What is spadefoot? Common spadefoot - Pelobates fuscus
The spadefoot spadefoot is a representative of tailless amphibians. These frogs live in Central Europe, on South Western Siberia, in Crimea, the North Caucasus, Kazan and Leningrad.
They only reproduce in water bodies and spend the rest of their lives on land.
Spadefoots are excellent at digging, so during the day they burrow into the ground and in the evening they crawl out of their hiding places. Due to the fact that these frogs need to dig the ground, they do not live everywhere; rocky soils are not suitable for them; their habitat requires flat terrain with fairly loose sandy or clay soil.
A sandbox can completely bury itself in soft soil in 2-3 minutes. The frog digs the ground with its hind legs and plunges into the hole with its backside, vertically.
Because these frogs spend a lot of time underground, their lungs are not very well formed. They hunt at night, and the more wet air, the more active the spadefoots are. If the humidity is about 89% and the temperature stays within 10-15 degrees, then 11% of spade moths are active; if the humidity reaches 90-95% and the temperature remains the same, then this figure increases to 52%.
These frogs eat great amount invertebrates. But basically, spadefoots prefer ants, spiders and ground beetles; these insects make up about 87% of the total diet. Spadefoot frogs differ from other frogs in that they practically do not feed in water bodies, since 99% of the diet consists of terrestrial food. When examining the stomachs of these frogs, no flying insects were found.
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Among other amphibians, this species is the first to go into hibernation. The duration of hibernation is about 200 days. Spadefoot spadefish spend the winter on land, burrowing into the ground; they can also overwinter in rodent burrows and nests of shore swallows. Spadefoot spadefoots emerge from hibernation near Kiev in March, and in more northern regions a little later - in April or May.
Listen to the voice of the common spadefoot
Female spadefoot spade eggs lay in early spring, after they emerge from hibernation. They do not spend much time in reservoirs. The entire population lays eggs over a period of approximately 25 days. Male spadefoot spadefoots do not have “nuptial calluses,” as do male spadefoots. They call females by making a gurgling sound underwater.
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The clutch of these frogs looks like thick cords consisting of outer shells, inside of which the eggs are randomly located. The eggs are laid underwater. These cords are attached to various underwater objects. The clutch of one female consists of 1200-2300 eggs, the diameter of which reaches 1.5-2.5 millimeters.
The tadpoles of these frogs take longer to develop than other species of amphibians; this process takes 90-110 days, and sometimes it takes even longer. The external gills of tadpoles disappear on the 7th day, and limbs begin to form on the 34th day. On the 67th day hind legs joints appear. On the 92nd day, the front legs are formed, and on the 94th the tail disappears.
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But spadefoot tadpoles grow faster than other amphibians. Their growth per day is about 1.2 millimeters. Before metamorphosis occurs, the tadpoles become so huge that their body length is 40% greater than the size of a mature female and amounts to 73-175 millimeters.
At first, tadpoles live at the bottom; during this period they are hardly noticeable. In the second half of life, tadpoles rise into the water column. Their diet consists of plant foods, so they have very long intestines. The length of the intestine is almost 6 times greater than the entire body. They feed on plant foods, therefore they have a deep oral cavity, along the edges of which there is a large fringe, they also have a powerful horny beak and many teeth. These features significantly distinguish spadefoot tadpoles from other amphibians. In the oral funnel, spadefoot tadpoles have 1100 teeth, which is 2 times more than in a tadpole
Candidate for pet of the frogs is the common spadefoot ( Pelobates fuscus) - a representative of a separate family of spadefoots. This is a small amphibian up to 8 cm long, usually yellow-brown or light gray with brown and black spots and red dots. The common spadefoot got its name due to the fact that the skin sometimes begins to smell like garlic. The common spadefoot is found in areas with soft soil, as they like to burrow in the ground. Therefore, they can often be found in the fields, but only at night and mainly in wet weather or before its onset. The spadefoot burrows into the ground with the help of its hind legs, armed with a spade-shaped tubercle.
The spadefoot moves into water bodies only for the spawning period, that is, for 20-25 days. The female lays 1200-1800 eggs. Among all amphibians, the spadefoot has the longest hibernation - up to 200 days. Development lasts longer than in other amphibians - 90-110 days. Therefore, spadefoots can appear interesting object to study the process of reproduction and development of amphibians.
