Python sebae
Description
With adults reaching lengths of over 6 m (20 ft), this is one of the world's largest species of snakes[2]. The typical adult length is 4.8 m (16 ft), but reports of specimens range to as large as the 9.72 m (32.1 ft) giant caught in Bingerville, Ivory Coast in 1932.[5]
The color pattern is typically brown, with olive and tan irregular blotching, fading to white on the underside. At a glance they can be easily mistaken for the Burmese python, P. m. bivittatus, but the two species are not closely related.
[edit] Geographic range
Found in Africa south of the Sahara from Senegal east to Ethiopia and Somalia, including Guinea-Bissau, Mali, Guinea, Sierra Leone, Liberia, Ivory Coast, Upper Volta, Ghana, Togo, Niger, Nigeria, Cameroon, Equatorial Guinea, Chad, Central African Republic, Democratic Republic of the Congo, Angola, Rwanda, Burundi, Sudan, Uganda, Kenya, Tanzania, Zambia, Malawi, Mozambique, Zimbabwe south to northern Namibia, Botswana and northeastern South Africa (to Natal). Extirpated from eastern Cape Province in 1927. The type locality given is "America" -- an obvious mistake. According to Loveridge (1936), no type locality was given. According to Stimson (1969) it was "Guiara, Brazil."[1]
[edit] Habitat
Typically associated with grassland and savannah habitat, not too far from water (rivers, streams, marshes), sometimes entering the edges of forests. Often occur in or near cane fields.[2]
[edit] Conservation status
While not considered endangered or threatened, this species is listed as a CITES Appendix II species, which puts restrictions on its exportation around the world. The primary reason for this is because their skin is used in the leather industry, frequently being made into shoes, belts, and purses.
[edit] Behavior
Highly dependent on sources of water, they estivate during the hottest and dryest parts of the year, remaining deep in burrows made by other animals. Noted for its bad temperament and readiness to bite if harassed. This is in contrast to the Burmese python, P. molurus, that is typically docile except when food is near.
[edit] Feeding
Opportunistic feeders, and will consume almost any animal they come across and can overpower by constriction. Young pythons eat primarily small rodents, which makes them popular with local farmers for reducing the populations of species harmful to crops, like the cane rat. However, adults are capable of taking very large prey, including young crocodiles, goats and gazelles, making them a potential danger to livestock.
[edit] Reproduction
Reproduction occurs in the spring with females laying as many as 100 eggs at a time. They guard their eggs aggressively while they incubate for 2-3 months. Hatchlings are between 45-60 cm (18-24 inches) in length and appear virtually identical to adults, except with more contrasting colors.
[edit] Captivity
This species is commonly the subject of captive breeding and is readily available in the exotic pet trade. They adapt well to captivity, feed willingly on commercially available rats and rabbits. However, their duller coloration and poor temperament generally makes their price lower than that of other python species, while their large size and voracious appetite makes them suitable only for the most experienced of large snake keepers.
[edit] Danger to humans
Attacks on humans are very uncommon. Although this species can easily kill an adult, there are only a few cases in which the victim, in most cases a child, was actually consumed. A Ugandan newspaper reported in 1951 that a 13-year-old boy was swallowed, but the python was forced to disgorge the body. In 1973 another newspaper reported that a Portuguese soldier was discovered in the stomach of a snake. In 1979 a 14.9 ft (4.5 m) python tried to eat a 13-year-old boy. It was discovered with the boy almost entirely swallowed, but after being hit by stones it regurgitated the body and retreated. The boy was 1.3 m tall and weighed 45 kg.[6] The last known case in which a person was eaten occurred in South Africa in 2002, the victim being a 10-years-old child.[7]
