By Doyle Irvin, American Forests
Fishermen in the west used to say that the rivers were so full of salmon, you could walk across the river on their backs. Then, these fish were overharvested, their habitats were degraded, many rivers were dammed by hydropower plants and higher water temperatures allowed diseases, such as gill-rot, to flourish where they hadn’t before. Those fisherman wouldn’t tell such tales today: the Pacific salmon is considered extinct in more than 40 percent of historic river habitat.
Some of you may be thinking, “Salmon live in the water. What do they have to do with trees?” This is a good question to ask! The link between salmon and trees is multi-faceted and wildly interesting — both hugely benefit from each other in their struggle for survival.
The first way salmon help trees is by feeding all the various animals that live within the forest. More than 100 different species rely to some extent on salmon for their survival, and these animals benefit the forest in a number of different ways. For example, bears, who rely in large part on salmon and nuts, will dig in the ground looking for seeds and nuts, stirring up nitrogen in the soil. The seeds they eat are then primed for propagation, after passing through the bear’s digestive system.
It gets deeper than that. Many animals who eat salmon will only eat half, leaving the other half to become part of the forest floor, decaying into dirt and providing nitrogen for the surrounding plants. In some areas, up to 25 percent of the nitrogen plants need is provided by salmon. Trees with nitrogen from salmon have been found up to 1,600 feet away from the stream the salmon swam in!
Where it gets really interesting is how the trees help the salmon. Tree communities prevent erosion, keeping the water clean enough for aquatic life to survive. Trees also create eddies where the fish can rest and catch a break during their migrations. On top of that, salmon also lay their eggs in cool areas, which means that they need shaded streams to reproduce. Finally, forests house the insects that young salmon feed on before heading to the ocean.
Unfortunately for both the trees and salmon, agriculture and industrial logging have cleared many of the river banks in the states bordering the Pacific. The wildlife that once flourished in this riparian environment — elk, bears, goats, cougars, eagles, swans and many, many more — is largely gone. The good news is that American Forests is dedicated to the restoration of these vital habitats!
In the last three years alone, American Forests been busy planting nearly half a million trees in riparian environments across the west coast. This winter, with our Home for the Holidays initiative, we are doubling down on our commitment to protect these invaluable parts of our wildlife. Join us in our contribution to the planet with a contribution of your own.