Bibliography Background About KRIS
KRIS Redwood Info Links
This document contains supplemental information for contents of the KRIS Redwood Creek database. Each section below is linked to from relevant topics in the database by use of the Info Links tab.
Redwood Creek Flow and Regional Rainfall Data
Flow data in KRIS Redwood Creek come from U.S. Geologic Survey (USGS) records. Records of average daily flow are in cubic feet per second. Water years begin on October 1 of the prior calendar year. For example, the 1998 water year started on October 1, 1997. Rainfall data were acquired from the National Weather Service database and James Goodridge, former state climatologist and now consultant to the California Department of Water Resources. See the Stream Flow Background page for more information.Redwood Creek TMDL
The Total Maximum Daily Load of Sediment Redwood Creek (EPA, 1998) is the source of data for sediment related topics in KRIS Redwood Creek. Further information is available on the TMDL Background page. EPA (1998) found that the mainstem of Redwood Creek is suffering major sediment problems: "Key changes in the mainstem of Redwood Creek include (1) increases in the volume of stored sediment, (2) decreases in pool numbers and depth, (3) increases in stream width and decreases in stream depth, (4) reduced recruitment of large woody debris, (5) deposition of high levels of fine sediments on the stream bottom, and (6) reduced volumes of large woody debris." Additional findings include the following:
"Redwood Creek is particularly prone to storm-induced erosional events, and would probably experience extensive erosion under natural conditions. However, land management activities have accelerated this natural process, overwhelming the stream channel’s ability to efficiently move the delivered sediment. Land management patterns and practices have contributed to increased erosion beyond natural rates through mass wasting (landsliding) and fluvial erosion (gullying and stream bank erosion). The resultant erosion caused sediment to enter the stream, filling deep pools and depositing silt in spawning gravels. Past studies indicate that streamside landsliding and fluvial hillslope erosion may be the most important processes delivering sediment to Redwood Creek. A large proportion of observed erosion is associated with an extensive road network (7.3 mi/mi 2 ) on private lands, improperly designed and maintained roads and skid trails, and timber harvesting."
Fisheries Studies by Redwood National and State Parks
Anderson (2001) of RNSP has been using seines to sample fish using the Redwood Creek estuary since 1987. There have been consecutive summer steelhead trout surveys of Redwood Creek since 1981. The following text is excerpted form a RNSP 2000 report:
"Three adult summer steelhead (steelhead ³16.5 inches), seven ‘half-pounder’ steelhead (smaller immature sea-run steelhead returning after less than one year in the ocean), and 95 coastal cutthroat trout (O. clarkii) were observed in a mainstem survey reach from Lacks Creek to downstream of Hayes Creek in 2000. The three adults were observed within the smaller index reach (Lacks Creek to Tom McDonald Creek). The number of adult steelhead within the index reach has declined and the cohort strength of 1984 and 1985 has waned.
Westside tributaries were generally cooler than eastside tributaries; a pattern repeated in all past summer steelhead surveys. However, below the Tall Trees Grove, east and west-side tributaries were generally the same at 13 to 14°C. The 2000 year summer water temperatures are not an anomaly. Similar temperatures and trends have been recorded in past summer steelhead surveys and temperature monitoring. Water temperatures in Redwood Creek are high for salmonid fish, above the preferred temperature range reported by Reiser and Bjornn (1979) for steelhead. A California Department of Fish and Game (CDFG) funded study (Taylor and Barnhart 1997) of mortality of angler caught and released summer steelhead showed increased summer steelhead mortality with increased water temperature, a 10 percent mortality at 21°C and 35 percent at 24°C. Though only the reach downstream of Bond Creek on Redwood Creek is open to catch-and-release fishing, any incidental post-angling mortality on holding and migrating fish would be significant to the small Redwood Creek summer steelhead population. The CDFG in their 1996 Steelhead Restoration and Management Plan for California (McEwan and Jackson 1996) recommended “adjustment of angling seasons should be considered to limit catch-and-release angling to cooler water periods when hooking mortality is less”. Based on that recommendation, the mainstem of Redwood Creek should be closed to fishing during high water temperature periods. For Redwood Creek summer water temperatures to decrease, the streamside canopy will have to be reestablished, and remaining canopy protected."
