Rivers and Streams Blog Posts

It's totally normal for the lower section of Olema Creek in Point Reyes National Seashore to turn into large, isolated pools of water in the summer. The pools persist throughout the dry season, providing refuge for aquatic life. What isn't normal is fewer, quickly shrinking pools. But this September, that's what we found. We also discovered that some of the pools contained high densities of the park's smallest aquatic species of concern: the California freshwater shrimp.

This summer, the San Francisco Bay Area Network’s coho and steelhead monitoring team started a two-year project to inventory aquatic species in streams across Point Reyes National Seashore and Golden Gate National Recreation Area using environmental DNA. Environmental DNA, or eDNA, is genetic material shed by organisms in the water column. By collecting particulate samples from the water, we hope to learn if species of interest are utilizing certain streams.

The second phase of a major restoration project aimed at improving habitat for salmonids in Muir Woods National Monument is underway. The San Francisco Bay Area Network’s coho and steelhead monitoring team assisted with the restoration project by removing fish from the construction areas prior to the arrival of heavy machinery.

This has been a highly productive spawner season for the salmon in the Olema and Redwood Creek watersheds. The San Francisco Bay Area Network coho and steelhead monitoring crew spotted over 140 Chinook, coho, and steelhead redds (nests) in these creeks since November. These encouraging numbers are largely due to the heavy rainfall the Bay Area received in late fall and early winter. However, two months without significant rain has sounded some alarms for our coastal streams.

This summer continues to be a challenge for the San Francisco Bay Area Network Fisheries Team and the aquatic life that inhabit our coastal streams. During our summer habitat monitoring, we found several drying pools in lower Redwood Creek in Golden Gate National Recreation Area. We also noted fish displaying signs of distress like rising to the surface for air. Our team is working closely with park managers and regulatory agencies to help save these young coho and steelhead.

Riparian ecosystems have a vital role in performing functions that are essential for coho salmon and steelhead trout and other native wildlife. The San Francisco Bay Area I&M Network salmonid monitoring team is currently performing vegetation assessments on the riparian zones within the Lagunitas Watershed. Watershed Stewards Program (WSP) corps members also organize a Watershed Awareness Volunteer Event (WAVE) to help restore the riparian corridor.

For the first time in the Coho and Steelhead Monitoring Program’s history, the monitoring crew had to stop outmigrant coho salmon smolt trapping early due to low flows. They removed the traps from both Olema and Redwood Creeks. This is just one of many indicators showing how severe the drought is this year.

Dairy and cattle ranching can contaminate streams with fecal indicator bacteria like E. coli. But changing ranching practices can dramatically reduce this risk. In 2019, Point Reyes National Seashore staff worked on a case study showing how water quality improved concurrent with grazing management practice implementation in the Olema Creek watershed. Now, they’ve published a new case study. This one looks at trends in water quality on the Point Reyes Peninsula.

For decades, coho salmon returning to spawn in urban Pacific Northwest streams have been mysteriously dying in the aftermath of large storms. Now, after a painstaking search for answers, a team of scientists have found the culprit: a previously undescribed chemical nicknamed 6PPD-quinone. Meanwhile, scientists in California’s Central Valley noticed odd behavior and high mortality among juvenile Chinook salmon in multiple hatcheries just last winter.

Point Reyes National Seashore staff, in collaboration with UC Cooperative Extension and UC Davis, recently published an article examining the long-term, on-the-ground benefits of collaborative efforts to improve grazing management and water quality in the Olema Creek watershed.