How red-eared turtles lay their eggs
In their natural habitat, pregnant female red-eared turtles go ashore to lay their eggs in the warm sand. The turtle is looking for a suitable place for its nest, the reptile can start digging sand and throw a dug hole several times. The work on the construction of a future dwelling for eggs can last from a few minutes to three hours.
Pregnant red-eared turtles are advised to create the same conditions as their wild relatives. To do this, on the shore of the aquarium, it is necessary to install any plastic container 3030 cm in size, covered with sand 10-15 cm in height. Red-eared turtle eggs laid directly in the water have minimal chances of preserving the viability of the embryos, therefore, if you suspect a turtle’s pregnancy, it is necessary to immediately prepare for their laying.
Towards the end of pregnancy, the female intensively digs the sand offered to her. The female digs the nest with her hind legs, gradually moving in a circle to form an even rounded entrance. To maintain ideal humidity, the female wets the sand with liquid from the cloacal pathways during the construction of the nest. After long efforts, a deep hole with a perfectly flat entrance is formed in the sand, expanding towards the bottom. Having finished with the construction of the nest, the female red-eared turtle lies on its abdomen and lowers its hind legs into the dug hole.
Laying lasts from 5 to 20 minutes, the red-eared turtle lays one egg at a time, after which there is a short respite. After the release of each egg, the reptile lowers its hind legs into the nest and corrects the position of the eggs. At home, a female can lay an average of 10-15 eggs, although their number can vary from 6 to 22 eggs. Red-eared turtle eggs look like white round balls 3-4 cm in diameter.They have a very fragile leathery shell.
Having finished laying, the reptile carefully buries a hole with eggs with its hind limbs, abundantly wetting it with urine. The animal whirls over the nest for 20-30 minutes, sniffs it and tamped it down with its belly. After laying eggs, the reptile happily forgets about its nest. After mating, the female can make 3-4 clutches, so you should not plant her next to the male until autumn. After laying eggs, it is advisable to intensively feed the animal for 2-3 weeks to restore women’s health.
At what age can pregnancy occur
In natural habitat, sexual maturity of red-eared turtles occurs by 6-8 years. At home, the process of puberty is faster, males become sexually mature as early as 3-4 years, and females at 5-6 years. The ideal age for breeding aquatic reptiles at home is 5 years, before attempts to get offspring will be unsuccessful.
It is quite problematic to accurately determine the age of exotic animals, therefore, it is recommended to select individuals for mating according to the length of the shell. Sexually mature males have a shell of at least 11 cm, females already reach 15-17 cm by this age.Until puberty, it is almost impossible to distinguish the sex of animals, all reptiles look like females.
It is possible to determine secondary sexual characteristics in red-eared turtles by comparing several individuals. Males are distinguished by a smaller, elongated shell, an elongated tail and the presence of sharp long claws on the forelimbs. In addition, the characteristic sex of males is a triangular notch at the end of the abdomen. Males sometimes release their penis, which looks like a rose flower, while bathing. After determining the age and sex, it is possible to form heterosexual groups of females and males with a ratio of 2: 1 and wait for the mating games to begin.
Unfortunately, there are no outward signs of pregnancy in reptiles. A pregnant red-eared turtle looks exactly like all other relatives. Most often, the pregnancy of freshwater turtles in the wild occurs in the spring and summer. At home, mating of reptiles most often occurs in the spring in April-May after a long hibernation. During this period, it is recommended to carefully observe the water turtles so as not to miss the courtship process.
Mating games of red-eared turtles are manifested by the male’s active courtship of the female he likes. The boy swims in front of the girl with his tail forward and gently tickles the cheeks of the chosen one with the long claws of his front paws. On land, males can approach females and hit the female’s back with their shells. With the simultaneous maintenance of several different-sex red-eared turtles, males can arrange bloody battles for the right to court the female. In this case, it is recommended to leave a group of several girls and one boy.
Purchase or build an incubator
The incubation temperature of turtle eggs is 26-32C, below and above these boundaries, reptile embryos die. A homemade incubator can be built from a glass jar of sand, installing a heat source and a thermometer in it.
Pregnancy and laying of eggs in red-eared turtles
Simultaneous heterosexual individuals of red-eared turtles at home, provided that optimal conditions are created, can result in pregnancy and childbirth of a female.
A small decorative turtle gives birth to several eggs and this stops her care for the offspring. Lovers of reptiles create ideal conditions for mating animals, take care of the expectant mother and her eggs, from which charming tiny babies of bright green color subsequently appear. To successfully obtain offspring, you need to know how long pregnancy lasts, how red-eared turtles give birth, and what to do if the reptile has laid eggs.
What should be an aquaterrarium for a turtles
It should be quite long, but at the same time not wide and low. The volume is not less than 120 liters. The water level must match the proportions of your turtle’s shell so that it can roll over. A small shore should be equipped near the aquarium. Maintain the water temperature within 25 degrees, on land. 31. 33 degrees. In order for the temperature to remain at a level, a special heater must be provided.