Photographs Provided by Gary Todoroff
Gary Todoroff provided copyrighted photographic images to KRIS Redwood Creek. Gary maintains a studio at 618 F St in Eureka, California, 95501 707/445-8425 and can also be reached via his web site: www.northcoastphotos.com. Please contact Gary for more information about aerial photographs of Northern California.
Redwood Creek Water Temperature Data
Water temperature in the Redwood Creek basin has been measured by several sources and compiled by NCRWQCB staff. Reference values for temperature used in KRIS Redwood Creek are extensively discussed in the Temperature Background page.
Road Densities in KRIS Redwood Creek
Roads are a major source of sediment to streams with road surfaces providing chronic sources of fine sediment which can diminish salmon and steelhead spawning success. Failure of roads during major storm events can lead to large landslides which can over-whelm streams with sediment, filling pools and diminishing habitat complexity. Road densities in KRIS Redwood Creek are derived from maps provided by Redwood National Park, which were calculated from aerial photographs for different periods, and from the California Department of Forestry (CDF), which updates road coverages associated with Timber Harvest Permits (THPs). KRIS shows thresholds for roads of three miles per square miles based on Cedarholm et al (1981) and the National Marine Fisheries Service guidelines (NMFS, 1996). See documents on the topic in the KRIS Bibliography or see Roads page in KRIS Background pages for more information.Electrofishing Data for Redwood Creek
Electrofishing is generally conducted during low flow conditions from June through October and is used to sample juvenile fish. The surveys are used to gauge distribution of various species of salmonids, and in some cases calculate densities in specific areas. This technique is quantitative where block nets and repeat passes are conducted and a valid sampling method is applied. Such quantitative data has been collected by the Forest Science Project but was not available for this version of KRIS.
The California Department of Fish and Game conducted electrofishing of representative habitats in 2001 following methods described in the California Salmonid Restoration Manual (CDFG, 1998). The CDFG biological inventory involves electrofishing of representative habitats, but no use block nets, or any multiple pass procedure to allow quantitative calculations. Non detection of a species, such as coho salmon, cannot be taken as total absence. Furthermore, these inventories are highly variable with respect to documenting non game fishes and amphibians. Because of such limitations and difficulty in obtaining the data, this information is not contained in KRIS Redwood Creek
For more information see the Background page on Fish Populations.
Downstream Migrant Trapping Data
Downstream migrant traps can yield uniquely valuable information on the productivity and health of watersheds by measuring the number of juvenile fish leaving a stream and providing an opportunity to measure the size of those downstream migrants. Coho and steelhead juveniles must reach at least one year of age, and attain sufficient size, in order to survive the smolt and early ocean life stages. Large numbers of coho or steelhead yearlings (1+) indicate a potentially productive salmonid stream, while large numbers of emigrating young of the year fish (0+) can indicate habitat conditions too poor to support rearing fish. Maintaining traps and generating reliable estimates of total out migrant populations is extremely difficult.
Screw traps were operated in Middle Redwood Creek for years since 1999 by the California Department of Fish and Game and Redwood Creek Landowners Association (Sparkman, 2001). A variety of traps have also been used by the Humboldt State University Fisheries Coop, mostly used to focus on Prairie Creek and its tributaries.
For more in-depth information see also the Background page on Fish Populations.
The Department of Fish and Game conducted salmonid habitat surveys in 13 tributary streams of Redwood Creek in 2001 following methods described in the California Salmonid Restoration Manual (CDFG, 1998). CDFG reports available from these surveys were not available in time for inclusion in the KRIS Bibliography. Of the stream attributes measured, those deemed most useful for assessing conditions for supporting anadromous fish are canopy cover, embeddedness, percent pools, and pool depth. The NCWAP Ecological Management Decision Support system model for stream reach condition uses these attributes with the addition of pool shelter. Charts in KRIS illustrate the values for all five of these habitat attributes by subbasin. Habitat charts summarize data for each stream where surveys were conducted, combining data where more than one reach was surveyed. Summary data was generated from raw habitat data files using a custom query tool built by Dr. Jan Derksen in cooperation with CDFG staff.