[edit] Subspecies
Subspecies[4] Taxon author[4] Common name[2] Geographic range
P. s. natalensis Smith, 1833 Natal rock python Type locality: "Port Natal," South Africa.
P. s. sebae (Gmelin, 1788) African rock python
Captivity
Hydrophis cyanocinctus
At best, these snakes make difficult captives. Ditmars (1933) described them as nervous and delicate captives that usually refuse to eat while preferring only to hide in the darkest corner of the tank.[6] Over fifty years later, Mehrtens (1987) wrote that while they were rarely displayed in western zoological parks, some species were regularly on display in Japanese aquariums. Available food supply is one factor that limits the number of species that can be kept in captivity, since some have diets that are too specialized. Another is that some species appear too intolerant to handling, or even being removed from the water. For any exhibit, the fish-eating species are the most logical choice. Regarding their facilities, the Laticauda species need to be able to exit the water somewhere and bask, while the other strictly aquatic genera do not, basically requiring only a tank of filtered (synthetic) sea water maintained at about 29°C, along with a submerged shelter. Species that have done relatively well in captivity include the ringed sea snake, Hydrophis cyanocinctus, which feed on fish and eels in particular. Pelamis platurus has done especially well in captivity, accepting small fish, including goldfish. However, care should be taken to house them in round or oval tanks, or in rectangular tanks with corners that are well-rounded, to prevent the snakes from damaging their snouts by swimming into the sides.[7]
Distribution and habitat
These snakes are mostly confined to the warm tropical waters of the Indian Ocean and the western Pacific Ocean, [4] with a few species found well out into Oceania.[11] The geographic range of one species, Pelamis platurus, is wider than that of any other reptile species, save for a few species of sea turtles.[1] It extends from the east coast of Africa, from Djibouti in the north to Cape Town in the south,[12] across the Indian Ocean, the Pacific, south as far as New Zealand,[11] all the way to the western coast of the Americas, where it occurs from northern Peru in the south (including the Galápagos Islands) to the Gulf of California in the north.[9] One source claims that Pelamis occurs as far north as Orange County, California in the United States.[13]
Sea snakes do not occur in the Atlantic Ocean, although Pelamis would doubtless be found there were it not for the cold currents off Namibia and western South America that keep them from crossing into the eastern South Atlantic, or south of 5° latitude along the South American west coast. Sea snakes do not occur in the Red Sea, possibly because of its increased salinity, so there is no danger of them crossing through the Suez Canal, and it is possibly also due to salinity, or rather a lack thereof, that Pelamis has not managed to cross into the Caribbean via the Panama Canal.[1] On the other hand, it has been speculated that Pelamis will enter the Atlantic if global warming eventually causes the aforementioned cold currents to become warm enough.[14]
Despite their marine adaptations, most species prefer shallow waters not far from land, around islands, especially waters that are somewhat sheltered, as well as near estuaries.[4][8] They may swim up rivers and have been reported as much as 160 km from the sea.[8] Others, such as Pelamis platurus, are pelagic and are found in drift lines; slicks of floating debris brought together by surface currents.[14] Some species inhabit mangrove swamps and similar brackish water habitats and there are even two landlocked fresh water forms: Hydrophis semperi occurs in Lake Taal in the Philippines, and Laticauda crockeri in Lake Te Nggano on Rennell Island in the Solomon Islands.[7]
[edit] Behavior
Much has been said regarding their temperament. Stidworthy (1974) describes all sea snake species as being reluctant to bite.[4] Fichter (1982) states that they are quite docile and even reluctant to bite.[5] Spawls and Branch (1994) claims that they are mainly docile and non-aggressive.[12][12] The U.S. Navy describes them as generally mild tempered, although there is variation among species and individuals.[11] Mehrtens (1987) suggests that species such as Pelamis platurus, that feed by simply gulping down their prey, are more likely to bite when provoked because they seem to use their venom more for defense. This is in contrast to others, such as Laticauda, that use their venom for prey immobilization; these snakes are frequently handled with impunity by local fishermen.[7] Species that have been reported as much more aggressive include Aipysurus laevis, Astrotia stokesii, Enhydrina schistosa and Hydrophis ornatus.[8]
Olive sea snake, Aipysurus laevis.
