Fish biologists often need to capture and tag fish in order to monitor their behavior and movements in the wild. However, the process of capturing the animals and implanting transmitters can be stressful and alter the behavior of a fish, thereby biasing research results. By studying the physiology of a species we gain basic information that is needed to modify our research so that it has minimal to no impact on the fish. For example, Abernathy FTC physiologists recently evaluated the effects of numerous tags in hatchery-reared Pacific lamprey. This information may be critical in monitoring reintroduction and habitat use by this species. In that study, the effects of various tags on growth, burrowing and survival were evaluated. By determining which tag type has the least impact on natural behavior, we can ensure that tagged lamprey used in relocation efforts behave the same as their wild counterparts.