Maintenance and care of common spadefoot
Young spadefoot tadpoles feeding plant food, adult spadefoots eat ants, ground beetles, spiders and insect larvae, which makes up 80% of their food. The spadefoot also takes great pleasure in eating earthworms, slugs and other invertebrates. It is recommended to maintain the same diet if you decide to keep the common spadefoot as a pet.
To keep the common spadefoot at home, a 30-liter terrarium with a mandatory separate reservoir is recommended, the water in which should preferably be changed daily. It is recommended to lay a 5-8 cm layer of earth, peat, tree bark at the bottom, and you can add a little sand. The presence of green plants is a must. For adult individuals, additional heating of the terrarium is not required; 15-20 °C with air humidity from 75 to 90% is sufficient. Because the spadefoot leads night look life, then the terrarium does not need to be equipped with lighting.
You can buy common spadefoot in pet stores or large poultry markets.
Extraordinary chapel
The entire territory of Belarus
Garlic family ( Pelobatidae).
It's quite normal look, is distributed rather unevenly throughout the entire territory, including Poozerie.
Medium-sized amphibian. Body length is 4-6 cm, but in the population individuals of this size make up only 8-12% total number(most measure 3-4 cm). Weight 5.8-20.0 g. Body shape oval, slightly flat. The muzzle is rounded, the forehead is convex. The limbs are relatively short. The body shape resembles a toad. The skin is smooth or slightly bumpy. There is no eardrum. The eyes are big. Distinctive feature is a vertically set slit pupil and a very large spade-shaped hard yellowish calcaneal tubercle on inner surface hind legs, a horny plate, with the help of which it is quickly buried. Males have an oval gland on their shoulders, they are slightly smaller than females and are colored more contrastingly. There are no nuptial calluses. Numerous skin glands secrete a poisonous secretion that smells like garlic (hence the name).
The color is dim. The upperparts are light gray, sometimes dark gray, with a yellowish or brown tint. Against this background, dark olive, dark brown or black spots with red dots are visible various shapes and magnitude. The underparts are light (grayish-white) with a slight yellowness, with dark spots, sometimes without them.
The larvae (tadpoles) of spadefoot moths are very large: the length including the tail reaches7.3-17.5 cm, although in newly hatched ones it does not exceed 3-5 mm. After reaching the 26th stage of development, the larvae of spadefoot moths acquire a peculiar shiny bluish tint. The body is quite massive, the tail is pointed at the end. The rows of denticles on the oral disc are usually paired, which are interrupted in the middle, at upper lip- 3, on the bottom - 4-5 rows.
Common spadefoot- typical terrestrial view. Spadefoots come to water bodies only during the breeding season, spending the rest of the time on land. Due to its burrowing lifestyle (usually buried in the soil during the daytime), it adheres to lighter and looser soils. Most often, spadefoot can be found in floodplains of rivers and lakes, especially in areas of meadows bordering sandy soils, as well as in mixed and deciduous forests and other places. It gravitates noticeably towards places transformed by man (fields, gardens, vegetable gardens, forest belts, parks), where the soil is loosest. The average population density is 10-20 individuals/ha, but in some areas the number of spadefoot spadefoots can be relatively high - up to 100-800 individuals per 1 hectare. The ratio of males to females in Belarus is 1:1.38.
You can most often meet spadefoot spadefoots at dusk, at night and morning time and only occasionally during the day (in cool or rainy weather), since at this time they are still in shelters. This is probably why the spadefoot spadefoot is considered a rare species or is not known at all. For a day it buries itself in the soil, and buries itself quickly (within a few minutes), raking the soil to the sides with its hind limbs, which is facilitated by powerful calcaneal mounds. When burrowing, it sinks into the ground with the back of its body. On slightly damp sand, the spadefoot has time to bury its head in 2-3 minutes. It usually buries itself in the soil during the daytime, although it often uses rodent holes, piles of stones, logs, etc. for shelter.
At dusk you can find quite a lot of these small amphibian diggers. On high sandy shore On the Dnieper River, which borders the lowland, on a July night there were up to 4-5 individuals per 1 m².
