Lagunitas watershed gives hope to the species

By November 26, 2008Uncategorized

Lagunitas watershed, which holds the largest remaining Central Californian Coast coho salmon population in the state, was one of the few bright spots in a report released last week that found 65 percent of the state’s native steelhead, coho and trout species will be extinct in the next 100 years.

The Central Coast coho are among 20 species in California that are in urgent need of help, according to the study’s authors, Dr. Peter B. Moyle, conservation biologist from U.C. Davis, Dr. Joshua Israel and Sabra Purdy.

Titled, “SOS: California’s native fish crisis – status of and solutions for restoring our vital salmon, steelhead and trout populations.” the report was commissioned by California Trout, a wild fisheries conservation group that says the state’s native salmonoids are in unprecedented decline and are teetering towards the brink of extinction. The report gives the Central Coast coho, a federally-listed endangered species, the lowest score before extinction on a scale from zero (extinct) to five (expanding populations). The low score means that the Central Coast coho could be extinct within the next 50 years.

It’s a bleak outlook, except for the fish that return to Papermill Creek. “With the possible exception of the small population in the Lagunitas Creek watershed, Central California Coast coho are on the verge of extinction,” the authors said. “The most important factor for this species’ survival is to protect to coastal streams and enhance watersheds that have potential to support coho salmon.”

SPAWN – pariah, piranha Although at times controversial in its fierce stance to protect the rights of salmonoids over the slightest development project along the watershed in the San Geronimo Valley, Salmon Protection and Watershed Network’s monitoring, restoration and community outreach programs might have paid off for the coho salmon and the survivability of the species. The environmental group, which has planted thousands of native plants along the watershed and monitors the numbers of salmon from Inkwells to the San Geronimo Creek’s headwaters in Woodacre, can take a lot of the hardearned credit for the exceptional numbers of coho that spawn in the watershed. “This is a good example of a watershed group that has really helped the fish through monitoring, publicizing the plight of the fish, advocacy and restoration projects,” said Dr. Moyle, writing in the report that supports community-based projects which focus on healthy watersheds. “[SPAWN’s] actions have definitely helped coho in Lagunitas Creek and will be even more important in the future,” he said.

The SPAWN’s point of view is clear. They are against any further development that might interfere with the salmon and steelhead populations. The group has spearheaded a Salmon Enhancement Plan with the county and a two-year moratorium for development in the San Geronimo Valley. “Over 10 years of community-based restoration projects by SPAWN and others has resulted in the current status of the largest, southernmost population of wild coho,” SPAWN Watershed Biologist Chris Pincetich said in reaction to the report.

SPAWN estimates that the Lagunitas watershed represents up to 30 percent of the state’s wild Central Coast coho population in a population that has declined by 90 percent statewide. Moyle goes even further in his estimates for coho in Marin County creeks, including fish, which were reintroduced from hatcheries. “There are so few fish left that there are really no reliable overall numbers,” Moyle said of the overall population and the funding to count them. “If we assume an average of 500 to 600 fish a year come up the six streams in Marin County and that Central Californian Coho totals average 1000 to 1200 fish per year, then Marin County (mostly Lagunitas Creek) supports about 50 percent of the Central California coho and about 10 percent of all coho statewide. “Eric Ettlinger, aquatic biologist for the Marin Municipal Water District who monitors Lagunitas and San Geronimo Creeks, said that Lagunitas Creek is the most important stream on the Central California Coast with the largest population. “The populations south of us probably won’t survive,” he said referring to rising temperatures from climate change and the small populations found in Santa Cruz County. “The water is just to warm.” Habitat preservation key Coho salmon and steelhead need wooded habitat, cool water and shaded pools to spawn and survive. The immature fish are particularity vulnerable to temperature. They also need shelter from rains that could flush the fish downstream and kill them. Although the steelhead population is listed as threatened and could go extinct in the next 100 years, according to the report, the coho are much more susceptible to rising temperatures and less resilient to such changes.

As sediment plays a primary role in covering the small pebbles and organic matter the female uses to build her nest to lay her eggs, development along the creeksides is a primary enemy to the fishery, the authors said, but so is climate change. “Global warming has perhaps played the most significant role in the alarming drop in numbers for many of these fish, as salmonoids are particularly sensitive to changes in water temperature, and rapidly shifting ocean conditions affect those that migrate between rivers and the ocean.” Other factors certainly contribute to the survival of the local species in the watershed. Notwithstanding the health of the ocean which is in flux, the restoration of the Giacomini Wetlands in Point Reyes National Seashore also provides further shelter for the salmon before the rains and the spawning season in December as well as a refuge in the spring when the population moves toward the open ocean, said Mike Reichmuth, fisheries biologist for the National Seashore.

Insecticides and Bush

In a related development, the National Marine Fisheries Service (NMFS) released a “biological opinion” last week setting a plan for protecting Pacific salmon and steelhead from three pesticides. The authors concluded that the insecticides chlorpyrifos, diazinon, and malathion would “likely destroy or adversely modify critical habitat for 25 of 26 listed Pacific salmonids with designated critical habitat,” including those of steelhead and coho. The agency lists actions necessary to keep the pesticides out of water and to protect salmon populations on the entire west coast.

But nationally, the Endangered Species Act itself could be in peril. The Bush Administration this week is making changes to the act that would exempt federal agencies from taking climate change into account when assessing risks to endangered species like the coho or even the polar bear. The new regulations will eliminate the requirement of an independent scientific review by either the U.S. Fish and Wildlife Service or the National Oceanic and Atmospheric Administration of any federal project that could affect a threatened or endangered species. The new regulation proposed by the Bush Administration will reverse 35 years of protocol that requires an environmental review.

As for the report on California’s native fish populations and the local coho and steelhead, Moyle said he and his researchers were surprised by the number of species likely to become extinct. “Things are bad but there is still tremendous potential to keep the species going,” he said. “Making this happen will not be easy.”