Ditmars (1933) mentions that when they are taken out of the water, their movements become very erratic. They crawl awkwardly in these situations and can become quite aggressive, striking wildly at anything that moves.[6] Yet, they are also frequently caught in nets by fishermen who unravel and throw them back barehanded, usually suffering no harm.[4] On land, sea snakes are not able to coil and strike like terrestrial snakes.[5]
It seems they are active both during the day and at night. In the morning, and sometimes late in the afternoon, they can be seen at the surface basking in the sunlight. When disturbed, they dive down below.[4] Sea snakes have been reported swimming at depths of over 90 m (295 ft).[5] They can remain submerged for as much as a few hours, possibly depending on temperature and degree of activity.[11]
Huge aggregations of sea snakes are occasionally reported. In 1932, millions of Astrotia stokesii, a relative of Pelamis, were seen from a steamer in the Strait of Malacca, off the coast of Malaysia, and formed a line of snakes 3 m (10 ft) wide and 100 km (62 mi) long.[14] The cause of this phenomenon is unknown, although it likely has something to do with reproduction.[1] Ditmars (1933) mentions that, in that same area, sea snakes can sometimes be seen swimming in schools of several dozen, and that after typhoons many dead specimens can be found on the beaches.[6]
[edit] Feeding
Most species prey on fish, especially eels.[8] The latter, when bitten, stiffen and die within seconds.[4] One species prefers molluscs and crustaceans,[8][7] such as prawns,[11] while a few others feed only on fish eggs, which is unusual for a venomous snake. Some reef dwelling species have small heads and thin necks, making it possible for them to extract small eels from the soft bottom that they hide in.[7] Stidworthy (1974) states that sea snakes will sometimes take bait from a fishing line.[4]
[edit] Reproduction
Except for a single genus, all sea snakes are ovoviviparous; the young are born alive in the water where they live out their entire life cycle.[7] In some species, the young are quite large: up to half as long as the mother.[5] The one exception is the genus Laticauda, which is oviparous; its five species all lay their eggs on land.[7]
[edit] Venom
Like their cousins in the Elapidae family, the majority of sea snakes are highly venomous, however when bites occur it is rare for much venom to be injected, so that envenomation symptoms usually seem non-existent or trivial.[8] For example, Pelamis platurus has more potent venom than any other terrestrial snake species in Costa Rica, but despite being abundant in the waters off its western coast, few human fatalities have been reported.[9] Nevertheless, all sea snakes should be handled with great caution.[8]
Bites in which envenomation does occur are usually painless and may not even be noticed when contact is made. Teeth may be left in the wound. There is usually little or no swelling involved and it is rare for any nearby lymph nodes to be affected. The most important symptoms are Rhabdomyolysis (rapid breakdown of skeletal muscle tissue) and paralysis. Early symptoms include headache, a thick-feeling tongue, thirst, sweating and vomiting. Symptoms that can occur after 30 minutes to several hours post bite include generalized aching, stiffness and tenderness of muscles all over the body. Passive stretching of the muscles is also painful, and trismus, which is similar to tetanus, is common. This is followed later on by symptoms typical of other elapid envenomations: a progressive flaccid paralysis, starting with ptosis and paralysis of voluntary muscles. Paralysis of muscles involved in swallowing and respiration can be fatal. 3-8 hours post bite, myoglobin as a result of muscle breakdown may start to show up in the blood plasma, can cause the urine to turn a dark reddish, brown or black color, and eventually lead to acute renal failure. 6-12 hours post bite, severe hyperkalemia, also the result of muscle breakdown, can lead to cardiac arrest.[15]
[edit] Taxonomy
Sea snakes were at first regarded as a unified and separate family, the Hydrophiidae, that later came to comprise two subfamilies: the Hydrophiinae, or true/aquatic sea snakes (now 16 genera with 57 species), and the more primitive Laticaudinae, or sea kraits (1 genus, Laticauda, with 5 species). Eventually, as it became clear just how closely related the sea snakes are to the elapids, the taxonomic situation became less well-defined. Some taxonomists responded by moving the sea snakes to the Elapidae, thereby creating the subfamilies Elapinae, Hydrophiinae and Laticaudinae, although the latter may be omitted if Laticauda is included in the Hydrophiinae. Unfortunately, no one has yet been able to convincingly work out the phylogenetic relationships between the various elapid subgroups, meaning that the situation is still unclear. Therefore, others opted to either continue to work with the older traditional arrangements, if only for practical reasons, or to lump all of the genera together in the Elapidae, with no taxonomic subdivisions, to reflect the work that remains to be done.[6][7][3][2]
Genus[2][3] Taxon author[2] Species[2] Subsp.*[2] Common name[3] Geographic range[3]
Acalyptophis Boulenger, 1869 1 0 Spiny-headed seasnake Gulf of Thailand, South China sea, the Strait of Taiwan, and the coasts of Guangdong, Indonesia, Philippines, New Guinea, New Caledonia, Australia (Northern Territory, Queensland, Western Australia)
Aipysurus Lacépède, 1804 7 1 Olive sea snakes Timor Sea, South China Sea, Gulf of Thailand, and coasts of Australia (North Territory, Queensland, West Australia), New Caledonia, Loyalty Islands, southern New Guinea, Indonesia, western Malaysia and Vietnam.
