Do last winter's salmon numbers tell you anything about the fish you'll see from the Leo T. Cronin trail this December? For coho in Lagunitas Creek, the answer is almost nothing. These fish live three years, spawn once, and die. Each winter's run is its own family line. It has no tie to the run before it and every tie to the run three winters earlier.

That makes the coho coming up the creek in winter 2026–27 the children of the 2023–24 run. That run was a solid one. Marin Water's adult monitoring report counted 343 coho redds and 693 live coho that season and put the minimum escapement at 686 adults, at two spawners per redd. The parents of last winter's fish numbered about 200, according to Marin Water's October 2025 forecast. This winter's line starts from a parent run roughly three times that size.

Three generations sharing one creek

To read the creek, track three separate lines of fish, each returning every third winter.

Line C is the one people still talk about. In 2024–25, surveyors from Marin Water, the National Park Service, SPAWN, and the California Department of Fish and Wildlife logged a record 697 redds. That is more than two and a half times the long-term average of 252, and the run was twice the size of the one three years earlier. Those fish aren't due back until winter 2027–28.

Line A came back last winter, and its count turned into a puzzle. SPAWN's tracking of the year classes points to all three lines trending upward since the region came out of the 2018–19 and 2019–20 drought years. Every line is still far below its historic levels.

Why last winter was so hard to count

Marin Water's fisheries crew counts redds, the gravel nests females dig in the streambed, rather than the fish themselves. On Lagunitas Creek, muddy water and debris rule out the fish-counting cameras used on rivers like the Russian. So crews walk the creek every week from November through March. When a redd has no fish on it, they work out who built it from the evidence. Steelhead redds tend to be smaller than coho redds. Coho often leave sand in theirs, and Chinook move larger rocks.

Last winter the creek was crowded. In its February 18, 2026 field note, "CSI: Lagunitas Creek," Marin Water described a record number of Chinook salmon, a few chum and pink salmon, and unusually early steelhead, all spawning at the same time as the coho. By then crews had counted 347 redds, and 91 were still unclassified. Through the end of January, 77 redds had been confirmed as coho. Taken alone, that would rank among the smallest runs in 30 years. Surveyors also counted more adult coho than they had three years earlier, though, and the crew expected the final coho estimate to rise once the mystery redds were sorted out.

The crowding has been building for a while. In 2024–25, the Chinook run also set a record, with 124 redds and 372 live fish. That works out to an escapement estimate of 248, well above the previous record of 88 set in 2004–05. Then, in fall 2025, staff spotted an adult Chinook during a September snorkel survey and two pink salmon far upstream. Pinks had last been seen in Lagunitas Creek between 2017 and 2021. If this winter goes the same way, the big fish thrashing in the riffle could be a Chinook as easily as a coho.

The creek this generation is returning to

Line B is also coming home to a creek that has been physically rebuilt in places. Since 2019, Marin Water's Lagunitas Creek Watershed Enhancement Project has targeted 13 sites covering 4,450 linear feet of stream channel. The work adds hundreds of logs and thousands of tons of gravel to give fish cover and to create the deeper, slower pools young coho need. In fall 2025, crews used a "stone slinger," a high-speed conveyor that throws gravel from the top of the bank onto the creek bed with very little disturbance to the bank. According to the project page, work at the last Phase 1 site was scheduled for August through October 2026, and about half of the selected sites are now done.

The tributaries above Lagunitas matter more than their size suggests. San Geronimo Creek's sub-watershed covers only about 9% of the 103-square-mile Lagunitas watershed. In strong years, though, its small side streams have held up to 30% of all coho redds in the whole watershed. SPAWN's September 2026 summary of last winter's survey counted 28 coho redds across about 3.4 miles of six tributaries. Arroyo Creek led with 12, Montezuma Creek had 7, and Willis Evans Creek had no salmonids at all. SPAWN's full survey report credits fish-friendly culvert changes for the strong showings in Arroyo and Woodacre creeks and notes that other culverts are still barriers.

