Skip to content

Olm Salamander » Characteristics, Feeding and Reproduction

The waters with karstic limestone rocks of Europe are one of the places where one of the rarest animals, the Olm, lives, a species of amphibian very little known by man. At first glance, what is most striking is its undeveloped eyes and strange skin.

Main characteristics of the Olm Salamander

This strange amphibian receives the scientific name of Proteus anguinus and belongs to the numerous family Proteidae.

The Olm is a salamander that has peculiarities that make it a wonderful and unique amphibian.

When we talk about the Olm salamander we must know that we are in front of an animal that does not possess the sense of sight, because its eyes did not evolve.

But, to compensate this deficiency they are forced to sharpen other senses such as smell and hearing.

Among its physical characteristics, the first thing that calls our attention is its skin that does not possess pigmentation, but rather is fleshy in appearance, which is why it is called “human fish”.

Because of its colorless skin, we can clearly see its internal organs in the abdominal area.

Like other amphibians, this special animal presents neoteny, which causes a delay in its development, as a consequence it maintains larval characteristics even in adulthood.

The size of the Olm salamander can vary, these animals can reach 20 to 30 cm in length.

But, in some special cases, specimens of up to 40 cm have been found.

In this species there is sexual dimorphism, therefore of both sexes the one that grows the most is the female.

Its head has a strange pear shape and is provided with an obviously short and flattened snout.

Laterally there are its nostrils which are almost impossible to appreciate for the human eye.

In addition, the back of its head has gills that look like two branched locks.

These cutest rare animals have a life span of about 60 years, but some species have managed to reach 70 years.

Natural and Geographical habitat of the Olm

This rare amphibian is a completely aquatic animal and is geographically distributed in some areas of Slovenia, Italy, Croatia and Bosnia-Herzegovina.

This creature lives in caves where total darkness reigns, waters where the temperature ranges from 5ºC to 15ºC and the Karstic limestone rocks of central and southeastern Europe prevail, where these animals originate, specifically from the Soca River.

We must take into account that the Olm is a sensitive animal so it is necessary for it to inhabit clean waters, which is why pollution becomes its worst threat.

What does the Olm feed on?

This animal has perfectly developed other senses that allow it to function in its environment, which is why it has the capacity to perceive the agglomeration of organisms.

It can also detect the quality and quantity of its prey by simply using its olfactory sense.

If at any time this impressive animal goes through conditions where food is scarce, it can remain up to 6 years without eating absolutely anything, maintaining itself only by reabsorbing its tissues.

The Elm’s diet consists of worms and crustaceans which it hunts in the darkness of the deep.

How does the Olm reproduce?

These amphibians are suitable for their reproductive process once they reach sexual maturity, which occurs after 14 years of age.

The courtship is initiated by the male, who is responsible for chasing away the other males in the area and secreting pheromones to call the opposite sex. The female answers the call, he surrounds her and throws her with his thin tail.

From this moment on, the contact between male and female begins. The latter begins to touch the animal’s morphology with its muzzle and the female corresponds by touching its cloaca.

At this point they mate until the male deposits his sperm, and the act ends when the female hits him with her cloaca.

The period of embryonic development will depend directly on the temperature of the water, the warmer the water the shorter the time.

The female usually lays about 70 eggs, which she attaches to the rocks. She stays to guard them from predators.

Once these eggs hatch, the young come out measuring 12 cm.

However, some cases have been observed where the eggs are retained inside the female’s body and two formed hatchlings are produced.

We must take into account that the Elm does not go through any transformation, so it will always preserve its larval characteristics.