When you read or hear about amphibians, it becomes interesting how they tolerate low temperatures? For example, where do frogs winter? There are many ways that amphibians can survive frosts and maintain viability. They are not able to change and regulate their body temperature, but they can adapt to environmental conditions. Frogs cope with this task perfectly. Each family, genus and species of amphibians has its own set of adaptive changes that help to endure cold, frost, drought.
Frogs - inhabitants of reservoirs and wet places
Zoological family These frogs belong to the order Tailless amphibians, the class of Amphibians. In rivers, ponds, lakes and marshes of the
temperate zone, in wet meadows, in gardens and kitchen gardens, there are several common species belonging to the family Ranidae (real frogs), genus Rana (frogs):
- L. lake - R. ridibunda;
- L. pond - R. lessonae
- L. sharp-faced - R. arvalis;
- L. herbal - R. temporaria.
To find out how the frog is preparing for winter, you need to find out the preferred habitat of the species in other seasons of the year. For reproduction, all amphibians need ponds where eggs are laid and tadpoles develop.
Features of frog breeding
The mating season in most amphibians begins in February-March and lasts until the beginning of June. At this time, the male frogs, being in the water, make loud noises. After fertilization, each female is able to lay several thousand eggs. In the form of spherical clusters and ribbons, they float at the bottom or surface of the reservoir. Tadpoles appear from the eggs in a week. The full development cycle from eggs to tadpoles or adults takes several months. Some species become sexually mature only in the second or third year of life. The number of eggs laid by one female can be from 1000 to 12000. Most of them die even before the tadpoles appear. Caviar and young growth become prey for many aquatic animals. Where do frogs and tadpoles hibernate? The choice of shelter depends on the behavior of these amphibians.
Frogs lifestyle
Aquatic amphibians do not move away from their habitats all year round. Overland almost all the time they spend in the marshland, near ponds and lakes, in meadows and in river valleys. Sometimes they can be found far from the water - in settlements, parklands, in the fields. Land frogs go to water bodies mainly during spawning. After its completion, adults leave the ponds and go to places most rich in insects and other invertebrate organisms. In the summer, some species go out only for night "hunting." In spring and autumn it gets cooler, so the daily activity increases. What does a frog do in winter on land when the air temperature drops significantly? The cold-blooded amphibian tries to get deeper into the ground, under the leaves, where it is more likely not to freeze.
How does a frog prepare for winter?
Many amphibians living in water find non-freezing places at the bottom where they can spend the cold season. The largest frogs wintering in the water bodies of Europe belong to the species R. ridibunda. The distribution range of the lake frog is extensive - from the Rhine to Iran. The body of the female reaches 17 cm in length, the males are 5 cm shorter. Green and brown colors and large black-brown spots predominate in color. A light streak passes on the back, and a marble pattern is clearly visible on the abdomen. Lake frogs all the time are in reservoirs, even inhabit deep fast-flowing rivers. What does a frog do in winter? The behavior of a cold-blooded animal depends on the climate of the area and weather conditions.
The lake frog begins to prepare for hibernation at a water temperature of about 6–9 ° C. With further cooling, adults and tadpoles burrow into the bottom sludge. At the bottom of lakes, rivers and deep ponds, they spend the whole winter, while breathing through the skin.
Where do land frogs hibernate?
Land
frogs are grass and moor
frogs (marsh). Species R. temporaria in body size is inferior to R. ridibunda. Its length does not exceed 11 cm, the top is brown with dark stripes, the abdomen is grayish-white. This is one of the most common amphibians in the northern and middle strip of Eurasia. How to prepare a frog for winter with a land lifestyle? With the onset of autumn cold, the search for a secluded place begins. For wintering, the frog is suitable:
- pits with a bunch of foliage;
- mink rodents and voids in the ground;
- rotten stumps;
- large stones;
- low hollow trees;
- basements.
How amphibians from the family of tree frog or woody (Hylidae) spend their winter?
Tree frogs are small tailless frogs, usually green in color. They live on trees and shrubs, clinging to the bumps of the bark with suckers on their legs. Tree frogs go down at night in search of food, but for breeding they prefer to find accumulations of moisture in tree hollows, leaf sockets. The wintering of woodfrogs differs from the wintering of aquatic amphibians. In terms of lifestyle, they are more reminiscent of the land representatives of the Ranidae family. The following species of the Kwakshi genus are most common in central Russia: K. ordinary, K. Asia Minor, K. Far Eastern. In autumn, the woods burrow into the forest litter, hide in hollows, burrows, under stones. Before the winter begins, the amphibian coloration darkens, more carbohydrates are produced in their body, which protects them from death in cold weather. In spring, tree frogs are thawed and set off to look for places for spawning.
Why don't cold-blooded amphibians die from frost?
Where do the frogs living on land and in water disappear for the winter? Land species in autumn try to get deeper into the ground, under the leaves, where there is more chance of not freezing. Some amphibians hibernate. Before the frogs enter rest mode, they must find a suitable place to hibernate both on land and in water. In the cold months they lie motionless in their shelters, being at rest. In sleep mode, all life processes in the body slow down. The temperature in the winter shelter may drop to minus points. Timber sometimes remain alive even after freezing. The role of "antifreeze" are carbohydrates in the blood and urea. Representatives of other families may die from frost. With the onset of the first heat at the end of winter and at the beginning of spring, the frogs at rest begin to return to their usual life.
The Importance of Wetlands for Frogs
For winter shelters of amphibians, bottom silt, driftwood, and clusters of plants are used. In winter, land frogs in the temperate zone hibernate, finding secluded places for this. In spring and summer, they need water for reproduction. After winter dormancy, when it gets warmer, they head for lakes and ponds. The process of mating, spawning and development of tadpoles takes a long period of time. In many land species, the mating season begins on the way from wintering sites to spawning grounds. Interestingly, females sometimes help males to bear the hardships of travel, carrying them on their backs. Frogs spawn in bodies of water with stagnant water, choosing any suitable places for this purpose: ponds, ditches and puddles. The name of the class “Amphibians” recalls the role of the habitat for this group of animals. Many types of amphibians live in lakes, rivers, and swamps. They feed on insects that are found in ponds, themselves serve as food for larger animals. Thus, frogs are an important part of the food chain.
Adaptive Amphibian Mechanisms
Having found out what the frog does in winter, it can be argued: adaptation to environmental conditions is very important for them. Species that live in the northern part of the temperate zone are especially hardy. Significant changes occur in the organisms of wintering amphibian species:
- blood glucose levels increase;
- the concentration of urea in the body increases;
- organ systems slow down or stop working;
- motor activity ceases;
- no breathing;
- heart does not beat.
Scientists rate the role of urea in adaptation highly. An increase in its content may serve as a “trigger mechanism” for transitioning to a state of hibernation. Adaptations in the form of deep dormancy are found not only in species living in forest and steppe zones. Just as frogs winter in the temperate zone, tropical amphibians spend a hot and arid season. There are advantages in this lifestyle. Amphibians do not have to spend energy to fight cold or heat.
It doesn’t matter where the frogs hibernate. Almost all of them, after a state of rest, remain viable and immediately begin to reproduce.