The food composition of the spadefoot spadefoot, which leads a twilight and nocturnal lifestyle, contains practically no flying or water forms. The most common food of the spadefoot is terrestrial invertebrates - dipterans (34.5%), beetles (11.4%), caterpillars (13.1%), spiders, earthworms.
Garlics, like toads, are not always protected from enemies by poisonous skin secretions. Its venom can cause fatal poisoning only in small individuals. It is safe for humans in doses that are lethal to insects and lizards. Garlic can be safely picked up. She often becomes a victim of other animals - an ordinary snake, common viper, curlew, stork, heron, bittern, falcon, black grouse, black kite, buzzard, eagle owl, little owl, tawny owl, rollers, crows, magpies, as well as hedgehogs, foxes, ferrets, minks, martens, badgers and otters.
He spends the winter on land, burrowing into the soil to a depth of at least 30-50 cm ( sometimes up to 1.5 m) or uses other shelters (rodent holes, basements, cellars). Goes to wintering relatively early - during September. In spring it appears no earlier than April.
For breeding (late April - early May), spadefoots usually choose bodies of water with a more or less constant water level and depths from 0.5-0.7 m to 1.0-1.3 m , although occasionally spawning occurs in temporary bodies of water. Mating cries males are relatively quiet, as they are only fed underwater. From the shore they resemble a gurgling sound “knock, knock, knock” or"krok, krok, krok". On land, sometimes spadefoot moths make peculiar abrupt (grunting) sounds.
Although males do not have nuptial calluses, they firmly hold the females by the lumbar region during mating. Sometimes spadefoot mating occurs on land, on the way to a body of water. However, most often, unlike most other tailless amphibians, individuals of spadefoots mate in the water column, where spawning occurs. They do not form clusters during reproduction. As a rule, there are no more than 15-20 pairs in one body of water.
Spawning also occurs in depth, at a water temperature of 12-20°C, sometimes a little lower. The clutch is in the form of two mucous, relatively thick sausage-shaped cords 40-80 cm long, inside of which eggs are randomly scattered. The cords are wrapped around seaweed, sunken branches and other underwater objects. The fertility of females ranges from 1200 to 3200 (usually 1600-1700) eggs. Spawning of the spadefoot spadefoot is perhaps the least noticeable in nature.
The larval period lasts relatively long - 100-110 days. At the beginning of development, spadefoot tadpoles are little noticeable in water bodies, but after 30-40 days (until June), when they reach 35-50 mm or more (sometimes up to 70-100 mm), and later they are very noticeable. If you scare a flock of tadpoles that are basking in the upper layers of water, you can even notice how they move large vegetation under the water. Giant tadpoles that barely fit in the palm of your hand. D line with tail reaches 10 cm or more at the end larval stage 7.0-16.0 cm. The larvae feed on algae. They scrape them off the surface aquatic plants, stones and other objects. Spadefoot tadpoles are the most herbivorous; plant foods make up up to 80% of their diet. This is facilitated by a well-developed oral apparatus: powerful beak and relatively a large number of denticles on the oral disc (more than 1000).
Olga Vasilevskaya, approx. Pinsk
, (they can be downloaded from Google Play or uploaded to the AppStore),
colored laminated identification tables: , .
Common spadefoot - Pelobates fuscus(Laurenti, 1768)
(= Rana vespertina Pallas, 1771)
Appearance. Small amphibians; maximum body length 71 mm (in Europe up to 90 mm). Forehead convex between the eyes. Inner heel tubercle yellowish or light brown. Leather on the back and sides it is smooth, but there are small flat tubercles scattered throughout the body. Well developed between the toes of the hind limbs swimming membrane. Above painted in gray or brown tones with a more or less symmetrical pattern of dark spots, sometimes forming stripes; the edges of the spots are clearly defined. A light stripe runs along the back. In addition, small reddish spots may occur mainly on the sides. The underparts are light, often with dark gray spots. Albinos (adults and larvae) are occasionally found.
