Common midwife toad. The midwife toad is an interesting animal Interesting facts about midwife frogs

Tailless amphibians are such animals around which there are a lot of superstitions and implausible stories, and the culprit of such fictions is the ignorance of people and unwillingness to learn more about their lives. But among amphibians there are very interesting representatives. So, for example, the midwife toad, or midwife (Alytes obstetricans), attracted attention thanks to an unusual way of caring for their offspring.

Midwives are small toads with a relatively large head. Adults of both sexes reach a size of about 55 mm. Males are somewhat smaller than females. The eyes are large and have a vertical pupil shape, and the parotid glands are small, the eardrums (tympanums) are clearly visible. The surface of the skin is warty, the most prominent reddish warts extending from the tympanum to the lumbar region, and other large glandular complexes are present on the armpits and ankles. Their coloration can vary from small black, brown dots to olive green spots. These glands produce toxic substances that are fatal to many animals.

The underside of the amphibian is off-white, and in the throat and chest area, it is often gray. This animal is found in eight European countries: Portugal, Spain, France, Belgium, the Netherlands, Luxembourg, Germany and Switzerland. There are also three European subspecies.

For their settlements, they chose not only all types of stagnant waters, but also long-lasting streams (mainly in Iberia), as well as rivers. Although this species prefers non-freezing reservoirs for breeding, since tadpoles are in the water during the winter, until metamorphosis. The nature of the terrain for terrestrial habitat is just as important to midwives as the breeding grounds. These can be slopes, embankments with a lot of small stones, sand or stone slabs, usually with a small amount of sparse vegetation. The microclimate in their dwellings and hiding places should be warm and humid.

Midwives reproduce sexually. Why do males at the beginning of the mating season, which usually begins in spring, call on females, making characteristic sounds at intervals of 1-3 seconds, more like “poo-poo-poo” and only female midwives, other types of amphibians respond to it do not react, since everyone has their own repertoire.

This “poo-poo-poo” is still tolerable, albeit a rather high sound, so some species with their vocal sacs can even produce unpleasant sounds, similar, for example, to the work of a drill, a drill or the bleating of a sheep. This signal serves as a stimulus for the females, and as soon as they are ready to lay their eggs, they rush to meet the call of the male. He, in turn, grabs the female by the waist and scratches her cloaca, stimulating the release of eggs, which he then waters with his seed.

Fertilized and linked in the form of a long string of eggs, the male winds them around his thighs and thus preserves them until the moment when the juveniles are ready to be born. For tadpoles, during this time, a caring father will have to pick up a reservoir where they will spend the winter, and only in the spring will metamorphosis occur and young midwife toads will appear.

The midwife toad is found from Central Europe to the Iberian Peninsula. This is a small animal about 50 mm long - on the upper side it is ash-gray with a yellowish, brownish or greenish tint; on the lower side it is whitish or yellowish-gray. The warts are partly dark, black or yellowish-white, their longitudinal row, running from the eye to the thigh, is whitish, sometimes bright red. Unlike toads, it has an eardrum. Close to it, the Iberian midwife toad (Alytes cisternasii) inhabits Spain and Portugal. The midwife toad lives exclusively in hilly and mountainous areas (up to 2400 m).

