Environmental Engineering Reference
In-Depth Information
monsoon season (July to October). The species
was indiscriminately killed for the purpose of
making luxury goods from its skin in late 1960s
and early 1970s. The level of poaching became
so severe that the population subsequently
declined, making the species endangered. The
initiation of crocodile breeding programme by
the Govt. of India in 1976 at Indian Sundarbans
reversed the situation.
Sea turtles are widely used by humans as food,
ornaments and leather. They are now endangered
and protected. Of the World
s 12 living families
and approximately 250 species of turtles, only 2
families are marine dwellers. They are Dermoch-
elyidae (common leatherback comprising of
sin-
gle
species) and Cheloniidae (comprising of
seven
species). These eight species have several com-
mon characteristics, including relatively non-
retractile extremities, extensively roofed skull
(Fig.
2.26
), limbs converted to paddle-like
'
ippers
with one or two claws and little independent
movements of the digits. All are large turtles;
adults weighing about 35
fl
Sea Turtles
Sea turtles are cold-blooded and lung-breathing
nekton belonging to class reptilian (Fig.
2.25
).
They appeared on the planet Earth millions of
years ago and got adapted to an aquatic life.
500 kg and exhibit
various adaptations to marine environment, such
as presence of large salt gland to excrete the excess
salt ingested with sea water and food.
-
Fig. 2.25
Views of sea
turtle species