Spreading. The species' range covers the central and eastern regions of Europe from eastern France, Belgium and Holland in the west to Western Siberia (Trans-Urals) and Kazakhstan in the east. The northern border in Europe runs through Denmark, the very south of Sweden, Poland, the southern border through the north of Italy, Yugoslavia, and Bulgaria. In the territory former USSR the species is distributed from the outskirts of St. Petersburg through Vologda, Vyatka region, Udmurtia and Perm region to the Tyumen region in the north and to the coast of the Black Sea, Crimea and the North Caucasus (to the south Krasnodar region, Chechnya and Dagestan) in the south. Absent in the lower reaches of the Volga, but lives on the Ural River up to the mouth. In the north-west of Kazakhstan it is found in the basins of the Ural, Emba, Irgiz and Turgai rivers. Central Asian finds of spadefoot larvae in Kazakhstan (Aral Sea), Uzbekistan (outskirts of Tashkent) and Kyrgyzstan (Chui Valley), geographically very remote from the species’ range, upon re-examination turned out to be giant tadpoles of the lake frog.
Taxonomy of the species. The species consists of 2 subspecies. Most of the range, including the territory of the former USSR, is occupied by the nominative subspecies, Pelobates fuscus fuscus(Laurenti, 1768). In northern Italy (Po Valley), another subspecies lives isolated, Pelobates fuscus insubricus Cornalia, 1873.
Habitat. Inhabits plains in forest, forest-steppe and steppe zones, preferring areas with loose soil. It rises up to 810 m above sea level (Czech Republic); in the Carpathian region up to 360 m. Although the spadefoot is primarily a resident of open landscapes, it can be found in quite a variety of habitats - in broad-leaved, mixed, coniferous (pine) forests, bush thickets, in floodplains of rivers and lakes, in meadows, in swamps, steppes, gardens, parks, fields, vegetable gardens, along roadsides, etc. In the south of their range, in areas with arid climates, spadefoots are associated with river valleys, which is why their distribution here is tapered. The presence of reservoirs and soft, loose soil determine the habitat of the species. The most striking feature of the spadefoot spade is its ability to quickly burrow into the soil using the hind limbs and large calcaneal tubercle as a shovel. Therefore, it is not surprising that it prefers light sandy soils, settles in cultivated fields, where its numbers can increase several times, but avoids rocky soil.
Activity. The common spadefoot spadefoot is a very dry-loving species. Found in water bodies only during the breeding season. During the day it leads a very secretive lifestyle, usually buried in the soil, sometimes to a depth of 1 m. It also uses rodent holes, moles, leaf litter, stones, fallen logs, etc. for shelter. During the breeding season, animals are active almost around the clock; outside it only at dusk and at night, and only occasionally can they be observed before sunset. IN cloudy weather spadefoots can be found in daylight hours days.
Reproduction. In the spring after wintering appears in mid-March - early May at air temperature 12-14°C and water temperature 8-10°C. It breeds, as a rule, in non-drying stagnant bodies of water - ponds, sand quarries, ditches, holes with fairly clear water and semi-aquatic vegetation, although eggs can also be found in temporary bodies of water (shallow puddles, ruts on the road, etc.).
Pairing usually occurs under water soon after the individuals arrive at the reservoir at a water temperature of 9-15°C. The spawning period covers the second half of March - early June. Laying eggs resembles a thick (1.5-2.0 cm) sausage-shaped cord with a length of 40 cm to 1 m, usually about 30-50 cm, which contains from 400 to 3200 eggs with a diameter of 1.5-2.5 mm. These cords are usually placed on plants near the surface of the water:
Hatching of larvae from caviar occurs in 5-11, usually 8 days. The hatched tadpoles are very small, only about 4-5 mm in length. They grow very quickly and before metamorphosis reach large sizes, sometimes up to 175 mm in total length (in Europe up to 220 mm). At first, tadpoles live in the bottom layer of the reservoir, but then they appear in the water column and near the surface. Larval development can last from 56 to 140 days. Many tadpoles dies when water bodies dry up, as well as in winter, if they do not have time to undergo metamorphosis, although there are known cases of successful wintering at the larval stage. The overall survival rate to the fingerling stage can be only up to \% of the laid eggs. The emergence of fingerlings from reservoirs begins in early July and can continue until the second half of September. After metamorphosis, the fingerlings are only 10-33 mm long and weigh up to 6 g. They live in the grass or on damp soil near a pond. They often spend the winter here, buried in the ground.
Sexual maturity occurs in the third year of life with a minimum length of about 41 mm for males and 43 mm for females. The sex ratio is approximately equal. In nature they live for at least 4 years.
