A sea snake bite is dangerous. It is often said that it can only bite people between the fingers or behind the ear, since its mouth is too small to grasp anything larger. This story stems from the fear of many new divers (perhaps some experienced ones too).

Will we find out if this is true or just a myth?

Most reptiles living in warm coastal waters are highly poisonous. The most common is the black and white one with the common name – Asia Minor sea snake. She is often seen swimming between reefs in search of prey.

They must breathe, so they can be observed on the surface.

Divers often say that aquatic reptiles are harmless to humans; their mouths are too small to bite. I was told that this is so. And I heard it again and again. I didn't question the theory until I saw real pearl farmers who were from this particular ribbon sea snake, which is said to be unable to bite.

However, they bite pearl farm workers and fishermen. They get entangled in fishing nets or hide in boxes where pearls grow. Feeling threatened when taken from the sea, they bite in self-defense. But – they can't bite people, right?

No, that's not right. The bite of a sea snake is very real, they can bite people. In order to swallow their prey, which can be more than twice the size of their neck, they must open their mouth wide. This obviously bites for defensive purposes. They pose a greater threat.

However, when normal conditions, the reptile never attacks a scuba diver, snorkeler or swimmer. The fangs of most species are not powerful enough to pierce a wetsuit.

Always treat sea creatures with respect. Don't put your hands inside the reef openings, don't touch the animals, stay away from mating animals, don't block their path to the surface to breathe, and you'll be fine.

Features of sea snakes

Most sea snakes reach sizes of about 1.2-1.4 meters. But in several species the length exceeds 2.5 m ( Hydrophis cyanocinctus) and even 2.75 m ( Hydrophis spiralis). Typically, females are noticeably larger than males. The weight of a snake depends on the species, sex and diet. Ringed Flattail ( Laticauda colubrina) with a body length of about 1.8 m, weighs about 0.9-1.3 kg (Voris et al. 1998).

Body shape also differs various types. For example, at Astrotia stokesii especially great attitude body thickness to length. Many types Hydrophis They have a particularly narrow head and neck, which is why it was previously mistakenly believed that they feed on thin fish like eels. It has now been established that they are capable of swallowing an animal twice the girth of the snake itself. A thin head is needed to detect prey in the narrowest crevices of the reefs.

The lifestyle of sea snakes is very different from land snakes. In this case, the first thing that is noticeable is the flattening of the tail from the sides, which is common to all sea snakes. In addition, they have a greatly reduced number of abdominal scales, except for the genus Laticauda, which move well on land, and which have salt glands under the tongue that secrete excess salt from the body. In sea snakes, the right lung is greatly enlarged and reaches the tail. In part, the lung serves as a hydrostatic organ, like the swim bladder in fish. When diving, the nasal openings are closed with special valves. Sea snakes are able to dive for up to two hours at depths of up to 180 m. It is assumed that this is facilitated by the absorption of oxygen from the water directly through the skin.

Sea snake venom

Sea snake venom is one of the most powerful snake venoms. Sea snakes feed on fish and cephalopods, and these animals are cold-blooded and more resistant to snake venom than mammals and birds. The poisonous teeth of sea snakes are fixed motionless (a primitive feature) in the front part of the upper jaw. They are slightly shorter than those of land snakes, but in most species they are long enough to bite through human skin. The exception is species that feed primarily on fish eggs.

The most poisonous sea snake is considered Aipysurus duboisii, which after the taipan and the brown snake is the third most poisonous snake in the world.

