Methods, apparatus, systems and articles of manufacture (e.g., physical storage media) to implement power efficient detection of watermarks in media signals are disclosed. Example watermark detection methods disclosed herein include operating a watermark detector in a first operating mode to search for a first watermark in a media signal. Such disclosed example methods also include, in response to detecting the first watermark, determining whether the first watermark satisfies a first condition. Such disclosed example methods further include, in response to determining the first watermark satisfies the first condition, operating the watermark detector in a second operating mode in which the watermark detector cycles between a sleep interval and an active interval to detect a second watermark at a second location in the media signal relative to a first location of the first watermark in the media signal.