Quality > Hot
Topic: Salmon Habitat
How does logging affect salmon?
Everyone in Oregon knows that salmon are in trouble. Their numbers have dropped 90% from
historic levels. Many species have already gone extinct, and many others are in danger of
Many factors have contributed to salmon decline, including agriculture, urban
development, dams, fisheries, and forestry. Natural predation and ocean currents
also play a part. Roads and timber harvests can increase the amount of sediment
in streams. Removal of trees along streams causes higher water temperatures.
Past logging practices such as splash dams scoured out entire streambeds, destroying
Until recently, fish and wildlife regulations required loggers to remove logs
from streams because fisheries scientists thought that would make it easier
for salmon to get upstream to spawn. Nowadays scientists believe that salmon
need large amounts of woody structures where they live: logs in streams trap
spawning gravel, and create calm hiding places for young fish.
All aspects of logging and forest road
building are now strictly regulated by the Oregon Forest
Practice Rules. These rules are constantly being updated
to reflect the latest scientific knowledge. For instance,
there are now buffer strips along most streams where no
trees can be cut.
Many forest landowners are doing even more. They are volunteering to help
restore salmon habitat by placing logs in streams, planting conifers next to
streams, replacing culverts that block fish passage, and upgrading older forest
roads. Today, roads and culverts are designed to maximize protection of streams
However, logging is only part of the picture. Many other human activities, such as fishing,
mining, agriculture, and development, have negative effects on salmon. Dams block upstream
migration and kill young fish heading downstream. Unfortunately, we know very little about
what is happening in the ocean, where salmon spend most of their lives.
The Oregon Plan for Salmon and Watersheds is trying to improve salmon habitat and restore
healthy populations of salmon to our state. To learn more, visit the
Oregon Plan web site.
For more details on salmon and the problems they face, take a look at this
Snapshot of Salmon