Journal Summary: Predicting Brook Trout Occurrence in Stream Reaches throughout their Native Range in the Eastern United States Brook Trout Salvelinus fontinalis are a popular sport species, but their conservation status is of great concern because many eastern populations have declined. Brook Trout are a paradox. From a basin perspective, they are still present throughout most of their range, but at a watershed or subwatershed scale, many populations are now extinct via local factors that may operate at the reach scale. Therein lies the problem; to conserve Brook Trout fisheries, managers need local information at the smallest scale possible, but up to now that has been largely unobtainable because it would require expensive and extensive field data from individual stream reaches. However, a new approach by Jefferson DeWeber and Tyler Wagner allows prediction of Brook Trout occurrence with the extremely fine resolution that has long been needed.