Turtle in the desert. Desert animals. Central Asian tortoise – description and photographs
It’s not for nothing that scientists call natural conditions deserts are extreme, i.e. extreme. One is always in abundance here, the other is lacking. The main thing that is sorely lacking in the desert is moisture. Less than 170 mm of precipitation falls per year, and for many months the merciless sun shines from a cloudless sky - not a drop of rain falls on the parched land. But the desert does not lack warmth and sun. During the day, the air temperature rises to 45-50°, in some areas of the tropics - even up to 58°, while the surface of the earth heats up to 80-90°.
Lack of moisture and drying heat prevent rich vegetation from developing in deserts. Only on short period rains, lasting one to two months, some deserts are transformed: on the sand or on the clay surface appears green cover. It is at this time that insects and reptiles lay eggs, birds build nests, and mammals give birth to their young.
How do desert animals manage to adapt to harsh temperatures, to the lack of moisture, to life on soil almost free of vegetation?
No animal can tolerate prolonged overheating. If you leave a lizard or rodent gerbil in the sun during the day, then literally in a few minutes they will die from sunstroke. Desert inhabitants escape from the scorching rays of the sun in different ways. Many of them - jerboas, geckos, sand boas, darkling beetles - lead night look life. During the day, when the sun burns mercilessly, these animals find refuge in deep, cool burrows.
Animals that live during the day are active only in the early morning hours, when the soil has not yet become hot. And when the sun rises higher and its rays turn the surface of the earth into a frying pan blazing with heat, they look for shady, cool shelters. Daytime lizards - foot-and-mouth lizards, agamas, roundheads - climb into rodent burrows, bury themselves in the sand, or climb onto the branches of bushes, where the temperature is noticeably lower than in the hot ground layer of air. Mammals also hide in burrows or hide in the shade of bushes and rocks. Small birds - desert sparrows, dun finches - prefer to build nests in the shade to protect themselves and their offspring from overheating. Therefore, they willingly settle under the huge nest of the desert raven or golden eagle. Under it, like under an umbrella, there are 3-5 nests of small passerine birds.
Desert inhabitants have adapted differently to obtain the water they need for their bodies. Desert birds fly tens of kilometers away to drink - sandgrouse and pigeons. Desert inhabitants, who do not have such mobility, have to find water in a roundabout way. Thus, herbivorous animals - darkling beetles, rodents (gerbils and gophers), antelopes - extract water from the succulent parts of plants - leaves, green twigs, rhizomes and bulbs. Desert animals have a number of physiological adaptations to conserve water.
Central Asian turtle.
In order to move quickly on loose sand, sand desert animals have various adaptations. On the legs of many lizards and insects, scales or bristles form special brushes. These brushes provide good support when running on the surface of the sand. The reticulated foot-and-mouth disease rushes with lightning speed from one bush to another, leaving a chain of footprints in the sand. If you pick up this agile lizard, you can see a comb of horny scales on each toe of its paw.
Large gerbil.
Mammals living among shifting sands have densely furred paws and thick hairs on their soles. It is not for nothing that two types of jerboas are called “hair-footed” and “comb-toed”. These animals run superbly along the slopes of sand dunes, their furry feet do not sink into the loose sand. Even such a huge animal as a camel, despite its impressive weight, moves easily and smoothly across the sandy “sea” - indeed a “ship of the desert”. The soles of his feet are flat and wide. And this heavyweight walks along the dunes much easier than a light horse, whose narrow hooves sink deep into the sand.
Snakes in sandy desert It is also inconvenient to crawl in the usual way: there is no solid support for the writhing body. Some species of desert snakes have developed a special “sideways move.” The snake does not crawl forward, but rather shifts one half of its body to the side, slightly lifting it above the ground, and then pulls the other half towards it. This is how we move in the Karakum Desert sand faff, V South Africa- tailed viper, in the deserts of Mexico and California - horned rattlesnake.
Thin-toed ground squirrel.
It is not easy to dig a hole in the sand if it is dry and crumbles immediately. But it’s easy to just bury your head in such sand, and not every predator will guess where its prey went. Many inhabitants of dunes use this method of protection, burying themselves in the sand in a few seconds. This is what the long-eared and sandy roundheads do. They seem to “drown” in the sand, throwing it away with vibrating body movements. And other animals simply crawl in the thickness of the sand, for example, the sand boa from the Karakum desert or the pygmy viper from the Kalahari Desert.
