These Islands are blessed with a unique’ luxuriant evergreen tropical rainforest
canopy, sheltering a mixed germ plasm bank, comprising of Indian, Myanmarese,
Malaysian and endemic floral strain. So far, about 2200,varieties
of plants have been recorded out of which 200 are endemic and 1300 do
not occur in mainland India.

“The South Andaman forests have a profuse growth of epiphytic vegetation,
mostly ferns and orchids. The Middle Andamans harbours mostly
moist deciduous forests. North Andamans is characterised by the
wet evergreen type, with plenty of woody climbers. The north Nicobar
Islands (including Car Nicobar and Battimalv) are marked by the complete
absence of evergreen forests, while such forests form the dominant vegetation
in the central and southern islands of the Nicobar group. Grasslands
occur only in the Nicobars, and while deciduous forests are common in
the Andamans, they are almost absent in the Nicobars”. This atypical
forest coverage is made-up of twelve types namely

(1) Giant evergreen
forest (2) Andamans tropical evergreen forest (3) Southern hilltop tropical
evergreen forest (4) Cane brakes (5) Wet bamboo brakes (6) Andamans
semi-evergreen forest (7) Andamans moist deciduous forest (8) Andamans
secondary moist deciduous forest (9) Littoral forest (10) Mangrove forest
(11) Brackish water mixed forest (12) Submontane hill valley swamp forest.
The present forest coverage is claimed to be 86.2% of the total land
area.

TIMBER

Andaman Forest
is abound in plethora of timber species numbering 200 or more, out of
which about 30 varieties are considered to be commercial. Major commercial
timber species are Gurjan (Dipterocarpus spp.) and Padauk (Pterocarpus
dalbergioides). Ornamental wood such as (1) Marble Wood (Diospyros marmorata)
(2) Padauk (Pterocarpus dalbergioides), (3) Silver Grey (a special formation
of wood in white chuglam) (4) Chooi (Sageraea elliptical and (5) Kokko
(Albizzia lebbeck) are noted for their pronounced grain formation. Padauk
being steadier than teak is widely used for furniture making.

Burr and the
Buttress formation in Andaman Padauk are World famous for their exceptionally
unique charm and figuring. Largest piece of Buttress known from
Andaman was a dining table of 13′x 7′. The largest piece of Burr
was again a dining table to seat eight persons at a time. The holy Rudraksha
(Elaeocarps sphaericus) and aromatic Dhoop/Resin trees also occur here.

FAUNA

MAMMALS -
About 50 varieties of forest mammals are found to occur in A&N Islands,
most of them are understood to be brought in from outside and are now
considered endemic due to their prolonged insular adaptation. Rat is
the largest group having 26 species followed by 14 species of bat. Among
the larger mammals there are two endemic varieties of wild pig namely
Sus Scrofa andamanensis from Andaman and S.S.nicobaricus from Nicobar.
The spotted deer Axis axis, Barking deer and Sambar are found in Andaman
District. Interview island in Middle Andaman holds a fairly good stock
of feral elephants. These elephants were brought in for forest work
by a private contractor who subsequently left them loose.

Butterflies and Moths - With about 225 species, the A&N Islands house some of the larger and most spectacular butterflies of the world. Ten species are endemic to these Islands. Mount Harriet National Park is one of the richest areas of butterfly and moth diversity on these Islands.

Shells

Shells
are perhaps the most colourful and fascinating objects known to man
other than Gems since time immemorial. They served as money, ornaments,
musical instruments, drinking cups, in magic and in the making of fine
porcelains. They were also the symbols in rituals and religious observances,
and the returning pilgrims wore them as a token of divine pardon.

These islands
are traditionally known for their shell wealth specially Turbo,Trochus,
Murex and
Nautilus.
Earliest recorded commercial exploitation began during 1929. Shells
are important to these islands because some like Turbo, Trochus &
Nautilus etc. are being used as novelties supporting many cottage industries
producing a wide range of decorative items & ornaments. Shells such
as Giant clam, Green mussel and Oyster support edible shellfishery,
a few like Scallop, Clam and Cockle are burnt in kiln to produce edible
lime.