Video: Call of Alytes obstetricans

Prefers chalky soils, found in old quarries. But in general, habitats are very diverse, as well as water bodies in which tadpoles develop. Active at night. During the day, it hides in burrows, pits, burrows into the soil. It digs well and moves along vertical planes. The midwife toad, like frogs, collects food from plants, stones or catches it in the air, and not on the ground, like real toads. Feeds on various invertebrates. Winters in dry burrows and caves. Breeding in France lasts from March to August; in Germany, from early May to late July. The voice of the male midwife sounds pleasant, like a ringing glass bell. Spawns eggs in 3-4 portions, and one female lays only 120-150 eggs. The eggs are enclosed in two beaded cords, each of which reaches a length of 80-170 cm. The eggs lie at a distance of 4-7 cm from each other, and their number in one cord is from 18 to 54. The number of males in nature is greater than the number of females. The most amazing thing in the biology of the midwife toad is a special form of care for offspring. The mating male, with two middle fingers of the hind leg, grabs the end of the facial cord coming out of the female cloaca, and, gradually pulling it out, winds itself around its hips. Then he carries the eggs on himself until the time comes for the tadpoles to hatch. Unlike most other tailless amphibians, the laying of eggs and fertilization in the midwife occurs, as a rule, on land. Under artificial conditions at high temperatures (from 25 to 30°C), mating takes place in water, but in this case the male does not wrap eggs around his paws. During the laying period, males fight fiercely over females. Where there are many midwives, one male can mate and carry eggs from two or even three females. The male wanders with his burden everywhere, and it does not interfere with his normal life. Midwife eggs can withstand desiccation for a comparatively long time. This is due to the structural features of their membranes, the transparent mucous substance of which is permeated with fibers that form a number of layers. Each fiber bends, some branches. Neighboring layers of fibers intersect at a right angle, as a result of which the shell of the midwife egg is so hard that it feels leathery to the touch and reliably protects the developing embryo not only from drying out, but also from mechanical damage. However, they are not able to swell in water to the same extent as the homogeneous shells of eggs of other amphibians devoid of fibers. The development of eggs, depending on the weather, lasts from 3 to 7 weeks. By the time the tadpoles hatch, the male enters the water and begins to hurriedly swim in it. The larvae leave their facial shells within a few minutes, torn apart by the movements of their tail. Shaking off the cubs, the male removes the empty facial cords from his legs and, no longer caring about the larvae, again goes to land. The hatched larvae can live in a small amount of water. There are conflicting reports about the nature of their diet. The relatively small length of their intestines (only 4 times longer than in adults) indicates a carnivorous type of nutrition. However, there are indications that midwife tadpoles feed on plant foods. Some larvae believe that algae can support the life and growth of tadpoles, but they are not enough for metamorphosis. The transformation of larvae ends in late July - early October. However, the midwife is very characterized by a long development of tadpoles - for several years. This has been observed both in captivity and in natural conditions. In Switzerland, hatched - tadpoles have a length of 16-17 mm and already lack external gills, which in the embryo in the egg reach a very long length. Eight days later, "the larvae reach 32 mm in length, after about 4 months, i.e. in October, - 55, in March of the next year - 65, in May - 76 mm. In June, i.e. a year later, metamorphosis occurs. According to observations, in captivity, regardless of whether the larval development lasted two years or three, by mid-September the growth of tadpoles stops and resumes only in April, despite the fact that during this time the consumption of food by tadpoles did not decrease. than metamorphosed in the same summer.In the Pyrenees, in a lake at an altitude of 2400 m, the conditions for the existence of midwife tadpoles are very unfavorable - in connection with this, their hind limbs appear only after 13-14 months.Further development lasts several years, and some larvae are up to 20 years old.In artificial conditions, metamorphosis can be accelerated by increased lighting, high temperature, a small amount of water and shaking it, as well as sudden onset of hunger. When the midwife's caviar develops in the water, the transformation occurs in the same year. If the larvae hatched from eggs ripened on land are not allowed to enter and forced to live for several more weeks on land, then, having finally got into a reservoir, they develop extremely rapidly and quickly again get out onto land. An increase in the duration of the larval stage can be achieved by prematurely transferring the larvae into the water when they still have external gills, as well as by exposing them to darkness, low temperature, an abundance of still water, and sudden feeding after preliminary starvation. The long development of the midwife leads to the fact that the tadpole before metamorphosis is 174% of the length of adults. Sometimes males throw off clumps of eggs when frightened or when squeezing into a narrow gap between roots and stones. In the lost lumps of eggs, the larvae develop in the same way as in those that the male drags along with him. The larvae are able to live without water on damp ground for up to 4 weeks. Their skin becomes thicker, skin glands develop early, abundantly secreting mucus, and lungs quickly form. At the same time, the larvae crowd together, due to which moisture is better preserved.

Many of us dislike toads because they are repulsive and unpleasant to handle. And it is unlikely that anyone will dare to do this, except for lovers. And in vain. Representatives of this species have something to surprise a person. There are many unusual and interesting individuals among them. Among them is the midwife toad.

Appearance

Outwardly, she looks like her relatives. Although, of course, it has individual characteristics that make it possible to distinguish it from other toads. Like all members of this family, her skin is dry and warty. Its color is ash gray with olive spots. The midwife toad has a small head with large eyes, with closing eyelids. In length, these animals reach 5.5 centimeters. These animals have eardrums and hear well. They also distinguish colors and smells. The warts on the toad's body are located for a reason. These are glands that secrete poisonous mucus at the moment of danger. If someone tries to eat it, they will certainly get poisoned. Sometimes such daredevils from the animal world even die.

