Mumbaikars can see the flamingoes, after they arrive, at Thane creek, in Airoli, Mahul and Sewri. File pic

Mumbaikars will have to wait for three to four weeks to see huge flocks of flamingoes gather at the Sewri and Airoli creeks. Bird experts said good rains in Saurashtra, where the birds arrive first, and environmental changes are the reasons behind the delay.