Vol. 110 - Part III - Zoological Survey of India

110 Rec. zool. Surv. India24. Antarctic Tern : Sterna vittata Gmelia : Thisbird was sighted only in 22 nd expedition and recordedits wide zoo-geographical distribution from 48°S to 61°Slatitude. But during the 1 st expedition, the bird wasreported only from temperate zone (Parulekar, 1983).25. South Polar Skua : Catharacta skuamacormicki (Saunders) : (Fig. 2). Adults stay nearbreeding colonies in the Anatarctic zone during thesummer, but during the off-season it may range northto sub-tropical waters (Watson, 1975). This bird wassighted only in Antarctic zone during both theexpeditions.26. Adelie Penguin : Pygoscelis adelia (Hombronand Jacquinot) : These are the most common penguinspecies in the East Antarctica. In both the expeditionsa good number of birds were sighted from 60° to 70° Slatitude and 10° – 40° E longitude.27. King Penguin : Aptenodytes patagonicuspatagonicus Miller : The bird was sighted in the 15 thexpedition near the Prince Edward Island (45°S and 69°E). The bird is known to breed in South Georgia.28. Emperor Penguin : Aptendytes forsteri Gray :Earlier report says that Emperor penguins breedregularly during winter in more than 30 colonies aroundthe shores of the Continent and adjacent islands.Mostly the birds were sighted in between 66°S to 71ºSlatitude during 15 th and 22 nd expeditions.DISCUSSIONThe studies made separately on occurrence anddistribution of different bird species sighted in 15 th and22 nd Indian Antarctic expeditions during voyagethrough Indian and Atlantic Oceans Recorded 28species including 14 species as common in occurrencein both the expeditions. Among different bird groupsPetrels were dominant in number of species followedby Albatrosses. Record of Lesser number (14 spp.) ofbird species during 22 nd expedition than the 15 thexpedition (23 spp.) may be due to shorter travel timeand for shorter route and also for lower temperature inAtlantic Ocean. These may have some impact onspecies make-up and distribution. This was evident byabsence of some birds species in the 22 nd expedition(Table-1).The result also showed that except WanderingAlbatross which was recorded in Antarctic zone allother Albatross species were found to occur betweentemperate to Sub-Antarctic zones. Two species ofPenguins, Adelie and Emperor were observed in all thethree zones, being maximum in Sub-Antarctic andAntarctic zones. Only King Penguin sighted in 15 thexpedition were found to distribute in Sub-AntarcticIslands. Among the Petrels, Cape Petrel, Antarctic Petrel,Giant Winged Petrel and Snow Petrel were found totolerate much lower temperature as they mostly live inSub-Antarctic and Antarctic zones. Many of the otherbirds recorded in this study are known to occur inAntarctic zone but they are here observed to live intemperate and Sub-Antarctic zones.But it is very early to say, whether these changesare occurred due to the climatic changes of SouthernOcean, or non-availability of food in the SouthernOcean or insufficient data of Avifauna of SouthernOcean.Present day Polar Regions experience greater ratesof climate change than elsewhere on the planet. Thefauna of these regions is uniquely adapted to theextreme environments in which they exist, and may bevulnerable to shifts in climate. Climate change is havingimpacts on both marine, and terrestrial, and limneticsystems, and hence will influence future biologicaldiversity.In view to above, it has been clearly understoodthat the Antarctic research in future will not be themere listing of species but also essential to developthe long-term monitoring programme to have a betterunderstanding the causes of changes.ACKNOWLEDGEMENTSWe are thankful to the Director, Zoological Surveyof India, Kolkata for providing facilities andencouragements. Thanks are also due to Dr.A.K.Sanyal,Addl. Director, Zoological Survey of India, Kolkata forhelping in the preparation of the manuscript.