Astrotia Fischer, 1855 1 0 Stoke's sea snake Coastal areas from west India and Sri Lanka through Gulf of Thailand to China Sea, west Malaysia, Indonesia east to New Guinea, north and east coasts of Australia, Philippines
Emydocephalus Krefft, 1869 2 0 Turtlehead sea snakes The coasts of Timor (Indonesian sea), New Caledonia, Australia (North Territory, Queensland, West Australia), and in the Southeast Asian Sea along the coasts of China, Taiwan, Japan, and the Ryukyu Island.
Enhydrina Gray, 1849 2 0 Beaked sea snakes In the Persian Gulf (Oman, United Arab Emirates, etc.), south to the Seychelles and Madagascar,
SE Asian Sea (Pakistan, India, Bangladesh, Myanmar, Thailand, Vietnam), Australia (North Territory, Queensland), New Guinea and Papua New Guinea.
Ephalophis M.A. Smith, 1931 1 0 Grey's mudsnake North-western Australia
Hydrelaps Boulenger, 1896 1 0 Port Darwin mudsnake Northern Australia, southern New Guinea
Hydrophis Latreille In Sonnini & Latreille, 1801 34 3 Sea snakes Indoaustralian and Southeast Asian waters.[16]
Kerilia Gray, 1849 1 0 Jerdon's sea snake Southeast Asian waters.[16]
Kolpophis M.A. Smith, 1926 1 0 Bighead sea snake Indian Ocean.[16]
Lapemis Gray, 1835 1 1 Shaw's sea snake Persian Gulf to Indian Ocean, South China Sea, Indo-Australian archipelago and the western Pacific.[16]
Laticauda Laurenti, 1768 5 0 Sea kraits Southeast Asian and Indoaustralian waters.
Parahydrophis Burger & Natsuno, 1974 1 0 Northern mangrove sea snake Northern Australia, southern New Guinea
Parapistocalamus Roux, 1934 1 0 Hediger's snake Bougainville Island, Solomons
Pelamis Daudin, 1803 1 0 Yellow-bellied sea snake Indian and Pacific Oceans
Praescutata Wall, 1921 1 0 From the Persian Gulf to the Indian Ocean, the South Chinese Sea, and northeast to the coastal region of Fujian and Strait of Taiwan.
Thalassophis P. Schmidt, 1852 1 0 Anomalous sea snake South Chinese Sea (Malaysia, Gulf of Thailand), Indian Ocean (Sumatra, Java, Borneo)
The Grass Snake:
(Natrix natrix), sometimes called the Ringed Snake or Water Snake is a European non-venomous snake.
The Grass Snake is typically dark green or brown in colour with a characteristic yellow collar behind the head, which explains the alternative name ringed snake. The colour may also range from grey to black, with darker colours being more prevalent in colder regions, presumably owing to the thermal benefits of being dark in colour. The underside is lighter in colour. In Great Britain the Grass Snake is the largest reptile reaching up to 190 centimetres total length, though such large specimens are rare. Females are considerably larger than males, typically reaching a size of 90-110 cm when fully grown. Males are approximately 20 cm shorter and significantly smaller in girth.
They prey almost entirely on amphibians, especially the common toad and the common frog, although they may also occasionally eat mammals and fish. Captive snakes have been observed taking earthworms offered by hand, but dead prey items were never taken [1]. The bite is non-toxic and the snake is a hunt/ambush predator, consuming the prey live without using physical constriction. Grass Snakes are strong swimmers and may be found close to fresh water, although there is evidence that individual snakes often do not make use of water bodies throughout the entire season [2]. The preferred habitat appears to be open woodland and 'edge' habitat such as field margins and woodland borders as these may offer adequate refuge while still affording ample opportunity for basking activity and thermoregulation. Pond edges are also favoured and the relatively high chance of observing this secretive species in such areas may account for their perceived association with ponds and water.
