The dynamic properties and the domain structure of an epitaxial (111) garnet ferrite film with perpendicular anisotropy have been considered in a harmonic magnetic field with an amplitude in the range 0-170 Oe and a frequency in the range 0.2-7.0 kHz. A direct correspondence between the obtained images of dynamic domain structures and particular sections of the hysteresis loops is set up. It has been established that variations in the parameters of the magnetic field lead to qualitative changes observed in the domain structure and, correspondingly, in the shape and area of the hysteresis loops.