The Noyo River, Pudding Creek, the Navarro. These are just some of the rivers that flow through Mendocino County. Starting from their headwaters in the chaparral hills, they wind down valleys of redwoods and pour out into the Pacific ocean. The rivers running through our county are some of the last left that still host wild California Central Coast Coho. Central Coast Coho, also referred to as CCC coho, are a genetically distinct subset of Coho Salmon that once flourished from Aptos Creek near Santa Cruz all the way up to the Eel. Old stories tell of rivers filled so thick with salmon that one could cross the river on their backs. But now, the species is on the brink of extinction. They are both federally and state endangered. 

“In the 1940s there were probably estimates of 400,000 coho that used to return to california. The most recent population data from 2018 had about 4,000 coho. CCC coho specifically. So we’re looking at returns that range between 1-6 percent of what historical population estimates were.” 

That’s Anna Halligan, North Coast Coho Project Manager of Trout Unlimited, which is a national conservation nonprofit with a Fort Bragg branch. They nonprofit works to protect cold water fish species and the places they need. You’ll hear from Halligan throughout this story. 

Coho have been present in this region since far before humans arrived and took it over, and Each year, conservationists, fisheries scientists, and fishermen alike hold their breath, waiting to see if the species will make it through another season.

Late this fall, Trout unlimited completed three projects intended to support the Central Coast Coho fishery. They replaced old infrastructure along the Skunk Train’s path that was obstructing fish passage. 

So last week, I went with Halligan down to the location of one of the three project sites to check out the work they had done. The project opened up one mile of previously inaccessible coho habitat that Trout Unlimited claims is critical to the species reproductive success, and so ultimately, their survival. 

“Most people call this the noyo flats. We’re in kind of the upper headwaters of the noyo river. I’m actually standing on what will be a railroad track. I'm on the bed and looking down at what will be on that track.”

The project I went to is located far down in a valley off of the north side of California State Route 20, where, running underneath the Skunk Train’s railroad tracks, the upper headwaters of the Noyo River flow slowly through a landscape of redwoods, alders, and willows. Crouching down on the bank of the newly restored stream bed, I put my hand in the water. It was clear and cold as it moved over a bed of gravel. I didn’t see any fish that day, but Halligan said that endangered central coast coho travel this tributary, downstream to the noyo and out to the ocean to grow big and strong or upstream back to their birthplace to spawn. The project was centered around replacing an old culvert that was blocking fish from reaching a mile of spawning habitat on a small tributary which is unceremoniously named Gulch C. 

“What was here was a pretty small culvert for the size of the channel that we have. We had an undersized culvert that was underneath the railroad bed. Usually when culverts are undersized what will happen is they act like a fire hydrant nozzle. It constricts the amount of water that comes through during storm events and then shoots it out like a fire hose and that causes all this erosion on the downstream end of the culvert. As it erodes the bottom of the culvert becomes what we called perched where it's sitting above the bed of the channel and above the surface of the water so that creates a big jump. Generally when we’re doing this we don’t want to engineer anything that has more than 6 inches of a jump height for juveniles and a foot for adults.”

So basically, the old culvert was creating a cliff that salmon couldn’t get past in order to reach their spawning grounds. The project to reopen the habitat cost around one million dollars and included installing a new corrugated steel 30 foot wide culvert, building and installing a bridge and restoring a section of damaged stream bed. 

“I mean this project will open up a mile of habitat, and I guess you could say that’s not a lot. But that’s a mile that they don't have right now. And I do think that one of the best things we can do to help them as a species is provide them with the most and highest quality habitat.”

Central Coast Coho, which are a metallic looking silver and blue-green fish are a keystone species. That means that other species that share its ecosystem depend on them for their survival and that without them, the ecosystem would dramatically change, likely to the detriment of other flora and fauna that live in it. So basically, they are very important. 

The downfall of coho salmon has had harmful impacts beyond the species and its ecosystem. The loss of the fish left Native communities which once relied on the salmon for nutrition, wealth, and culture, empty handed. It destroyed a central pillar of their communities and livelihoods. It also damaged what was once a large and thriving fishing industry along the coast.

But Trout Unlimited believes that through restoration projects like the ones they just completed on Gulch C, they can bring these fish back to their previous numbers, or at least further away from the tenuous situation they are in now. 

“We have wild returns every year. And there are some places in the range of CCC coho where that doesn’t happen anymore There are places like the Russian where they are keeping the population going through a captive broodstock program. And here we still have wild returns and it’s in the order of thousands of fish so that’s a big deal. We want to take advantage of the opportunity of working in these watersheds where we here still do fish coming back. One of the best things we can  do is give them access to more habitat. The haitat isn’t pristine but it's not completely broken and we know that because we have a population here still. More access to more habitat the better for these fish. Particularly in a changing climate because they need to have the ability to move if conditions are not suitable for them to survive. The Noyo River, the Big River, the Ten Mile River, Pudding Creek, The Navarro, The Albion. Those rivers are so important for recovery. If we can do as much restoration as we possibly can in those watersheds, we have a decent chance of keeping those fish from being extirpated from the California landscape.”