Common Frog (Rana Temporaria)

2023 Author: Molly Page | [email protected]. Last modified: 2023-11-27 22:49

The common frog, or the common frog, or the European frog (Rana temporaria) is one of the most widespread in Europe, where it inhabits forests, the shores of water bodies, wet swampy places, forest-steppe, steppe. The voice of male grass frogs is similar to a quiet purr. In 2005 it was introduced in the south of Kamchatka. Adult frogs feed on land. Active at dusk and at night. One female lays 670-1400 small eggs. In Europe, her paws are considered a delicacy.

Area

Europe (except for the Iberian Peninsula), in the north reaches the limits of the continent, the southern borders of the area - the south of France, Italy. In the east, the range reaches the Urals. It rises up to 4000 m in the mountains.

Sharp-faced frog (Rana arvalis), photo photograph of an amphibian

Appearance

The common frog looks like a sharp-faced frog, but larger than the last. There are three subspecies: Rana temporaria temporaria, Rana temporaria honnorati (lives at the foot of the Alps) and Rana temporaria parvipalmata (lives in northwestern Spain and the Pyrenees). The muzzle is blunt, the body is squat. The eyes are brown with black horizontal pupils. The inner eyelid is transparent and protects the eyes in water. A dark brown triangle is clearly visible near the tympanic membrane.

The frog's skin is slimy and smooth to the touch, its epidermis is not keratinized. The dark belly has a marble-like pattern. The inner calcaneal tubercle is low. Females are larger than males. In the mating season, the male's throat turns blue, and four-part black rough tubercles appear on the first toe of the forelegs. The common frog is not afraid of the cold, therefore it wakes up earlier than other frogs, but it is more sensitive to heat and humidity.

Common frog, common frog (Rana temporaria), photo amphibian photo pixabay

Color

The color of frogs varies depending on the habitat: gray, brown, brown with large and small spots. Males are colored darker than females. There are albinos with red eyes. Some individuals turn blue during the breeding season. In Scotland, there have been cases of finding completely colored individuals in red or black.

The size

Adult frogs do not exceed 6-10 cm. The average weight is 22.7 g.

Article on the topic The content of the grass frog (Rana temporaria)

Life span

In nature, grass frogs live for 4-5 years, in captivity - up to 18 years.

Vote

The voice of male grass frogs is similar to a quiet purr (with a force of 400-600 Hertz), which can be heard only at a distance of up to 50 meters.

Habitat

Forests, shores of reservoirs, wet marshlands, forest-steppe, steppe.

Common frog (Rana temporaria), photo amphibian photo pixabay

Enemies

Birds feed on caviar of common frogs: gray duck, witch, mallard, moorhen, great bodew, black tern, common newt. The tadpoles are hunted by: Roller, Magpie, Field Thrush, White-browed Thrush, Swimming Beetle and its larvae. Adult frogs are eaten by: common gull, black stork, goshawk, saarich, wasp eater, spotted eagle, marsh harrier, eagle owl, owl, raven, gray shrike, shrike, vipers. Sometimes (in spring) wolves eat frogs.

Nutrition / food

An adult grass frog feeds on land, while offspring - in water. Most of the diet of adults is made up of beetles (up to 73%) and Diptera, less - terrestrial mollusks and Orthoptera. The intensity of nutrition is not the same at different times of the year. Does not feed during the breeding season.

Common frog, common frog (Rana temporaria), photo amphibian photo

Behavior

On cold nights, the common frog is inactive. It is active at dusk and at night, but in cloudy weather and in humid shady places it is also active during the day. The highest activity occurs from 11 pm to 2 am, and drops to a minimum by 11 am. Leads a secluded lifestyle most of the year. Spends all summer on land, moving away from water bodies for considerable distances. Avoids salt water bodies and cannot live more than a day in water, the salinity of which reaches 0.07%. During the day, he sits hiding in dense bushes, under stones, in stumps, in dense grass, where there is more moisture. Sits, pressed close to the ground, in a state of slight numbness. With the onset of regular frosts (the average daily air temperature drops below 6 ° C), activity stops.

Common frogs are grouped in places close to their future hibernation: in swampy areas adjacent to water bodies, in roadside ditches, in sedge thickets along river banks, etc. The number of wintering in one place is different (from one to several hundred frogs, but most often two to three dozen winter). Males, females and juveniles hibernate together. Young frogs leave for winter 1-2 weeks later than adults. Hibernation lasts 155 days on average. Adults cannot stand hypothermia of the body below -0.4-0.8 ° C, underyearlings - 1-1.1 ° C, and maybe even lower. They are located: at the bottom of a reservoir, under overhanging banks, in thickets of vegetation, in flowing waters and under stones. The common frog prefers not very stony, fast-flowing, non-freezing rivers, peat ditches and swamps with thick silt. During the winter, the grass frog sits with its hind legs tucked in,and with the front, it seems to cover the head, turning them with the palms outward. Frogs hibernating in water can die due to freezing of water bodies to the bottom.

Reproduction

Reproduction takes place in puddles, reservoirs, lakes, canals, in any shallow body of water. Spawning begins 3-5 days after waking up. Males appear on reservoirs earlier, they sing mating songs inviting females. Mating begins on the way to the spawning pond. At this time, in females, all eggs have already ovulated and are in the last thin-walled, stretched part of the oviducts, ready for laying. Having washed out its eggs, the grass frog does not stay in the reservoir and disperses to summer habitats. During the breeding season, males on the hind legs increase the size of the swimming membranes on the hind legs. Masonry in the form of a lump formed due to the sticking of the mucous membranes of the facial membranes. One female lays 670-1400 small eggs.

Season / period of breeding

The breeding season is between April and early May.

Puberty

Maturation occurs at the age of 3 years.

Development

The rate of development depends on the temperature of the water. The higher the temperature, the faster development is (8-10 days). In deep, shaded reservoirs, caviar develops about four times slower than in well-warmed reservoirs. Caviar easily withstands low temperatures, but does not tolerate warm water.

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Offspring

The complete metamorphosis of the grass frog lasts 50-90 days. At higher temperatures, it occurs faster (21-26 ° C). After metamorphosis, growth continues for up to three years or more. The growth rate of tadpoles is up to 0.6 mm per day. Underyearlings are active during the day. They feed in shallow waters, among algae, on the vegetation film covering water bodies, and at their bottom. For the first 20-30 days, tadpoles keep close to each other. They scurry in different directions, but do not swim far, and the whole flock simultaneously moves in search of food and warm places in the reservoir. Tadpoles strongly oppress, and sometimes even lead to total death, of juvenile larvae of pond and sharp-faced frogs, reed and common toads. There is a high mortality rate during development. The mortality of eggs and tadpoles reaches 80.4-96.8%.

Benefit / harm to humans

The common frog eats a large number of insect pests. It is widely used in science (various studies, teaching students, etc.). In Europe, her paws are considered a delicacy.