The present invention relates to decoys for simulating the movement of animals on land, air, or water. The invention includes a small, enclosed, and portable unit containing a motor, a rechargeable power supply, a timing control mechanism, and a spool attached to a line. The line extends from the unit and attaches to one or more animal decoys and, at the end, to an anchoring mechanism (e.g., an anchor placed in the water or a tether attached to a tree or other stationary support). The anchoring mechanism preferably is attached to the line via a bungee cord or other flexible connection that exhibits elasticity. The preferred embodiment of the invention includes four main parts: (1) a string portion, which extends from an anchor system to a mechanical unit; (2) one or more animal decoys attached to the string portion; (3) an anchor assembly attached to one end of the string assembly for creating tension in the string assembly and securing its position; and (4) a mechanical unit containing a low-power, motorized spool assembly, a rechargeable power supply, a spool, and a timing mechanism for repeatedly winding and releasing the string portion.