Fascinating. Not only are there many tree species that need fire to regenerate, there are species of wildlife adapted to living off burned over forest.
... This forest rejuvenation begins in the first spring after the fire. Native wood-boring beetles rapidly colonize burn areas, detecting the fires from dozens of miles away through infrared receptors that these species have evolved over millennia, in a long relationship with fire. The beetles bore under the bark of standing snags and lay their eggs, and the larvae feed and develop there. Woodpecker species, such as the rare and imperiled black-backed woodpecker (currently proposed for listing under the Endangered Species Act), depend upon snag forest habitat and wood-boring beetles for survival.
One black-backed woodpecker eats about 13,500 beetle larvae every year — and that generally requires at least 100 to 200 standing dead trees per acre. Black-backed woodpeckers, which are naturally camouflaged against the charred bark of a fire-killed tree, are a keystone species, and they excavate a new nest cavity every year, even when they stay in the same territory. This creates homes for numerous secondary cavity-nesting species, like the mountain bluebird (and, occasionally, squirrels and even martens), that cannot excavate their own nest cavities. The native flowering shrubs that germinate after fire attract many species of flying insects, which provide food for flycatchers and bats; and the shrubs, new conifer growth, and downed logs provide excellent habitat for small mammals. This, in turn, attracts raptors, like the California spotted owl and northern goshawk, which nest and roost mainly in the low/moderate-intensity fire areas, or in adjacent unburned forest, but actively forage in the snag forest habitat patches created by high-intensity fire — a sort of “bedroom and kitchen” effect. Deer thrive on the new growth, black bears forage happily on the rich source of berries, grubs, and small mammals in snag forest habitat, and even rare carnivores like the Pacific fisher actively hunt for small mammals in this post-fire habitat.
In fact, every scientific study that has been conducted in large, intense fires in the Sierra Nevada has found that the big patches of snag forest habitat support levels of native biodiversity and total wildlife abundance that are equal to or (in most cases) higher than old-growth forest. This has been found in the Donner fire of 1960, the Manter and Storrie fires of 2000, the McNally fire of 2002, and the Moonlight fire of 2007, to name a few. Wildlife abundance in snag forest increases up to about 25 or 30 years after fire, and then declines as snag forest is replaced by a new stand of forest (increasing again, several decades later, after the new stand becomes old forest). The woodpeckers, like the black-backed woodpecker, thrive for 7 to 10 years after fire generally, and then must move on to find a new fire, as their beetle larvae prey begins to dwindle. Flycatchers and other birds increase after 10 years post-fire, and continue to increase for another two decades. Thus, snag forest habitat is ephemeral, and native biodiversity in the Sierra Nevada depends upon a constantly replenished supply of new fires.
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The black-backed woodpecker, for example, has been reduced to a mere several hundred pairs in the Sierra Nevada due to fire suppression, post-fire logging, and commercial thinning of forests, creating a significant risk of future extinction unless forest management policies change, and unless forest plans on our national forests include protections (which they currently do not). This species is a “management indicator species”, or bellwether, for the entire group of species associated with snag forest habitat.
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