PESHAWAR, Jan 16: Siberian migratory birds like houbara bustard and cranes have started their southward journey to Pakistan with the advent of winter.

An official of the NWFP Wildlife Department said that the birds' arrival gained momentum because of the climate change, adding that they journeyed from Siberia to Pakistan and then as far as to Bharatpur in India.

He said the birds travelled on the 'green route', a major international migration route and covered a distance of approximately 4,700km. The birds initially fly to Afghanistan and subsequently to Chitral, Nowshera, North Waziristan, Dera Ismail Khan, Dera Ghazi Khan, Sukkur before leaving for Bharatpur.

During their journey, the birds make stopovers on lakes, arid areas and water basins. It takes them eight to 11 days to complete their journey. They fly at an altitude of 2,400 metres over the Hindu-Kush and Karakoram mountain ranges.

The migration season starts in December soon after the onset of freezing cold weather in Siberia. The birds start flying back home in March. The migratory birds include waterfowl, teals, pintail, mallard and gadwall, etc. The official said the presence of these birds has a number of ecological benefits. -APP