Nutrition. They feed mainly on various terrestrial insects: beetles, especially ground beetles and click beetles, butterfly caterpillars, etc., as well as spiders, centipedes, and earthworms. Tadpoles feed on detritus in the first two months of their development, and then switch mainly to plant foods, which can account for up to 79%. They scrape algae from the surface of aquatic plants, stones or other objects, but can also swallow whole leaves of duckweed floating on the surface of a reservoir. Animal food (protozoa, rotifers, crustaceans and small mollusks) appears to be an obligatory component of the diet, although insignificant in volume.
Wintering. Spadefoots go to winter in September-October. They overwinter on land, burrowing into the ground or using rodent burrows, often also in wells and cellars.
Abundance and conservation status. The common spadefoot is not one of the rare species, and in some places it reaches high numbers. Found in many nature reserves. As a rare species on the border of its range, it is listed in the Red Book of Estonia, but is not included in the Red Books of the USSR and other republics. Protected by the Berne Convention (Annex II). There is no threat to the existence of the species. The ecology of the species has not been sufficiently studied.
Similar species. It differs from the closely related Syrian spadefoot in the shape of its forehead (“bump”) and more strongly developed membranes on the hind limbs. Although the ranges of both species in the territory of the former USSR are geographically isolated, they are located close to each other in the Danube Delta region and in Dagestan.
In our article we want to talk about your possible pet. Meet the common spadefoot. IN Lately Completely exotic pets came into fashion, pushing traditional cats and dogs into the background.
Who is this spadefoot?
The common spadefoot spadefoot (pelobates fuscus) is a frog that is a representative of the whole spadefoot spadefoot family. By the way, this is a small amphibian creature, up to eight centimeters long. Typically the frog is light gray or yellow-brown in color.
Here's yours interesting name I got the common spadefoot because its skin sometimes gives off a garlicky odor. The glands of the amphibian secrete mucus with such unpleasant smell in case of danger.
Common spadefoot: description
If you look at the spadefoot, it looks like the most common toad, but her skin is completely smooth. The frog has a stocky body, but hind legs quite short. Her eyes are large and bulging, and she has teeth. A light stripe runs along the back.
Common spadefoot: habitat
Garlic is unusual creature. It is found in places where there is soft soil. This is due to the fact that she loves to rummage in the ground. That is why such frogs are often found in fields, but only in damp conditions and at night. They burrow into the soil with the help of their hind legs, which are armed with a spade-shaped tubercle. The frog spends most of its time underground at a depth of fifteen centimeters. Moreover, spadefoots dig the ground with amazing speed and quickly go vertically down. During the daytime, they sit in burrows, and at night they come out in search of food, but they can hunt only when the air is sufficiently humid; if it is dry, then they will not even leave their shelter, no matter how hungry they are. Adults winter from September to April in the burrows of rodents, swallows, moles, and in holes under stumps.
The common spadefoot spade lives in deciduous and mixed forests, meadows, vegetable gardens, swamps and lakes.
The frog can be found only at dusk, at night or in the morning, and even then, only when the air humidity is sufficient for it. It is for this reason that the spadefoot spadefoot is considered a fairly rare species.
Reproduction of spadefoot
The frog lives in reservoirs only during reproduction, which is approximately twenty-five days. The spawning process itself occurs in water. The female is capable of laying up to 1800 eggs. It should be noted that among all representatives of amphibians, the spadefoot has perhaps the longest period of hibernation, which is two hundred days.
All mating season A frog spends time near a pond. The more raw and rainy summer, the longer the breeding season will last. Females lay their string-like clutches directly on plants in ponds.
The tadpoles then develop for about one hundred days. Very small tadpoles are orange in color, later they become golden and brownish. To feed themselves, they take a vertical position and collect the necessary food from the water surface with their mouths. Their diet is plant food. They prefer not to swim in shallow water. Tadpoles have enough large sizes, they barely fit in the palm of your hand.
As soon as their forelimbs appear, they instantly leave the pond and go to land, burrow underground and wait for the moment when their tail falls off. The process of tadpole development itself can last from three to five months. Puberty amphibians occurs at the age of three years.
