The spiny newt (Pleurodeles waltl) is a species of amphibians belonging to the genus Ribbed newts from the order Tailed amphibians. The spiny newt belongs to one of the largest species of newts, the most important feature of which is the pointed ends of the costal bones that stick out on the sides at the moment of danger. The thing is that poison is released at the ends of the ribs, causing unpleasant sensations in the predator and forcing him to leave his prey alone. This is where the name came from.
View origin and description
Photo: Spiny Newt
Spiny newts and other types of newts are very ancient amphibians, once very widespread. Over time, the glaciers of the Quaternary period pushed them to the southern and western parts of Europe. Today, this species lives in a very limited area where it is officially recognized as endemic.
Video: Spiny newt
These are relatively large animals that under natural conditions can grow up to 23 cm in length, while in captivity their length can reach 30 cm or even more. Females, as a rule, are larger in size than males, but do not differ from them in any other way. Spiny newts do not have a dorsal crest. Their tail is rather short – about half the length, flattened, trimmed with fin folds, and rounded at the end.
The skin has a dark brown or almost black color with lighter blurry spots. To the touch it is uneven, very granular, bumpy and glandular. On the sides of the body there are a number of reddish or yellow spots. It is in these places that the sharp ends of the triton's ribs protrude in case of danger. The abdomen of amphibians is lighter, grayish in color and has small dark spots.
Interesting fact: In captivity, an albino form of spiny newts was recently bred — with a white back, white-yellow belly and red eyes.
Appearance and Features
Photo: Spanish Spiny Newt
Newts have skin smooth and shiny while they are in the water. When animals go on land to breathe or hunt, their skin is severely dehydrated, becoming rough, rough and dull. The head of amphibians is similar to that of a frog with small, bulging golden eyes located on the sides.
Due to the many glandular dorsal growths, the body of spiny newts looks square when viewed across. The skeleton of animals has 56 vertebrae. In addition to the sharp ribs that protrude outward to break through the skin in defense, there are many venom glands throughout the newt's body. The poison of spiny newts is weak and not lethal, but when it hits the scratches on the mucous membranes of the enemy, caused by the newt's sharp costal bones, it causes pain to the predator.
Fun fact: Cloacal lips females are very developed, while males are hypertrophied.
Now you know what a spiny newt looks like. Let's find out where it lives.
Where does the spiny newt live?
Photo: Spiny newt in Spain
The homeland of the ribbed newt is Portugal (western part), Spain (southwestern part) and Morocco (northern part). Tritons live mainly in reservoirs with cool fresh water. Rarely found in the mountains of Granada (Sierra di Loggia) at an altitude of up to 1200 m. They can also be found at a depth of 60-70 m in caves near Bukhot or Ben Slayman in Morocco. The Spanish spiny newt lives at a depth of up to 1 m in slow-flowing water bodies: in ditches, ponds, lakes.
Interesting fact: Not so long ago, Swedish biologists deciphered the genome of the spiny newt. As a result of the research, it was found that the animal DNA code contains several times more genetic information than the human DNA code. In addition, newts have the largest regenerative repertoire of all tetrapods. They can regrow as well as rearrange their tails, limbs, jaws, heart muscle, and even brain cells. The next stage of the research will be a detailed study of the work of brain cell regeneration and exactly how stem cells are involved in the regenerative processes of adult newts.
The purity of water for these amphibians is not fundamental. They also do well in slightly saline waters. The Spanish newt can lead both aquatic and terrestrial lifestyles, however, it prefers the former more, so it is rarely seen on land. Spiny newts usually live in the same body of water for several years, or even their entire lives. If for some reason the habitat is no longer suitable for them, then they migrate in search of a new home, and they do it during the rain to avoid dehydration. In summer, in extreme heat, during a very dry period, amphibians can leave water bodies and hide in deep burrows and crevices between stones. At this time, newts are very difficult to spot, as they come to the surface at night and only to hunt.
What does the spiny newt eat?
Photo: Spiny newt from the Red Book
Spiny newts are real predators, but they are not special gourmets in food, so they can eat everything. The main condition: their potential food must fly, run or crawl, that is, be alive. In eating, they fell even under very unfavorable conditions, newts were not noticed, but cases of cannibalism, especially in captivity, happened.
The daily menu of amphibians looks something like this:
- molluscs;
- worms;
- small invertebrates;
- insects;
- young snakes.
In the summer, when it is very hot even in the water and the newts are forced to hide from the heat, they easily endure short-term starvation. During the period of mating games, when the instinct of procreation comes to the fore and becomes stronger than other needs, amphibians also eat practically nothing, but constantly fight with rivals, care for females, mate, and spawn.
In captivity, spiny newts also prefer to eat live food. Earthworms, flies, grasshoppers, snails, slugs, bloodworms, as well as pieces of raw frozen meat or fish are suitable for this. Feeding newts with dry or wet food for cats or dogs is strongly discouraged, as they contain ingredients that are completely uncharacteristic for the natural diet of newts.
Peculiarities of character and lifestyle
Photo: Spiny Newt
Ribbed newts feel good both on land and in water, but at the same time they may not go to land at all for several years. Animals' favorite pastime is to «hang» in the water column, looking around. Depending on weather conditions, they can lead both daytime and nocturnal lifestyles. For example, in the off-season, when it is not too hot, newts prefer to hunt during the day. In summer, when the air temperature is very high, newts are forced to hide in burrows and caves during the day, and go hunting at night.
Interesting fact: Spiny newts are characterized by molting. There are no clear periods of molting – everything is individual for each individual.
