By Bailie Doll:
We met with Sara, Teddy, and Erik at Leo T. Cronin Fish View Area on November 15, 2019. This area is in the Lagunitas Creek watershed and covers around 103 sq. miles. The largest tributary inside of this watershed is the Olema creek. They informed us about some of the salmon counts that they recorded last year. Some of their numbers included 55 Chinook salmon, 4 Pink salmon, 1 Chum salmon, and 754 of the local species of Coho and some Steel-heads as well. These specific Coho are protected under the Endangered Species Act because they were deemed to be a separate species of Coho Salmon and are listed endangered. Furthermore, the steel-head are on the ESA’s threatened species list. This area, Lagunitas watershed, supports up to about 20 percent of the Central California Coast wild Coho salmon, which is a large amount for the region.
Salmon are endangered because we carry out the four H’s, which are Harvest, Hatcheries, Hydro, and Habitat. People have logged this area heavily, causing an increase in fine sediment erosion, which can be extremely impact on the salmon especially when they are young. Increased development also leads to higher runoff due to the high amounts of impervious surfaces we have created in the watershed. Another impact major impact is climate change, which will increase temperature and alter historic ranges. Dams negatively influence the fish populations because they hold 50 percent of the habitat the that they would historically have access to. A shortage of winter habitat is the primary limiting factor of salmon survival in this watershed.
How can we help this issue without removing the dam? One thing we can add in more woody debris that will increase the habitat and slow down the water to allow the fish to be able to slim up the creek easier. Also creating a healthier riparian shoreline will stabilize the water’s temperature to the range salmon can survive in.
1st Site
Preston Brown is the director of watershed conservation for the grassroots organization Salmon Protection and Watershed Network (SPAWN) which is supported by the larger organization, Turtle Island Restoration Network. They are dedicated to protecting migratory marine species that are very threatened or endangered. SPAWN, which is about 20 years old, is their local project which is based only in the lagunitas creek watershed. They have a local plant nursery that is fully supported by volunteers which come every Friday and are guided by limited staff on site.
He went on to discuss the most current project they have been spearheading. They are on the second phase of a flood plain restoration project that is hoping to address the limiting factors of coho salmon survival in their winter habitats. At this site they are working toward stabilization of the bank and restoring the creek by adding in mounds of willows to slow down the waters flow. To stabilize the bank they installed biodegradable mats made of coconut and added hydro-seed (mulch made of seeds and paper) along with woody debris on top to give the habitat a kick start. On the steeper slopes by the creeks edge they added a thicker mat to give it extra support and protection from the water flowing. They also placed living trees covered in mud under the steepest areas to add living tissue in the ground to hold onto the loose soil and sediment.
We walked up the creek a short ways and looked at another experimental restoration location. On the higher elevation of the stream (left of the picture below) the water flows through a gravel lens into a smaller section of the stream. They created this structure to insure the perennial off-channel stream has cool oxygenated water. In this area of the stream they are trying to promote the California freshwater shrimp. They created a lattice of willow stems that had space underneath to encourage the shrimp habitat.
2nd Site
Brown took us to the headquarters of SPAWN just down the road, which also had a restoration project completed the previous year. This was a larger project that impacted 1,200 feet and 5 creeks of the watersheds network. He showed us photos of the site during the previous winter while it was flooded and flowed for 20 consecutive days. Since then an abundance of riparian vegetation has filled up the habitat. At this point the project is complete but they are following up with 2-3 years of adaptive management of the site.
Q&A
During our lunch break we met Eric Ettlinger who is the aquatic ecologist and works for the Marine Municipal Water District. One of the main topics we discussed was the process of doing a successful restoration project. First is the planning stage. They have to raise money through grants, talk to stakeholders. The also need to do permitting, design and construction of the project. Usually they have to change their plans from the original project to conform to obstacle they come across.
3rd Site
After our break we walked down to the bridge and devils gulch. They showed us some other projects that Erik and his organization worked on, where they added more woody debris into the creek. He explained how they used the technique of “cabling” that involves a thick cable being drilled through the log and attached to a stable point on the bank to hold the log in place. Down the path we came across some pink ribbon in a tree. Eric explained that the way they marked redds that had been recorded is by putting pink flags.
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