Trackers on sea turtles, fish, dolphins, and other animals send data to researchers about where its wearer travels, to what depths the animal dives, and more. This information is important for learning about different marine species and protecting them. At the same time, if the instruments subject animals to a lot of extra drag, that means just moving through everyday life requires a little more energy. Over long periods, that could reduce animals' ability to grow, survive, and reproduce. It could even make it harder for an animal to zoom away from a predator.