Words and photos by Tracey Bruton (except for scops owl in tree photo: Neil Coetzer & common diadem photo: Thomas Botha)
One of the most amazing techniques for survival in the wild is camouflage. Animals have the ability to mimic plants, ground cover, or even other animals in order to hide or hunt.
Camouflage is a colouration or pattern that helps an animal blend in with its surroundings. Animals use various types of camouflage to hide themselves from predators, as well as for predators to hide themselves from potential prey!
There are several different types of camouflage, including concealing colouration, disruptive colouration, disguise, mimicry and counter-shading. Some creatures use more than one type.
We will also look at aposematic colouration, which is not a form of camouflage, but is also a tactic to avoid being eaten.
This type is when the colour of the animal matches the colour of the background, as in the ground colour or vegetation that it finds itself. This is the most common form of camouflage. When mottled, it is also known as ‘cryptic colouration’. Examples of these are lions, many antelope species and chameleons.
Lions are examples of fixed camouflage. Their tawny coats help them to blend in to the colours of their savanna habitat. Chameleons have active camouflage- they are able to alter their colouration at will based on where they are (as well as for other reasons, such as mood or stress). Some animals have a seasonal camouflage, which allows the animal to match to its environment at the time, such as the Arctic fox changing from its summer brown colour to its winter white colour to match the winter snow in their habitat.
Chameleons are able to change the colour of their bodies. They do this for several reasons, the first to hide from predators and to be concealed in order to creep closer to insect prey. They also change colour according to mood, temperature and other environmental conditions, and to communicate with and display to other chameleons.
They are able to change colours quickly by sending cues by their eyes on their environment. Pigments are mixed within special skin cells called chromatophores, and the distribution of different pigment granules results in the specific colour needed.
Brighter colours are used when interacting with other chameleons, they turn lighter in hot conditions to reflect more heat, and darker when they are cold or angry.
Counter-shading is a type of concealing colouration used by animals with a darker upper half, and a lighter lower half. This makes the animal appear more one-dimensional and flatter against the background, but also conceals the animal when viewed from above or below. The darker back matches the dark ground when viewed from above, and the lighter belly will match the lighter sky when viewed from below.
The best examples of this is impala, many snakes, fish and water birds. Other examples in other parts of the world include penguins, sharks and whales.
With fish, when viewed by aerial predators from above, their dark shading on the upper half of their body makes them almost invisible against the dark, shady depths, whereas a lighter lower body also renders them less visible to predators approaching from below, against the lighter sky.
In addition to background matching colouration, many animals also have distinctive designs on their bodies to help to conceal them. Spots, stripes or other patterns break up the outline of its body so blending the animal into its environment. The shape of the animal is broken up so that it is almost invisible until it moves!
Most mammals only see in black and white, so disruptive camouflage is really successful for many prey animals and predators.
Examples of disruptive colouration are leopard, cheetah, kudu, zebra, and many ground- living birds and reptiles.
Animals that live in groups use different camouflage tactics to those that live alone.
Zebra, which form herds, have very unique black and white stripes. These stripes are not meant to camouflage them into the environment, but rather to confuse the predator and create a dazzle of stripes – thus their collective name! When a herd of zebra is disturbed by a predator, they clump together and run as a group, and with their stripes creating a confusing black and white mass, it is difficult for the predator to pick one target. This is especially true for zebra foals, which stay close to their mother’s sides for the first year of their lives. They also have very long legs from a young age, which of course allows them to keep up with the herd when running from danger, but also camouflages the foal against his mother as both their bellies are at the same height!
Leopards are masters of camouflage. They mostly live in areas where there are patches of light and shadow. Having a solid colour, they would really stand out, but their rosetted coat breaks up their body outline, making them less obvious. Their camouflage is to hide their presence from enemies (such as lions, hyenas and other leopards), but also to hide them from prey. Being solitary hunters, leopards have to sneak up to within about 10m (32ft) of their prey before they pounce. Being a highly adaptive cat living in many different habitats from outskirts of cities to forests, leopards are able to blend in to almost any habitat.
Disguise and mimicry are very similar, however with disguise, the animal copies a non-living thing such as a leaf or twig, and with mimicry, it copies another living animal. The animal disguises itself in form and in colour to look like an object within its environment.
Mimicry is the tactic of an animal copying another animal in form and/or colour. It may not seem like a form of camouflage, but it is still a way to avoid detection or to avoid being eaten by fooling the predator!
Some creatures pretend that they are dangerous by mimicking the look of a venomous, poisonous or dangerous animal. An example is the common diadem butterfly, which is not poisonous, that looks very similar to the African monarch butterfly, which is poisonous. This is known as Batesian mimicry.
When two unrelated species that are both poisonous, venomous, distasteful or dangerous mimic each other, this is called Müllerian mimicry. This tactic is meant to reinforce the message of danger to predators. Examples of this are Acrea butterflies, bees, wasps and some frogs and snakes.
Some birds, invertebrates, fish and reptiles have developed an ‘eye spot’. This is an eye-like marking where this spot on the body resembles false eyes of the creature, or even eyes of a bigger, more ferocious creature, in order to make a predator think twice before attacking it. The false eye may draw the predators attention away from more vulnerable body parts, or appear as an inedible or dangerous animal. Eyespots may also play a role in communication within that species or courtship, as in the eyespots on a male peacocks display feathers.
Aposematic colouration is the advertising by an animal to a predator that it is not worth attacking. This may be due to toxins, venom, a foul taste or smell, sharp spines or an aggressive nature. The warning signal is either with bright colours, or black and white patterns.
Most of the creatures that are brightly coloured are invertebrates, and the group of creatures that mostly eat them are birds. Both of these groups see in vivid colour. Mammals, however, do not see in colour, therefore that is why you do not see brightly coloured antelope walking around in the savanna, but rather many vividly coloured invertebrates, as well as many birds, reptiles, amphibians and fish.
Rather than hiding themselves, some animals use bright warning colouration to signal to would-be predators that they are poisonous or contain venom. The idea is to be seen in order to be avoided.
Invertebrates mostly display aposematic colouration using black with red, orange or yellow to display during the day when it is light. A few examples of these are many butterflies, bees, some grasshoppers and frogs.
At night, bright colours cannot be seen, and the most visual warning colouration (especially to animals that are colourblind anyway) is black and white. Examples are honey badgers, civets, polecats and porcupines. The former creatures have noxious fluids that they can spray in defence, and porcupines have dangerous sharp quills.
In all natural areas around the world, you will see all sorts of variations and combinations on the basic elements of camouflage. Often, these adaptations are more effective than a more aggressive approach using teeth, claws or beaks. After all, being completely overlooked by a predator is better than having to put up a fight!