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Fire and Animals
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Many animals rely on the shape and height of shrubs and trees,
called the vegetative structure, and are displaced when fire removes
that structure from an area. Deer and elk which rely on certain
vegetative structure for hiding and thermal cover, often avoid severely
burned areas until some browse returns. Gophers and ground squirrels
often avoid even intense fires by hiding in their burrows, but their
survival is determined by how much of their food supply remains.
Birds usually escape fire, but their young may not if a fire occurs
during nesting season. Canopy-nesting and canopy-feeding birds are
often displaced by canopy fires. Other species, like woodpeckers, may
move into a canopy burned area to take advantage of insect populations.
Whether a particular species depends on whether the necessary feeding,
nesting and rearing habitats remain.
Fire has an effect on insects, both beneficial and pests. Since
fire changes the environment in which they live, the effect can be a
direct or indirect kill. Fire control policies of the last 75 years
have greatly increased insect pests. Insects moving into burned forests
increases the number of insect eating birds such as the woodpecker.
Since many insects spend part of their life cycle on the forest
floor, light ground fires provide a direct control method. In the
Pacific Northwest, several insect pests spend the winter months on the
forest floor. Fire can be used as a control method because ecosystems
where these pests occur are adapted to fire by trees with thick, heat
protecting bark. But this type of control can only be used periodically
since fire consumes fuel and it takes between four and five years for
that ground fuel to build up again.
From - Fire in Pacific Northwest Ecosystems, produced and
distributed by the Environmental Education Association of Oregon and the
Pacific Northwest Wildlife Coordinating Group, p. 152-3.
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