Where does he live and what does he eat

Its habitat is dry land. Prefers mountainous terrain, which allows this creature to hide under rocks during daylight hours. Also, this amphibian can burrow into the soil or hide in a mink or hole. These toads also settle near rivers and lakes with clean water. You can meet them in the forest. Usually they are found in Western Europe, Germany, France, Luxembourg, the Netherlands, Great Britain, Belgium, Switzerland. These amphibians feed on worms, slugs, flies, caterpillars, spiders, wood lice. They hunt them at night, sitting motionless and waiting for their prey. From October to March, this amphibian hibernates.

Toads are different

There are several types of these amphibians. For example, the Iberian midwife toad lives in central Spain, southern and eastern Portugal. It has a brownish back with dark spots and a dirty white belly. Knows how and loves to dig holes. The provincial midwife toad has a whitish or grayish color with dark spots. Prefers to live in ponds, ponds, swamps, pastures, forests. It is considered a rare species and is protected in regional territories.

You rarely see the Balearic midwife toad. Scientists have proven that its habitat is gradually shrinking. Currently, this species lives in the mountainous part of about. Mallorca, where it is always dry and hot. This small, only 3.5-3.8 centimeters long amphibian has smooth skin, a dark green or golden yellow color, and a black triangle on the back of the head. Its body is flattened, thanks to which the Balearic toad penetrates into narrow cracks between stones in the caves where it lives. It differs from other midwives in that reproduction takes place not on land, but in puddles left after rain.

Why is she called that

The reproduction of the midwife toad deserves special attention. After all, it is precisely the way in which it occurs that it owes its name. To mate with the female, the male makes melodious sounds while sitting in his mink. This gentle singing attracts the lady and she comes close to the house in which the gentleman is waiting for her. Without wasting time, the male climbs onto the back of the female, clasps her body with his front paws, and inserts his hind legs between her hind limbs. In this position, it is convenient for him to immediately fertilize the eggs after the female lays them. Usually her clutch consists of two ribbons containing 20-60 eggs. After mating, the male wraps these cords around his thighs with the help of his hind legs. He does not stop there, but continues to search. Mating takes place on land. Having fertilized in this way, 2-3 more females, he continues to lead a normal life.

Caring for offspring

The male takes care that nothing bad happens to the caviar. He wears it on himself, periodically moistening in a pond. If frightened, it may shed its spawn or lose it while moving. But nature itself made sure that the masonry was safe for the entire period of incubation. covered with a dense shell that protects them from drying out. Even in lost eggs, development continues. After 3-4 weeks, the midwife toad, the photo of which is presented in this article, goes to the reservoir. There, she swims actively so that all the tadpoles hatch, and then removes the ribbons from her body and returns to land. Since the reproduction of these amphibians does not depend on any season, and mating can occur in any of them, it may be that the larvae do not have time to turn into an adult before spring. Then they burrow into the silt and hibernate at the bottom of the reservoir. Interestingly, the midwife toad can spend quite a long time at the tadpole stage until favorable conditions for transformation occur, for example, an increase in water temperature.

This is how this amphibian spends its life. The midwife toad looks very unusual with caviar on its paws. Interesting facts collected at different times suggest that these creatures came to England due to the fact that they were accidentally brought there along with plants. In the Pyrenees, they live at an altitude of 1.5-2 thousand meters. They are distinguished from other amphibians by a thick round tongue. So do not disdain midwife toads. They are very interesting animals and know how to take care of their offspring like no other.

midwife toad (Alytes obstetricans)

It is found from Central Europe to the Iberian Peninsula. This is a small animal about 50 mm long; on the upper side it is ash-gray with a yellowish, brownish or greenish tinge; on the underside - whitish or yellowish-gray. The warts are partly dark, black or yellowish-white; their longitudinal row, running from the eye to the thigh, is whitish, sometimes bright red. Unlike toads, it has a tympanic membrane. The closely related Iberian midwife toad (Alytes cisternasii) inhabits Spain and Portugal.

The midwife toad lives exclusively in hilly and mountainous areas (up to 2400 m). Prefers chalky soils, found in old quarries. But in general, habitats are very diverse, as are the reservoirs in which tadpoles develop. Active at night. During the day it hides in burrows, pits, burrows into the soil. Well digs moves along vertical planes.

The midwife toad, like frogs, collects food from plants, stones, or catches it in the air, and not on the ground, like real toads. Feeds on various invertebrates. Winters on land in burrows and caves.

