A 3 hour circular walk around Cardiff Bay was generally quiet . A Common Sandpiper and 3 Turnstone were along the Ely embankment . Lesser and Common Whitethroat , Blackcap and Reed Warbler were seen near the boardwalk area at CBWR . 7-8 Swift seen in total with lots of Sand and House Martin and a total of 11 pairs of GC Grebes with chicks of varying ages .