Plantations form second line of defence Pondlcherry. Sand-binding trailers like in beach protection. Very effective in Iipomoea pes-caprae, Spinifex squarTOsus,. controlling wind-erosion, plants cannot put a Cyperus arenariwn are part of our natural h alt to sea-erosion If It is in a very s evere biodiversity. form. However , their role cannot be underestimated. They serve as wind brakes , For greening the salty marshlands check the m ovement of beach sand and (Kharlands) mangrove species are of great prevent the entry of s alt spray into the fertile value. Salvadora persica has the added areas of the interior. advantage of Its seeds being used In soap industry. The plantations besides proViding Casuarlna equlsetifolia is the key green cover to combat salinity also proVide species. Other litteral species of significance income for the rural poor. in coastal afforestation programmes are Baningtonia asiatica, TerminaLia. catapa, Thespesia populnea, CaLophyllum inophyllum, V.M. MEHER-HOMJI Pongamia. pinnata, Hyphaene indica a French Institut decorative branch ed s pecies of palm cominon Pondichery - 605 001 in Diu and Daman and Cocoloba uvifera of

KRUSADAI ISLAND : THE BIOLOGIST'S PARADISE

INTRODUCTION: The morphometric features of this island with thick algal seaweeds, mangroves, The name KIusadai may symbolically seagrasses , coral reefs, fringing reefs, patch m ean Lord Shiva with m atted locks - as a reefs, shingles, cay etc., may be said to manifestation of Lord Dakshlnamurtl. The resemble, in abird's eyeV!ew, the matted­ exact m eaning of the word Krusadai Is locks of Lord Dakshlnamurtl. Hence the difficult to fathom . 'Kru' (as a corrupt form island m ay have been so named. Nearby, of 'Kuru' may also m ean sh ort or abridged) Krusadal is the island of meaning is perhaps wrongly s pelt for Guru m eaning snake or. serpent which Is also Lord Shiva Teacher or Mentor. (in Tamil,in both ways wears around His neck and upon which 'Kru' or 'Guru', it could be written). Lord Vishnu reclines. Assuming its Tamil version of the word 'Kni' to mean Guru = i.e., 'Mentor' or Nestor - and The island, since time immemorial, 'Sad ai' meaning m atted locks, we can belonged to the Raja of Rarnnad known by visualise the picture of Lord Dakshlnamurtl. the title '' (Sethu for In Its serene atmosphere, the place is Rameswaraml. who sold it to then British veritably' an eternal abode for silent (Indian) Government of the Presidency of m editation. Lord Dakshlnamurtl is Madras for less than Rs.6,OOO/- in 1914, known to teach and dispel ali doubts largely through the efforts of James Hornell. of 'sishayas' or diSCiples by transmitting Thus, the erstwhile Madras PreSidency got the lessons of discourses and answers and its foothold here; and, s o the Fisheries replies to doubts raised ''through thought Department founded here in 1914 or so, waves" In eloquent s ilence and in eternal established Its token presence, although on bliss, when and where speech b ecomes a . small scale, yet vibrant in activities, superfluous! recognizing its unique potential and rich diversity of life forms. But the scientific

