by Andrei BAKIEV, Cand. Sc. (Biol.), senior research fellow, RAS Institute of Ecology of the Volga Basin, Togliatti, Russia; Andrei MALENYOV, head of the Herpetology and Toxicology Laboratory of the same research Institute

Black water snakes look like local species to people of Asia, but they are exotic to Russians. Now what are such snakes like, as found in Russia's European part?

FROM SUPERSTITION ON TO SCIENCE

Ordinary or common grass (Natrix natrix) and water snakes (Natrix) belong to nine ophidian families. Non-venomous, they pose no danger to man. They will live near water, and are good swimmers and divers. Black snakes ("melanists") often occur in populations of both species.

Snakes have attracted interest since time out of mind--of scientists and the common run alike. The worshiping of snakes (or ophiolatry*, from the Greek ophis, a snake) was common among tribes in what is now European Russia back in the Bronze Age (second millennium B.C.)**. There is archeological evidence on that in burial places of the Volga region and Caucasia. This cult could have possibly come from the East.

* Ophiolatry (ophiolatria, ophitism) was a widespread cult in all parts of the world with the exception of Australia. The branch of zoology dealing with ophidians (snakes, serpents) is known as ophiology--Ed.

** The Bronze Age, the second and late phase of the Epoch of Early Metal after the Copper Age and prior to the Iron Age.--Ed.

Ahmed Ibn-Fadlan noted this worship among the Bashkirs populating the middle reaches of the Volga*.

According to an old popular belief in Russia, there used to be a land of grass snakes ruled by a czar wearing a crown studded with gems. Should somebody kill a snake, the ophidian czar would wreak vengeance. Adam Elschläger (better known as Adam Olearius)** mentions water snakes in a note dated 27 August 1636--he says he saw such snakes near the town of Samara in the middle reaches of the Volga. In his Travel Notes Ivan Lepekhin***, a naturalist and linguist, wrote in his diary on the fourteenth of August 1768 he came upon an ordinary grass snake near the town of Kurmysh (today a village in the Pilninsk district of the Novgorod region.--Ed.). The scholar made comments on a local yarn about snakes as told by his companion.

The Military-Statistical Review of the Kazan Gubernia (Province), anno 1850, said this in part: "Some peasant households have grass snakes kept in izbas together with domestic animals." Popular beliefs that the souls of forefathers might get reincarnated in a pet snake were common among Slavs. The snake was a brownie, a household god and custodian that brought good luck

* Ahmed Ibn-Fadlan, an Arab traveler and author of the early 10th century A.D.--Ed.

** Adam Olearius (Elschläger of Gottorp. Schleswig, 1599-1671), a German traveler, savant and writer who traveled to Russia and Persia in 1633 to 1639.--Ed.

*** Dr. Ivan Lepekhin, junior scientific assistant of the Academy of Sciences, made a tour of different Russian provinces. His Travel Notes

appeared in four parts between 1771 and 1805.--Ed. and kept the wolf from the door. It was a sin to kill a snake in the shed or in the backyard, that would mean sure death to the master or mistress of the house. Should one do that inadvertently, he should throw away the stick that killed the snake--fling it into the water right away, or else the cattle and the fowl will be gone. If the family see a snake crawling away from the yard, this is a bad sign of poverty and other misfortunes. But if a snake crawls in, that's a good omen, for it will bring luck and affluence. If there is no snake at home--there must be something wrong in there.

BODY COLOR AND PROPAGATION AREAS

Ordinary, or common grass snakes (Natrix natrix) are remarkable for light spots on the head (yellow, orange, dusty-gray). Water snakes (Natrix) wear colors similar to those of the black viper but have no fangs (venom efferent teeth). They have a round pupil of the eye, the black viper has vertical. Many people mistake water snakes for poisonous crossbreeds of vipers and grass snakes.

The common grass snake is widespread in the southern and middle belts of European Russia, but its habitation area may go as far as the Arctic circle at Murmansk and beyond. The water snake is a warm-requiring ophidian, the northern boundary of its propagation lies in the Samara region (middle reaches of the Volga); the black color is predominant. It may be that melanism*

* Melanism (<Gr. melan, "black") relates to black-skinned species.--Ed.

carries out a heat-regulating function in the northern bounds of the habitation area, for dark ophidians absorb solar radiation better than light ones to get warm. The color of the skin is important in this respect.

Grass and water snakes are among the few ophidians that eat their prey live; they do not kill it by venom (they have none) and they do not strangle it as constrictors do by their coils. The former (grass snakes) are ranked among the batrachophages ("eaters of frogs", <Gr. bat-rachos, frog), that is they consume amphibians, while the latter (water snakes) are classed as ichthyophages ("fish eaters", <Gr. ichthys, fish). Yet the situation has been changing in these past few decades owing to the active immigration of the Pacific ratan goby (Perccottus glehni)* from the Far East. This fish species is increasingly present in the menu of the grass snake (in Mordovia, a republic in the middle reaches of the Volga, the ratan has become the number one food for the grass snake, which has changed from a batrachophage to an ichthyophage).