The water must be changed and cleaned depending on the degree of contamination. But you can also use a special filter. For young turtles, external is preferable, and for adults only internal. An ultraviolet lamp does not hurt, but it should not be located low, the approximate height is 25 cm, so that the turtle does not get burned eyes. Another option for arranging an aquaterrarium is an incandescent lamp with the same requirements. They both have to shut down for the night.
If the weather is nice and warm outside, then try to take out the turtles to bask more often. But remember that the first time you do not need to keep it in the sun for more than 5 minutes. And it is important to increase the time spent in the fresh air gradually. They also need a dark place where they can periodically hide from the sun, as they are prone to overheating.
Some guidelines have been developed for maintaining temperature and duration of illumination for all turtles of this species. This is optional, but highly desirable for adults.
So, for the other two turtles from January to March, the temperature should be 18 degrees, and the lighting duration should be 8 hours, April. 21/8, where 21 is the temperature, and 8 is the lighting duration, May. 24/10, June. 27 / 13, July. 28/13, August. 28/11, September. 25/10, October. 22/8, November and December. 18/8.
And for Trachemys scripta troostii the requirements are as follows: January. March. 18/8, April. 20/8, May. 21/10, June. 23/13, July. 26/13, August. 25/11, September. 20 / 10, October. December. 18/8.
Falling into hibernation
Some scientists have argued that Trachemys scripta goes into hibernation and that they need it. But it is quite difficult to imagine this process at home. It would be more logical not to create difficulties for yourself and not cause unnecessary harm to the health of the turtle by organizing hibernation.
Turtles live in shallow lakes with swampy low shores. You can find them in the USA in Florida, Virginia, Kansas, Oklahoma, New Mexico, as well as in Mexico, throughout Central America, in northern Columbia.
Types of feed
From fish it is useful for turtles to eat pollock, gobies, cod, blue whiting and any other, but not fatty. Liver can be beef, and you can also give the liver, chicken heart. From insects and crustaceans: not dry gammarus, earthworms, daphnia crustaceans, crickets without legs, beetles. You can also diversify the food served with the help of small snails, mollusks, squids, frogs, small tadpoles, you should not get carried away with sea products, since any turtle itself is sea. Aquatic plants are not prohibited from plant food: duckweed, hyacinth and others. In addition, it can be dandelion, daisies and any non-poisonous meadow flowers and plants. And vegetables, except for carrots and lettuce leaves, are undesirable.
It is strictly forbidden to give meat turtles to eat: any minced meat, sausages, beef, sausage, lamb, chicken, pork and more. Fatty fish, cheese, fruit and loaf are prohibited. Better to avoid dry food.
If the aquarium is well equipped, has ultraviolet lighting, appropriate temperature conditions, then vitamins can be omitted from the diet. But, in the case when the conditions are far from ideal, then it is imperative to remember about the vitamin and mineral base. For this purpose, vitamins are already included in the feed.
Sexual maturity occurs in females and males in different ways and this is also influenced by their lifestyle. If they are in captivity, then this period begins from 4 years in males and from 5-6 years in females. And in the wild, they reach maturity by about 8 years. Mating season begins in the spring: in the month of March. April. Their process is as follows: the male crawls very close to the female, buries his face in her and tickles her chin with long claws.
The eggs laid do not exceed 4 cm in size. They are laid on land, not in water. But the place for the eggs should be wet, so the female moistens it with water from the anal bladders and then pulls out a small hole. In their nests, turtles. females lay no more than 10 eggs, which are subsequently buried. The incubation period is up to 150 days. An interesting feature with the temperature. If the temperature remains above 30 degrees, then females hatch, and if below 27. males.
What to feed the Tinder turtle
As for young turtles, they need animal food for active vital growth of the body. In this regard, it should be given once a day, but no more. Also, the aquarium should contain a variety of algae and any other plants that are edible for turtles.
Adult turtles are individuals that are much larger than 12 centimeters. They should eat food every two or three days, and half of their diet must necessarily be some kind of vegetation. Any edible plants should be kept in the aquaterrarium for turtles to eat between meals.
The amount of food given is determined based on the size of the turtle. For babies, the norm is two or three pieces of one cubic centimeter, and for older turtles, two or three pieces are several times larger in size.
It is necessary to ensure that the food is at a suitable room temperature and always of a raw consistency. It is important to remember that young turtles are, first of all, predators. Their main food is fish. You can add live fish to the aquarium, which you cannot eat. It is necessary to diversify the given diet and not feed only gammarus and dry food. And adult turtles are omnivorous. They eat both animal and plant foods.