Amphibian nutrition
The common spadefoot is only nocturnal and at the same time feels great on land. IN summer time she can make entire journeys, moving six hundred meters away from the water. Amphibians rest during the day and come out to hunt at night. They subsist on insects, worms, and snails.
After feeding at night, the common spadefoot (photos are given in the article) digs a hole for itself with its hind legs and plunges its back into the ground, while closing its eyes and nostrils. It only takes a few minutes for her to bury herself completely.
Frog self-defense
The frog uses garlic odor to protect itself from enemies. It stands out at the slightest danger and is able to discourage the desire to attack. If the spadefoot was unable to escape in time, it begins to croak loudly, swells up and stands on its legs. In this simple way, she tries to increase her size and thereby frighten the enemy. Both females and males can croak, but they do not have resonators, and therefore can only be heard near water. IN wildlife the amphibian lives five to six years. And at home, with normal care, these frogs can live up to eleven years.
The venom from the frog's skin glands is not dangerous and can only harm a small number of frogs. It does not pose a danger to humans, and therefore the frog can be safely picked up. Often, the spadefoot spadefoot itself becomes food for snakes, vipers, herons, storks, curlews, falcons, bitterns, black kites, black grouse, owls, eagle owls, owls, badgers, crows, hedgehogs, ferrets, foxes, and minks. As you can see, this one has enemies little creature more than enough.
Garlic at home
In principle, the common spadefoot can also serve as a pet. It must be kept in captivity in a special terrarium of at least thirty liters. There must certainly be a reservoir in it, the water in which should be changed daily. At the bottom of the tank you need to pour a layer of soil five to eight centimeters thick, consisting of peat, tree bark and sand. There must also be green plants in the terrarium.
For adult individuals, you do not need to additionally warm the air, twenty degrees will be enough, but you should maintain air humidity, it should be at least 75 percent, and better if its value is close to 90%. The spadefoot is a nocturnal creature, and therefore there is no need to provide lighting in the terrarium.
Young frog tadpoles should be fed plant food. Adults need ants, ground beetles, spiders, insect larvae, all of which make up more than eighty percent of their food. Garlic moths also love to eat earthworms and slugs. You need to purchase a frog at pet stores.
Difficulties of keeping an amphibian
If you decide to keep a frog at home, then you need to immediately evaluate all the difficulties associated with this. Is common spadefoot really that easy to care for? Systematic control of humidity, and for young individuals also temperature, should become an indispensable condition for keeping a frog.
In addition, you should remember that the terrarium needs to be cleaned very often and the water changed daily. It’s also not easy to get live food, and it’s inconvenient to breed it at home, and it’s not practical, since it can spread throughout the entire apartment. Frogs are capable of escaping from the terrarium and simply dying in the apartment from dehydration, and therefore it must be kept closed. Remember that the spadefoot spadefoot is a nocturnal creature, so you can hardly hope that you will be able to watch it during the daytime. This is not a pet that will entertain you; rather, it will require close attention and proper care from you.
More likely, most The frog will spend time buried in sand or substrate, and will only come out to feed. For supporting normal humidity The inside of the terrarium needs to be sprayed with water. And for an amphibian shelter, you can put pieces of tree bark inside.
Rare view
It should be noted that the habitat of the spadefoot spadefoot is quite wide. She lives in Central and Eastern Europe, Western Asia. And yet, the amphibian is one of the rare species. For example, it is listed in the Red Book of Estonia, as well as the Red Book of the Moscow, Oryol and Lipetsk regions. There is currently no threat of its extinction. Rather, it is protected as a rare, little-studied amphibian. This is it unusual creature- common spadefoot. The Red Book of the Moscow Region in the second edition already included the frog in its lists due to the fact that, compared to the last century, there were fewer places where it lives, and the number of individuals also suffered. It is believed that this is due to the long period of development of her offspring, as well as significant pollution environment, which also significantly affects spadefoot.
It should be noted that many reptiles and amphibians are included in the Red Book of the Moscow Region, this is explained by the fact that these animals suffer the most from anthropogenic influence of people. Amphibians are very attached to their habitat, unlike other animals, they cannot migrate over long distances, moreover, they are connected directly to their body of water. Currently, a decline in the number of amphibian creatures is observed throughout the world. Why this happens is unknown, no explanation has been found for this phenomenon.