06-bioresourcesstatu.. - M. S. Swaminathan Research Foundation

prawns, 29 species of crabs, 19 species of molluscs,
8 species of amphibians, 69 species of reptiles, 56
species of birds, more than 50 species of mammals
(Sanjeevaraj, 1999) and 88 species of fishes
(Ramadevi et ai, 2002)
From December to February about 10,000 to 15,000
flamingoes arrive at this place. 72 different species
totaling about 60,000 birds can be seen. Open bills
are the earliest to arrive. They come as scouts,
before rains hover over the lake or sanctuary
without alighting.
There are more than 32 species of Phyto and
Zooplanktons that are fed upon by diverse aquatic
animals. Plankton concentration is generally high
during post monsoon with a preponderance of
zooplanktons. The macro vegetation in the lake
consisted of rooted submerged plants such as
Halophylla ovalis and Zymodocea isoetifolia.
The highest density was (3250 nos/m') from the
southwest. The periphyton on the macrophytes
consisted chiefly of diatoms and varies from 5 to
2455 mm'. Bottom fauna consiste mostly of
polychaetes, tanaids, ambhipods, and mollusks.
Their concentration is more during monsoon and
post monsoon seasons, the pre-monsoon season
showing the lowest number. Based on the benthos
productivity the lake can be classified as
mesotrophic. (Raman et ai, 1975).
Out of three zones the southern zone was found to
be the most productive (average 1410/m2j followed
by the middle (average 1384/m2j and northern
average 1115/m2j zones. Molluscs and polychaetes
were responsible for the maximum production in
southern zone whereas in the middle zone,
amphipods mollusks and polychaetes formed the
important groups in order of abundance. In the
northern zone also amphipods were recorded in
maximum quantities followed by mollusks. (Raman
et ai, 1975).
iii. Threatened Species
Fish varieties like Sea bass, Milkfish and
Threadfins, prawns like Flower prawn and Tiger
prawn are threatened species in these areas.
Cardisoma carnifer (Herbst) a crab, Mud
Skippers like Periophthalmus sp and edible
oyster (Crasostrea madrasensis) which were
vulnerable to environmental changes prevalent at
Pulicat lake, are now also under threat.
iv. Conservation values
Pulicat Lake
Similarly sea turtles, rays and dog-faced snake
were also lost from the system (Sanjeeva Raj,
1998). However, some species like amphibians
which do not live in saline condition, are found in
the lake and also breeds like the frogs (Rana
crassipes) but at the same time some species
which are purely marine animals are also found in
the lake like Elephant Tusk Shell (Dentalium
octangulatum), Fish leech (Ozobranchus
branchiatus) lamp Shell (Glottidia sp.) etc.
Besides all these, a rare blood red, and totally
blind gobiid fish, which is unique to aquatic
ecosystem, Lepeophtherirus krishnai, a new
piscicolous copepod also found in the lake
(Kaliyamurthy, 1990). Clam beds, Oyster beds and
estuarine grass beds are some of the unique subsystem
with their associated fauna in the lake.
Among the local vegetation some plants usually
found at higher elevations on hills, are also
occurring especially in Sriharikotta island. They
are: Ampelocissus tomentosus, Chloroxylon
swietenia, Lepisanthes tetraphylla, Opilia
amentacea, Pamburus mission is, Polyalthia
korintii, Pterospermum canescens,
Pyrenacantha volubilis, Strychnos potatorum,
Suregada angustifolia, Thespesia lampas,
Trema orientalis, Ventilago denticulate
etc.(Suryanarayana and Rao, 2002)
As winter sets in, migrant water birds from distant
northern lands have been arriving at their
ancestral breeding sites in south India. Most such
sites have been traditionally protected by local
peasants who look forward to the arrival of these
birds to their village as deities that bring good
luck to their paddy crops. Ironically, what these
migrant birds give back to the farmers in turn is
their excreta (guano), which dissolves in water
and supplies nutrients to paddy fields.
In Pulicat Bird sanctuary a variety of birds have
kaleidoscopic feeding association. Nelapattu Bird
Sanctuary, a breeding sanctuary for birds is about
95 kID north of Chennai and about 80 km south of
Nellore, on national highways (NH 5). This
sanctuary invites numerous birds to nest and
breed on Indian Oak (Barringtonia acutangula)
trees. Birds that arrive late in the season take
shelter on the babul trees, (Acacia nilotica)
growing on the edges of the sanctuary. It is
interesting to watch birds nesting pattern,
breeding behavior, feeding habits and protection of
Around 10 to 12 fish species, found to be common nestlings at this sanctuary located at Vedurupattu
20 years ago in the lake are lost from the system. village 91 km from Chennai on NH 5. At this place
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