By Carl Zimmer
Islands of greenery, called refugia, survive even the worst fires, sheltering species and renewing charred landscapes.
Forests have burned in spectacular fashion this year. From California to Colorado, Portugal to Greece, photographers have captured terrifying images of infernos soaring into the sky and spreading to the horizon.
The fires left scenes of ashen destruction, but they did not wipe out everything. Scattered about the ravaged landscapes were islands of trees, shrubs and grass that survived unharmed.
It’s easy to overlook these remnants, which ecologists call fire refugia. But they can be vital to the long-term well-being of forests. These havens shelter species that are vulnerable to fires. Afterward, they can be starting points for the ecosystem’s regeneration.
“Those trees are lifeboats,” said Meg Krawchuk, a fire ecologist at Oregon State University.
Writing recently in the journal BioScience, Dr. Krawchuk and her colleagues argued that it’s urgent to better understand fire refugia, because they may be seriously threatened in future decades by climate change. Without them, many species may become threatened and the surrounding ecosystems may take longer to recover from wildfires.