Anthropogenic climate change may have profound effects on stream biotas, most of which are cold-blooded and live in networks that are already heavily fragmented by human development. Concern over potential impacts is driving strong inter-agency collaborations and development of extensive monitoring networks and accurate models for downscaling broad climate patterns to key habitat variables. We provide examples of two such models that provide detailed predictions of stream temperature and hydrology under various climate scenarios across large portions of the Rocky Mountains. New decision support tools have been developed that integrate outputs from these models to provide information at spatial and temporal scales relevant to management. Even as the resolution, accuracy, and amount of data available to inform management decisions increases, key uncertainties remain. For aquatic biotas, these include documenting biological responses to long-term climate trends and estimating minimum habitat configurations below which population persistence is unlikely. Once biological responses are better understood, risk management through strategically targeted conservation actions will be able to proceed more efficiently than is presently the case. Flexibility in management responses will be required to bolster populations where it makes sense to do so, but managers will also have to accept the inevitable losses of some species from portions of historic ranges and expansion of new species into local aquatic communities. Some species will benefit and others will be harmed, but broad distributional adjustments are likely to occur this century. Our ability to accurately translate broad climate trends to effects on key fish habitats has dramatically increased in recent years with the advent of massive stream temperature monitoring networks and application of new spatial analyses for streams.
Click tabs to swap between content that is broken into logical sections.