Looks to be a juvenile keeping an eye on fish outside the “Tank”.
From the Field, Video Snippet, Justine Kibbe, November 30, 2018
https://aa8816.a2cdn1.secureserver.net/wp-content/uploads/2018/12/HH-Great-Blue-Heron-11-30-18.jpg?time=1728555160477852fic0n5ervhttps://aa8816.a2cdn1.secureserver.net/wp-content/uploads/2017/07/fi-Conservancy-logo350x100.jpgfic0n5erv2018-12-01 07:59:462019-01-06 10:18:07Hay Harbor’s Great Blue Heron