Brief description of this species
The shell of a fairly mature turtle is usually wrinkled. Its length depends on a specific subspecies and, as a rule, reaches 28 centimeters. The red-eared turtle has a small spot near the eyes. A feature is that their colors are diverse and tend to change over the years. Thus, in youth they have a green color, and in old age they are completely black. The abdominal shield of the carapace has a bright yellow color with darkish round spots. The turtle grows as follows: for the first year and a half of life, their growth reaches 7.5 cm, then the rate becomes slower and per year it increases only by 1.25 cm.In two years, growth can be more than 20 cm, that is, it is mistaken to consider it dwarf. And you shouldn’t listen to sellers who convince you otherwise.
Scripta Scripta is about 27 cm long. This turtle has a bright yellow postorbital speck. Her plastron is deep yellow.
Another subspecies. Elegant, has a length of 28 centimeters. The reddish postorbital stripe is located on the head, and there are narrow stripes on the chin. The abdominal shield of the carapace has large specks on all the scutes.
The third species of turtle. Scripta Troostii, has the smallest length of all. about 21 centimeters. On the head there is a narrow postorbital stripe of yellowish color, and on the chin there are wide stripes. And her plastron consists of unusual patterns in the form of “eyes”, and sometimes from ordinary small black specks.
Slow and clumsy? Nothing like this!
Turtles, like humans, rely mainly on their eyesight. The world around them is full of colors
When looking for food, they pay attention first of all to its color and only then to smell and taste. Mediterranean, Balkan and other turtles living on the creature are especially fond of anything that is red. During the experiments, the most attractive to them were red apples and bananas, which they eat, red onions and celery, which they never eat, and even red pieces of wood, paper, plastic
Turtles also favor green, but prefer light greens over dark greens. The slowness and sluggishness of turtles have become proverbs that were invented by people who do not know these animals well. Central Asian, or steppe, turtles, especially often kept at home, climb the mountains to an altitude of 2000 meters above sea level. They walk calmly along the steep stone terraces. Big-headed turtles. inhabitants of streams and rivers flowing among the virgin mountain forests of South China, Burma and the Indochina Peninsula, going hunting, climb the steep banks, along the inclined tree trunks, along the branches. In captivity, box turtles, found in southeastern Canada, east, as well as the central United States and northern Mexico, climb the wire mesh of the corral, which is about 80 centimeters high, when in captivity. I knew a Central Asian turtle that climbed into bed with its mistress and slept under a blanket at her feet. One of the marsh turtles, which escaped from the terrarium, easily climbed the lace curtain to its very top. Turtles become especially nimble when it’s time for love. Male Mediterranean turtles run around, persistently pursuing females, who are looking for salvation from them in the bushes, in the dense grass. However, the males use their shells, knock them on the shells of their chosen ones, bite their legs and force them to leave the shelter. If several males claim the attention of the females, they grab each other by the head, legs and can cause serious wounds. Male American Swamp Turtles do different things for females. Once near their chosen ones, they shake their lowered head from side to side. But their most original number is this: from the mouth and nostrils a stream of water flies out, which exactly hits the physiognomy of the females. Male red-eared turtles look after females even more skillfully. These turtles are the most common inhabitants of the aquaterrari-minds. In nature, they inhabit shallow lakes and ponds with low swampy shores in the eastern United States, as well as in northeastern Mexico. A couple in love is located in the water in a very peculiar way. The female slowly swims forward, and the male directly in front of her. backwards. At the same time, his front paws with long claws are extended forward, and he manages to keep them very close to the head of the female. To top it off, the paws of the male are trembling, and therefore the claws tickle the chin and cheeks of the female.
To ensure that reptiles can reproduce at home, you need to find out what sex each turtle belongs to. Obviously, offspring is obtained by mating a male and a female.
This is interesting: a female reptile can lay eggs without the participation of a male, however, storing them will not give any results, since fertilization in this case was not performed.
Sexual dimorphism in red-eared turtles manifests itself at the age of one year. For comparison, it is recommended to take reptiles of the same age. The distinction between individuals is carried out according to the following criteria:
- body size (females are larger);
- claws on the front legs (in males they are longer);
- tail (longer in the male than in the female);
- the shape of the lower part of the shell (in females. flat, in boys. concave).
My red eared slider laid eggs
The most dangerous day is the first day of life for small turtles. Birds of prey, lizards and animals know when it is time for a new generation to emerge and lie in wait for it on the shore.
Only a few manage to escape, there are cases when all the masonry perished without ever reaching the water. If the baby leatherback turtle was able to reach the reservoir, it begins a measured life.
The main enemy of adult reptiles is man. Pollution of water bodies, illegal capture of reptiles and the development of the tourism business have significantly influenced the number of this species. Often the reptile takes garbage and plastic for food, food is disrupted and the individual dies.
Where eggs are laid
The turtle tries to lay its eggs in places where it will be safe for them. over, this place is located at a significant distance from the habitat of the turtle. Basically, she lays eggs in the sand. The fact is that it is easy to make a depression in the sand, especially since the sand can hold both heat and moisture.
If the mating process is noticed, then it is better to pour a certain portion of sand into the terrarium (aquaterrarium) so that the turtle can lay eggs without much effort. Eggs are laid at a depth of 50 mm, so an island 100 mm high will definitely attract a female.
