Point Reyes Light - October 12, 2000
Research finds changes in Tomales Bay watershed
Among the new research aired at the State of Tomales Bay Conference last weekend was a fish count, done last year, of the final stretch of Lagunitas/Papermill Creek that until 1998 had been home for 50 summers to the Giacomini seasonal irrigation dam.
Many of the same species of fish turned up that were found in a similar count in 1983 - mainly smelt, sculpin, perch, roach, plus some stream-running steelhead and coho salmon, explained Dr. Michael McGowan of the Romburg Tiburon Center for Environmental Studies, who spoke Friday at the Inverness Yacht Club.
However, the news was in what the count didn't show. The earlier census also recorded bluegill, bass, crappie, carp and catfish - non-native species that prefer static water to flowing streams. This time around, two years after the state ordered the seasonal dam permanently removed, the only "non-native" fish to show up was American shad, an East Coast stream-runner common wherever water flows freely in the West.
Restoration works In addition, opossum shrimp - perhaps the main food source for salmon and steelhead - appears more widely dispersed over that stretch of creek than it was before. To McGowan, the changes are dramatic enough to suggest that almost any restoration work done on Lagunitas Creek is likely to improve the fish habitat.
"The lesson I drew," McGowan said this week, "is that given enough restoration, the creek could go back the way it used to be," (the huge Marin Municipal Water District dams a few miles inland notwithstanding).
The conference, the fourth of its kind since 1988 but the first in eight years, comes near the starting point for a number of related projects:
County officials are revising their main planning and land-use document, with a promised overhaul of the county's mysterious septic-system policies.
The National Park Service, having bought the Waldo Giacomini Ranch in February (and having already assumed control of 100 acres of it) wants to convert the dairy to wetlands when it gets control of the rest of the property in 2007. In effect, the wetlands will serve as a floodplain for Lagunitas Creek, which now gets channeled through the ranch. Now the creek overflows its southern levees and closes levee road when heavy rains combine with high tides.
The evolution of the Tomales Bay Watershed Council, a 24-member body that intends to produce in two years a wide range of recommendations for legislation, research, habitat restoration, and land-use practices in the 218-square mile watershed.
Fish habitat restoration projects by the National Park Service and Marin Municipal Water District.
Erosion and sediment control projects by the Point Reyes Station-based Resource Conservation District.
Nothing's horribly wrong with the bay, although the state Regional Water Quality Control Board has judged it "impaired" based on the amount of bacteria and sediment that enters with the winter run-off.
Green crabs But things do change: In 1996, huge numbers of non-native European green crabs were discovered in the bay. The crabs, which are devastating to the invertebrate population and a villain to the bay's oyster growers, have since dipped in number here (no one knows why) but for sure have taken up permanent residency.
Also, mattress-sized mounds of native cordgrass, Spartina foliosa, have appeared in just the last couple years in various mudflats around Tomales Bay. Again, no one's sure what that means. But for certain no one should want to see any of the grass' non-native cousin, Spartina alterniflora, which is now bullying its way across the shores of south San Francisco Bay and most recently, Richardson Bay.
Scientist Debra Ayres of UC Davis, who in those bays is battling the aggressive Spartina with herbicides, explained how the taller, thicker, more fecund exotic hybridizes with the shorter native and starts crowding over acre and acre of open mud, which is prime habitat for invertebrates and feeding area for shorebirds.
Invasive cordgrass "It's more than a weed, it's a disease," she said, adding that the grass can move in rafts, and may do so right out the mouth of the Golden Gate and drift north. She urged residents here to keep there eyes peeled, and offered to identify any suspicious Spartina that people turn in.
Also highlighted were efforts by the watershed's ranchers to get a handle on their winter run-off, which for the moment is the trickiest issue concerning Tomales Bay.
Ranching, of course, has kept the east shore of Tomales Bay undeveloped for the last 150 years, and several speakers at the conference acknowledged that suburban development of the watershed would be the biggest blow to its health.
Michael Mery, chairman of the Tomales Bay Watershed Council, said that the area is "blessed to have an ag community that's so responsive," and noted the efforts to improve the watershed are helped by the fact that the open space that accounts for most of it has so few owners.
Ranches & septic systems However, it seems likely that the watershed's dwindling number of dairy ranchers will be the group who, at least for now, will be asked to make the most changes in how they go about their business. (The problem of leaky or aging residential septic systems in the watershed hasn't been studied, although a local advisory board has been formed to help the county overhaul the septic code).
Studies in 1998 showed high counts of coliform bacteria at points along the eastern, agricultural shore following the first big rains of the year. That livestock operations - as opposed to wildlife or septic systems - are the main source of the bacteria was suggested again last winter, when water samples taken both near corrals and below pastures at nine of the watershed's 14 dairies showed elevated coliform concentrations.
East shore rancher Bob Giacomini noted that those tests, conducted by researcher David Lewis of UC Cooperative Extension, had the approval of ranchers, and said the dairy industry is "not closing our eyes" to the issue of manure-related contamination.
Soil aerator The rancher, who represents the 14 dairies plus two beef operations that convene as the Tomales Bay Agricultural Group, reminded the audience that because ranchers use manure to fertilize their pastures, it's "just as advantageous for us to keep nutrients on our properties" as it is for shellfish growers to keep them out of the bay.
To that end, the Marin Resource Conservation District, among other projects aimed at controlling agricultural erosion and run-off, has bought a soil aerator for ranchers to use that should allow pastures to hold on to more nutrients, explained Giacomini, who is a member of the RCD board.
The newish Tomales Bay Watershed Council over the next two years hopes to come up with specific recommendations on managing the watershed that all of the competing interest groups can live with.
Watershed coordinator Harry Seraydarian, a facilitator with US Environmental Protection who is working with the group, said that despite the obvious tug and pull between the bay's interest groups he's "more optimistic" about the success of this council that any of the others he's involved with.
The local group, which numbers 24 environmentalists, ranchers, shellfish growers, and government workers, in recent weeks hired Neysa King, who is now the coordinator of the Eel River Watershed Council, to coordinate the effort here.
King holds a master's degree in watershed management from the University of Montana. For now she will work out of an office at Bear Valley Headquarters donated by the Park Service.