Eared roundhead.
Thus, we see that in harsh conditions desert animals find ways to escape the heat, get the necessary moisture, and use the special properties of the soil. Therefore, despite the harshness of nature, the desert is quite richly populated by various animals. The most typical inhabitants of deserts are reptiles. These animals, more than birds or mammals, are able to withstand drought and fall into an inactive state for many weeks and even months.
Varan
One of the most common desert animals is turtles. The activity period of Central Asian steppe tortoises is very short - only 2-3 months a year. Coming out in early spring from wintering burrows, turtles immediately begin to reproduce, and in May - June, females lay eggs in the sand. Already at the end of June you will hardly see turtles on the surface of the earth - they all burrowed deep into the soil and hibernated until next spring. Young turtles, emerging from eggs in the fall, remain overwintering in the sand and come to the surface only in the spring. Central Asian turtles feed on all kinds of green vegetation. They live in the deserts of Africa different kinds land turtles are the closest relatives of our Central Asian turtle.
Snake arrow.
Lizards can be seen everywhere in the desert. Foot-and-mouth disease and roundheads are especially numerous. In our clay deserts live the takyr roundhead and multi-colored foot and mouth disease, and in the sandy deserts live the sandy and long-eared roundhead, reticulated and striped foot and mouth disease.
Young goitered gazelle.
The sandy roundhead is a tiny lizard with a sandy-yellow back and a tail striated underneath. Lizards curl and unwind their striped tails when excited. During the hottest hours of the day, the roundhead runs into the shade of small bushes. If you persistently pursue a lizard, it will lie flat on the sand and, rapidly vibrating its entire body across the axis of the body, “drown” in the sand in a few seconds. Many predators are deceived by such an unexpected maneuver.
A scarab beetle drags a ball of dung into its burrow.
Among the powerful sand dunes, overgrown with only isolated bushes, lives a large eared roundhead. In the hottest hours of the day, the long-eared roundhead runs along the sand, raising its body high on widely spaced legs. At this time she resembles a small dog. This position protects the lizard’s belly from being burned by the hot sand. Noticing dangerous enemy, the long-eared roundhead runs to the other side of the dune and burrows into the sand with lightning speed using lateral movements of the body. But at the same time, she often leaves her head above the surface in order to be aware of further events. If the enemy is too close, the lizard goes on active defense. First of all, she vigorously twists and unwinds her tail, which is colored velvety black below. Then, turning to the enemy, he opens his mouth wide, his “ears” - skin folds in the corners of the mouth - straightened and filled with blood. It turns out that the fake “mouth” is three times wider than the real mouth. With such a frightening appearance, the lizard lunges towards the enemy, and at the decisive moment grabs him with sharp teeth.
Sandy efa.
On the slope of a dune overgrown with saxaul; occasionally you can see the most large lizard deserts - gray monitor lizard. It reaches a length of 1.5 m and weighs up to 3.5 kg. Nearby you can see a hole more than 2 m deep, where this “desert crocodile” hides when in danger. Rodents, lizards, snakes, and even beetles, ants and caterpillars serve as food for the monitor lizard.
Phalanx.
Some lizards in deserts have adapted to a nocturnal lifestyle. These are different geckos. One of the most remarkable representatives of nocturnal lizards is the skink gecko, which inhabits deserts. Central Asia. He has a large head with huge eyes, which have a slit-like pupil and are covered with a transparent leathery film. Having emerged from its burrow in the evening, the gecko first of all licks both eyes with a wide spade-shaped tongue. This removes dust and grains of sand that have settled on the leathery film of the eye. The skink gecko's skin is soft and translucent. If you grab it, flaps of skin easily come off the lizard's body. An even smaller, more graceful and fragile gecko is the crested gecko. Its body is so transparent that the bones of the skeleton and the contents of the lizard’s stomach are visible through the light. Our geckos have ridges of scales on their legs that make it easier for them to move along the sand. But the web-toed gecko from the Namib sand desert in South Africa has an even more unique adaptation. It has webs between its toes, but not for swimming, but for walking on sand.
Skink gecko.