The species-specific makeup of the diet of the water snake living along the shores of the Volga and its tributaries is also changing. Today its prey includes Caspian and Black Sea gobies (Gobidae), namely Negobius cas-pius, and Negobius pontius. these fish species account for as much as half of the water snake's food rations.

Grass and water snakes that feed on vertebrates are in turn easy prey for many of them--from fish (pike, sheat-

* This fish species belongs to the Electridae family.--Ed.

fish, zander, pike-perch) to mammalians. In some cases large toads and frogs gobble small grass snakes. Such domestic fowls and animals as hens, cats, dogs and hogs pose a danger too. Mammals like the black kite, buzzard*, serpent eagle**, badger) are regular grass snake eaters, while most of the others eat grass snakes but occasionally.

Escaping for its dear life, a grass snake swims off or dives in if it is near a body of water, where it hides amidst water plants or buries itself in the silt. It may also hide in the high grass. While in water, a snake can stay under for many minutes without coming up. It makes use of the air in the lung for respiration (it has but one well-developed lung on the right side).

On dry land a grass snake lies low in shamming death if it is unable to escape, and stays motionless for a few minutes unless shooed. It is active in its defensive posture should someone make an approach. It coils up into a ball, hisses and makes passes at the aggressor like a viper does short of biting.

If captured, it is out to break away and ejects smelly excreta from the anus. The smell comes from the scent gland near the rectum. It may throw up the food from the stomach.

When captured, grass and water snakes are quite good at imitating death. They do it fine: belly up, tongue loll-

* Buzzard, a bird of prey looking like a kite but having shorter paws and tail.--Ed.

** Serpent eagle (Cireaetus) and short-toed eagle (Circaetus gallicus or Circaetusferox), a bird of prey of the Aquilidae family, Falco order).--Ed.

ing out--complete quiescence. Not so dusty! Some snakes puke drops of blood and mucus, if their forked tongue is swollen and there are numerous damages of small blood vessels. This sham death goes on for several minutes. Then the snake comes alive all of a sudden, resuming its usual posture and makes frantic efforts to beat it. A sham death like that causes an abrupt drop in the heart beat rate, or arrhythmia; the heart rate is back to normal once the show is over.

REPRODUCTION

They reach puberty at two or three years. They copulate in spring, in late April and early May, near their hibernation homes. During the rut season you come across groups of 25 to 30 snakes coiling into balls. Males always outnumber females. True, there is no sex discrepancy, the ratio of the sexes is close to parity. Yet the males are more aggressive, with large individuals pressing smaller rivals aside for the last favor, the coitus.

Grass snakes lay eggs in June in rotten wood, mold, humus or punk, that is where temperature is high enough due to putrefaction. Eggs do not survive in cold or in excessive humidity, on cold and rainy days when they are damaged by fungi.

The freshly laid eggs are always coated with oviduct secretion that, drying up, glues the shell to keep loss of moisture down. The eggshells are thinner at the sticking points to enable moisture exchange in laying beds. One female lays from several to dozens of eggs, it depends on her size--only large she-snakes lay the greatest number of eggs. Now and then several snakes lay eggs in one and the same place. For instance, as many as 1,200 grass snake eggs were found in the Vologda region near the village of Selishche in a glade under an old rotten door, 30x150 feet large. Lying over there was what remained of older, yesteryear layings.

People often take grass snake eggs for those laid by vipers, which is wrong: vipers bear their progeny live. Still and all, in many cases country folks and vacationers destroy "viperous eggs".

The incubation of eggs takes five or six weeks. The hatchlings do not pick food until after the first hibernation and subsist on the contents of the yolk (vitelline) sac*.

Grass and water snakes shed their skin (slough) in spring, summer and autumn. But fast-growing young or sick snakes do it of tener, six to eight times a year. Skin shedding takes about half an hour in healthy snakes. This is preceded by a dimming of the eyes for a few days, but the eyesight is back to normal. Grass snakes live in captivity for thirty years, while in the wild their life expectancy ranges between 15 and 20 years.

Grass and water snakes are common ophidians in most habitation areas. None the less in some places the common grass snake (Natrix natrix) is entered in the Red Book of endangered species (in Leningrad and Moscow regions, the City of Moscow) and the water snake (Natrix) is in the Red Books of the Republic of Bashkortostan, in the Lipetsk, Samara, Saratov and Ulyanovsk administrative regions. We rank them among black water snakes according to certain characteristics. Such snakes are endemic to this country.

* Part of the ovum nourishing the embryo up until the foetus develops organs of its own. The y.s. carries out other functions (immunoregulatory. metabolic, synthetic, etc.).--Ed.