Scientists believe the fiery coloration is a trade-off. In dark coniferous forests, a red coat against green needles and brown bark offers surprisingly good camouflage—especially during autumn when larch needles turn amber. But in deciduous woods, they stand out like warning flares. This is why fire reds thrive best in dense, old-growth spruce and pine stands, where shadows run deep and the canopy filters sunlight into shifting mosaics of gold and black. In Sami folklore, the fire red squirrel is called Ruostegierdu —"the rust wanderer." One legend tells of a great forest fire started by the god of thunder. As the flames consumed the world, a small squirrel ran from tree to tree, carrying a burning twig in its mouth to replant fire in the hearts of the surviving trees. The smoke stained its fur forever. To this day, elders say, if you see a red squirrel with a tail that seems to flicker, it still carries that ember.
In Ireland and Scotland, conservationists have established “red squirrel strongholds”—islands of native woodland where grays are systematically excluded. Within these refuges, the fire red morph sometimes reappears after decades of absence, as if a long-dormant genetic switch were flicked on again. Dr. Emilia Voss, a geneticist at the University of Aberdeen, calls them “phantoms of the forest floor.” fire red squirrels
Estonian peasants believed that killing a fire red squirrel would cause one’s own hearth to go cold. In parts of rural Sweden, farmers would leave out small bowls of lingonberry jam in winter, hoping to lure the “fire-sprite squirrel” to their barns, believing it would protect stored grain from lightning strikes. Scientists believe the fiery coloration is a trade-off
Science offers no such magic, but observation reveals a kernel of truth. Fire red squirrels are notably more aggressive and territorial than their duller counterparts. Researchers in the Białowieża Forest of Poland found that redder males won more disputes over food caches and mated more frequently. In effect, the fiery coat signals —a visual warning: I burn bright. Do not test me. A Landscape Shaped by Fire The fire red squirrel’s destiny is intimately tied to wildfire. Unlike the gray squirrels that dominate North American suburbs, fire reds evolved in boreal and mixed forests that experience periodic, low-intensity ground fires. These fires clear undergrowth, stimulate conifer cone production (especially Scots pine and Norway spruce), and create the open, mossy floors where the squirrels love to forage. This is why fire reds thrive best in
But perhaps the squirrel has one more trick. In 2023, researchers discovered that fire red individuals in northern Sweden have begun choosing to nest in recently burned areas, where fresh growth of fireweed and raspberry offers abundant food. They are adapting—not fleeing from fire, but returning to it.
And so the story continues: the ember does not extinguish. It only waits for the right wind, the right forest, the right shadow, to glow again. “The fire red squirrel is not an animal of comfort,” says old Sami proverb. “It is an animal of survival. Where you see it, the forest still remembers how to burn and how to grow.”
But here lies the crisis. Climate change has altered wildfire regimes. Fires now burn hotter, larger, and more frequently—often too fast for any animal to escape. In the catastrophic 2021 Siberian taiga fires, an estimated perished, including entire populations of fire reds. Unlike the more numerous common reds, fire red variants are already rare (perhaps 1 in 10,000 individuals). Their genetic niche is being erased. The Gray Invasion and the Fading Ember If fire is a threat, the eastern gray squirrel ( Sciurus carolinensis ) is an apocalypse. Introduced to Europe from North America, grays outcompete reds for food and carry squirrelpox virus—harmless to themselves but 90% fatal to reds. Fire reds, with their higher metabolism and smaller population pockets, are especially vulnerable.