The sandy deserts of Australia are home to one of the most bizarre lizards - the moloch. Her entire body is covered with sharp spikes sticking out in all directions, and above her eyes two large spikes form “horns”. The skin of the moloch absorbs water like blotting paper, and after rare rains the weight of the moloch increases by almost a third. The water accumulated in this way is gradually absorbed by the animal.
In South Asia and North Africa, various species of spinytails live on dense, gravelly soils. These lizards are equipped with a thick, spine-covered tail, which they use as a defensive weapon to strike. In the body cavity of the spiny tail there are special bags in which water is stored. It is gradually consumed during the dry period.
There are many snakes in deserts, some of them poisonous. IN Australian deserts Aspid snakes are common in the deserts of America - rattlesnakes, and in African and Asian deserts viper snakes predominate. For Central Asian deserts characteristic arrow-snake, sand boa, sand epha.
Tarantula.
The arrow-snake was named so for the extraordinary speed with which this elegant, thin light brown snake moves. Rushing after the lizard, it really resembles an arrow fired from a bow. During the day, the arrow-snake often climbs onto the branches of bushes, from where it tracks prey. The arrow snake has poisonous teeth at the back of its upper jaw. But its bite is not dangerous for humans - the back teeth do not reach the skin when biting.
The sand efa leaves a mark on the sand in the form of separate oblique parallel stripes - after all, it moves “sideways”. This is a small, dense, sand-colored snake with large light spots across its back. When in danger, it curls up into a double crescent and, sliding one side against the other, makes a loud sound by rubbing the pointed side scales against each other. The epha's food consists mainly of gerbils, in whose burrows it settles, and the young ephas eat scorpions, locusts, and centipedes.
In the first half of the night, a sand boa is often encountered in the desert. This snake is well adapted to life in thick sand: its head is sand boa it is pointed like a spade - this makes it easier to break through the soil, and the eyes are placed on top of the head so that, slightly sticking its head out of the sand, the snake can inspect the surroundings. The boa strangles its victims with rings muscular body, justifying family ties with giant boa constrictors of the tropics. The menu of the sand boa includes both diurnal animals, which it finds sleeping in the sand, and nocturnal animals, which it catches on the surface.
Insects are not as visible in deserts as reptiles, but they also form the basis of the animal population of deserts. Most of all there are beetles in deserts. ^It is especially common to see a variety of darkling beetles. These beetles are usually black, sometimes with white dots or stripes; they cannot fly - they only crawl and run on sand or rubble, sometimes climbing onto the lower branches of bushes. Darkling beetles can cause great damage to plantings in deserts: after all, their food consists of all kinds of vegetation. Most darkling beetles are active at night.
You can often see beautiful beetles on the branches of bushes in the desert - black, green-golden beetles. And at night, large whitish beetles - snow beetles - fly into the light of the lantern. The larvae of all these beetles feed on the roots of shrubs.
There are a lot of ants in deserts, but their anthills do not rise above the ground, as in the forest. Usually only the entrance to the underground anthill is visible; ants scurry back and forth all the time. Desert ants, the phaetons, are especially funny; they run on long legs with their abdomens raised high. The pale slider ant, which lives in quicksand, quickly buries itself in the sand at the slightest danger.
Various mosquitoes and mosquitoes spend the day in gerbil burrows, hiding from the heat. With the onset of darkness, they fly out of their holes, and the females look for victims among warm-blooded animals, mainly rodents. There are few arachnids in deserts, but they are very characteristic of these places. In both sandy and clayey deserts you can find various types of spiders, scorpions, and phalanges. The tarantula spider lives in a hole that it digs itself. He strengthens its walls with cobwebs so that they do not crumble. The tarantula sits in its burrow all day, and at night it comes out for prey - small insects. The tarantula has a whole set of eyes - two large and six smaller ones. Under the lantern his eyes glow from afar green light. Large smoky phalanxes often come running into the light of a lantern at night. These are agile animals up to 7 cm long, with long hairy legs. Phalanges are omnivorous, feeding on any small thing they can catch, and they can deftly dig out prey from the thickness of the sand. Contrary to popular belief, phalanges are not poisonous.
Deserts are home to groups of rodents characteristic of these landscapes - gerbils and jerboas. Gerbils are diurnal or twilight image life, settle in entire towns - colonies. Colonies large gerbils- This is the epicenter of life in the desert. The burrows of gerbils are used as shelter by lizards, snakes, and insects; predators that feed on gerbils, such as monitor lizards, ferrets, and ephs, also settle here or nearby.
