Snakes

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Snakes belong to reptiles.
Snakes are divided into:
• aglyph (without poison)
• back fanged (with poison in rear teeth) and
• fanged (with poison in fangs in the front of the jaw).
Aglyphs and back fanged are harmless to humans
and most of the big animals. Only the fanged snakes,
like vipers and cobras, are considered to be
dangerous, but only when disturbed. In Crete there
are no fanged species.
Are there venomous snakes in Greece
and which are they?
There are 23 different species of snakes in Greece
therefore Greece considered as the richest country
in variety of species in Europe.
Only seven species of snakes carry poison.
• Five snakes belonging to the family
Viperidae (vipers) have relatively strong
poison, while the other two of the family
Colubridae are back fanged and have weak
poison, harmless to humans.
• Vipers are never found all together in one
place. They are spread in different places all
around Greece. These are:
Viper - Vipera ammodytes
Ottoman viper - Montivipera xanthina
Milos Viper - Macrovipera schweizeri
Astritis - Vipera berus
Nanochentra - Vipera ursinii
• Venomous Colubridae are:
Montpellier snake - Malpolon insignitus
Cat Snake - Telescopus fallax
• No other reptile is venomous and they are all
absolutely harmless to humans
Hearing, Vision, Smell of Snakes
• Snakes do not have ears and we could therefore say that
they are deaf.
• Most snakes (except some with very good vision and
some other totally blind) do not see very well. They
perceive more shapes and movements, rather than the
details of the objects.
• The smell of snakes is excellent, but they do not smell
the way the mammals do. A special organ located in the
upper part of the oral cavity "organ of Jacobson», play a
significant role in their smell. They use their forked
tongue to collect volatile organic molecules which they
“place” at the “organ of Jacobson”. This organ processes
information, as the sensors of our nose do.
What do we believe for snakes?
• Snakes nowadays, are considered as “very bad”
animals, slimy, dangerous and symbols of evil.
Therefore most people hate them.
• In ancient times snakes were symbols of rebirth
and healing and were used in treating diseases,
from where comes the symbol of Asclepius kept
in Medicine today.
• Snakes are animals like any other. Snakes are
afraid of man and their first reaction is to get
away of him. Only out of fear will they attack
something that is not food for them.
Which is the role of snakes in the
ecosystem?
• Snakes play a significant role in the balance of the
ecosystem. In the first years of their life, they mainly
feed on insects consuming large quantities of them.
Later, after gaining the appropriate size, feed primarily
on rodents, thus becoming one of the main predators of
these, playing a crucial role in controlling populations.
• In its timelife one snake can consume up to 1000
rodents. Since rodents can easily propagate in large
numbers, we can imagine how much the rodent
population will be increased in an area, if one single
snake is killed.
Nose-horned Viper
Vipera ammodytes
You can see
Vipera ammodytes alive
in the Live Museum
of the Natural History Museum
of Crete
It is probably
the most
common viper
of Europe and
the most
common
venomous
snake of
Greece.
It may be found from sea
level to 2500m. It is
active during the day,
and sometimes also
during the night when
the weather
temperature is high.
It prefers sunny, dry and
rocky slopes with little
vegetation.
It often climbs on
bushes and dry-stone
walls. It breeds at the
end of May and females
give birth to 4-20
offspring at the end of
August. Hibernation
starts in October and
ends in February-March.
It is found in Greece mainland, Peloponnese, Evia,
Sporades, Ionian islands, Kyklades, Thasos and
Samothrace. It is absent from Crete and some small
islands.
The scales over the nose form a horn-like structure.
Superstitions attribute medical powers to this horn. Its
venom is dangerous for humans. When it is threatened,
it hisses loud and curls up into defensive position. It
preys upon small mammals, lizards, frogs and birds. Its
bite can be fatal to human if not treated.
Adder,
Vipera berus
Adder is a viper
species. It is
found in
mountains of
Varnountas,
Voras, Tzena, W.
Rodopi and in
Greek-Bulgarian
borders.
It reaches 65 cm in length. Females are bigger
than males. It is active mainly during the day.
Occurs at alpine areas, usually higher than
1600m above sea level.
Hibernation starts in
September- November
and ends in spring.