If a female lays eggs without a male, then they can immediately be thrown away, since there will be no offspring.
European marsh turtle (Emys orbicularis)
Family Freshwater turtles (Emyididae).
Included in the Red Book of the Republic of Belarus.
The proposed modern northern border of the distribution of the marsh turtle in Belarus runs south of the mowing line of the cities of Pruzhany. Belozersk. Telekhany. Dyakovichi. Kopatkevichi. Vasilevichi. Dobrush. The area of modern distribution of the marsh turtle in Belarus covers only the southern and southwestern part of the country, mainly the Polesie region and the zone of European broad-leaved pine forests. Finds farther north at the end of the XIX. early XX century, in recent years have not been confirmed. The main part of the Belarusian population is located in the Gomel and Brest regions, and only a small one. in the southern regions of the Minsk and Mogilev regions, as well as the southern and southwestern regions of Grodno. Regular finds of single individuals and small groups of turtles were also recorded significantly north of the established northern border of the range. in the suburbs of Minsk, Grodno, Zhodino, Orsha, Ushach, in the Berezinsky Biosphere Reserve and some other areas.
The occurrence of the marsh turtle outside the main range can be explained by various reasons. In most cases, especially in the vicinity of cities, they are the result of the release of animals kept at home for some time. This explains the findings of this reptile in the Vitebsk region near the Ambrosovichi and Barankovsk secondary schools of the Shumilinsky region. The origin of most of these turtles, judging by their exterior features, is most likely associated with the southern regions of Belarus. However, some turtles were distinguished by a number of features characteristic of the southern subspecies Emys orbicularis helenica, and were certainly brought from southern latitudes (Crimea).
This species is distinguished by a rather high mobility and quickly inhabits a wide variety of water bodies, gradually settling along the hydrological network, therefore it is possible that turtles gradually penetrate into more northern regions along the river systems of the left tributaries of the Pripyat (Lan, Sluch, Ptich, etc.).
In addition, some of the findings can be explained by the existence of small relict populations that survived in the most favorable places after changes in the boundaries of the range caused by climatic fluctuations. Reproduction in such groups occurs irregularly, only in the warmest years, but the appearance of even several individuals, taking into account the high life expectancy of this species (up to 25-30 years), allows them to exist for quite a long time.
At the same time, the problem of the distribution of the turtle north of the conventional mowing line indicated by S.M.Drobenkov in local relict groups requires study. Repeated oral statements about the capture of turtles in the Vitebsk and Mogilev regions have not been officially confirmed, however, some cases are confirmed by photographic materials, as well as the discovery of a marsh turtle in the north of Minsk region. (see above photo by E. Simankova and A. Kulikov). Again, turtle registrations are not uncommon in more northern Lithuania and Latvia.
Nevertheless, there is reason to believe that the border of the species range over the past 3-7 decades has moved southward by about 100-150 km. There are no exact data on the number of this secretive and now quite rare reptile. Previously, a fairly large number of turtles were observed in the upper reaches of the river. Pripyat, where, for example, in 1925, 250 individuals were counted, which, due to drought, concentrated near lakes and streams. However, large-scale works on drainage reclamation led to the disappearance of typical biotopes of the species and to a decrease in its numbers. For example, in the Minsk region near Nesvizh in 1980-1990. the marsh turtle was a common species in wetlands, and after draining the marshes it became extremely rare.
The only representative of the order of turtles in Belarus. The length of the shell is 16-18 (up to 22) cm, the width is about 13-14.6 cm, the height is 6-8 cm, the body weight is 400-600 (up to 1500) g. The tail is slightly less than half the length of the shell (6.6-7, 4 cm). Comparison with the parameters of the size of the shell of the marsh turtle within the range shows that the territory of Belarus, which is the northern edge of the range, is inhabited by smaller forms than in the southern parts of the range, where turtles have a carapace length of up to 35 cm.
The southern part of Belarus is inhabited by the nominative subspecies, Emys orbicularis orbicularis, which is characterized by the largest size, black coloration, flattened carapace and some other features. The length of the carapace of adult females is from 15 to 21 cm, of males. from 15 to 19 cm.
The dorsal (carapace) and abdominal (plastron) shields of the carapace are interconnected by a movable tendon ligament. In addition, the plastron is divided by a transverse ligament, but the mobility of its halves is barely noticeable. From above, the carapace is smooth and colored in dark olive, yellow-brown or dark gray (to black) tones. On this dark background, small light yellow specks or dashes are scattered. The plastron has a yellowish to dark brown color underneath. Light spots are observed at the junction of the carapace and the plastron. The head, neck and limbs are dark and dotted with small yellow specks.
