1. A method for monitoring an environment (U) of a vehicle (F), wherein the environment (U) and objects (O 1 , O 2 ) present therein are detected by means of at least a first image detection unit ( 1 ) and a second image detection unit ( 2 ), the detection regions of which at least partially overlap and form an overlap region, wherein an overall image (G) is produced from individual images detected by means of the image detection units ( 1 , 2 ), said overall image (G) showing the vehicle (F) and its environment (U) from a bird's eye perspective, and wherein, depending upon determined positions of the objects (O 1 , O 2 ) in the overall image (G) between a first individual image region (EB 1 ) and a second individual image region (EB 2 ), a progression of at least one boundary line (L 1 to L 3 ) extending from an origin to the image edge of the overall image (G) is predefined so that the boundary line (L 1 to L 3 ) extends away from the objects (O 1 , O 2 ).