeks and rocky streams. They need healthy streamside vegetation, clean water and places to shelter.

Green stream frogs are found in parts of the Sydney region. They are usually associated with creeks and wet vegetation.

Green stream frogs live near creeks and other damp, vegetated places.

Wetland frogs

Wetlands, ponds, swamps and dams provide important breeding places for many frogs. Some frogs lay eggs in floating foam nests, while others lay jelly-like eggs among plants or shallow water.

Wetland frogs may feed on insects and other small animals found near water. Their tadpoles grow in ponds, pools, drains or slow-moving waterways.

Eastern dwarf tree frogs often shelter and breed among reeds and wetland plants.

What is the life cycle of amphibians?

Most frogs hatch from eggs laid in water or damp places. Frog eggs are usually soft and jelly-like rather than hard-shelled.

Tadpoles hatch from the eggs and live in water. They breathe through gills and swim with tails. As they grow, tadpoles develop back legs, then front legs. Their lungs develop and their tails shrink.

Young frogs leave the water when they are ready. Adult frogs return to suitable wet places to call, find mates and lay eggs.

Some frogs lay eggs in floating foam nests that protect developing eggs.

What adaptations do amphibians have to help them survive?

Amphibians have many adaptations. Moist skin helps them absorb water and exchange gases. Many frogs have camouflage colours that help them hide among leaves, bark, rocks, mud or grass.

Different frogs have different feet and legs. Tree frogs have toe pads for climbing. Ground frogs have strong legs for hopping or digging. Stream frogs may have body shapes and behaviours that help them live near flowing water.

Many frogs use calls, night-time activity, hiding behaviour and rapid jumping to survive. Some call loudly after rain when there is enough water for breeding.

Moist skin, camouflage, strong legs and toe pads are important frog adaptations.

Why are amphibians important?

Amphibians are essential in healthy ecosystems. Adult frogs eat insects and other small invertebrates. Tadpoles can feed on algae, plant material and tiny organisms in water.

They are also food for other animals, including birds, reptiles, fish, mammals and larger invertebrates. Without amphibians, many food webs would not work properly.

Amphibians can also tell us about the health of an environment. Because many species need clean water and damp shelter, changes in frog numbers or diversity may show that a habitat is changing.

Frogs help food webs by eating small animals and providing food for predators.

How can you help amphibians?

You can help amphibians by protecting habitat. Leave logs, leaf litter, rocks, grasses, reeds and shrubs where it is safe to do so. These places provide shelter, food and damp spaces for many frogs.

Plant local native plants around ponds, creeks and wet areas to provide shade, shelter and insects for frogs to eat. Avoid removing all vegetation from the edges of ponds or waterways.

Keep waterways clean, place rubbish in bins and avoid unnecessary pesticide or chemical use. Pesticides can reduce the insects frogs need for food and may wash into waterways.

Keep cats contained and avoid moving frogs, tadpoles or frog eggs between places. Moving amphibians can spread disease or place them in unsuitable habitat.

Clean water, native plants and shelter can help support frogs in gardens, schools and reserves.

Explore more

Use the fact sheet links on this page to learn more about amphibians and other animals found in bushland, gardens, wetlands and school grounds.

You can also compare amphibians with other vertebrate groups such as birds, reptiles and mammals.

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