Ever since Gearhart photographer Neal Maine read Amy Gulick’s Salmon in the Trees: Life in the Tongass Rain Forest (2010: Braided River), he has been attempting to capture, with his camera, the salmon-forest connection here on Oregon’s north coast. The critical contribution salmon make to the functioning of forests has been well documented and is nicely summarized in this excerpt from an essay by Liz McKenzie on the website Encounters North:
“It begins deep in the ocean where millions of salmon grow and feed, taking in ocean nutrients, such as nitrogen and phosphorus. When their sea time is up, salmon return to the place of their birth to give birth, and to give their lives to the next generation.
“The bodies of spawned-out salmon fertilize the stream and help to provide food for insects and microorganisms, which then nourish the young salmon after hatching.
“This story also begins with raucous crowds of seagulls gorging on salmon eggs; with cantankerous brown bears vying for position beside a stream filled with salmon; and it begins well upriver from the coast, in the forest fertilized by nutrients brought by salmon from the distant reaches of the sea.”
Here Neal shares some thoughts and images about the salmon-forest connection in North Coast Land Conservancy’s service area.
Your first clue that the salmon have returned to Thompson Creek, Circle Creek, or any of the salmon-bearing streams on the Oregon Coast might be a fluttering at the water’s surface; look closer and you’ll see fins waving to hold in the current, then flashing to make a dash upstream. These are chum salmon returning to the Necanicum River.
In the right light and in a clear stream, such as here in Thompson Creek, coho salmons’ red sides stand out against the gravel streambed.
Watershed rainfall fills the pathway to the upper reaches of coastal streams and rivers.
Many forces work against the salmon’s return, including the fishing lure embedded in this fish’s jaw. This coho is attempting to jump a waterfall on Coho Creek, just below Seaside Heights Elementary School.
Just past those falls, Coho Creek runs under Spruce Loop, the road to Seaside Heights. The good news is that this potential barrier, a poorly designed culvert, has been replaced by a salmon-friendly passage system.
Upon deposit of the salmon eggs in the fine gravels of the creek bed, a single cell on the surface of the egg begins to reorganize the contents of the egg into a tiny salmon.
It is a one-way trip for salmon; after spawning, they die, exhausted, their final life task achieved. Meanwhile the watershed has been waiting, arms open, for this special delivery of life-giving nutrients.
The salmon’s flesh becomes forest via the myriad creatures of the water, land, and sky that feed off the decaying carcass.
The otter, for example. This one has a salmon smolt in its mouth. Otters also eat the flesh of dead salmon at the water’s edge. When otters, bears, or other mammals drag salmon into the forest to feed on it, much of the remains are left behind. When they defecate, more salmon nutrients are spread on the forest floor, further feeding the forest. In a study of British Columbia’s Great Bear Rainforest, ecological economist Pavan Sukhdev estimates that 80 percent of the nitrogen in that forest’s trees comes from salmon.
Juvenile coho salmon spend a year and a half in freshwater before migrating out to the ocean. While in coastal streams, they feed on organisms that were fed by nutrients falling from the sky and swimming upstream, via the last salmon run. The nutrients that fall to the stream in the form of dead leaves and other aerial debris are consumed by the in-stream invertebrates. As gravity pulls at the stream, these nutrients get washed downstream—a constant process of de-nutrifying the stream. Returning salmon bring nutrients from the ocean back into the watershed.
Beaver dams, such as this one on China Creek (a tributary of Neawanna Creek) make giant nurseries. The greater surface area created by beavers damming streams increases the rearing capacity, food supply, and ultimately the survival rate of juvenile salmon. You can’t grow a garden on top of a flagpole.
Woody debris—felled by wind or beavers or eroding streambanks—contributes to the food chain. Tiny invertebrates (insects) living in the stream feed on the decaying wood. Salmon and other creatures then feed on these invertebrates. Such debris also slows the stream and creates places for juvenile salmon to rest and hide in the year-plus they spend in fresh water.
This forest chickoree, perching on a narrow limb, can thank the salmon for its habitat.
To learn more about the salmon-forest connection, Neal recommends reading “Salmon as Nutrient Pumps: New Lessons in Watershed Health,” an article from Oregon Sea Grant.
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