High-elevation headwater streams that provide refuge for native bull trout and cutthroat trout would remain cold enough even under the worst warming scenarios to protect and support them. These streams, in places like Central Idaho’s White Cloud Mountains, can carry these native trout through the global warming bottleneck – when many species will disappear – that scientists say the world faces even if nations are able to stop the rise in greenhouse gases. “They are like Noah’s ark for bull trout and cutthroat,” Isaak said.
In February, Isaak and Young briefed forest officials and others working collaboratively across Idaho to restore the health of forest ecosystems while providing jobs for rural communities. The briefing gave local land managers like those on the Boise National Forest a chance to see how their plans fit into these “climate shields.” “There were a few areas in the Lowman District and in the upper Boise,” said David Olson, a Boise National Forest spokesman.
Said Isaak: “The hope is that the information provides a strategic tool that can be used to make more efficient local investments in stream restoration and protection projects, so that the broadest possible distributions of cutthroat trout and bull trout remain later this century.”
Isaak’s Noah’s ark approach won’t just help aquatic species, but also can help managers determine what other habitat will remain viable as warmer winters, earlier runoff and increased wildfire accelerate with warming temperatures. Wolverine biologists are looking at many of the same areas, Young said. Pika, lynx and other mammals that depend on cool summers or good snowpack may find refuge in Idaho’s high country.
This story describes a concrete step towards being strategic about climate change by identifying areas that should be used to build the ‘ark.’ Unfortunately, it doesn’t make the connection to national forest plans, where strategic choices about management priorities need to be made. It will be interesting to see how the Nez Perce-Clearwater forest plan revision incorporates this strategy.