Genetic Assessment and Management

Genetic diversity is an important component of population resiliency, providing a varied toolbox fish rely on to adapt to a changing environment. Small, isolated populations inevitably lose genetic variability over time and become more distinctive genetically from other populations. Simply by characterizing genetic patterns within and among populations across a landscape, then, we can glean insight as to their relative size, history, and connectivity — important factors for assessing conservation status and needs.


In this study we used genetic characteristics to evaluate the impacts of fire on native redband trout populations in Idaho. We surveyed genetic diversity of trout in 55 tributary streams varying in impacts from wildfire. We expected wildfire disturbance would have reduced local population sizes, and therefore genetic diversity, compared to populations that had not experienced fire in recent history. Our results, however, showed little evidence of these influences. Instead, the level of genetic diversity was lower in fish collected upstream of culvert barriers, suggesting that human-caused isolation may pose greater threats to populations of native trout than wildfire.