<p>Thousands of native and migratory birds are flocking at the Rajdhani reservoir in Patna during this winter season. The reservoir is spread over 12 acres. The reservoir has become buzzing these days with the arrival of indigenous and foreign birds. The arrival of these migratory birds started as soon as the cold comes.</p>.<p>More than 20 pairs of native and foreign birds have been seen in the reservoir. There, birds of more than 4,000 different species have arrived. These birds migrate every year at the end of October and stay till February.S Kumar, DFO Patna informed that last year 42 species of migratory birds arrived here.</p>.<p>He said, “Last year 42 species of migratory birds arrived here. They start coming every year towards the end of Oct and stay till Feb. We're expecting over 42 species of birds this year.”</p>