SeshaiyaJla VoL 4 No.1 1996 63 studies in the area of the During the last five decades or so, date back to 1880 or even before (Carter, the old Marine BiolOgical Station has 1880, Foote, 1888). remained closed and the James Hornell Museum and the laboratories (Fig. 9, 11) The finding of KIusadai is rather stand as mute testimony to their hoary past. difficult on an ordinary map of even The other two buildings KIusadai BiolOgical peninsular India. KIusadai island is Station (Fig. 6) and the Rest house (Fig. 10) situated in the Gulf of Mannar (lat. 9° 14'N which were constructed later, seem to be and long. 7go13'E) near the well-known maintained in relatively good condition. Due tourist places of pilgrimage of to lack of interest in its adequate and Dhanuskodi in Ramanathapuram maintenance most of the old structures are district of Tam1l Nadu. The distance to the now in disrepair and in dilapidated island from Mandapam on the mainland Is 6 condition, no doubt giving refuge to garden km and from Pamban island Is 4 km. This lizards (Calotes versicolar and Hemidactylus Pamban island has a length of 2050 metres frenatus), snakes (Dendrophis pictus and and width of 700 metres and is spread over Dendrelaphis tristis), scropions, antipeds, an area of 67 hectares. The coral reefs millipeds, scutigera and spiders. Restoring around the island and the shallow the Marine Biological Station to its prestine lagoon-like portion between the reef and the glory is the urgent need of the hour. shore would form excellent sites for collection of various kinds of nora and SOUTHEAST COAST OF KRUSADAI : fauna. The noteworthy feature of the island On the southeast side of the KIusadai is its easy accessibility to a unique number island Is the famous coral reef called of flora and fauna inclusive of the living Galaxea reef (Fig. 4). It would get exposed at coral reefs in natural conditions. KIusadai low tides. The corals belonging to the genus island has, thus, become the "BiolOgists GaLaxea have largely contributed to its Paradise" and attracts a never-ending formation lending the name to this reef. The stream of students, ·teachers and eminent reef itself is composed of dead coral rocks scientists from India and abroad from about with full of holes. In lllany places the reef is 1898 of recorded history. highly vulnerable and it is risky to tread on it as It can collapse beneath one's own KRUSADAI MARiNE BIOLOGICAL STATION weight. Once inside the reef, the bottom Is The rich biological diversity prompted sandy with an admixture of mud In places. Mr. James Hornell, the then Director of This reef which is covered with seaweeds Fisheries Departm"nt of the Government of slopes steeply Into the sea. During the low erstwhile Madras PreSidency in the year tide, the water is quite clear and many 1914 to recommend the establishment of a interesting algae can be conveniently Marine BiolOgical Station on the KIusadai observed and studied in thetr In their own island. The station was established in 1914 niches. As mentioned earlier, the outer or so, with no modem amenities like potable portion of the reef is exposed to the surf water, electricity, etc. Besides founding the during low tide, but during high tide the station, a pearl oyster farm and later a waves just roll over and the algae on the fish-farm were also established. The station reefs are then exposed. The southeast end of had a museum (later came to be known as island is sandy and Is called as 'Sand Point'. James Hornell Museum), a library, two (Fig. 1) . .1aboratOlies (Figs. 7, 8) an aquarium and a photographic room, in addition to store The coral reefs on the western part of rooms and quarters for the staff. the Ga1.axea reef give shelter to an interesting and varied potpouri of marine