Breeding in France continues from March to August; in Germany - from the beginning of May to the end of July. The voice of the male midwife sounds pleasant, like a sonorous glass bell. Spawns eggs in 3-4 portions, and one female lays only 120-150 eggs. The eggs are enclosed in two beaded cords, each of which reaches a length of 80-170 cm. The eggs lie at a distance of 4-7 cm from each other, and their number in one cord is from 18 to 54. The number of males in nature is greater than the number of females.

The most amazing thing in the biology of the midwife toad is a special form of care for offspring. The mating male, with two middle toes of the hind leg, grabs the end of the facial cord emerging from the female's cloaca, and, gradually pulling it out, wraps it around his hips. Then he carries the eggs on himself until the time comes for the tadpoles to hatch. Unlike most other tailless amphibians, the laying of eggs and fertilization in the midwife occurs, as a rule, on land. Under artificial conditions at high temperatures (from 25 to 30°C), mating takes place in water, but in this case the male does not wrap eggs around his paws.

During oviposition, males fight fiercely over females. Where there are many midwives, one male may mate and carry eggs from two or even three females. The male wanders with his burden everywhere, and it does not interfere with his normal life. Midwife eggs can withstand desiccation for a relatively long time. This is due to the structural features of their membranes, the transparent mucous substance of which is permeated with fibers that form a number of layers. Each fiber bends, some branches. Neighboring layers of fibers intersect at right angles, as a result of which the midwife egg shells are so hard that they feel leathery to the touch and reliably protect the developing embryo not only from drying out, but also from mechanical damage. However, they are not able to swell in water to the same extent as the homogeneous shells of eggs of other amphibians devoid of fibers.

The development of caviar, depending on the weather, lasts from 3 to 7 weeks. By the time the tadpoles hatch, the male goes to the reservoir and begins to swim in it hastily. Within a few minutes, the larvae leave their facial shells, which have been torn apart by the movements of their tail. Shaking off the cubs, the male removes the empty facial cords from his legs and, no longer caring about the larvae, again goes to land.

The hatched larvae can live in a small amount of water. There are conflicting reports about the nature of their diet. The relatively small length of their intestines (only 4 times longer than in adults) indicates a carnivorous type of nutrition. However, there are indications that midwife tadpoles feed on plant foods. Some larvae believe that algae can support the life and growth of tadpoles, but they are not enough for metamorphosis.

The transformation of larvae ends in late July - early October. However, the midwife is very characterized by a long development of tadpoles - for several years. This has been observed both in captivity and in natural conditions. In Switzerland, hatched - tadpoles have a length of 16-17 mm and already lack external gills, which in the embryo in the egg reach a very large length. Eight days later, "the larvae reach 32 mm in length, after about 4 months, i.e. in October, - 55, in March of the next year - 65, in May - 76 mm. In June, i.e., a year later, metamorphosis occurs According to observations, in captivity, regardless of whether the larval development lasted two years or three, by mid-September, the growth of tadpoles stops and resumes only in April, despite the fact that during this time the food intake of tadpoles did not decrease. in young midwives noticeably larger in size than those metamorphosed in the same summer.In the Pyrenees in the lake at an altitude of 2400 m, the conditions for existence of tadpoles of Midwives are very unfavorable; in connection with this, their hind limbs appear only after 13-14 months.Further development lasts several years, and some larvae are up to 20 years old.

Under artificial conditions, metamorphosis can be accelerated by increased lighting, high temperature, a small amount of water and shaking it, as well as a sudden onset of hunger.

When the midwife's caviar develops in water, the transformation occurs in the same year. If the larvae hatched from eggs ripened on land are not allowed into the water and forced to live for several more weeks on land, then, having finally got into the reservoir, they develop extremely rapidly and quickly again get out onto land. An increase in the duration of the larval stage can be achieved by prematurely transferring the larvae into the water when they still have external gills, as well as exposing them to darkness, low temperature, an abundance of calm water, and sudden feeding after a preliminary starvation. The long development of the midwife leads to the fact that the tadpole before metamorphosis is 174% of the length of adults.

Sometimes males throw off clumps of eggs when frightened or when squeezing into a narrow gap between roots and stones. In the lost lumps of eggs, the larvae develop in the same way as in those that the male drags along with him. The larvae are able to live without water on damp ground for up to 4 weeks. Their skin becomes thicker, skin glands develop early, abundantly secreting mucus, and lungs quickly form. At the same time, the larvae crowd together, due to which moisture is better retained.