Jerboas inhabiting deserts North Africa and Asia, are typically nocturnal animals. Their big eyes big ears talk about the high development of hearing and twilight vision. The front legs are small, and the hind legs, which are jumping, have an elongated foot. The tail is usually longer than the body and serves the jerboas both for balance when jumping and as a steering wheel on sharp turns. Having climbed into a deep hole for the day, the jerboa plugs the entrance to it with an earthen plug - a “penny”. Among the jerboas, five-toed ones (they live in clayey and gravelly deserts) and three-toed ones are clearly distinguished - they have feet with a hair brush and they live in sandy deserts. Jerboas and gerbils serve as food for various four-legged and feathered predators. They are hunted by the desert owl, the golden eagle, the fox, and the sand cat.
Large mammals are rarely seen in the desert, but here and there their tracks are visible. More often than others there are traces of desert hares, very rarely - traces of the desert lynx caracal. Some antelopes live in the desert. The gazelle is characteristic of the deserts of Central Asia; in the deserts of the Arabian Peninsula, Central Asia and Africa there are other gazelles.
There are few birds in deserts. Only occasionally will you hear the simple song of a crested lark or the alarming cry of a dancing wheatear. Saxaul jays live sedentary among the dunes - birds with loose, lush gray-fawn plumage, which protects them well from overheating. These restless birds notice the appearance of a stranger from afar and notify everyone with loud chirping, replacing our restless magpie. Saxaul jays fly reluctantly, right above the ground, but they run superbly, with wide, sweeping steps.
White-winged woodpeckers make hollows in the trunks of desert bushes, and after them saxaul sparrows can settle there. Desert owls nest in the walls of wells and hide from the heat of the day. Many desert birds do not consume water at all and never fly to drink. This is how the desert sparrow, the warbler, and the saxaul jay behave. But some birds penetrate deep into the desert only enough to periodically fly to watering places. Near a reservoir in the desert you can see finches, saxaul sparrows, doves and hazel grouse arriving here.
In our deserts there are black-bellied and white-bellied sandgrouses, as well as their relative - the sajja, or hoof; her toes are fused into a solid scaly foot. There are especially many sandgrouse in Africa, right up to the Kalahari Desert. Sandgrouse are exceptionally good flyers; they have long, pointed wings. Therefore, they can nest even several tens of kilometers from bodies of water, flying there to drink. Having flown to a reservoir, they sit on the shore in a noisy flock, enter the water and drink quickly and greedily, without lifting their beaks from the water - they suck water into their stomach. But then they go even deeper into the water and diligently wet their chest plumage. Why is this? It turns out that, having flown to the nest where thirsty chicks are waiting for them, the parents allow them to suck water from the moistened breast feathers.
Desert life hides many mysteries. There are also animals there that are very little known or not known at all to science. And knowledge of the desert animal world is necessary for people to successfully develop rich natural resources these harsh places. After all, the desert is both pasture for sheep and hunting grounds. In order to skillfully master it, you need to have a good understanding of all the subtle and hidden connections that exist between desert vegetation and the animals that eat it, between predatory and herbivorous animals, and to foresee the changes that human activity will cause in the desert.
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Reproduction and development There are 2-7 eggs in a clutch. The eggs are spherical, slightly oval, 39-49 mm long. Incubation period at a temperature of 30-31°C and a humidity of 50-60% it is 80-130 days. Turtles are born in the fall. They weigh 23 g with a shell length of 48 mm. They reach sexual maturity at 15-20 years, and the life expectancy of these gophers is up to 50 years (according to other sources, up to 80). In 1963-1973, the growth dynamics of turtles were studied in Nevada. On average, gophers grew 9 mm per year. The fastest growth was observed in April-July.
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Diet Western desert gophers feed on green vegetation with a high moisture content: various grasses, leaves of shrubs, fruits and prickly pear flowers. In the wild, they rarely manage to drink water, but if possible, they are able to drink so much in one sitting that their weight increases by 40% (other desert inhabitants, camels, have a similar ability).