Photos

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See what “Sea snakes” are in other dictionaries:

SEA SNAKES, family poisonous snakes. Length up to 2.7 m. Over 50 species, in tropical coastal waters of Indian and Pacific Oceans. They don't go ashore. They feed on fish. The venom is several times more toxic than that of land snakes... Modern encyclopedia

A family of poisonous reptiles. Length up to 2 m. Over 50 species, in tropical coastal waters of the Indian and Pacific oceans. The venom of many species is more toxic than that of land snakes. They don't go ashore. They eat fish... Big encyclopedic Dictionary

- (Hydrophiidae), family of snakes. Dl. up to 2.75 m. The back of the body and tail are compressed laterally in a paddle-like manner. The head is covered with large shields and is small. The pupil is round. Valves in the nostrils prevent water from entering the nasal cavity. 16 births, approx... Biological encyclopedic dictionary

A family of poisonous reptiles. Length up to 2 m. Over 50 species, in the tropical coastal waters of the Indian and Pacific oceans. The venom of many species is more toxic than that of land snakes. They don't go ashore. They feed on fish. * * * SEA SNAKES… … encyclopedic Dictionary

sea ​​snakes- jūrų gyvatės statusas T sritis ekologija ir aplinkotyra apibrėžtis Gyvačių šeima (Hydrophiidae), kurią sudaro16 genčių, sea snakes 50 rūšių. Paplitusios Indijos ir Ramiojo vandenyno atogrąžų dalyje. Nuodingos, nuodai labai stipūs. Minta... ... Ekologijos terminų aiškinamasis žodynas

- (Hydrophidae) family of venomous snakes from the group of anterior grooved snakes (Proteroglypha s. Colubrina venenosa). The body is compressed laterally; the belly is keel-shaped at the back; the tail is short (no more than 1/6 of the entire length), compressed from the sides in the form of a high vertical... ... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron

- (Hydrophiidae) family of poisonous snakes. They live in the tropical waters of the Indian and Pacific Oceans. Body length up to 2.7 m. Well adapted to life in water: the body, especially its rear part, and the short tail are compressed laterally like an oar; ... Great Soviet Encyclopedia

A family of poisonous reptiles. Dl. up to 2 m. Over 50 species, tropical. coastal waters of the Indian and Pacific oceans. Poison in many species is superior in toxicity to the venoms of terrestrial snakes. They don't go ashore. They eat fish... Natural science. encyclopedic Dictionary

Sea snakes make up another family of venomous snakes. The swimming tail serves as such characteristic feature that sea serpents cannot in any way be mixed with others. On a superficial comparison, they seem more similar to... ...Animal life

The world's oceans are home to various creatures that can be very dangerous to humans. These include poisonous sea snakes, which are very aggressive. A striking representative of them is the poisonous sea snake Astrotia, which lives near Australia, Taiwan, Sri Lanka and Pakistan. It belongs to the family of swallowtails, has a bright color, from red to black, and a tail equipped with a fin. The length of the snake can reach 1.8 meters and 26 cm in diameter. Astrotia's body is covered with scales, which form a kind of keel in the abdominal part. The snake is perfectly adapted to life in water. It swims perfectly in both directions, can stay in the water without moving, maintaining buoyancy, dives to a depth of 30 meters, and can stay there for up to half an hour. A snake breathes only in water. She is not adapted to life on land.

Astrotia can be distinguished by its bright color and black alternating rings on its body. It has powerful, razor-sharp fangs that can easily bite through any wetsuit. The snake is very aggressive and attacks at the slightest danger. Its bite is poisonous. The poison is injected into the victim in small portions and kills him instantly. It is superior in strength and toxicity to cobra venom.
Astrocia live in whole clusters. IN mating season they gather together and form a wide ribbon, up to several kilometers long, hundreds of kilometers long. This ribbon slowly drifts along the surface of the ocean. The snake is viviparous. The offspring, from three to 12 snakes, are born directly in the water. Astrotia sheds every six months. It sinks to the bottom and rubs against the stones, thus freeing itself from the old skin. Frequent molting is due to the need to get rid of sea creatures stuck to the skin.

The snake feeds on fish and small marine life, which is found on the bottom and in coastal algae. To find them, she uses her senses of smell and touch, since her eyesight is not very good. The most favorite delicacy is eels, which the snake swallows whole. She does not disdain shrimps and crabs. Having had enough, Astrotia rests at the surface of the water.