Females breed every
other year and give birth
to 3-18 offspring which
may mature at the age of
3 or 4. It feeds on small
mammals, small birds,
amphibian and lizards. Its
bite is poisonous not as
strong as Nose-horned
Viper's but still, medical
treatment is advised in
case of bite .
Leopard Snake
Zamenis situla
It is a harmless, non-venomous snake.
It is found in
Greece
mainland,
Peloponnese,
Evia, Crete,
Chios, Lesvos,
Samos, Kos,
Rhodes, in the
Ionian islands,
Skopelos,
Skyros,
Salamina,
Spetses, and
Kyklades.
It can be
found often
in human
habitats,
such as
gardens and
around
houses.
Mates late in the spring and females lay only 2-8 eggs
every other year.
It feeds mainly on rodents but also on lizards and small
birds. It may bite if caught.
Its
overall
length
reaches the 120cm.
It occurs up to 1600m
altitude and it can be
found in two forms:
striped and spotted. It
is a diurnal snake that
avoids high
temperatures.
It crawls carefully
among stones and
vegetation, and often
climbs on small bushes
and rocks.
Grass Snake
Natrix natrix
It is a harmless and non poisonous
snake.
It is found in Greece
mainland,
Peloponnese, Evia,
in the Ionian
islands, Thasos,
Samothrace,
Lemnos, Lesvos,
Chios, Samos, Leros,
Kos, Rhodes,
Karpathos, Skiros,
Kyklades and
possibly on other
islands too.
Its overall length is usually less than 1m. Females are larger
than males. It habits all kinds of wetland areas, but also
operates outside of water, often quite far away from it.
It variables in colours and patterning. It swims very skillfully
and fast. It feeds on amphibians, fish, rodents, reptiles,
invertebrates and sometimes even small birds.
If caught and
threatened, it secretes
a very smelly fluid and
often pretends to be
dead turning upside
down with its mouth
open with a
protruding tongue.
Mates in the spring.
The mating process can involve several males, forming a
pile around the female, claiming mating. The females,
depending on the size, can deposit from 2 to 100 eggs
(usually about 30) which hatch up to 2 months later.
Dwarf Snake
Eirenis modestus
It is a non-venomous, a very calm and
completely harmless snake.
It is found in
Lesvos, Chios,
Samos,
Samiopoula,
Fourni, Leros,
Kalymnos,
Symi, Kassos,
Karpathos,
Kastellorizo,
probably on
other
Dodecanese
islands too.
Its total length is up to 60cm, rarely more. Active mainly
at twilight but also at daytime at shady areas. It hides
under stones or in crevices, sometimes in small groups.
Small and quite slow snake that hunts actively its prey.
It feeds mainly on
arthropods, but
also on small
lizards. It breeds
early in the spring
and females give
birth to 3-8 eggs.
Hatchling snakes
are not longer
than 12cm. A very
calm snake and
completely
harmless.
Four-lined Snake
Elaphe quatuorlineata
skyrensis
A non venomous, harmless snake.
It is found in Peloponnese, Evia, Ionian islands,
Skiathos, Skyros, Kyklades and probably on other
islands too. Its total length reaches usually 150cm.
Young individuals have different coloration than
adults. It occurs in varied habitats, at altitudes up to
1400m. Diurnal snake that avoids high temperatures.
It hunts on the ground but often climbs on trees and
bushes. It swims capably. Feeds on small mammals
like mice, rats and small rabbits, also on birds, lizards,
amphibians and eggs. It breeds in spring and females
give birth to 3-18 eggs. Not a very aggressive snake,
but it could bite if caught. Usually a quite gentle
snake.
Balkan Whip Snake
Hierophis gemonensis
It is found in
Greece
mainland,
Peloponnese,
Evia, Ioanian
islands, some
islets of
Sporades,
Aegina, islets of
Argolikos Bay,
Kithira, Crete and
satelite islets.
It is a non-venomous snake with total length up to 100cm.
It occurs in varied
habitats at altitudes
from the sea level
up to 1400m.
Diurnal, fast and
very active snake.
It hunts usually on the ground but it also climbs on
bushes and small trees.
Feeds on small rodents, reptiles, small birds and big
invertebrates. It breeds in spring and females give birth to
3-10 eggs. It may bite if caught. Harmless snake.