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Behavior They dig holes for themselves up to 14 meters long. In dry years in hot weather summer time The activity of these turtles is decreasing. In the north of their range, in Utah, gophers spend the winter in groups in their own deep burrows. Further south, in Arizona, they use deep burrows for wintering. prairie dogs. In Sonora, where winters are mild, gophers do not spend the winter at all. Utah tortoises regularly make seasonal migrations between wintering refuges at the base of the hills and summer feeding grounds on the plains.
The desert tortoise is a medium-sized species of tortoise that lives in the southwestern desert regions North America and parts of northern Mexico. Desert tortoises are best known for their tall, dome-shaped shells and for their ability to most their lives in holes underground. This land species turtles that have adapted to survive in the very harsh conditions of an arid desert climate.
Desert tortoises inhabit the vast sandy plains and rocky foothills that lie in and surround the Mojave and Sonoran Deserts. When the temperature is too hot for the desert tortoise, it simply digs a hole in the sand where it can stay cool until the heat subsides. To survive, they require soft, dig-able soil with low-growing vegetation.
The desert tortoise has a number of biological adaptations that allow it to survive more successfully in such arid conditions. The front legs of the desert tortoise are heavy and flat in shape. This feature, combined with a set of strong, short and wide claws, gives the desert tortoise the ability to climb and scale rocks very effectively, as well as quickly dig deep holes in the ground to find water, food and create underground burrows. The desert tortoise's shell is a hard bony shell that protects the animal's body from overheating and attacks from possible predators. Its length is 23-37 centimeters.
Like other tortoise species, the desert tortoise is a herbivore, feeding only on organic plant matter. Grasses make up the majority of the desert tortoise's diet, along with wild flowers of the prickly pear cactus, as well as rare fruits and berries that can be found in harsh, hot climates. These turtles rarely have the opportunity to drink water, so if they manage to find a source of moisture, they drink as much as they can at one time, and their weight due to the water they drink can increase by as much as forty percent. Turtles of this species, like camels, are able to retain the moisture they drink in their body for a very long time. 
Because of their small size, desert tortoises have amazing a large number of natural predators, despite their hard shell. coyotes, wild cats, some reptiles and predator birds They are the main predators of the desert tortoise along with the serpentine lizards.
The desert tortoise's breeding season occurs twice a year, in the spring and again in the fall. The female desert tortoise lays about 6 or 7 eggs, although the size of one egg-laying may be larger or smaller. These eggs hatch after a period of several months and the young turtles learn independent life and survival in harsh desert conditions.
Due to the destruction of natural habitats and the constant capture of desert tortoises by people, their population is constantly declining. However, conservationists are fighting to preserve this species, and today desert tortoises successfully live and breed in many American zoos and nature reserves.
- Class: Reptilia = Reptiles
- Order: Testudines Fitzinger, 1836 = Turtles
- Family: Testudinidae Gray, 1825 = Land turtles
- Species: Gopherus agassizii = Western desert tortoise
Species: Western desert tortoise (Gopherus agassizii)
The most common species in collections is the western desert gopher (desert tortoise). It inhabits the deserts of southwestern Utah, southern Nevada, southeastern California and western Arizona. In Mexico, the turtle is found in the Sonoran Desert. Prefers areas with bushes and soil suitable for digging holes, which can be up to 12 meters long. Depending on the climate, they can go to winter (colonies of wintering reptiles are often observed) or remain active all year round.
This species has a high, dome-shaped carapace up to 38 centimeters long. The carapace is brown and has a pattern, the plastron is yellow. Males have greatly elongated throat scutes, which are used by the animals in ritual fights during the breeding season. Strong, elephant-like forelimbs allow turtles to learn how to sandy deserts, and mountain slopes.
For an adult desert western gopher A large terrarium is required, commensurate with its dimensions. In the hot season (it’s easier to do this in the southern regions), turtles can be kept on outdoors in compliance with standard rules: the presence of warm shelters and protection from predators. The enclosure must be fenced with a strong fence, and, given the ability of turtles to dig holes, the fence must be buried at least 15 centimeters into the ground. The shelter can be arranged either in the form of a booth or in the form of a hole with reinforced walls. The tunnel width should be larger size turtle shell by 10-12 centimeters. The nesting chamber should have a removable lid to make it easier to remove animals from the shelter. When making it, you need to keep in mind that the turtle should turn around freely in the “bedroom”. There must be a pond in the enclosure, but it cannot be made deep: desert animals cannot swim and can drown.