The snake is very aggressive. If you swim to it at a distance of less than 10 meters, it will definitely attack and try to bite. Astrotia is especially dangerous during the mating season. Its venom is very toxic. It is a neurotoxin that affects nervous system and destroys muscle tissue. The first symptoms appear 5-6 minutes after the bite. This is a feeling of anxiety and malaise. Further worse - the body goes numb, heaviness appears in the heart area, and the larynx swells. The result is general paralysis and death.

I also wanted to write about sea snakes!
Namely - in the context of their danger and the possibility of their bites.

There are many rather mysterious discrepancies in various data on sea snakes (Hydrophiinae). For example: it is no secret that the venom of sea snakes is one of the most powerful poisons among all snakes; At the same time, divers are not only not taught to recognize and beware of them (I know from the examples of Thailand, Bali, the Philippines and Sri Lanka), they are simply calmly waved with their hands and even given to tourists to play with!
In addition, the consequences of registered sea snake bites are very different - from complete absence all sorts of symptoms or a trifling departure and to rapid death within a few minutes (a record for speed among all snakes!)...

Acalyptophis peronii

I understand that most of you are unlikely to ever encounter sea serpents. Because they are almost never kept in aquariums, and those of you who often walk along tropical coasts or like diving in Bali can hardly be included in the risk group.

But nonetheless! I’ll tell you a little secret, which for some reason is not disclosed on Wikipedia and other popular science sites - sea snakes kill people, around several dozen every year! Basically, these are stupid fishermen who get bitten by them when getting out of their nets.

Hydrophis sp.

What happens after a sea snake bite?
Their venom is characterized by an almost 100% neurotoxic effect, without any local effects - no pain, no inflammation, no swelling. It’s just that at some point a person’s muscles stop holding him together, he stops swallowing, speaking, breathing, and in those cases where death occurred within a few minutes, his heart simply stopped beating. Neurotoxins are powerful!
However, in most cases, the symptoms are either simply absent (as if there was a “dry” bite) or minimal (slight weakness, you want to lie around and not get up - similar to a hangover, only without the headache; sometimes you feel nauseous).
Such a variation in symptoms is difficult to explain by the usual percentage of “dry” bites (such as those from cobras or some vipers, without consequences).

Rather, the point here is directly in the structure of the jaws and teeth of these unusual snakes. Hydrophyins practically do not make blows or lunges, which we are used to seeing in snakes. Most of them hunt deep in the crevices of rocks and coral reefs, grabbing eels, other fish, and, less often, invertebrates that are buried there. In a typical case, the hunting of a sea snake is not a throw, but a calm crawl, sometimes even “groping,” and only then a capture. Apparently, this is why their teeth are short, poisonous fangs practically do not stand out in length from the rest and are located not only in the very front of the mouth, but somewhere in the middle)))
Obviously, this is about the same means of killing prey as the poisonous teeth of retrosulcated snakes - so that the victim stops kicking only at the beginning of swallowing.
The only exception is, perhaps, the open-oceanic species Pelamis platura - a two-colored bonito that preys primarily on free-swimming fish from pieces of algae and other debris floating near the surface. She makes real throws from an ambush - but she has long teeth, and in general her head is of a completely different shape than all the other “normal” sea snakes! Looks more like some kind of moray eel. But people (even fishermen) encounter it extremely rarely.

Laticauda laticaudata

And there are also very strange sea snakes that eat fish eggs, collect masonry from corals and algae - but their poisonous teeth are completely reduced, they poisonous bite in principle they cannot apply)))

Thus, in most cases of snake bites, snake venom either simply does not enter the body, or the skin is not completely pierced and the poison sits somewhere in the superficial layers of the epidermis, and some micrograms get inside, causing that very “rejection”. I don’t have a less clumsy explanation - for one milking, the vast majority of sea snake species receive such an amount of poison that can, with 100% probability, kill several healthy adult men! And in some species - several dozen... this is not some kind of efa, which, even with a full injection, may or may not kill; sea ​​snakes are something in the category of a black mamba or even a taipan.