Larsen Creek, which produced one coho redd last winter, is the subject of its own experiment. A county project at San Geronimo Commons was funded to add 20 acre-feet of flow to Larsen Creek each year. In April 2026, the county extended the grant through March 31, 2027, to pay for a third year of flow monitoring and a final report. In SPAWN's September 2026 update, founder Todd Steiner said the latest survey "provides a reason for hope, but not complacency."

Timing your visit

Rain sets the calendar for these fish. In recent seasons, Marin Water has expected the first coho in early November and the peak of spawning after the December rains. Here's how to plan a visit around that:

1. Watch the forecast. Marin Water says viewing is best once the runoff starts to clear, usually a day or two after a significant rain. The National Park Service says one to three days after rain.
2. Plan around December and January. Marin Water calls December typically best for coho. The Park Service has traditionally named January.
3. Check the live counts. Marin Water's Spawner Dashboard holds data back to 1999 and updates during the season, and its Creek Notes field reports go out by email.
4. Get there early. Drive west on Sir Francis Drake past Woodacre, San Geronimo, Forest Knolls, and Lagunitas. Cross Shafter Bridge, about half a mile past the Lagunitas store, and turn left right away into the lot. The lot is open sunrise to sunset and fills quickly on weekends.

Once you're there, Marin Water points to the shallow water just upstream of the parking lot as one of the busiest spawning spots on the creek. Across the road, salmon can sometimes be seen jumping a small waterfall. Its etiquette list is short: stay on the road and trail, speak quietly, keep dogs leashed, and bring binoculars. Marin Water's fisheries page also states that fishing for coho is prohibited downstream of Peters Dam.

Next door, Samuel P. Taylor State Park closes Lagunitas Creek to all access and use from December 1 through June 15 to protect spawning fish and their young. Dogs aren't allowed in the creek. Bill's Trail typically closes from November through April, depending on the rain. North Creek Trail is impassable where a section of trail and a bridge washed out. The park kiosk at 415-488-0953 has current trail conditions.

For a guided walk, SPAWN's creekwalks are the local standard. Last winter's walks cost $15 per nonmember, were free for family memberships of $50 or more, and capped at 15 people. Registration was by email to [email protected]. That season's announcement went up on December 23, once the fish were running. New dates appear on SPAWN's events calendar.

Where to stop along the way

Fish watching mostly means waiting in the cold, so plan where to warm up.

• Lagunitas General Store, 7290 Sir Francis Drake Blvd., is the landmark in Marin Water's directions. It lists hours of 7 a.m. to 8 p.m. daily, with groceries, deli food, and breakfast. Its website names Patrick and Vanessa Nave Odenthal as the new owners.
• Arti Cafe, next door at 7282 Sir Francis Drake Blvd., lists hours starting at noon and running to 8:30 p.m.
• Giaco's Valley Roadhouse, 625 San Geronimo Valley Drive, lists weekday lunch, weekend brunch, and dinner.
• San Geronimo Commons, 5800 Sir Francis Drake Blvd., has parking and flat walking routes through San Geronimo and Larson Meadows, according to Marin County Parks.
• Due West Market and Tavern, 10005 Coastal Highway 1 in Olema, lists the market open 7 a.m. to 6 p.m. daily.
• Toby's Feed Barn, 11250 State Route 1 in Point Reyes Station, lists its coffee bar open daily from 6:30 a.m. to 5 p.m.
• Bar Auklet, 11180 Highway 1 in Point Reyes Station, opened just before the Fourth of July weekend in 2026. The Marin Independent Journal reported Thursday-through-Monday hours from 3 to 9 p.m.

The fish coming up Lagunitas Creek this winter descend from a parent run of at least 686 adults. When to go is still up to the next good rain and the day or two after it, when the water starts to clear below Shafter Bridge.

The San Geronimo Valley and West Marin tend to show their best side in the rainy months. If you're thinking about a home within an easy drive of that creek, the Kathleen Leonard Team would be glad to share what we know about the area, at a pace that suits you. Request a private Wine Country consultation.