Hi Mrigendra

There many storks, cranes, and herons in India. The one we're talking about--the open billed stork--feeds almost exclusively on snails. It has a white head, neck and body but a black tail and wing tips. It's beak has a gap between upper and lower parts when closed. In Hindi it is called gungla, ghonghila or ghungil. Cf. ENVIS Centre on Avian Ecology list of Vernacular Names of Indian Birds:
http://bnhsenvis.nic.in/Vernacular%20Names%20of%20Birds.html

Bagulaa properly refers to a bird with a black body and white head and neck, the 'white necked stork'. ENVIS lists the Sanskrit name of this bird as Shwetakanth mahabak - ie. ^sveta-ka.n.tha mahaabaka 'white throated great heron'. I might add that this has no Pali equivalent.

The link between the Pali name sithilahanu and the stork seems to be based on a fallacy initiated by Raghu Vira in 1949. But rather than discuss it here I will post a link to my research when I blog it on Fri. (It involves Devanagari and Bengali script, as well as Chinese characters and Unicode diacritics). Unfortunately the meaning of sithilahanu seems to be lost, but I'd be happy to hear from anyone who could definitely say otherwise.

Regards
Jayarava