Now a little about statistics. Almost all deaths(about 90%) are associated with one widespread species, Enhydrina schistosa - a funny sea snake with a stupid, but not very kind muzzle. According to Mark O'Shea, in one bite a snake spits out about 8-9 mg of venom, and for one person one and a half mg is more than enough. These snakes are very common along the northern coast of the Indian Ocean - Thailand, Burma, Bangladesh, India - just perfect an opportunity to meet people (there is already a clear abundance of them there)... Plus, they are considered one of the most aggressive sea snakes - if most hydrophyins behave somewhat passively when caught, then enhydrins strike in all directions and generally behave inappropriately .
Of other species of sea snakes, deaths are known from: Disteira major, Hydrophis caerulescens, Hydrophis gracilis, Hydrophis fasciatus, Hydrophis semperi (Philippine freshwater species! one confirmed death on Lake Luzon), Hydrophis spiralis, Lapemis hardwickii, Pelamis platura (only one confirmed case ), Thalassophis anomalus. These are species that are reliably identified - sea snakes are disgustingly identified, for most species it is necessary to describe the scales, look at the structure of the tail, and sometimes even count the number of maxillary teeth! So in reality, of course, the list of species is much longer.
In one small hospital on the east coast of Malaysia, serving nearby villages with a total population of approximately 10,000 people, in 1955 there were 30 cases of admission with sea snake bites, of which 4 resulted in death. Of course, this is less than all kinds of malaria, etc., and even less than the number of simply drowned people. But that's more deaths than from sharks! And everyone is afraid of sharks)))

It is unlikely that any of you will devote your life to working on an Indian fishing trawler. But still, handle these animals more carefully if you find one of them, say, on the shores of the South China Sea. There are cases (for some reason most in Vietnam) when people poked “dead” sea snakes washed up on the beach and got bitten.
And be careful when playing with them while diving - only if your hands are fully protected by neoprene.

Emydocephalus annulatus KREFFT, 1869

Sea snakes- representatives of ancient reptiles (reptiles), which, thanks to their secrecy, survived in the depths of water, where they live in crevices and irregularities of the bottom. They feed mainly on fish, which they come out to hunt closer to the surface.

Sea snakes feed on fish, but many species prefer sea eels. Moreover, as observations of swallowtails kept in aquariums have shown, some of them, when there is an abundance of various fish in the aquarium, prefer to starve if there are no conger eels among the fish.

Sea snakes are extremely poisonous animals. They have adapted to life in water according to natural conditions: the snake’s tail is flattened from the sides, their scales are located flush (at the same level), so these animals have a streamlined shape and easily swim in the water.

The most dangerous inhabitants depths of the sea - swallowtails. In total, there are 13 genera (39 species) of swallowtails, which is 3/4 of all sea snakes. The most poisonous of them bonito, olive snake, bicolor bonito and some others.

Sea snakes can be found in the tropical waters of the Pacific and Indian Oceans from the coast of Japan to Tasmania and New Zealand in the south, from the eastern coasts of Africa to the peninsula of California and Peru. Often these representatives water world found in significant concentrations, forming balls in depressions among the reefs. Living near the coasts, they try not to swim far into the sea. Apparently, the instinct of self-preservation is triggered, since fast current far from the shores it can take them into endless expanses, from which it is not so easy for them to get back out. However, some species of sea snakes swim far into the open sea, at a distance of up to 250 km or more from the coast, and there open waters ocean, easily floating on the water, hunting for fish. Sea snakes are often found at the mouths of rivers flowing into the sea, and sometimes even quite far from the sea, since snakes can rise up against the flow of the river. But they always return back to the sea!

All sea snakes are highly poisonous. Scientists have proven that the venom of some species of sea snakes is 50 times more effective stronger than poison king cobra- one of the most poisonous and largest snakes on land.

All types of sea snakes are divided into: flat-tailed and swallow-tailed. Flat-tailed animals still maintain a connection with land, but swallow-tailed ones do not. Scientists' opinions differ slightly regarding the number of species of sea snakes: some call 49, others - 52 species.

