Docent Informations
What does "docent" mean?
We are a young group. The pioneers started the group in April 1997. Since then, we have grown modestly to 93 docents. The Night Safari Volunteer Rangers were brought under the Docent Programme in March 1999.
The docents are self-run by a committee of docents which co-ordinates inputs from all docents and liaises with the zoo management to put into motion the group's activities.
A docent newsletter is issued every two months so docents can keep up with the latest in zoo happenings and docent activities. Sprinkled with inspiring stories and amusing anecdotes, the Docent Deliberations is always a great read! We also constantly undertake research projects to expand and update our knowledge as well as explore new areas of interest.
Singapore Zoological Gardens Docents
WHAT DO SNAKES EAT?

All snakes are predators! As a group, snakes eat the widest range of prey. Being slow, snakes tend to eat whatever is in abundance. One reason for their success is their ability to change their diet with the seasons, eating whatever is most plentiful. Others change their diet as they grow; eating small prey when they are young, and bigger prey as adults. Being "cold-blooded" they don't have to eat often and can survive in places with irregular supplies of prey.

 

Only a few snakes specialise in one type of prey. The only snake that has been seen to eat plants is the Tentacled Snake (Erpeton tentaculatus). It eats mainly fish but apparently sometimes eats aquatic plants. But snakes don't catch just any prey. Snakes make their calculations before catching prey. A big snake may pass over small prey which doesn't provide enough nutrition to offset the risk of catching it. Snakes may ignore prey too large or difficult to swallow whole.

 

Most snakes prefer to eat mammals: usually preying on the most abundant and easiest to catch mammals, mostly rodents. Their methods of killing (constriction and venom) works best on mammals. Snakes that eat non-mammals are usually too small or too slow to catch mammals. This suggests that the explosion in mammal diversity in the Tertiary Era may have led to the diversity in snakes.SOLE FOOD: Although snakes generally eat whatever is in abundance, there are some of the few fascinating specialists ...


Many snakes eat other snakes: Snakes are the ideal food for another snake as they fit easily and nicely inside the long body! The Kingsnake (Lampropeltis getulus) is the among the best known for this. It locates rattlesnakes at night by smell, then bites and coils around its prey, constricting it until the other snake is exhausted. The Kingsnake will then swallow it whole while still alive. The Kingsnake is resistant to the rattlesnake's venom. But Kingsnakes also eat other prey besides snakes. Surprisingly, the few snakes that eat only other snakes are harmless burrowing snakes which eat other smaller harmless burrowing snakes. The prey snake is killed by a twist of its spine. The King Cobra (right) is another snake that preys on snakes.

 

Snail specialists: The Brown Snake (Storeria dekayi) grabs the fleshy snail, wedges the shell under a rock, then rolls itself around to twist the titbit out of its shell. The Thirst Snake (Dipsas) holds the shell in its coils, wedges its long hooked lower jaw between the shell and the snail and uses its shorter upper jaw to slowly extract the snail. Because their prey is soft, the snake lacks expandable chins found on most snakes and it can't swallow large prey. The Southeast Asian Snail Eating Snakes (Pareatinae spp) has a lower jaw strengthened by the fusion of adjacent scales which is inserted into the snail shell. The snail is then hooked out with the long front teeth, and twisting movements. By removing the snail, the snake doesn't need to digest the shell and can eat more snails.

Other weird things that snakes eat:

 

Centipedes: the Cape Centipede Eater (Aparallactus)
Ants and termites: Blindsnakes (Ramphotyphlops)
Crabs: the White-bellied Mangrove Snake (Fordonia leucobalia). It stalks crabs at night on the mangrove mudflats, then captures the crab by jumping on them to pin them against the mud. It then bites into the crab to inject its venom. If the crab is too large, it will twist off and eat only the legs. This is probably the only snake that can disassemble its prey!


