BOISE, Idaho (AP) — Federal scientists using new technologies have mapped a Cold Water Climate Shield, an area spanning five western states that could support viable populations of native species if the region continues its warming trend.

Scientists say mapping the cold-water refuges for cutthroat trout and threatened bull trout could help resource managers make decisions aimed at preserving populations of those and other cold-water dependent native species in Idaho, Oregon, Washington, Montana and Wyoming. Scientists say streams in the region have warmed up about a degree over the last three decades and are getting hotter.

Advances in stream temperature sensors and environmental DNA sampling, a new way to find out what species inhabit a stream, have allowed scientists to create the detailed maps.