Common Newt (Lissotriton Vulgaris)

2023 Author: Molly Page | [email protected]. Last modified: 2023-11-27 22:49

The common newt, or smooth newt (Lissotriton vulgaris), is one of the smallest newts. Adult newts usually grow no more than 8-12 cm. During the breeding season, the male grows a ridge - an additional respiratory organ. In spring and during the breeding season, it lives in shallow stagnant water bodies with rich vegetation of deciduous and mixed forests. After breeding, it moves to moist shady forests in the forest floor …

Area

Western Europe (except Spain and southern France), Western Siberia (reaches Altai), southern Sweden and Karelia, the North Caucasus. The mountains rise up to 1200-1500 m above sea level.

Appearance

The common newt is one of the smallest newts. 9 subspecies are known. The skin is smooth or fine-grained. Distinguishes between red, blue-green and yellow colors. The vomer teeth are arranged in parallel lines, converging slightly behind. A dark longitudinal stripe passes through the eye. The tail is slightly shorter, equal to or slightly longer than the body with the head. An adult newt sheds once a week. The body of the male is covered with large dark spots (throughout the year), which are absent in females. During the breeding season, the male grows a crest - an additional respiratory organ. The ridge is richly supplied with blood vessels, which significantly increases the proportion of cutaneous respiration. The crest of the newt is solid, with slight bends at the top; an orange border and a blue stripe pass from below. The comb does not develop in the female. The experience gained is used throughout life. The sense of smell is well developed: the number of receptor cells per cm² olfactory lining reaches 200,000. Related

article The content of the common newt (Lissotriton vulgaris)

Color

The back is painted in olive-brown tones, the lower body is yellow with small dark spots. There are longitudinal dark stripes on the head. An ordinary newt can change color - it becomes darker and lighter.

Dimensions

Newts usually grow up to 8-12 cm.

Life span

In captivity, these amphibians live up to 20-28 years.

Vote

An ordinary newt is capable of producing sounds at a frequency of 3000-4000 Hz, the duration of which does not exceed 0.5 s.

Habitat

In spring and during the breeding season, the common newt lives in shallow stagnant water bodies with rich vegetation (pH 5.6-7.8) of deciduous and mixed forests. It preserves at a depth of 5-50 cm. After breeding, it moves to moist shady forests in the forest floor. Sometimes found at a distance of up to 300 m from the nearest body of water. Does not live in overgrown swamps with low oxygen content and lack of open water.

Enemies

Enemies of newts include snakes, vipers, storks, ducks, herons, crested newt, frogs, garlic, water voles, bedbugs, fish, larvae of the swimming beetle and dragonflies.

Nutrition / food

In the water, the common newt hunts for mosquito larvae, small crustaceans, molluscs, insects, grass frog larvae, sometimes toad tadpoles, fish eggs, shrimps, and water snails. On the ground, it eats earthworms, centipedes, beetles, butterflies, caterpillars, shell mites, spiders and other invertebrates. The stomach of a newt, while it lives in water, is 70-90% full, and on land - 65%.

Behavior

Triton leaves water in the middle of summer. On the shore it is nocturnal. Does not like light, sun and heat. During the day, it hides in the forest floor, under stumps, dead wood, stones, woodpiles of firewood, etc. Sometimes in such places you can find several individuals at once. Avoids large open spaces. During daylight hours, it can be seen only in rainy weather or during the breeding season (when it migrates to water bodies). In water, the newt is active at any time of the day; it floats to the water surface for air every 6 minutes. Wintering lasts from October to March. Loses mobility at temperatures around 0 ° C. It hibernates in holes of voles and moles, in heaps of fallen leaves, cellars and basements, sometimes accumulating up to several hundred individuals together. Usually the distance from the reservoir to the wintering site does not exceed 50-100 m.