Grass Snakes, as with most reptiles, are at the mercy of the thermal environment and need to overwinter in areas which are not subject to freezing. Thus they typically spend the winter underground where the temperature is relatively stable. As spring approaches, the males emerge first and spend much of the day basking in an effort to raise body temperature and thereby metabolism. This may be a tactic to maximise sperm production as the males mate with the females as soon as they emerge up to 2 weeks later in April or earlier if environmental temperatures are favourable. The leathery skinned eggs are laid in batches of 8–40 in June to July and hatch after about 10 weeks. As eggs require a temperature of at least 21° C and high humidity to survive and hatch, rotting vegetation, including compost heaps, are preferred locations. The young are about 18cm long when they hatch and are immediately independent.
After breeding in spring, snakes tend to hunt and may range widely during this time, moving several hundred metres in a day [3]. Prey items tend to be relatively large compared to the size of the snake and this impairs the movement ability of the snake. Snakes which have recently eaten rarely move any significant distance and will stay in one location, basking to optimize their body temperature until the prey item has been digested. Individual snakes may only need 2-3 significant prey items throughout an entire season.
Ecdysis also impacts upon the movement of grass snakes at least once during the active season. As the outer skin wears and the snake grows, the skin loosens from the body, including from the eyes, which may turn a milky white colour at this time. This presumably impacts upon the eyesight of the snake and they do not move or hunt during this time. The outer skin is eventually sloughed in one piece and normal movement activity is resumed.
video links
http://upload.wikimedia.org/wikipedia/commons/8/86/Ringelnattern3.OGG
Not being venomous, the snake's only defence is to produce a foul-smelling fluid (containing asafoetida) from the anal glands and/or feigning death by becoming completely limp[4]. Rarely, they may also perform fake attacks, striking without actually opening their mouths. They bite in defense rarely.
This snake is distributed throughout lowland areas of England and Wales but is almost absent from Scotland and not found in Ireland, which has no resident snakes. It is widely distributed in continental Europe, ranging from mid Scandinavia to southern Italy. It is also found in north-western Africa. British Grass Snakes belong to the subspecies N. n. helvetica, but experts differ on the number of subspecies.
The species has various predator species, including corvids, owls and perhaps other birds of prey, foxes and the domestic cat. In England, the species is scheduled under the Wildlife and Countryside Act 1981 and cannot be harmed or even handled without appropriate permissions.
Two of the subspecies are considered critically endangered: N. n. cetti (Sardinian Grass Snake) and N. n. schweizeri. In 2007, the Grass Snake was included on the updated UK Biodiversity Action Plan as a species in need of conservation and greater protection.
African Egg Eating Snake Information
Posted by bunty Labels: African Egg Eating Snake Health InformationAfrican Egg Eating Snake Information
Alternative Name : Boa Constrictor, Columbian Boa Constrictor, Common Boa Constrictor Scientific Name: Boa constrictor imperator
Common Food : In the wild, their diet includes prey such as rodents, birds, iguanas, and monkeys.
Origin : South America
Habitat : Living in hollow logs, and mammal burrows
The African Egg Eating Snake is a thin snake, and by maturity, the average individual will reach approximately 70 centimeters in length, though some may grow to over a meter in length. The basic coloration is gray to brown with darker square-like patches on the snake's dorsal surface that creates a zigzagging pattern. African Egg Eating Snakes have only rudimentary teeth in the mouth, greatly restricting their diet. There are 25 to 30 tooth-like structures at the back of the neck, which are really modified vertebrae. The Egg Eater is often confused with the Common Night adder in Southeastern Africa because of its rhombic markings. The similarity between these two snakes is a very effective defense mechanism as I have seen seasoned herpetologists who have mistaken the two and subsequently suffered the very painful bite of the night adder. Similarly, in the Southwestern region of Africa it is often confused with the Horned Adder. .
