The African dwarf crocodile has a body covered with tough scales, called osteoderms to help defend against predation. There scales are coloured black or a grayish-black across the top part of the body. On their underside the scales are yellowish and patterned with dark lines and spots.Their head tapers slightly at the snout which is blunt.
As an adaptation to help with breathing when swimming the nostrils sit on top of the snout and the eyes sit on top of the head so they can have these above the water without exposing their whole body. The ear can be covered by a flap. They have a nictitating membrane which is a clear covering that comes down over the eye when swimming so they can see.
An African dwarf crocodile has webbed feet with five claws on the front foot and four on the back.
They are one of the world’s smallest crocodiles reaching an adult length of 1.8m (5.9ft). They weigh 80kg (176lbs).
The African dwarf crocodile is a carnivore. Their food preference changes seasonally with fish being favored in the wet season and crustaceans during the dry season. During the dry season their food intake will decrease. These foods are eaten along with frogs, insects, water birds and small mammals.
Africa is the native home of the African dwarf crocodile. Here they can be found throughout Angola, Benin, Burkina Faso, Cameroon, Central African Republic, Congo, The Democratic Republic of the Congo, Côte d’Ivoire, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Nigeria, Senegal, Sierra Leone and Togo. They may also be present in Uganda.
They make their home in the rainforest and mangrove swamps. Most of their time is spent in pools, slow moving rivers, streams and swamps. In a small portion of their range they can be found in savanna pools.
Breeding season begins at the start of the wet season as water levels rise and food becomes more plentiful. They become territorial at this time and use their senses to find a mate.
Once pairs find a mate they will lie alongside each other and begin to rub their throat gland over the other’s head. Mating is short and the male leaves once it is complete.
Following a successful mating the female will create a mound of soil and vegetation in to which they can deposit up to 10 eggs.
The mother remains with the nest until the eggs have hatched eating infrequently during this time. The young crocodiles free themselves from the egg using their egg tooth on their nose. After they hatch she will take the young to the water and care for them as they grow. Incubation lasts for 85-105 days.
At hatching the young crocodiles are patterned with lighter colours which fade to the dark adult colouration as they grow. This colouring is an adaptation to help them blend in with the shadows at the rivers edge.
Prior to hatching the eggs can easily succumb to predation from mongooses, reptiles and ants. Once they hatch large fish and birds will also prey upon them.
Sexual maturity appears to be tied to size more than age but is typically reached around 5-6 years.
These crocodiles seek shelter in burrows or under the roots of submerged trees during the day. They are nocturnal and emerge at night to hunt.
Most of their time is spent in the water. They only bask infrequently. Out of the water they are able climbers and will sometimes be seen climbing in to the low branches of the trees.
They can live in waters with some salt content due to a gland in their tongue which is used to remove excess salt from the body.
Predators and Threats
Young African dwarf crocodiles have many predators as listed above but the main threat to an adult crocodile is humans. They hunt them for food and disrupt their habitat.
They are a valuable food source for the bush meat trade as they provide one of the best returns in the area where they live.
Their leather is of poor quality and as such is not targeted like that of some other crocodilian species.
A group of African dwarf crocodiles would be known as a ‘bask.’
They are one of the smallest crocodile species.
By Ryan E. Poplin – originally posted to Flickr as West African Dwarf Crocodile #5, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=7622712
By Meganlao – Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=64201607
Burnie, D., 2011. Animal. 3rd ed. London: DK
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