PELICAN (PELICANUS PHILIPPENSIS) MIGRATION LINKED TO MONSOON WIND DIRECTION

摘要

Pelicans (Pelicanus philippensis), long distant migrant birds arrive between October and December to South East Coast wet lands of South India Viz. Nelapattu bird sanctuary (Nellore District) Uppalapadu (Krishna District) Vedamthangal sanctuary, TamilNadu (Balachandran, 1995; Nanda Kumar etal., 2010; 2012). A five year study was conducted choosing Nelapattu Bird sanctuary as model study being one of the biggest pelicanary. Sharma and Raghaviah (2002) showed relationship between rainfall and pelicansof Nelapattu. Further detailed exploration was made by Nanda Kumar etal. (2009) for three years from 2006 to 2009 on rainfall amounts and pelican numbers showing statistical I association (Nanda Kumar et ai, 2012). Several navigation causes are suggested for migratory activity of long distant birds from feeding grounds to breeding grounds and vice-versa. But no attempt was made or literature is very very meagre on linking migration of pelicans to wind direction and pattern during vigorous monsoon activity of South India. Whether this seasonal wind direction during monsoon is one of the major facilitative factor for inducing migration is being examined. Nelapattu bird sanctuary was choosen as model for study. It is reported that pelicans arrive from South East Asian Countries and were spotted in Thailand, Philippensis, Indonesia, Sumathra, Vietnam Mynmar, Cambodia (Scott, 1989; Kosel, 1999; Avian web.com, 2012). Satellite weather maps showing clear wind direction from South East of Bay of Bengal and North East Asia to South India coastal areas during October -December and in reverse direction i.e. from South East Coast towards North East and towards east of Bay of Bengal (April/May/June) is presented. The satellite weather maps are retrieved for theperiod from 2009 to 2013, the rain fall amounts, wind directions, and pelican numbers are recorded choosing Nelapattu bird sanctuary as study site and is discussed below.