Toads which puff up in defence: The North American Hognose Snake (Heterodon) has enlarged sword-like rear teeth, first thought to puncture and deflate the toad, but now found to inject a venom to relax and deflate the toad.
Crayfish: the North American Queensnake (Reigina septemvittata) eats only freshly moulted soft-shelled crayfish.
Carrion, occasionally: Cottonmouth (Agkistrodon piscivorus)
Spiders and grasshoppers: Chinese Kukrisnake (Oligodon cinereus)
Skinks which are slippery due to their hard smooth scales: The Neck-banded Snake (Scaphiodontophis annulatus) of Central America and the African Wolf Snake (Lycophidion capense) have specialised front teeth on the upper and lower jaws which are elongated and modified to act like pincers to grip slippery armoured skinks and lizards securely by the head while they coil around the rest of the lizard.

Snakes eat the eggs of other creatures besides birds:
Reptile eggs are the only food of the desert dwelling Simoselaps which have two enlarged teeth on the side of its lower jaws which slit the leathery eggshell as it passes by. Like other egg specialists, its other teeth are greatly reduced. One snake feeds only on other snake's eggs (Cemophora coccinea).
Fish eggs: The Turtle Headed Seasnake (Emydocephalus annulatus) and Eydoux's Seasnake (Aipysurus eydouxi) eat only eggs of bottom-dwelling fish, sucking them up (together with a lot of sand) into their mouths. They have special lip scales which make their mouth rigid, and also have reduced teeth.

Frog's eggs are the only food of the South American Cat-eyed Snake (Leptodeira annulata) which seeks out the eggs of tree frogs among the trees!

 

Egg specialists: The African Egg-eating Snake (Dasypletis sacbra) eats freshly laid Weaver Bird eggs (it can tell and avoid eggs which have well-developed embryo, and eggs which have turned bad). It pushes its head over the egg, holding the egg in its coils and expanding its mouth to three times the size of its head. The Egg-eating Snake, instead of teeth, have a series of thick folds of gum tissue arranged in accordion-like pleats. These act as a suction cup on the smooth egg. Once in the gullet, it bends its neck sharply so the eggshell is pierced by the 25-30 modified internal spines on its backbone. Special muscles at the throat ensure none of the precious egg contents spill out as the egg is flattened by blunt ended vertebrates. Drained and flattened, the eggshell is later regurgitated whole. Other snakes which only occasionally eat eggs carry the unbroken egg in their bodies until the shell is digested. Only a few egg specialists spit up the shell. This allows them to consume more eggs, vital as they usually have no other food in-between egg-laying seasons. Being toothless, the Egg-eating Snake protects itself by mimicking dangerous vipers. Their egg-eating feat so seriously impressed humans that snakes have been portrayed in the myths of the Egyptians, Cambodians, Hopi and Mayans as swallowing the sun during eclipses, at nightfall and the winter solstice. Snakes have also been known to eat seemingly indigestible stuff like porcupines and turtles. For some reason, snakes don't eat millipedes although snakes can eat poisonous frogs.

 

Do snakes drink? Snakes need water especially before a moult and for making eggs. Snakes may drink from pools and streams as well as sucking dew and raindrops one by one through the tongue groove in the lip. Snakes that don't have access to freshwater, (desert and marine snakes) can get all their water from their prey. But the desert-dwelling Peringuey's Adder (Bitis peringueyi) flattens and lifts its neck to condense the coastal fog and drinks the resulting water droplets.

 

Snakes conserve water well so their need for water is minimal. They seek humid microclimates and don't urinate, excreting uric acid as a semisolid slurry with their faeces. They lose water mainly through breathing and through their skins. Although they don't have sweat glands, their skin is thin. Some desert snakes condition their skin with secretions from a nose gland to prevent water loss.


More about snakes


- What are snakes?
- Are snakes cold?
- Why are snakes long?

- What do snakes eat? Do they drink?
- How do snakes swallow?
- How do snakes hunt?
- Why and how do snakes kill?

 

Snake predators and how do snakes protect themselves?
Snake mating, eggs and babies

 

Where are snakes found?
Fascinating snake adaptations to various habitats

Snake bites and first aid

Snakes in danger: role and conservation and snakes in human culture

Snake records: biggest, smallest, deadliest and more

 

- More snakes
- More animals
- General snake links and references



Further informations in german can be found here!

Further Links
© Copyright SZGDOCENT. All Rights Reserved.