The sex differences in turtles are quite clear. In the male, a deep indentation is clearly visible on the lower shell; the female’s plastron is completely even. Sexual differences are also manifested in some morphological features (coloration of the neck and tail, the shape of the claws). Males are usually slightly smaller than females of the same age. The age of the turtles can be judged by the number of “annual rings” (as on tree stumps). They are usually seen on the carapace and plastron scutes. However, this method is only acceptable for middle-aged (8-12 years old) turtles. In older individuals, the annual rings merge and differ slightly, which makes it impossible to accurately determine the age. The highest growth rates of marsh turtles were noted in the first years of life, while in individuals of older age groups the growth stops.
The marsh turtle inhabits not very deep calm water bodies (swamps, waterlogged oxbows of rivers, lakes, quiet river backwaters). Recently, she has to develop a number of artificial reservoirs: reclamation canals, fish farms ponds. Sometimes they settle in water bodies near crowded places, for example, in the ponds of the city of Gomel. Currently, the marsh turtle inhabits only about 4.2% of the reservoirs of the Belarusian Polesye, and its number is very low.
Water stations are usually shallow, well-warmed, overgrown with aquatic and marsh vegetation during the growing season with stagnant or slowly flowing water. Typically, the marsh turtle occupies areas of reservoirs with gentle banks or banks with bumps, where it is easy to get out of the water and bask in the sun. Despite the fact that the turtle lives in water, it also loves to go out on land, on which it moves more briskly than land turtles. It does not move far from the reservoir and, at the slightest danger, dives into the water, buries itself in silt or hides among aquatic vegetation.
It is extremely difficult to approach the turtle closer than 5-10 m. Therefore, for a long time it was believed that the marsh turtle is nocturnal, and basks in the sun during the day. However, the turtle usually sleeps at the bottom of the reservoir at night, and during the day it actively hunts not only in the water, but also on the shore. When moving on sandy soil, it leaves a kind of trail: a wide trail from the plastron, on the sides of which there are chains of star-shaped traces from the limbs, as well as an intermittent narrow trail from the tail in the center.
The marsh turtle swims and dives very well and can stay under water for a long time. It rises to the surface of the water every 15-20 minutes to swallow air. Like other turtles, an important adaptation for the development of the aquatic environment (especially for hibernation in water) is a kind of additional respiratory organs: pharyngeal outgrowths rich in blood capillaries and anal vesicles. The complex structure of the lungs allows efficient use of oxygen even with poor ventilation. During hibernation, turtles are under water for several months. This is due to the higher m of oxygen in cold water (about 4 ° C), as well as physiological changes in the body during hibernation. In the experiment, marsh turtles survived in water at a temperature of 18 ° C without access to air for up to two days.
The marsh turtle feeds itself during the day and even at dusk (with breaks for rest). In the water, the turtle catches various invertebrates. insects and their larvae, crustaceans and molluscs, small vertebrates. amphibian tadpoles, small frogs, newts, sometimes fish (mostly sedentary, wounded or sick). On the shore, the marsh turtle hunts mainly invertebrates. beetles, locusts, worms, wood lice, molluscs. In addition, it eats algae and aquatic coastal plants.
Drobenkov (2012) indicates somewhat different hunting behavior and diet for the Polesye population. The marsh turtle feeds exclusively in the water, while terrestrial invertebrates are eaten extremely rarely, usually from the surface of the water, where they accidentally fall. A clear preference for feeding is given to sedentary or attached forms of aquatic organisms, for example, some groups of insects, mollusks, worms, etc.
The food ration of E. orbicularis in the Polesie zone is almost exclusively aquatic invertebrates. The main role in feeding is played by larvae and imago of aquatic insects, the total share of which is 69.8%. Among the food components, gastropods dominate. 20.5%, larvae and adults of aquatic beetles. 13.3%, larvae of caddis flies. 11.1%, as well as larvae and adult swimming beetles. 8.3%. Occasionally, decomposing organic matter is utilized, in particular the corpses of fish and amphibians. In some water bodies, numerous larvae of some common species of tailless amphibians sometimes serve as additional seasonal food. Eating tadpoles of brown frogs. grass and moor frogs, as well as gray toad and green frogs was observed repeatedly in May – June. Vegetation is consumed, obviously, along the way, capturing invertebrates from aquatic plants. Young individuals under the age of 2-3 years, unlike adults, specifically eat blue-green and brown algae, as well as some macrophytes.
Invertebrates with hard chitinized integuments (beetles, dragonfly larvae, etc.), as well as those with calcareous shells (molluscs), play a significant role in the diet of the marsh turtle, which in general is about 35%, which is obviously associated with mineral metabolism and the need for calcification of the shell and bone skeleton. In spring, molluscs, larvae of caddis flies and stoneflies, as well as worms are most often present in food, in summer the composition gradually expands, and the list of groups eaten even in a small reservoir is very significant. The set and quantitative ratio of the main groups of invertebrates in the food of the marsh turtle in various habitats, as a rule, is very similar, which indicates a low selectivity of its diet.
When foraging for food, the turtle uses not only hearing, but also smell. In behavioral terms, the marsh turtle is an inactive predator or, more precisely, a “gatherer”, methodically foraging for food, slowly moving through the reservoir. The average length of its daily movements is about 150-300 m. About 21.1% of the daily time is spent on food and related movements in the reservoir in the summer season.