Both the quantity and quality of pool habitat is important for productive rearing of coho salmon and yearling or older steelhead. Percent pools by length reflects habitat quantity and results from classifying unit lengths of stream as pool, flatwater, or riffle habitat. Maximum pool depth measurements are among the least subjective of any data collected in habitat surveys. Pool depth is a useful indicator of habitat quality because juvenile coho prefer pools deeper than three feet, and may require them for protection from predators. Cobble embeddedness is a visual assessment of spawning habitat quality with respect to fine sediment levels. At each pool tail where fish may spawn, an embeddedness level is assigned as category 1-4. Pool tails deemed unsuitable for spawning due to substrate size, bedrock, or other consideration are assigned a category 5. Embeddedness is a subjective method, but can be useful for assessment of spawning conditions over extensive stream networks. However, embeddedness data may be not be reliable for comparison of spawning habitat quality among streams surveyed by different observers. Canopy is measured at each habitat unit and summarized in KRIS using a weighted (unit length) average, thus illustrating the proportions of stream length covered by deciduous canopy, coniferous canopy or no canopy (open). Canopy charts provide information on potential stream warming as indicated by percent open canopy and long term prospects for large wood recruitment as indicated by percent deciduous canopy. Larger streams generally have more open canopy and deeper pools than small streams. Habitat charts thus list streams on the vertical axis by stream order, albeit imprecise and providing few categories for size ranking. Drainage area would provide a more accurate index of stream size, but this was not available.
To learn more about using fish habitat data, check the Habitat Typing Background pages.
Fine Sediment: Bulk Gravel (McNeil) Samples
The first study to describe spawning gravel conditions in Redwood Creek is Woods et al. (1979). Woods followed standard methods of the time described by McNeil and Ahnell (1964). These documents are in the KRIS Bibliography and to be linked here in subsequent version. The McNeil method involves passing material through sieves by use of water and the determination of relative fractions by measuring displacement (volume). Subsequent efforts to describe spawning gravel composition by RNP and USGS used dry-sieve techniques to measure actual percent weight (gravimetric). The dry/gravimetric method produces results not biased by the retention of different proportions of water by size class (water is increasingly retained with finer fractions of a bulk sample), results from the method are not directly compatible with TMDL thresholds and other synthesis of wet-sieve based studies. McHenry et al. (1994) compared the two methods and found "The gravimetric process described less than 50%of the fine sediment obtained by the volumetric process."
KRIS Redwood Creek uses reference values for percent fine sediment from dry-sieve sampling that utilize a conservative adjustment to be more compatible with wet-sieve/volumetric results. The Redwood Creek TMDL target of no more than 14% fine sediment less than 0.85 mm comes from a synthesis of studies using wet- sieve bulk gravel sampling. According to Shirazi and Seim (1979), the fraction of fines less than 0.85 mm from wet/volumetric methods can be adjusted by a factor of 0.739 to reflect actual gravimetric results. Applied to 14%, this correction yields a dry- sieve reference for fine sediment less than 0.85 mm of 10.3%. The U.S. EPA and California State Water Resources Control Board do not necessarily endorse the conversions.
For more information on how sediment effects fish, methods of sampling and reference values used in KRIS, see the Sediment Background page.
Cross Sections and Longitudinal Profiles in Redwood Creek
The US Geological Survey and Redwood National Park have conducted surveyed the cross section of Redwood Creek at numerous locations dating back to 1979. These sites have also been subject to inventories of surface particle size and the median particle size (D50) is presented in KRIS. Repeat surveys show how the channel may either be aggrading or degrading over time. Changes in bed elevation can be used to gauge the timing and magnitude of sediment transport (Madej 1995). See terminology and methods regarding how changes in streambed elevation over time have been summarized by RNP scientists. Longitudinal (long) profiles follow the deepest portion of the channel, known as the thalweg, over a certain reach. Longitudinal surveys have been taken in Redwood Creek but were not obtained for use in this version of KRIS Redwood Creek. See the Measuring Sediment Background page for additional information on this subject.
Suspended Sediment and Turbidity Data for Redwood Creek
Suspended Sediment data was shared with the KRIS Project for four sites in Redwood Creek. Turbidity measurements have been taken but were not available. Suspended sediment charts in KRIS show a reference value of 300 mg/l for cessation of feeding by coho salmon which comes from the following document: Canadian Department of Fisheries and Oceans, 2000, Effects of Sediment on Fish and their Habitat. See discussions in the Sediment Background page for more about this topic.