Larva

Reproduction

The common newt begins with a search for a suitable reservoir. For this purpose, a large shallow water body with rich vegetation is suitable (stagnant or weak-flowing lakes, ponds, quarries, oxbows of rivers, streams, peat or sedge bogs, pits filled with water, ditches, deep ruts of country roads) located in glades, forest edges or among thickets of bushes. The water in the reservoir should warm up to + 6 ° C, after which mating games begin in newts. All meetings and partings take place in silence. During this period, in males, in addition to the crest, lobed edges appear on the fingers. They, like the ridges, are abundantly supplied with capillaries, and also serve to improve skin respiration in water. The male of the common newt lays spermatophores, which the female picks up with her cloaca. Fertilization is internal. After mating games, female newts spawn alone. Each female can lay 60-700 eggs (egg diameter 3-3.5 mm with a shell and 1.5-2 mm without a shell), attaching them one by one to the leaves of underwater plants. The process of laying eggs lasts from several days to three weeks (depending on the temperature of the water). Eggs are laid at a depth of 5-35 cm, sometimes deeper. The ratio of the number of females to the number of males can be 5: 1, and sometimes 10: 1. In nesting places among females there are often cases of eating eggs of other females. The ratio of the number of females to the number of males can be 5: 1, and sometimes 10: 1. In nesting places among females there are often cases of eating eggs of other females. The ratio of the number of females to the number of males can be 5: 1, and sometimes 10: 1. In nesting places among females there are often cases of eating eggs of other females.

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Breeding period

The breeding season is between March and June.

Puberty

Ripening occurs in the 2-3rd year of life.

Courtship ritual

The male is waiting for the female in the reservoir. When a female appears, he approaches her, swims up close, touches her muzzle, and sniffs. Making sure that the female is in front of him, the male begins his dance. He moves forward and, finding himself in front of the female's muzzle, makes a stand. For about ten seconds, the male stands at the bottom upside down, raising his body high and leaning only on his front paws. This is followed by a jerk, the male's head remains almost in the same place where it was, the body drops, the tail bends strongly and pushes the water directly onto the female. The male newt takes a break, and then, standing in front of the female, bends his tail and quickly hits it on his own. Further, he stands, and the tip of his tail wriggles. The female begins to walk slowly forward, the male follows her.

Female

Incubation

Egg incubation lasts 14-20 days.

Development

Newborn larvae are 6-8 millimeters in size. The color is light, almost monochromatic, with rounded light spots on the sides, the back is yellowish or light reddish-yellow. They have a distinctly pronounced tail, which is surrounded by a fin fold, there are primordia of the forelimbs and feathery external gills. The first days of life, newt larvae breathe with gills, and by the end of the larval period they switch to pulmonary respiration. The gills disappear in the course of metamorphosis. There are no suction cups, and on the sides of the head there are glandular outgrowths - balancers, which quickly disappear.

The rudiments of the hind limbs appear on the 20th day of life. The development of the larvae lasts 2-3 months. The first hours of the larva are inactive. By the end of the first day of life, they have a mouth gap, and on the second day, the mouth breaks out, and the larvae begin to actively feed. Larvae begin to perceive olfactory stimuli on the third day of life. From the fourth day, the olfactory stimulus can cause fright in the larvae, and from the 9th-12th day they begin to use the sense of smell to search for food. The larvae hunt, hiding in the thickets, with a sharp throw they rush to the prey (small crustaceans and mosquito larvae) with their mouths wide open. At the larval stage, mortality is maximum. Complete metamorphosis occurs in 60-70 days. The length of young newts when they come to land is 3-4 cm, at this moment their gills and fin fold disappear. Underyearlings after metamorphosis hunt only on land.

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Benefit / harm to humans

Both larvae and adult newts destroy mosquitoes, including malaria.

Population / conservation status

The common newt is listed in the Red Book of Russia and Azerbaijan. A rare species in the UK. Included in the Berne Convention (Appendix III). On land, it occurs as single individuals, in water bodies the number is 0.016-16000 individuals / ha; in some places it reaches up to 110 individuals / m ^{3 of} water.

Interesting: the skin secretions of the newt are caustic, but the poison is not dangerous for humans. For warm-blooded animals, the lethal dose is 7 mg per 1 kg of body weight. The poison causes an increase in blood pressure, destruction of red blood cells and the formation of blood clots, in severe cases, paralysis occurs, breathing stops, the heartbeat turns and the animal dies.