Electronic tags reveal the hidden lives of fishes

摘要

The past six decades have seen the emergence of new electronic tag technologies enabling scientists to remotely study the behavior of fishes in a wide variety of aquatic habitats. This revolution began in the 1950s and 1960s with the first studies utilizing acoustic and radio transmitters to actively track fish movements. Subsequent decades saw the development of passive monitoring systems enabling researchers to scale up the number of individuals followed, and the duration and spatial extent of tracking studies. Recent decades also have witnessed the increasingly-widespread use of sophisticated satellite transmitters to quantify fish movements in remote parts of the ocean beyond the range of fixed listening arrays. Most recently, high-frequency sampling devices incorporating accelerometers and other novel sensors have given us unparalleled new and detailed insights into fish behavior. All of these technologies have yielded important insights into fish spatial behaviors, and shown that many species are most active at night, or in deep waters, but we need better ground-truthing to reveal the full context and purpose of these spatial patterns. Recent advances in animal-mounted cameras have provided important ground-truthing breakthroughs, allowing us to see behavior and habitat use from the fishes' own perspective. However, current generations of animal-mounted cameras are reliant on natural light, or use artificial light overlapping the visual spectrum of most fishes. To see what fishes are doing at night, we need to develop new animal-mounted cameras using far red spectrum light, or high-frequency sound, to illuminate the view field without impacting natural behavior.