Abstract: An apparatus and method for automatically de-energizing electrically operable equipment in response to a lack of animal activity in a specified environment for predetermined time period. The apparatus of the present invention utilizes a circuit which is designed to detect activity which generates energy in a certain wavelength range and particularly, sonic energy in a certain environment and is responsive to the lack of activity within a certain predetermined time delay period or interval. Thus, if an activity which generates sonic energy is detected within a confined environment within the predetermined time interval, a signal is generated to energize or maintain energization of one or more electrical devices connected to the system of the invention. Contrariwise, if no sonic energy is detected within the predetermined time interval, there is a resultant de-energization of the electrically operable equipment. A control is provided to adjust the predetermined time delay period.