An important environmental issue facing the marine and hydrokinetic energy industry is whether fish that encounter underwater energy devices are likely to be struck and injured by moving components, primarily rotating turbine blades. The automated analysis of nearly 3 weeks of multibeam hydroacoustics data identified about 35,000 tracks of fish passing a tidal turbine in the East River, New York. These tracks included both individual fish and schools during periods with the turbine absent….Read more

Conducting sample size analysis is important to ensure that sample sizes are adequate to meet objectives for precision but not so large that valuable resources are wasted. When simple survey designs are used, sample size analysis is straightforward. However, creel surveys often follow complex designs that can make sample size estimation difficult. The objectives of this study were to provide sample size estimators for commonly used creel survey designs and investigate sample size requirements to achieve varying levels of precision. For estimates of angling effort, the average sample size among fisheries….Read more

This site is a companion for the AFS book Standard Methods for Sampling North American Freshwater Fishes. Increasingly biologists are adopting these methods so they will be able to compare their data to those collected by other organizations, in other regions, or across time. Read more information about standard sampling in general and how these techniques were developed; comment on specific techniques so those working on future editions can incorporate your ideas; compare your fish data to North American, ecoregion, state, and provincial averages and percentiles; and catch up on the latest research on the validation or “ground truthing” of specific standard methods.