Figure 4.

Refuge habitats (solid ellipses) for cold-water fishes provide short-term shelter from risks (dashed ellipses), but are also critical for long-term species persistence within the stream network that, as a whole, constitutes a climate refugium. Areas of risk can encompass refuge habitats of similar or contrasting risk within them (eg cold-water refuges nested within the drought-risk portion of the stream network). In addition, a refuge from invasives created by the presence of a barrier (black bar) that prevents invasion by predators or diseases can also potentially be encompassed by an isolation risk if the isolated population is too small to persist in the face of stochastic (random) disturbance events within the watershed.