The trophic period in the marsh turtle in the area of the Byelorussian Polesye lasts approximately 180–190 days and almost completely coincides with the season of activity. Feeding was noted already in the very first days after awakening from the winter torpor, when some stagnant bodies of water were still partially covered with ice. The intensity of feeding, which is determined by the ambient temperature, gradually increases, and from the beginning of May to mid-August it reaches its maximum level, and then begins to decrease slowly. Turtle feeding was observed only during daylight hours.
The marsh turtle is highly sensitive to many environmental factors (temperature, humidity, light) and chemicals (especially proteins), which is caused by the work of a special chemosensory organ located in the head. With its help, she memorizes the smells of her native reservoir, easily finds other reservoirs located at a distance of 1-2 km, and also searches for aquatic invertebrates in a thick layer of muddy bottom silt. Chemotesting behavior in turtles, manifested in the form of movements of the lower jaw, is observed not only on land, but also in water. Apparently, regular throat movements in turtles during land migrations are related to chemotesting behavior that allows them to navigate well in a complex mosaic of terrestrial landscape. Many facts point to the use of chemoreception organs by turtles when “scanning” the area: constant “touching” the substrate by the neck, pauses in wind gusts, correction of directions of movement after tactile contacts, rapid respiratory movements in the pharynx, and some others.
Females, except for some periods. egg deposition, forage migrations and others, are sedentary. They can be constantly seen on the same sites while sunbathing. The turtle spends autumn and winter at the bottom of the reservoir, from about October to April, sometimes until the end of March, and after hibernation, when it gets warmer, it begins to reproduce.
Sexual behavior in E. orbicularis includes the following complex: a) the search for a sexual partner and a short following of the male after the female; b) fixation of sexual partners (amplexus); c) active actions of the male, forcing the female to hide her head under the shell and move to shallow water to ensure breathing; d) copulation, which occurs near the coast and on the bumps protruding from the water.
During mating in the water, the male marsh turtle strongly clings with the claws of the front and hind limbs to the edges and irregularities of the female’s carapace, bending its neck in an L-shaped manner, blowing bubbles, shaking its head sharply, and sometimes violently biting the head and neck of the female, forcing it to hide under the shell. The tail of the male, like a pendulum, constantly slides over the carapace of the female. Copulation occurs in water and lasts up to several hours, sometimes repeats over several days. Individuals that mate often move through the reservoir. Only two heads and a small oval “patch” of the male carapace are visible from the water. During the mating season, the male settles next to the female and does not let her out of sight for a minute.
The mating process was observed exclusively during daylight hours, usually at 11–17 hours, and lasted for about 5–6 hours. For several days, both males and females often mate with different partners. Weather conditions have a noticeable effect on the sexual activity of turtles. During the period of temporary spring cold snaps, which can take 2–3 days, this process dies out, while in steady warm weather, mating is completed in 8–10 fine sunny days. The calendar dates of mating in the zone of distribution of the marsh turtle in the southernmost and most northern regions of the Belarusian Polesye differ insignificantly, by no more than 2–4 days. Mating usually occurs from the end of April to the beginning of May (from 21.IV to 11.V), however, sometimes in the middle of summer, repeated copulation was observed, which was not massive and was noted only in a part of the individuals. Sexually active males and couples in amplexus were recorded in early July (1–11.VII) in various regions of the Belarusian Polesie. The reason for the atypical summer mating has not been established, but it was noticed that it occurs immediately after the second clutch, which develops only in some females.
Pregnancy in a marsh turtle in Belarus lasts about a month (30–35 days), usually from the end of April to the end of May. However, taking into account summer copulation, in some females the period between mating and oviposition can last up to 11 months, covering two seasons, from July of this year to the end of May next. This is due to two reasons. the ability to long-term preservation of viable sperm in the genital tract of females, as well as inhibition of oocyte development during the cold season.
In addition to well noticeable terrestrial reproductive migrations, females also showed less intense water movements. Often, before reaching land, for several days they move along a chain of reservoirs, river beds or canals. Some part of females, approximately 10–12%, stay for 1–2 days in the breeding grounds, which is associated with the search for a favorable nesting site, or is the result of disturbance from predators.
They spend the daytime in dense shaded bushes or under a layer of moss and lichens, where they can burrow very quickly. Often, during the hottest time of the day, they hide in small swamps or temporary rain puddles, which are very common in the immediate vicinity of the breeding station, often at the very foot of the sandy hills.
For short local movements, when the distance from the reservoir to the nesting site does not exceed 300-400 m, it takes from 0.5 to 2-3 hours.
Migrations to more remote hills, located 1.5–2 km away, often begin 2–3 days before laying. During ground crossings, females cross swampy floodplains of forest rivers, bushy and open meadows, fields of agricultural land, forests, farms, as well as highways.
