Total bird species richness and turnover across seasons at different elevations (m asl) sampled along the river Bhagirathi. Mid-elevations around Uttarkashi showed maximum species richness and showed least species turnover. Lower elevations around Rishikesh and Devprayag (300-700 m asl) showed moderate species richness and high species turnover. Very high elevation around Gangotri showed less species richness.