November 1, 2000
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Until their population crash twenty-five years ago, salmon were the mainstay of a $100 million fishing industry in California. Dr. Peter Moyle, renowned fisheries professor at UC-?Davis, calls watershed deterioration the principal cause of the coastal salmonid decline, with logging and road-building as major factors. Because approximately 50 percent of coho habitat is privately owned, and 100 percent runs through private property, salmon must pass through severely impacted areas before reaching presumably more protected, often public, stretches. Such impacts can destroy entire runs. By protecting private property from the effects of irresponsible management of watershed lands, we simultaneously promote biologically viable creeks, the integrity of objective science, and the potential recovery of native salmonid populations.
According to a 1996 National Research Council report on Pacific Northwest salmonids called ?Upstream: Salmon and Society in the Pacific NW,? genetic diversity underlies the success of the species; healthy habitat sustains local variations. The report poignantly notes: ?One important reason to protect local populations is that they are locally adapted to the streams that support them. In other words, evolution has made a local breeding population better able to survive and reproduce in its home stream than in other streams. Re-establishing new populations through introductions once the local populations have been lost has proved to be extremely difficult?.
This is where we come in?those of us invested in an ecological future that not only sustains us economically but also nourishes us spiritually. This is the vision of Salmon Forever.
Why turbidity?
The North Coast Water Quality Control Board uses ?turbidity levels? as thresholds: the Basin Plan will not permit turbidity levels in streams to rise (due to sediment entry) more than 20 percent over naturally occurring background levels. Quantities of sediment that settle out and cause nuisance, such as aggradation causing flooding, are also prohibited. The Pacific Lumber (PL) Habitat Conservation Plan (HCP) recognizes turbidity ?as the single-most sensitive measure of the effects of land use on streams.?
Young salmonids are exquisitely sensitive to turbidity, which obscures their vision and hence decreases their ability to feed. They are also sensitive to suspended sediments, which cause injury in direct proportion to sediment levels and duration of exposure. Fine sediments smother the egg nests of salmonids and fill the interstices in which the young hide. Since smolt size is correlated with ocean survival of salmonids, if sediment-choked water results in smaller fish migrating to the ocean, the number of healthy adults returning to spawn likely will be reduced.
State agencies have identified increased flooding resulting from accelerated logging by PL as a major problem for Freshwater and Elk watersheds. In Freshwater last year, more than 4.5 million kilograms of suspended sediment went down the mainstem of Freshwater Creek past Salmon Forever?s sampling station equivalent to more than 220 truckloads of dry sediment. Each of the 6?7 square miles of logged watershed above the station probably contributed about 600?700 tons. Each of the three biggest storms moved more than a million kilograms past the sampling stations.
By monitoring watersheds with comparable geology, such as the Little South Fork Elk River in Headwaters Forest and Humboldt Redwoods State Park lands, we hope to be able to answer the question: how much sediment is natural? We are monitoring six watersheds in the Trinity, Eel, Van Duzen, and Humboldt Bay drainages. The information not only shows the impacts of ground-disturbing activities that have taken place but also provides an early warning system about upstream landslides, failing culverts, or other sediment sources posing threats to water quality, channel form, and in-stream habitat.
Samples are taken regularly during storms and measured in a portable turbidity monitor, and the filtered sediment is weighed in our Sunnybrae sediment lab. By measuring channel cross-sections, a 3-D picture of the channel can be used to calculate volumes. Correlations among turbidity, suspended sediment, and water discharge (volume or cubic meters/feet per second) characterize the turbidity ?signature? of a stream. Comparing these signatures among similar watersheds undergoing different intensities of land use helps to reveal the effects of upstream management activities.
Since monitoring requires multiple samples taken 24-hours, seven days a week during rainstorms, the only economically feasible strategy might be local volunteers invested in the health of their creeks. (A side effect is watershed residents? enthusiasm for turbidity monitoring as they learn the dynamics of their streams.) Alternative automatic sampling is available for remote sites and for more comprehensive data-gathering.
Salmon Forever has recruited and trained more than fifty volunteers in fifteen watersheds and analyzed more than 2,800 samples in our Sunny Brae Sediment Lab. The U.S. Forest Service Redwood Sciences Lab has provided technical assistance to analyze this data. We are developing a web site for this information. Public agencies contemplating large-scale monitoring programs are evaluating the protocols we have developed. The protocols are also undergoing final review by the U.S. EPA, and, when approved, qualify us to certify monitors under EPA standards.
Salmon Forever has joined with the Environmental Protection Information Center (EPIC) to develop the THP Watch Program. This program provides citizens with access to our data and research library for their comments on timber harvest plans submitted to CDF. Our input has modified many THPs and helps establish a useful administrative record should THPs be litigated.
We made a video with Howard Russell which presents some of the scientific evidence for the logging-related flooding in Freshwater, and residents? experiences. Our PL HCP/Sustained Yield Plan Watch program is integrated with community participation in watershed analysis, which will be coming to all of the watersheds in which PL has some ownership. In conjunction with esteemed Steelhead publisher Emelia Berol, we plan to publish a quarterly interview featuring local scientists? work relevant to salmon and watershed issues.
Salmon Forever has worked closely with local groups to emphasize the vulnerability of the North Fork Mattole River to sediment impacts, where more than 3,000 acres of virgin old-growth Douglas fir are proposed to be clearcut?1,000 within the next ten years. (The Mattole, which means ?clear water? to the Mattole Indians, is known as ?the other Headwaters? by local residents and is treasured for its beauty and wild native salmon.) We also serve as a scientific consultant to Voices of Humboldt County, a monthly publication of the Humboldt Watershed Council. The publication?s name comes from a video Salmon Forever and Humboldt Watershed Council co-produced in 1997.
Salmon Forever helps those who want to better understand the mechanisms by which impacts occur so that they can protect their home watersheds more effectively. We invite you to join our efforts. If we can help with your monitoring, watershed analysis, or THP comment needs, let us know.
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TOC for Forest & River News, Fall 2000