Red Eared Slider Turtle Lays Eggs (Not a guide to build a nest)
Movements of females to breeding sites usually begin in the afternoon, at 15-16 hours, the nest-building process is observed from 20 to 23 hours, and oviposition. at dusk or the first half of the night (from 22 to 1 hour). Return to water bodies occurs immediately after oviposition at night or at dawn. After ground transitions, characteristic longitudinal scratches appear on the turtle’s plastron, which disappear approximately 2-3 weeks after returning to the reservoir.
During the first years, female marsh turtles are able to memorize individual landmarks on the paths of land migration, as well as the features of nesting sites, which allows them to be found faster in the future. Some young females lay eggs near water bodies in unsuitable places (on forest clearings, roads, on the outskirts of fields), and therefore the success of embryo development in such clutches is extremely low.
During the season, the female makes 1-3 clutches of 5-10 eggs each (in May, June, July). Probably the first clutch often consists of eggs fertilized in the last year. Drobenkov (2012) indicates somewhat different data both on the number of clutches and on terms. The main egg-laying season is in late May. early June (20.V–16.VI), however, in the middle of summer (1–8.VII), a second, much less pronounced, period of oviposition is observed. The first clutch is established for the overwhelming majority of sexually mature females (up to 95–100%), while the second clutch, or rather a portion of eggs, develops only in some of them, about 15–20%. The timing of egg laying may vary slightly due to weather conditions.
The number of eggs in the first clutch of female marsh turtle in the Polesie region varies widely. from 8 to 22 eggs (on average, 13.3 ± 0.4). A small part of females (about 15–20%) develop a second, much smaller clutch (more precisely, a portion of eggs), consisting of 1–6 eggs (on average 3.8 ± 0.9).
In the process of building a nest and laying eggs, four main stages can be distinguished: 1) the search for a suitable site, which can take from 15–20 minutes to 2–3 days (usually 30–40 minutes); 2) construction of a nesting chamber (from 20–40 minutes to 1–2 hours); 3) oviposition (usually 1–2 h); 4) burying the nest (5–20 min).
Turtle eggs, like those of birds, are covered with a yellowish calcareous shell. They are usually oval in shape, somewhat elongated in length. Their size is 28-38 x 18-22 mm, weight is 7-12 g (Pikulik, 1988). The total weight of all eggs in the first clutch is 7.2–13.1% of the female body weight. The weight of eggs varies within wider limits (6.05–9.4 g) than the weight of newborn turtles (5.65–6.45 g) (Drobenkov, 2012). The female lays eggs in a hole (on hills, dunes, embankments), which she digs with her hind legs, and then carefully falls asleep. If the soil where the eggs are deposited is hard, then the female moistens it with water from the anal bladders. Eggs are usually laid without vegetation.
Typical breeding areas of the marsh turtle in the Belarusian Polesie, accounting for about 80% of all stations, are open sandy hills or other hills, heights from 1–2 to 13–17 m, with gentle slopes of the southeastern, southern or, less often, southwestern exposure. These are natural (moraine ridges in river valleys, sandy hills in the floodplain zone of water bodies, open forest hills) and artificial hills (dams of irrigation and drainage systems, embankments and roadsides, slopes of waste sand pits, small hills of wastelands among abandoned farmland).
The reproductive biology of the marsh turtle in Belorussian Polesie is distinguished by an interesting, but still poorly studied feature. mass concentrations of females in breeding sites and their seasonal migrations. At present, nesting sites usually lay eggs from 5–7 to 20–25 females, although in some of the most favorable biotopes, larger aggregations of 50–70 females are formed. There are also several unique sites where the total number of breeding females reaches 250-300 individuals.
The breeding season for the marsh turtle in the Polesie region usually lasts 11–15 days, so only part of the females can be found in the egg-laying areas every day. In the first days, only a few individuals are noted, their number gradually increases, after 6-7 days a peak of nesting activity is observed, and then the number of females coming to lay eggs decreases.
The most numerous groups, numbering dozens of females, were found only in large forest-bog areas or floodplain landscapes, with a dense network of various water bodies, but rare open hills. At the same time, small nesting groups (5–10 females) were observed in a wide variety of both natural and transformed landscapes.
Females living in the same water body or in a small area of the river channel lay eggs for a number of years, as a rule, in one common nesting area. Breeding stations are usually the nearest uplands, but in the largest reproductive aggregations, females from distant water bodies located at a distance of 2–3 km or more were often found. Most of the females living in neighboring water bodies gather annually on one hills, probably the most optimal. Numerous flocks of turtles in breeding sites have existed for decades, and some of them have been known for more than 70-80 years.
The average density of turtle clutches in the areas used on the ground station usually ranges from 2-3 to 10 per 100 m², but in some places it can reach 2-3 per 1 m². Cases were repeatedly noted when, during the construction of the nest, one female destroyed the nest and dug up eggs laid by another turtle the day before.