Sea snakes have a small head that is better able to cut through the surface of the water. The head smoothly transitions into the body, the length of which can be quite impressive. So, olive sea snakes can reach a length of more than 2 m.

The pupil of the eye of sea snakes, like that of cobras, is round, which is not typical for poisonous snakes. The eyes of sea snakes, like those of land snakes, are motionless due to the lack of eyelids. They have no sternum, no bladder, and no ear openings. Sea snakes' nostrils move upward to allow them to breathe without lifting their heads high out of the water. When a snake is immersed in water, its nostrils close with valves that prevent water from entering the lungs. The poisonous teeth of sea snakes, like those of land cobras, are small. On the sides of the head behind the eyes lie poison glands, one on each side. These glands are oval in shape with long ducts extending to the base of the poisonous teeth. Most sea snakes have two poisonous tooth from each side. The duct of the poisonous gland enters the opening of the tooth canal. Sea snakes are very diverse in body color. Many of them have a pattern on the upper side of the body in the form of transverse stripes, less often - in the form of longitudinal stripes or spots. The abdominal part has light colors, which is typical for almost all aquatic inhabitants. Fortunately, most sea snakes are not aggressive, but during the breeding season their character changes dramatically, they become aggressive, and the snake can easily bite when removed from the nets.

Sea snakes, despite their poisonous nature, are used as food. Sea snake dishes are prepared in Indonesia, where quite a lot of these animals live, and in the Philippines, from where sea snakes are exported to Japan, where they are considered a delicacy and are eaten fried or smoked.

Sea snakes, belonging to the subfamily of flat-tailed snakes, have not lost their connection with land: they can move quite well on land, sometimes crawling away from the water even at a distance of several kilometers. Lives in the Bay of Bengal in Australian waters ringed flattail. Not exceeding a meter in length, this snake involuntarily attracts attention with its beautiful body coloring: on the bluish-gray background of the back and sides there are darker transverse rings, the ventral side is painted calm yellow. The Ringed Flattail is non-aggressive and will usually bite if actively disturbed.

Sea snakes belonging to the subfamily of pinnipeds have forever lost contact with land, and there are much more species of them than flat-tailed snakes. All of them are very poisonous. There is only one species of swallowtail that lives in fresh waters - Luzon swallowtail, settled on the island of Luzon in the Philippine archipelago. Sea snakes swim easily, raising their heads slightly above the water and bending their bodies in waves. Very agile and fast in the water, once on land they become completely helpless and can even suffocate. Dovetails obtain food under water. As a rule, these are fish. Swallowtails hunt in the bottom zones of the seas, among stones, in rock crevices, and reef areas.

Scientists identify several types of commonly encountered and very dangerous sea snakes. These include common sea snake living in the waters Persian Gulf and in the waters of northern Australia; striped sea snake, also living in the waters of the Persian Gulf, in the waters of Japan and Indonesia; bengal sea snake, living in the Bay of Bengal, and finally, two-color bonito, widespread from the eastern coast of Africa to the Panama Canal. Two-color bonito is also called yellow-bellied sea snake for its unusual color: almost black back and bright yellow belly. The yellow-bellied sea snake has been seen even far from the shores in open ocean waters. There are especially many poisonous sea snakes off the coast of Indonesia.

Some species of sea snakes give birth to their young in the water. The cubs are very large, sometimes reaching half the length of the mother’s body. They immediately swim away to the sea and begin to lead independent life. The fertility of swallowtails is very low - from one to two cubs. Still, the number of sea snakes is high, especially in some tropical regions. Sometimes they gather in one place, and then the water is simply covered with snake bodies. Most often this happens during their breeding season. Some land-associated sea snake species are oviparous, but most are ovoviviparous.

When catching fish, sea snakes often get caught in the net. Although many consider them to be quite gentle, a sea snake caught in a net can bite a fisherman who carelessly removed it from the net and caused it pain. Sea snakes can also bite swimmers who unwittingly disturb them. For example, a hunting swallowtail does not like to be disturbed.