Nocturnal Animals What is a Nocturnal Animal?

The possum is a nocturnal (night-time) animal

Photo: The possum is a nocturnal (night-time) animal

A nocturnal animal is active at night and sleeps during the day. However, some animals that appear to be nocturnal may also be active during the day.

Animals, such as possums and owls, are strictly nocturnal. They only come out in total darkness. Kangaroos are classified as nocturnal, but they are also crepuscular, being most active during dawn and dusk.

Elephants and the red fox are predominately active during dawn and dusk, but they are also active at night. Echidnas, on the other hand, vary the times they are active according to their environment. For example, if the climate is hot, the echidna will forage for food at night. But in cooler weather, it will come out during the day. While the echidna's behaviour is dictated by its desire to stay cool, it is just the opposite with some snakes, such as the red-bellied black snake. Being cold-blooded and needing to keep warm, these snakes will hunt at night if the weather is hot. But if the weather is cold, they will only do so during the day.

So, the term nocturnal is used quite broadly to describe a group of animals that are usually active when it is dark.

• List of Nocturnal Animals


Time of the Day Animals are Active? Day, Evening, Night or Undecided

There is often confusion as to whether an animal is nocturnal or not. This is because some of these animals may seem to be active during other times of the day.

Animals have been categorised into three broad groups based on the time of day that they are most active.

Photo: Times of day chart

Diurnal (Daylight ) animals are usually active during daylight and rest when it gets dark.

Crepuscular (Twilight) animals are active during dawn and dusk (twilight) and rest at other times of the day.

Nocturnal (Night) animals are active during the night when it's totally dark and rest during other times of the day. Most mammals (69%) are nocturnal.

Many animals, however, don't fit conveniently into these categories as they may be seen to be active across these time zones and may adjust their behaviour to several factors – typically the climate.

It is common practice to classify many animals that come out when it gets dark as nocturnal, even though they may actually be crepuscular animals. One reason might be the tongue-twisting name – crepuscular – which few can remember or pronounce.


Why are Animals Nocturnal? Why Does Australia have so many Nocturnal Animals?

Its Cooler at Night

Most nocturnal animals live in arid environments such as deserts. Take Australia, for example. It is the driest inhabited continent on earth. Most of the land is dry, and the climate is hot. As a result, many Australian animals, especially the marsupials, have adopted a nocturnal lifestyle to avoid the blistering daytime heat. This behaviour of coming out at night when the temperature is cooler conserves precious water lost.

Its Easier to Avoid Detection at Night

Many animals use the cover of darkness to evade predators. However, it should be noted that many predators are nocturnal too, and use the darkness to hide themselves and ambush their prey.

Competition

Some animals have adopted night-time behaviour to minimise competition for food. For example, the hawk and owl hunt in similar environments and for similar prey, but one hunts during the day and the other hunts at night. In this way, they minimise competition between each other.


Nocturnal Animal Adaptations Special Characteristics of Animals of the Night

Nocturnal animals have evolved special adaptations that help them survive in the dark.

Eyes (Sight)

Animals such as owls, possums and cats have excellent low-light eyesight.

Ears (Sound)

Photo: The bilby has big ears and nose

The kangaroo, bilby, and rabbit have an acute sense of hearing. This allows them to detect danger at great distances in the dark. Many bats use echolocation which acts like a radar. The bat emits a high-frequency sound that bounces off objects, and the animal's ears pick up the bounced signals to help it navigate through the dark.

Nose (Smell)

Some animals have an acute sense of smell. Koalas with their large noses and elephants with their sensitive trunks, for example, can sniff out the most appropriate leaves to eat in the dark.


Australian Nocturnal Animals Why are Most Australian Animals Nocturnal?

Most Australian animals are nocturnal and crepuscular. That is, they are only active when its dark. Australia is arid with very little water, and the climate is hot. As a result, many Australian animals, especially the marsupials, have adopted a nocturnal lifestyle to avoid the blistering daytime heat. This behaviour of coming out only at night when the temperature is cooler conserves precious water lost.


List of Nocturnal Animals

 


Owl

Owls have round flat faces with prominent eyes. Most are crepuscular, being active at dawn and dusk.

 

House Gecko

The house gecko is active after dark and forages of insects at night. It is fond of cohabiting with humans in houses and buildings.

 

Rat

Black and brown rats are crepuscular and nocturnal but will come out during the day if there is food and its safe to do so. There were no rats in Australia until the arrival of the first Europeans. They arrived in Australia as stowaways.

 

Feral Pig

Feral Pigs are the descendants of pigs brought to Australia by European settlers that became wild. They are primarily nocturnal.

 

Red-eyed Tree Frog

Red-eye tree frogs live in rainforests and wetlands. They are nocturnal hunters that feed on moths and other insects. They make a 'waa-aa' sound.

 

Rakali (Water Rat)

The Rakali is a semi-aquatic placental that is mostly nocturnal but starts searching for food at dusk. It lives in burrows on the banks of waterways.

 

Taipan

Taipans are large venomous snakes. They are usually active during the day, but in hot weather they may become nocturnal.

 

Gastric-brooding Frog

Gastric-brooding frogs incubated their eggs in the mother's stomach and kept their young in her mouth. They are extinct. They were nocturnal.

 

Eastern Bettong

The eastern bettong became extinct on mainland Australia. A very small population still exists in Tasmania. They are nocturnal.

 

Plains Wanderer

Plains Wanderers are small quail-like birds that prefer to run rather than fly and fall prey to foxes. Although it is a diurnal feeder, it is only seen at night.