The breeding cycle of the marsh turtle in southern Belarus includes 1–2 annual clutches, which appear to be portions of eggs that develop after ovulation following spring mating. Some features of reproduction were also noted, which relate to the timing of mating, the duration of pregnancy and the timing of oviposition.
Soil temperatures in turtle nests, which are 10–20 cm (usually 13–15 cm) deep during incubation, from late May to early August, typically range from 18–30 ° C. High and stable soil moisture is one of the most important conditions for successful egg incubation. Despite the fact that turtle eggs are covered with a strong calcareous shell, which protects them well from mechanical damage and drying out, the nests are located in the soil layer with constant high humidity (relative humidity 80-100%).
The development of marsh turtle embryos in the zone of the Belarusian Polesie in the hottest seasons lasts 65–70 days, in the coldest and wettest seasons it lasts up to 80–85 days.
Young turtles hatch from eggs only 22-25 mm in size. The very first turtles emerge from eggs in early August, the latest in late August. The spreading is due to the peculiarities of the temperature regime in the breeding sites in the summer, the exposure of the slope, its shade, the depth of the nest, as well as the position of the eggs in the clutch. In addition, it was found that part of the young of the year hatched from the eggs do not leave the nest immediately, but overwinter in the nests of the nesting chamber and settle in water bodies only after wintering, that is, in the spring of the next year. They dig small burrows from the nesting chamber and remain here until the next spring. All this time, they exist due to the reserves of nutrients of the yolk sac, which is on their abdomen, and even grow noticeably. In the spring of next year, young turtles already have a black shell with relatively large yellow spots, much larger than in adults. Having dug out from the shelter, they immediately rush to the reservoirs. By the end of summer, the length of the fry’s shell reaches 40-55 mm, and the mass. 15-25 g. There is information about the dependence of the sex differentiation of marsh turtles on the temperature conditions of embryo development.
The average natural mortality rate of turtles in nests is approximately 15–20% (in different clutches. from 5–10 to 100%). The average yield of viable turtles in clutches in Polesie is 10.1 ± 0.7 wasps.
Due to the high pressure of predators, in the first days of incubation, 15–20 to 50–70% of all nests die (on average, about 40%). According to rough estimates, no more than 5% of the total number of the new generation survives until the spring of next year, and by the age of puberty, the proportion of survivors decreases many times.
Among terrestrial and semi-aquatic predators, the main press is provided by such predators as the fox and the wolf. Other authors (Pikulik, 1988) also indicate a raccoon dog, a badger and a white stork. Semi-aquatic predators, the otter, living together with the tortoise in the same water bodies, as well as the American and, possibly, European mink, rarely use it for food. It is the easiest prey for predators only in the spring during warming up, as well as during the breeding season, when females are forced to make long land migrations.
Unlike adults, young turtles provide affordable food for many predatory mammals, birds, fish and even invertebrates (aquatic arthropods). In Belarus, there were cases of eating marsh turtle underyearlings by domestic dogs, ravens, small passerine birds and even the common viper.
During the incubation season, turtle clutches are very often ruined by some terrestrial and semi-aquatic predators: a raccoon dog, a badger, a wolf, a common chorem, but the main consumer, an oophagous predator, is currently a fox. On average, in Belarus, predators annually destroy about 40% of all laid clutches, and 80% of them are foxes.
The average number (density) of the marsh turtle population in the Polissya landscapes is currently about 3-5 individuals. per 1 km of the river bed, on the same section of the drainage and reclamation canal, 2-3 specimens are usually found, and in small stagnant reservoirs (ponds, low-lying bogs) with an area of 300-500 m2. 2-3 specimens.
The sex ratio in general in Polesie is shifted towards the clear dominance of females (in a ratio of about 1: 2).
Turtles become sexually mature at the age of 6-8 years, while the length of the shell is 9-12 cm, according to other sources at 12-20 years. Considering that marsh turtles live up to 70-120 years, sexual maturity does not come too late.
At the same time, according to new data from Drobenkov (2012), the maximum age of our turtles is much lower. The maximum age of E. orbicularis in Belarusian Polesie reaches 25–27 years. In most males, sexual activity first manifested itself at the age of 8-9 years, with a carapace length from 15 to 15.6 cm. Most females started breeding at a later age. at 9-10 years old, with a carapace length, as a rule, over 16 mm. Sometimes smaller females were found in the breeding grounds during the laying of eggs. Every year, at least 95% of all adult females take part in reproduction and lay fertilized eggs.
The population is characterized by a significant predominance of middle and old-aged individuals, the proportion of young individuals is about 10%.
The annual renewal in the Polesie population is at a very low level, as evidenced by the low proportion of young and clear dynamics of the decline in the number.
Pikulik M.M. (ed.) / Zemnavodnya. Pauzuns: Entsyklapedychny old days (Living light of Belarus). Minsk, 1996240s.
Pikulik M. M., Bakharev V. A., Kosov S. V. “Reptiles of Belarus”. Minsk, 1988166s.
Drobenkov S. M. “Population ecology of the European marsh turtle