Knopp North Coast Regional Sediment Study
The proportion of a pool's residual volume filled with fine sediment is termed V* (V-star) (Hilton and Lisle, 1993). V*, D50 and other indices for measuring such impairment of stream channels were tested by Knopp (1993) at 60 northwestern California sites. Knopp measured V* in four streams in the Redwood Creek basin in 1992. Two of these sites were revisited by a Humboldt State University graduate student in 1993. Data from Knopp's testing of other indices from 60 streams are available in the KRIS source table, Knopp.dbf. Further information on V* can be found at the U.S. Forest Service Pacific Southwest Region, Redwood Sciences Laboratory web page. See the Sediment Background page to learn more or the Redwood Creek TMDL (EPA, 1988) to learn about the TMDL threshold of 0.21 V* shown on the chart.
Vegetation Size Classes for Redwood Creek Cal Water Watersheds and Sub-Basins
The vegetation data used in the KRIS Redwood Creek project were derived from Landsat multi-spectral images taken in 1994. The U.S. Forest Service Pacific Southwest Region Remote Sensing Lab, in cooperation with the California Department of Forestry, analyzed the Landsat images to formulate a California-wide electronic map layer of vegetation as part of the Northwest Forest Plan (Warbington et al., 1998). See Vegetation Types Background page for more information). Stand conditions are accurately represented at the one hectare scale by the USFS vegetation data. Data is quarried for tree size or community type in KRIS Redwood Creek. This allows quantitative assessment of vegetation types for seral stage based on tree size for geographic areas such as CalWater Planning Watersheds in KRIS. CDF FRAP change scene detection (Fisher, 2001) using 1994 and 1998 Landsat imagery allows assessment of conditions in a more recent time frame. Change scene detection themes are available in the KRIS Map ArcView and ArcExplorer projects (see Maps Background page).For use in KRIS, vegetation was simplified into the following eight size classifications based on diameter at breast height (DBH):
Giant Trees = >50" DBH
Very Large Trees = 40-49.90" DBH
Large Trees = 30-39.9" DBH
Medium/Large Trees = 20-29.9" DBH
Small/Medium Trees = 12-19.9" DBH
Small Trees = 5-11.9" DBH
Saplings = 1-4.9" DBH
Non-Forest = Non-tree coverage, such as shrubs, prairie, pastureland, urban development or bare soil.
The simpler classification used in KRIS provides an easy to understand index of watershed disturbance for use in coastal watersheds. Large components of early seral stage conditions (Saplings, Non-Forest) are often associated with recent logging disturbance. The vegetation patterns in interior basins, such as the Eel River and Klamath River watersheds, are much more complicated than in coastal ecosystems and more difficult to use to analyze changes in vegetation brought about by watershed management activities. The KRIS vegetation classification scheme can also be used for a quick analysis of riparian conditions. Ninety meter (~300 ft.) zones of riparian influence are assigned to the 1:24,000 stream layer in ArcView and only the vegetation within this zone is displayed and analyzed.
KRIS Redwood Creek Map Project
This KRIS database contains screen prints from the KRIS Redwood Creek Map project. This project assimilated data from all available sources to assist in watershed assessment. To learn more about the project and how to obtain it and/or load it on your computer see the Map Background page.
Riparian Studies in Redwood Creek
Redwood National Park and U.S. Geologic Survey staff have studied the riparian zone of Redwood Creek and found it profoundly changed as a result of past floods and timber harvest. Resulting conditions allow invasive species to colonize riparian zones. Urner and Madej (undated) describe the changes that have taken place since 1947.
Timber Harvest Data in KRIS Redwood Creek
Timber harvests for the entire Redwood Creek basin have been mapped from aerial photos by Redwood National Park. More recent timber harvests permitted by the California Department of Forestry are available in electronic form for the years 1985 and 2000. KRIS systems quantify timber harvests by Calwater Planning watersheds and compare them to a reference of 25% harvested based on Reeves et al. (1993). The latter found that simplification of stream habitats associated with over-cutting in watersheds tended to also cause a loss of salmonid species diversity.
Note about documents in KRIS