64 Seshaiyana Vol4 No.1 1996 animals. The corals both live and dead, .milk fish ehanos chanos are found in large provide shelter and lebensraum to a variety numbers in the Watchman's Bay. From this of sponges, coelenterates, planartans, point onward the shore line is densely polychaetes, crustaceans, polyzoans, covered with mangrove vegetation. The sea mQlluscs, tunicates etc. On the Western end front sides of the vegetation are very muddy. of fue island is the Prochordate ptychodera If one attempts to tread on the soil where area where two genera of Enteropneusta the mud, the mud Is thin and fine, the he (ptychodera and Chlamydothoraxj. may go easily down upto his knees. At this Polychaete worms occur abundantly along spot, the poisonous snakes (Hydrophis sp. with sea-cucumbers, HolothwiD. atra and H. and Enhydrina sp.) also would climb up the scabra the former occurs more abundantly. ashore at nights and stretch themselves among the roots of the mangrove trees. The NORTHERN COAST OF KRUSADAI : Western part of the northern shore is very The Kundugal channel along the muddy and hence is known as 'Bushy Point'. northern shore of Krusadai island is an ideal LAND FLORA AND FAUNA OF THE place for tow net collections. There flows a ISLAND: strong current from the Gulf of Mannar to the and vice versa. It is an 'lbe island has cultivated coconut, enchanting place where dolphins could be palmyrah and casuarina groves. Creepers seen in large.numbers swimming and diving. like Ipomea bilDba, Spinifex squarrosus and Launea pinnatijldn. and climbers like Vites On the Western side of the pier (Fig. I), negundo and GloriDsa superba grow anemones, large star fishes and small sea abundantly on the northern side of the urchins are found. The pearl oyster (Pinctada island. Large trees like margosa (neem), fucata) farm is in the neighbourhood. One banyan and gooseberry are seen in the joint sector company known as eastern part of the island. Shrubs of Pearls' is engaged in commercial 'Pearl Dodonea viscosa, Indigofera oblongifoUa and culture' venh!re here in collaboration with Scaevola frutescens form dense patches all the Tamil Nadu State Fisheries Department. over the island (Fig. 12). Grasses like The nucleus along with the mantle is Cymbopogen caesius and Fimbristylis Implanted into the pearl oysters (Pinctada spathacea are found over the sandly tracts. j'ucata) at Mandapam laboratory and are cultured by suspending them in the rafts The fauna on land is represented by near Krusadai island. beetles, butterflies, moths, dragon-flies, red-cotton bugs, ants, termites, snakes, Further west, in the Porites Bay (Fig. I), lizards, scorpions, centipeds and spiders. the bottom is muddy. The Bay is inhabited The following birds reside permanently on by In;nnense masses of the corals Porites sp. the island: the spotted owlet, the houee and and Acropora sp. Large' masses of the coral jungle crows; the king crows, the skylark, Favia abdiata are also common along with the sun bird, the myna and the grey representatives of about twenty other species paritidge. The black rat Ratius rufescenes of corals. To the west of Porites Bay, the and the white rat Tatera cuvieri are the shore again curves inwards forming 'another mammals of the island. large bay. The Watchman's Bay with the muddy bottom which almost completely gets REMARKS AND SUGGESTIONS: . exposed at low tide. The mud flat is strewn The Krusadai island is under the with Cerithidea cingulata. Worms especially control of Tamil Nadu State Fisheries terebellids are abundant in the mud and Department. The office of the Research heimJ.t crabs on its surface. lbe seeds of Assistant of the Fisheries Deparitnent in the

. \ . , Seshaiyana Vot.4 No.1 1996 - 65 Kundugol Channel N oyster farm Coral RHf ...... _ .. ~ "" "" , '. , .. ". Watchman. ~ Boy "'-~• Sand YPoint "', .' ";:Galox.., Reef

w.. t Bay t*y.Cho~ra . Ateoi BUShy

GULF OF MANNAR

- Fie. 1. KRUSADAI ISLAND then (Chacko. 1955)

Kundugol Channel N :!l. Pearl oyster farm Coral RHf · ~ ,r;n ..... ,f..... , , Porit.. Boy , , Watchman • . Boy

w.. t Bay Bushy Point

GULF OF MANNAR

Fig. 2 . KRUSADAI ISLAND now

Q6 Seshaiyrina Vol4No.11996 LEGENT TO FIGURES (Krusadai Island : The Biologist's paradise by k. Jeyabaskaran and P.S. Lyla)

Fig. 1. Map showing the Krusadai Island then (Chacko, 1955)

Fig. 2. Map showing the Krusadai island now

Fig. 3. Krusadai Marine Biological Station Adntinistrative Office, Mandapam

Fig. 4. Galaxea Reef, Southeastern side of Krusadai island

Fig. 5. Damaged building, built by corals

Fig. 6. Marine Biological Station, Field Research Laboratory, Krusadai island

Fig. 7. Marine Biological Laboratory, Krusadai island

Fig. 8. Marine Biological Laboratory, Krusadai island

Fig. 9. James Hornell Museum, Krusadai island

Fig. 10. Rest House for students and scientists, Krusadai island.

