New Delhi, May 12 (IANS): Calling for bird conservation on "World Migratory Bird Day", Union Environment Minister Harsh Vardhan on Saturday said that India's rich ecology is supported by a wave of migratory species.

Marked with the theme "Unifying our Voices for Bird Conservation", the World Migratory Bird Day 2018 calls for securing and conserving the flyways used by the migratory birds for domestic and international migration.

"The rich ecological wealth of India is generously supported by waves of migratory species that breed, nest and feed here every year. It is estimated that over hundred species of migratory birds fly to India.

"India is playing host to a number of migratory birds in summers and winters. Numerous wildlife sanctuaries set up in the country serve as their temporary habitat. Bird lovers visit these sanctuaries to get a glimpse of some of the rarest species," Harsh Vardhan tweeted.

According to ornithologist Bikram Grewal, over 200 species of birds migrate to India during winters from Asian and European region.

"Lots of birds migrate domestically, though their numbers are not known, there is not much research on that," Grewal said.

During summers, mostly domestic or local migration happens with over 20 species of birds migrating from southern India to northern parts. Many more birds, according to Grewal, migrate from plains to hill stations in India during summer.

"Pied crested cuckoo migrates from Africa to India during monsoon. It is also called the harbinger of monsoon here due to its arrival time," Faiyaz A. Khudsar, scientist in-charge of Yamuna Biodiversity park, told IANS.

According to Khudsar, the migratory birds are indicator of the quality of canopy cover in the forests, which support these birds.

"The motive is to send a message of awareness and tell that these migratory birds bring life along," Khudsar said.