Newts need to shed because they breathe through their skin. It is literally permeated with thin blood vessels (capillaries), the enrichment of blood with oxygen in which occurs directly in the water. This feature allows amphibians not to often float to the surface for air. Since spiny newts are not too sensitive to the purity of the water, their skin is quickly contaminated. Contaminated skin interferes with proper respiration, which is why the newts shed it.
Interesting fact: Spiny newts can live up to 12 years in nature, and up to 8 years in captivity. Although much, if not all, depends on nutrition and conditions.
Social structure and reproduction
Photo: Spanish Spiny Newt
Spiny newts can give birth 1-2 times a year. The first breeding season falls on February-March, the second – in July-August. According to the type of their social behavior, they are solitary animals that gather in groups only during the mating season.
Puberty in amphibians occurs in the period from 1 to 3 years, which depends on their living conditions. With the beginning of the mating season, calluses grow on the paws of male newts. Why they are needed is completely unclear. Probably for protection during fights with rivals.
The mating season has the following stages:
- mating;
- courtship;
- mating;
- spawning.
During mating fights, males fight among themselves, and quite cruelly. The courtship process includes a kind of prelude to the act of mating. The male clasps the female obtained in a fair fight with his paws and for some time peculiarly «rolls» her along the bottom of the reservoir. After the foreplay, mating begins. The male touches the muzzle of the female with his paws and gently clasps her from below, at the same time releasing the seminal fluid onto the body and moving it with his free limbs to the cloaca. The mating ritual can be repeated 5-7 times.
2-3 days after mating, spawning begins. Depending on size and age, a female newt can lay up to 1,300 eggs. The eggs are fixed by the female on the leaves and stems of aquatic plants in the form of chains of 10-20 eggs, where the incubation process then takes place.
An interesting fact: The eggs of the spiny newt are up to 2 mm in diameter, while the diameter of the gelatinous envelope is not more than 7 mm.
Under favorable conditions, larvae hatch from eggs in 15-16 days. For the first few days of life, they do not need food at all. Further, the larvae feed on simple unicellular. Length of larvae — 10-11 mm. After about three months, the larvae begin the process of metamorphosis, which lasts another 2.5 — 3 months. Upon completion of the metamophysis, the larvae turn into small newts, which differ from adults only in their size.
Fun fact: Young newts can grow up to 14 cm in their first year of life
Natural enemies of spiny newts newts
Photo: Spiny newt from Spain
As mentioned earlier, spiny newts protect themselves from predators who want to hunt them with the help of ribs and a poisonous substance that is released at the ends of the costal bones in moments of danger. However, newt venom is not lethal, which often does not work in their favor. There are also cases of cannibalism among spiny newts, but they are very rare.
Since adult individuals of newts are quite large in size – up to 23 cm, they do not have so many natural enemies, but they can be hunted by large snakes that swallow their prey whole and birds of prey (eagles, hawks) that kill their prey, throwing from a height on the stones. Since spiny newts are very clumsy on the ground, they can become easy prey for herons and cranes.
As for the young, the larvae and small newts will have more enemies in nature. For example, larvae are successfully hunted by frogs and predatory fish. Moreover, the caviar of newts, containing a lot of protein, is also an excellent delicacy for toads and fish. Smaller newts are also preyed upon by smaller snakes, birds, and even quadrupeds. Zoologists have calculated that on average there are 1,000 eggs laid, half of them barely survive to sexual maturity.
Population and species status
Photo: Spiny newt
Ribbed newts, like most amphibians, are quite prolific. Moreover, they have as many as two mating seasons a year. However, even this in the modern urbanized world cannot save the situation, and today in all three countries the population of the spiny newt has greatly decreased and continues to decline.
The main reasons for the decline in the population of spiny newts:
- short life span. In the wild, a newt lives no more than 12 years. There are many reasons for this, such as natural disasters, lack of food, natural enemies;
- poor ecology, severe pollution of water bodies with waste and various chemicals. Although spiny newts are not too sensitive to not very clean water, however, with the development of industry and farming, so many harmful chemicals enter the water that even newts cannot live in it;
- geographical changes in the natural habitat. For the sake of agricultural development, swampy lands are often drained, which ultimately leads to the disappearance of water bodies where newts previously lived;
- The spiny newt is in considerable demand as a pet. Of course they are bred in captivity for sale, but the illegal capture of wild newts, especially young ones, causes simply irreparable damage to the population.
Protection of spiny newts
Photo: Spiny newt from the Red Book
As mentioned above, the population of spiny newts continues to decline due to many adverse factors, including poor environmental ecology and pollution of water bodies.
For this reason, the amphibian is listed in the Red Books of Italy, Portugal, Spain, Morocco, as well as in the International Red Book. According to statistics, in the above countries, more than half of the water bodies have been drained over the past decade, which actually led to a sharp decrease in the number of spiny newts living in natural conditions.
This fact caused serious concern among zoologists, and they believe that if everything is left as it is and no serious conservation measures are taken, then in 10-15 years there will be no spiny newts in nature at all. «But this species is successfully bred in captivity» — someone will say. Yes, but domestic newts in nature may not take root, because as a result of a comfortable life, they have lost all the necessary skills.
What needs to be done to restore the population of spiny newts in their habitat:
- strengthen penalties for illegal fishing;
- improve the environment;
- preserve water bodies;
- minimize the use of harmful chemicals on agricultural land.
The spiny newt is one of the largest members of its family. This animal is considered rare in its habitat, but as a pet it can be bought in almost every pet store. Spiny newts live both in water bodies and on land, but they still spend most of their time in the water. Today, newts require special attention, as their numbers are declining every day.