Fig. 11. James Hornell Museum and Laboratory, Krusadai island

Fig. 12. Thick scrubby and coastal vegetation on Krusadili island

Fig. 13. Sea erosion of southeast coast of Krusadai Island

LEGENT TO FIGURES (The impact of chemicals used in aquactultme upon the environment by M. Srinivasan et al.) Page No. 72

I. A successful harvers of Penaeus monodon by using ess=tial chemicals llke zeolite, lime, etc.

Ii. Penaeus monodon affected by protozoan disease (Zoothamnium)

LEGENT TO FIGURE [Manakudy (Kanyakumarl) mangroves by G. SanthakumarJ Page No. 188

!. Lushy growth of mangroves with the author in the foreground

Seshaiyana Vot.4 No.1 1996 67 FIG. 3 FIG. 4

FIG.4 FIG. 4

68 FIG. 5 FIG. 6

FIG. 7 FIG. 8

69 FIG. 9 FIG. 10

FIG. 11 FIG. 12

70 FIG. 12 FIG. 13

FIG. (i) FIG. (ii)

FIG. (i)

71 area is located at Mandapam, on the Mannar : Porifera. Bull. Madras Govt. Mus. mainland opposite the Krusadai Island who Nat. rUst. Ser., pp. 30. regulates the visit of the college parties and Carter, H.J., 1880. Report on specimens others to the island. The visiting parties dredged up from the Gulf of Mannar. Ann. should wrtte directly to the Research Mag. nat. Hist., 5 : 437-457 Assistant, Krusadai Marine BiolOgical Station, Mandapam - 623 520, Ramnad Chacko, P.T., S. Malladevatl atld R GaneSatl, District, Tamil Nadu, for permission to visit 1955. A guide to the field study of the fauna the island and for boat facilities to ferry and flora of Krusadai Island, Gulf of across. The department also supervises the Mannar. Contrib. Mar. BioI. Stn. field work of the visiting parties to the Krusadai Islatld, Gulf of Mannar. 3: 10 - 16. island. This way, the fishertes depattment in all its earnestness tries to prevent Foote, R (Bruce) 1888. Notes on judiciously vandalism and over exploitation Rameswaram Islatld - l. Madras Christian of the resources. TI,e visitors, especially the College Magazine: 828-840. college parties who come in large numbers Gravely, F.H., 1927. 'The littoral fauna of here every year, cause often irreparable Krusadai island in Gulf of Mannar. Bull. damage to the animal life. In their Madras. Govt. Museum (N.S). N.H. Section youthful enthustasm, the students collect VoLl No.1. ppl-179. more specimens and discard them after the tours. This should be avoided at any cost. Iyengar, M.O.P., 1927. Krusadai islatld flora. The teachers accompatlying the students Bull. Madras Govt. Mus. N.S., 1 : 185-188. should instruct them to observe the animals La! Mohatl, RS., 1986. The Krusadai islatld, in their natural habitat, to study the Souvenir, Published on the occasion of 35th ,; behaviour of the animals atld to understatld Anniversruy of the Recreation club of the beauty and sophistication they have C.M.F.RT., Matldapam Camp. achieved in the natural habitats. This will go a long way in preserving the rich marine life Mathai, G., 1924. On a species of subfossU of the island. The flshertes department must solitruy corals from the Chilka Lake. Mem. also check the illegal collection of seaweeds lndiatl Mus., 5 : 999-1003. from the islatld which is done through The Gulf of Mannar Biosphere Reserve. operation of small boats as it leads to reef Project Document No.5, 1987. Govelnrnent of damage. 1bis "Biologist's paradise" with its lndia, Ministry of Environment & Forests, rich and varied life forms should be New Delhi, pp. 105. preserved at aD costs for postertty. Every effort should be taken in this direction.

REFERENCES: R. JEYABASKARAN AND P.S. LYLA Burton, M., 1937. Supplement to the littoral CAS in Marine Biology fauna of Krusadai island in the Gulf of Parangipettai - 608 502

THE IMPACT OF CHEMICALS oUSED IN QUACULTURE UPON THE ENVIRONMENT

The burgeoning population of India times. After the 'green revolution', India has demands adequate food production atld stepped into the 'blue revolution' with employment generation to cope up with the several breakthroughs. Till the last 18th

72 Seshaiyana VoL4 No.1 1996