2025 Surveys Point to Promising Coho Recovery in Pine Gulch Creek

By Watershed Stewards Program Corpsmember Valentin Kostelnick and Scientists in Parks Intern Vienna Rist, San Francisco Bay Area Inventory & Monitoring Network

Watershed Stewards Program Corpsmember Valentin Kostelnick surveying salmonid habitat in Pine Gulch Creek in July, 2025.

NPS / Vienna Rist

September 2025 - The San Francisco Bay Area Inventory & Monitoring Network’s Coho and Steelhead Monitoring Program focuses on coho salmon because North Bay creeks are a stronghold for the endangered central California coast coho population. However, Pine Gulch Creek, the second largest stream in Point Reyes National Seashore, has struggled to support a coho population. This year has been a different story. The summer 2025 field season on Pine Gulch has wrapped up, and we are happy to report an encouraging year for coho salmon!

Our monitoring team found no coho in Pine Gulch Creek from 2010 to 2021. Meanwhile, nearby Olema and Redwood Creeks witnessed returning adult coho each year. The collapse of coho in Pine Gulch may have been the result of several overlapping anthropogenic factors. These may include agricultural activity on the creek’s fertile floodplains, overfishing, water withdrawals, and/or habitat loss through deforestation and land clearing.

Despite this history, our recent surveys demonstrate that within the last five years, coho have begun to successfully reestablish in Pine Gulch Creek. This could be partly related to changes at three active organic farms in Bolinas, on the creek’s lower floodplains. When the farms realized their summertime water withdrawals were diminishing salmon habitat, they worked with the California Department of Fish and Wildlife, the Marin Resource Conservation District and the National Park Service on an innovative solution. In 2015, they built a series of four water holding ponds on their farmland. The ponds are filled with water from the creek in the winter when it is most plentiful.

In 2015, three Bolinas farms built a series of four water holding ponds on their farmland. Three ponds are filled with water from the creek in the winter when it is most plentiful. The design and location of this one allows it to fill just with rain and flow from the surrounding landscape, without drawing from the creek at all.

NScolari / Courtesy of RCDprojects.org

Now, the farms draw water from the ponds rather than the creek in the dry summer months. This keeps water levels up and improves stream connectivity in Pine Gulch during those crucial months when fry, or baby salmon, mature before migrating into the ocean. These ponds have helped the creek continue powering the agricultural heart of Bolinas, while also supporting coho salmon recovery.

And this year there may be more juvenile coho salmon living in Pine Gulch Creek than at any other time since monitoring began in 1998! This year, we counted a record high of over 900 coho juveniles in the creek. That is a jump from the 600+ we counted in 2022, when the parents of these fish were themselves juveniles. The monitoring team also counted nearly one thousand juvenile steelhead in the stream, which represents an average steelhead year.

Juvenile salmonids are the size of a finger and excellent at hiding under shady logs. So, how do we count them? Though snorkeling in two feet of water may seem silly, it is one of the best ways of counting small fish in a creek. From the bank, it is often difficult to see any fish in a pool. But with their face in the water, a snorkeler has a much better view.

This year, we counted a record high of over 900 coho juveniles in the creek. We also tallied nearly one thousand juvenile steelhead in the stream, which represents an average steelhead year. In this clip, the lighter fish is a coho among steelhead.

NPS

That said, it takes an experienced snorkeler to accurately tally large schools of small swirling fish. Complicating matters, schools are typically multi-species, comprised of juvenile coho, steelhead, and sometimes Chinook. It’s like counting a red-winged blackbird murmuration in the evening; it can be done, but it takes dedication and practice. Our snorkel surveys are led by Fishery Biologist Mike Reichmuth and Fishery Crew Lead Brentley McNeill, whose skills have been honed through a collective 30+ years of snorkel experience!

The juvenile coho that our team counted this summer were hatched during the record-breaking 2024-25 winter season. Our spawner surveys that winter documented nearly 30 salmonid redds (nests) on Pine Gulch. Because steelhead and coho redds can appear indistinguishable, we sometimes identify the redds the following summer by which juvenile species we observe swimming nearby during snorkel surveys. Now we know that a few of those redds were indeed coho salmon redds. This is one of the many benefits of our monitoring program tracking multiple coho life stages.

While we don’t know all of the reasons behind coho salmon’s return in Pine Gulch Creek, the promise of a growing cohort is our biggest takeaway from the 2025 juvenile monitoring season. We’re also heartened to see the steelhead population remaining healthy and strong. Since we don’t monitor Pine Gulch fish as smolts migrating out to sea, we look forward to seeing these coho and steelhead return as adult spawners in the winter of 2027-28!

For more information

• San Francisco Bay Area Network Salmonid Monitoring webpage
• Pacific Coast Science & Learning Center Coho & Steelhead webpage
  • San Francisco Bay Area Coho and Steelhead Blog
• Contact Fishery Biologist Michael Reichmuth

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