A terrarium for young animals can be small, about 70-100 centimeters (70-150 liters) long. The air in it should be very dry. Therefore, it is necessary to make a large number of ventilation holes in the lid; it is better to make it mesh. The daytime temperature in the warm corner of the room should be maintained within 31-35 "C, in the cool corner - about 22-25 "C. There is also a shallow pond and shelter. The night temperature in a warm corner should be about 21-24 "C. It is mandatory to install lamps like "Repti Glo" or others that are a source of ultraviolet rays.
The natural food of the desert gopher is various grasses, leaves of shrubs, fruits and flowers of prickly pear. They are all high in fiber and low in moisture. Animals kept in captivity should also have similar food (however, most domestic hobbyists are unlikely to be able to grow cacti in the required quantity). Among the plants fed there should not be poisonous ones (buttercups, oleander and some others). They diversify the diet of turtles with lettuce leaves, cabbage, various vegetables and fruits. Feeding alfalfa hay is also a good idea.
This species is successfully bred in some zoos in the United States. Turtles lay two to seven eggs.
In addition to the desert gopher, three more species are known: Texas (Gopherus berlandieri), Mexican (Gopherus flavomarginatus) gophers and polyphemus gopher (Gopherus polyphemus).
Their living conditions differ little from those recommended for the desert gopher. Their breeding is poorly developed
"Land turtles". A.N.Gurzhiy
Most often found in collections western desert gopher (desert tortoise). It inhabits the deserts of southwestern Utah, southern Nevada, southeastern California and western Arizona. In Mexico, the turtle is found in the Sonoran Desert. Prefers areas with bushes and soil suitable for digging holes, which can be up to 12 meters long. Depending on the climate, they can go to winter (colonies of wintering reptiles are often observed) or remain active all year round.
This species has a high, dome-shaped carapace up to 38 centimeters long. The carapace is brown and has a pattern, the plastron is yellow. Males have greatly elongated throat scutes, which are used by the animals in ritual fights during the breeding season. Strong, elephant-like forelimbs allow turtles to explore both sandy deserts and mountain slopes.
An adult western desert gopher requires large terrarium, commensurate with its dimensions. During the hot season (this is easier to do in the southern regions), turtles can be kept outdoors, subject to standard rules: the presence of warm shelters and protection from predators. The enclosure must be fenced with a strong fence, and, given the ability of turtles to dig holes, the fence must be buried at least 15 centimeters into the ground. The shelter can be arranged either in the form of a booth or in the form of a hole with reinforced walls. The width of the tunnel should be 10-12 centimeters greater than the size of the turtle's shell. The nesting chamber should have a removable lid to make it easier to remove animals from the shelter. When making it, you need to keep in mind that the turtle should turn around freely in the “bedroom”. There must be a pond in the enclosure, but it cannot be made deep: desert animals cannot swim and can drown.
A terrarium for young animals can be small, about 70-100 centimeters (70-150 liters) long. The air in it should be very dry. Therefore, it is necessary to make a large number of ventilation holes in the lid; it is better to make it mesh. The daytime temperature in the warm corner of the room should be maintained within 31-35 "C, in the cool corner - about 22-25 "C. There is also a shallow pond and shelter. The night temperature in a warm corner should be about 21-24 "C. It is mandatory to install lamps like "Repti Glo" or others that are a source of ultraviolet rays.
The natural food of the desert gopher is various grasses, leaves of shrubs, fruits and flowers of prickly pear. They are all high in fiber and low in moisture. Animals kept in captivity should also have similar food (however, most domestic hobbyists are unlikely to be able to grow cacti in the required quantity). Among the plants fed there should not be poisonous ones (buttercups, oleander and some others). They diversify the diet of turtles with lettuce leaves, cabbage, various vegetables and fruits. Feeding alfalfa hay is also a good idea.
This species is successfully bred in some zoos in the United States. Turtles lay two to seven eggs.
In addition to the desert gopher, three more species are known: Texan (Gopherus berlandieri), Mexican (Gopherus flavomarginatus) gophers and gopher polyphemus(Gopherus polyphemus].
Their living conditions differ little from those recommended for the desert gopher. Their breeding is poorly developed
"Land turtles." A.N.Gurzhiy
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