It owes its name to the unusual behavior of the male, which, after mating, wraps mucous cords with eggs around the thighs and wears it until the larvae appear.

Basic data:
DIMENSIONS
Length: adult frog 4-5 cm.
Weight: 9-10 g.

BREEDING
Puberty: usually from 12-18 months.
Mating period: from March.
Number of eggs: up to 54 in each string.
Metamorphosis: The development of the egg and tadpole, which turns into an adult, lasts about 8 months.

LIFESTYLE
Habits: kept alone or in groups; in Central Europe spends the winter in hibernation.
Food: small insects.
Life span: more than 5 years.

Related species
The round-lingual family includes 10 species. Most frogs belong to the true frog family, but the midwife toad is not related.

In Western Europe, North Africa and Mallorca, there are four types of midwife frogs. These shy nocturnal amphibians are hard to see, but their presence is betrayed by ringing voices reminiscent of the sound of bells.
reproduction
The midwife frog has such a feature that the male takes care of the eggs, who carries the eggs on himself until the tadpoles hatch from them. On warm May nights, males sing loudly, attracting females. During the laying period, they fight fiercely for females. Female frogs - midwives throw out cords with caviar, which males fertilize. The males then wrap the cords around their hind legs. Males carry their eggs for several weeks. Sometimes the female lays eggs several times. It also happens that a male fertilizes the eggs of two or three females and carries all the eggs on himself. The eggs develop into embryos that feed on the yolk reserves. The male must keep the egg shells moist. Shortly before the appearance of the tadpoles, the male midwife toad, following instinct, enters the pond and immerses the back of the body in the water. At this time, the tadpoles emerge from the eggs. Tailed tadpoles breathe with gills. The development of tadpoles ends in late July - early October, but sometimes it can also continue for several years. Then the tadpole hibernates, becoming a frog in spring.
Place of residence midwife frogs
The midwife lives exclusively in hilly and mountainous areas. She prefers chalky soils, appears in old quarries.
Midwife toads during the day sit in shelters under stones, tree trunks or in rodent burrows. Under the cover of darkness, they leave their hiding places and go hunting. Midwife toads willingly settle in places with dry sandy soil. On damp evenings, midwives may hunt far from their hiding places. Frogs spend the cold season in pits and holes of rodents.
Food
All small insects that it can swallow are suitable as food for the midwife toad: beetles, crickets, bedbugs, caterpillars, flies, and centipedes. The midwife frog leaves its hiding place at night and goes hunting. The midwife toad holds small prey with the tip of a sticky tongue. Tadpoles feed on plant foods, gnawing algae with small horny teeth. However, they are also known to take animal food. Frogs gradually switch to animal food, like adults, they feed on insects.
self defense
The back of the midwife toad is covered with small warts, from which, when the frog is in a state of irritation or if it is attacked by an enemy, a poisonous liquid with a strong odor is released. This means of self-defense is so effective that it makes any predator stop attacking. Thanks to this feature, the midwife frog has practically no biological enemies: its poison scares off not only land-based predators, but also fish. In tadpoles, unlike adults, venom glands are not developed.

Adaptation abilities
The midwife frog lives in a harsh arid climate. It inhabits deep caves in the north of Mallorca. Due to the flattened body, the midwife frog easily penetrates through the narrow cracks between the stones. The only source of water in the region is rain puddles in the depressions of the rocks - only in them midwife toads can breed. The midwife frog is threatened with extinction because it lives in a small area in the hottest and driest part of Mallorca.

Good thing you...

In some areas of France, midwife toads live in the dunes along the sea along with the jungle toad.
The body of a midwife toad contains so much poison that the snake that ate it dies after a few hours.
Unlike the long thin tongues of most amphibians, the thick tongue of the midwife toad is not ejected from the mouth.
The common midwife toad was twice accidentally brought into England along with a cargo of plants. Today, midwives live in the counties of Bedfordshire and Yorkshire.
Midwives are found in the snows of the Pyrenees at an altitude of 1,500-2,000 m above sea level.
Places of residence
midwife frog lives in Central Europe and the eastern part of the Iberian Peninsula.
Preservation
The danger for the midwife toad is pollution and drainage of water bodies - its breeding grounds. In some areas, midwife frogs are bred in captivity and then released in places suitable for habitation.