An anchor has a shank pivotally connected to a fluke structure via a pivot mount for rotation between locked and release configurations. The shank has a locking surface distal from the pivot mount engaging a portion of the fluke structure to resist the rotation in the locked configuration. An elastically deformable member couples the shank to the pivot mount and the rotation of the shank may require the deformable member to be elastically deformed and the locking surface to be displaced toward the pivot mount. A float may be attached to the shank at a position spaced away from the fluke structure. A pulling force component applied to the shank in a direction from the pivot mount toward the locking surface may provide greater resistance to rotation of the shank. Other anchor embodiments are also disclosed.