The Univalve
or one shell group belongs to the class Gastropoda having more than
80,000 species. Sacred Chank belongs to this group. Their body, in the
course of development, go through a complicated process, ‘torsion’ i.e.
the visceral mass is twisted though 90 degree together with the shell
that covers it. Under mysterious circumstances many a time this
process proceeds in the reverse direction thus creating an abnormal
shell which otherwise lives like a normal shell. A classic example
is the most wanted left-handed chank.

The Bivalve
or Pelecypoda has about 20,000 living species. Majority of then burrows
in sand or mud such as Pearl Oyster, Wing oyster, Giant clam etc.

A third group,
which is comparatively smaller, is called Cephalopoda, which includes
Octopus, Squid, Nautilus etc.

The
soft body animal, which lives inside the shell, is covered with a thick
layer of specialised epithelium cells known as rnantle, which in turn
secretes a two tier shell material making the shell. The outer layer
having a different colour pattern is organic in constitution, technically
called ‘periostracum’. Calcium ions from the environment are absorbed
into the blood and deposited evenly under this layer. The next inner
layer is called ‘nacre’ or ‘mother of pearl’ responsible for the pearly
lustre common to many shells

CORALS

Corals
belong to a large group of animals known as Coelenterata
(stinging animals) or Cnidaria
(thread animals). Corals grow slow, they have type wise site specific
growth rates. The massive forms may grow upto 2 cm. in diameter and
upto 1 cm in height a year, whereas, delicate branching forms grow between
5 to 10 cm. per annum.
A
true reef building stony coral may be unisexual or bisexual. They
breed together once in a year at a pre-determined time after dusk.
This process, at places is so intense that the water stays pinkish till
next morning. A large number of baby corals are released in the
open ocean this way. After sometime these baby corals settle over
a suitable substratum and start forming new colonies through asexual
reproduction. Their morphological features change with the environment
in which they settle. Due to this peculiar character they are often
called ‘Plastic animals’.

Stony
corals could be broadly divided into reef builders and non-reef builders,
the reef builders are called hermatypic
whereas others are known as ahermatypic corals. The reef builders
possess hard calcareous skeleton and need sunlight like plants to survive.
On the other hand, the non-reef builders are devoid of a true stony
framework and can live well without sunlight. A few among them are capable
of making protein based solidified skeleton.

FISHES

Each
life form in the sea is confined to its own particular zone, where pressure,
light, temperature and salinity are more or less constant. In
this stable environment some creatures have remained unchanged throughout
their entire history. The now famous Coelacanth,
one of the groups of fishes thought to have been extinct for 60 million
years, has remained essentially like its relatives as they appear in
fossils. Fishes are the masters of water world. For more
than 360 million years they have inhabited it. Today we have about 40,000 varieties of
fishes known to science. They range in size from 10 mm (Philippine
Gobie) to 21m. (whale shark). Some are flattened, others inflated,
many spindle shaped, a few snakelike, still others are compressed depending
on the environment in which they live or particular way of life.

MARINE
AQUARIUM

Marine fish and animal keeping still has a certain mystique attached to it. This is one of the most complicated aspects of live stock management.

The animal husbandry involved in it is mainly nurtured through water
chemistry and microbiology. The tropical coral reef inhabitants are
generally maintained in glass boxes known to us as marine aquariums.
These animals turn ‘fragile’ under captive atmosphere because the natural system to which they belong is so heterogeneous, complex and dynamic with every tide bringing in a different condition
that is so difficult to create artificially. However, since May l853
when the first tropical marine aquarium was made public in London, much has been understood and we are now able to practice a system where these animals are acclimatized and taught to be happy in their new environs.

Source -
National Informatics Centre, Port Blair.