In captivity, African Egg Eating Snakes can usually be bred year round. However, in the wild, breeding occurs in the spring, and often, cooling snakes down to winter temperatures between 68 and 75 degrees Fahrenheit and lowering humidity can aid in encouraging breeding. Usually, African Egg Eating Snakes deposit between 6 and 25 eggs. They do not lay eggs in one location; rather, the clutch is usually scattered after a gestation period lasting between 80 and 90 days. Hatchling African Egg Eating Snakes can be fed finch eggs.
African Egg Eating Snakes have impressed people for centuries. In fact, in many mythologies, a serpent is said to swallow the sun at night, during eclipses, or during the winter solstice, before spitting out the disc once more. It is thought that this tradition could be based on the egg eating habits of snakes. Native to southern areas of Africa, the African Egg Eating Snake usually lives in grassy savannahs or wooded areas.
The African Egg Eating Snake, though not widespread in captivity, is a truly fascinating reptile. It is unique in its eating habits, and can make a rare and impressive pet.
Normally nocturnal, African Egg Eating Snakes usually spend days hiding in a sheltered area. Often a rock or log can provide a sheltered hiding spot. In the wild, most eggs eaten by African Egg Eating Snakes are laid by Weaver Birds. These snakes are adept at tree climbing, which is often important when the snake accesses birds' nests. Before consuming an egg, the African Egg Eating Snake will first test the egg with its tongue to ensure that it is not rotten. The snake then holds the egg in its constricting coils as it pushes its head over the egg. Amazingly, the African Egg Eating Snake can swallow eggs that are up to three times the size of its head. After swallowing the egg, pleated folds of gum tissue expand and contract to suck the egg further inside the snake. A series of tooth-like structures located at the back of the neck pierce the egg as the African Egg Eating Snake bends its head sharply. After the contents of the egg have been evacuated through these piercings, the eggshell will be regurgitated, flattened and emptied though whole. The defense of the African Egg Eating Snake includes coiling and straightening motions in rapid succession, rasping or hissing noises, and occasionally striking out. However, because they lack teeth, bites from African Egg Eating Snakes are largely harmless. Many African Egg Eating Snakes are said to be relatively docile, and do not often make threatening or defensive displays.
Poisonous personalities
Some reptiles are “venomous.” This means they are able to produce a poisonous fluid (venom) that can either be used for hunting or
defense. A reptile’s venom can paralyze
its prey - or break down its blood and
muscles, ready for eating.
Poisoning prey
Venomous snakes put
poison into the body
of their prey through
hollow, stabbing teeth
called fangs. The
venom overpowers
the victim and stops
it from fighting back.
Nasty spit
All cobras have fixed fangs at the
front of the mouth. Some use these
for spitting venom into the face of
their enemies - a defense strategy that can cause lots of pain,
and even blindness.
Spitting
black cobra
The stranglers
Some snakes - such as boas, pythons, and anacondas - capture and kill their prey
by wrapping themselves around the
animal until it can no longer
breathe. These snakes are
known as constrictors.
Burmese pythons can grow
up to 20 ft (6 m) long.
Friend or foe?
Some Burmese pythons
live close by humans. Tropical living
Often, they attack farm Most species of boa live in
animals - but their th reas of Central
feeding habits can a America. This
also help to control Cook’s tree boa is a large,
the number of rats, tree-dwelling snake
and other vermin, found only in the
in villages and cities. Caribbean islands.
The vines are alive!
Green tree snakes have light,
skinny bodies for creeping and
climbing. Their skin color helps
them to hide among green vines
and foliage as they hunt for birds
or tree-dwelling frogs and lizards.
The great pretender
The milksnake (right) is harmless,
but has the same set of colors
as the venomous coral snake
(above). Predators get
confused and so prefer
not to attack.
Reptile file
• A person can walk faster
than most snakes’ top speed.
• The mangrove ratsnake of Southeast Asia can catch bats as they fly out to feed.
• Egg-eating snakes crack
open their food using tooth-
like spines in their throats.
Later, they spit out the shell.
Without venom,
the milksnake
has to strangle
(constrict) its prey.
Rubbernecks
Many snakes eat hard-shelled birds’ eggs
or soft-shelled reptile eggs. The African
egg-eating snake only eats birds’ eggs. It
can unhook its jaws to swallow eggs that
are at least twice the size of its head.
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