Worm Snake
Typhlops vermicularis
It is a very small worm-like snake.
It is found in
Greece Mainland,
Peloponnese,
Evia, Thasos,
Lesvos, Samos,
Kos, Rhodes,
Skyros, Corfu,
Lefkada, Nydri,
Kyklades,
Salamina and
possibly on other
islands too.
Its head is barely distinguishable by two dark dots which
correspond to its eyes. Its atrophic eyes are covered with
scales. The scale at the end of its tail forms a hard pointy
tip, which it uses to cling and move. Females give birth of
4-8 eggs 11-25mm long.
It is a blind snake
evolved for living
underground. It
can rarely be seen
on the surface.
Hunts and lives
mainly in narrow
worm burrows or
it digs its own in
loose soil with its
hard, pointed tail
tip. It hunts
worms and
arthropods.
Milos viper
Macrovipera schweizeri
You can see
Macrovipera schweizeri alive
in the Living Museum
of the Natural History Museum of
Crete
It is a
highly
venomous
viper
endemic to
the Milos
island
group.
It feeds on
rodents, other
snakes and lizards.
Breeds in May and
lays 4 to 13 eggs.
Its total length is 80cm, sometimes more.
It variables in colouring.
It is mainly nocturnal at summer but diurnal at spring and
autumn. It occurs often at sunny combs with rocks and
bushes where it sets ambush for migrant birds.
It's the only oviparous viper in Greece and Europe.
Milos Viper is threatened mainly by degradation of its
habitat, by illegal animal collection and motorways. The
total animal population of the species is estimated to be
less than 10.000. It is strictly protected.
Its closest relatives
are found in North
Africa and the
Eastern
Mediterranean.
It is highly prized by
reptile collectors,
especially in its red
form.
Aesculapian Snake
Zamenis longissimus
It is non-venomous harmless snake.
Its overall length is up to 2m. It is found in sporadic
populations in mainland Greece, Peloponnese, Corfu
and Paxi.
In some areas it occurs up to 2000m altitude. It is a
diurnal snake that often climbs on bushes and trees
with skill.
It feeds mainly on rodents, but also on small birds
and lizards. Mates late in the spring and females lay
2-18 eggs that hatch about 2 months later. It may bite
if caught.
Asclepius Snake is associated with Asclepius, the
ancient god of medicine. The symbol of Asclepius rod
wrapped by a snake is being used even nowadays as
the symbol of medicine.
Cat Snake
Telescopus fallax
You can see
Telescopus fallax alive
in the Living Museum
of the Natural History Museum of
Crete
It is a back-fanged species
and is thus harmless to
humans, in contrast to
dangerous front-fanged
species, such as vipers or
cobras.
The venom
of the Cat
Snake is
used more
in the
digestion
process
than for
killing its
prey.
Females give birth to 5-9 eggs which hatch usually in
middle August. Usually hisses if handled and pretends
attacking but it will almost never bite.
It is found in Greece mainland, Peloponnese, Evia, Crete,
Lesvos, Chios, Rodos, Symi, Samos, Ikaria, Karpathos,
Kithitra, Antikithira, Kyklades, Kassos, Kalymnos,
Koufonissi, Ionian islands, Strofades, Egina, Agkistri,
Spetses and probably on other islands too.
Horned viper
Cerastes cerastes
You can see
Cerastes cerastes alive
in the Living Museum
of the Natural History Museum of
Crete
It is a highly
venomous sandwelling viper.
It is native to the
deserts of
Northern Africa
and parts of the
Middle East.
The Horned Viper ambushes its prey covering itself
with sand for camouflage.
It is primarily a nocturnal animal, feeding on small
mammals and lizards. It is characterized by two horns
over its head.
Egyptian Cobra
Naja haje
The Egyptian
Cobra, Naja haje,
is probably the
most
characteristic
snake species,
because of the
expansion of its
neck when
threatened.
It is It is absent
from Greece (It is
found in Africa
and the Arabian
Peninsula).
It is extremely poisonous and may reach 2.5 meters in
length. In ancient Egypt it decorated the Pharaoh’s crown
symbolizing power over life and death.

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