Salt Water Crocodile

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Salt Water Crocodile Crocodylus porosus
By Riley Mathena
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• Crocodylus is derived from the Greek krokodeilos
  which means literally "pebble worm," referring to
  the appearance of a crocodile.
• porosus means "full of callosities", derived from
  porosis (Greek for "callosity") osus (Latin for
  "full of"), referring to the bumpy upper surface
  of the snout in large adults

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DISTRIBUTION Single individuals have been found
thousands of Kilometers away from their usual
range, due to their ability to travel long
distances by sea - barnacles have been found on
the scales of a few stray individuals. This
sea-faring ability probably helps to explain
their wide distribution.
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HABITAT

• As its name implies, this species has a high
  tolerance for salinity, being found in brackish
  water around coastal areas and in rivers.
  However, it is also present in freshwater rivers,
  billabongs and swamps. Movement between different
  habitats occurs between the dry and wet season,
  and as a result of social status - juveniles are
  raised in freshwater areas, but eventually are
  forced out of these areas (used for breeding by
  dominant, territorial adults), into more marginal
  and saline areas. Subordinate animals unable to
  establish a territory in a tidal river system are
  either killed or forced out into the sea where
  they move around the coast in search of another
  river system.

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APPEARANCE

• Adult males can reach sizes of up to 20 to 23
  feet the largest confirmed individual being
  20.7 feet.

• Females are smaller, the normal maximum adult
  size being 8 to 10 feet

• This is a large-headed species with a heavy set
  of jaws. A pair of ridges run from the eye orbits
  along the centre of the snout, becoming more
  distinct with age. The upper surface of the top
  jaw becomes very bumpy in large adult males.
  Scales on the flanks are more oval in shape than
  other species, although belly scales are
  rectangular, even and relatively small.

• The eyes, ears, and nostrils are located on the
  same plane on the top of the head, allowing for
  it to see, hear, and breathe while almost totally
  submerged. The eyes have a special second pair of
  eyelids known as the nictitating membrane. These
  eyelids are clear and protect the eyes while
  underwater. The ears, situated behind the eyes,
  have flaps which also close while underwater. The
  jaws are heavyset and contain 64-68 teeth. The
  teeth in the upper jaw are perfectly aligned with
  those in the lower jaw.

• Juveniles are normally pale tan in color with
  black stripes and spots on the body and tail.

• Mature adults are generally dark, with lighter
  tan or grey areas. The ventral surface (belly) is
  creamy yellow to white in color, except the tail
  which tends to be more grey on the underside
  nearer the tip. Dark bands and stripes are
  present on the lower flanks.

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DIET
Saltwater crocodiles take a wide variety of prey,
although juveniles are restricted to smaller
items such as insects, amphibians, crustaceans,
small reptiles and fish. The larger the animal
grows, the greater the variety of items that it
includes in the diet, although relatively small
prey still make up the majority of the diet even
in large adults. Prey items include crustaceans
(e.g. mudcrabs) and vertebrates (e.g. turtles,
goannas, snakes, shore and wading birds). Large
adults occasionally take much larger prey include
buffalo and domestic livestock, wild boar,
monkeys etc.
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BREEDING
Breeding territories are established in
freshwater areas. Females reach sexual maturity
at 10 to 12 years old. Males mature later, around
16 years old. 40 to 60 eggs are usually laid (can
range from 25 to 90) in mound nests made from
plant matter and mud. These are constructed
between the months of November and March during
the wet season - this serves to raise the eggs
above the ground to help prevent losses due to
flooding. Many nests are still flooded every
year, however, killing all the un-hatched
embryos. Alternately, if the nest is in danger of
getting too dry, the female has apparently been
observed to splash water onto it from a
purpose-dug, adjacent pool. Although the female
stays near the nest, some eggs do fall foul of
predators (e.g. monitor lizards, feral wild pigs
in Australia) and human egg collectors. Juveniles
hatch after around 90 days, although this varies
with nest temperature. The female digs her young
out of the nest when they start their
characteristic chirping sounds, assisting them to
the water by carrying them in her mouth.
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Many species of crocodilians are falsely viewed
as man-eaters, but fear of this species is not
unfounded, with a number of people injured or
killed each year, although in most cases these
tragedies can be avoided with increased
awareness. However, loss of life has led to a
degree of fear towards the species, making
conservation measures more difficult to
implement. Given its relatively wide
distribution, control of trade can be very
difficult. The commercial value of the hide is
very high (the most valuable of any crocodile
species), due to the lack of ventral osteoderms
which otherwise make tanning difficult, and the
size and shape of the belly scales. Unregulated
hunting mainly between 1945 and 1970 caused a
dramatic decline throughout the range of the
species. This has been controlled in some areas,
notably Australia, but threats from habitat
destruction still exist. Protection in some
countries is often ineffective, and while illegal
trade is relatively insignificant now for this
species, killing due to fear is becoming an
increasing problem.
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