Abstracts

Science in the National Parks

June 23-24, 2006

Padilla Bay Interpretive Center

Mount Vernon, Washington

Friday June 23, 2006

9:00 Welcome

William F. Paleck, Superintendent, North Cascades National Park Service Complex

Key 1 Relationships between mountain climate and Douglas-fir growth patterns in the

North Cascades

9:30 Jeremy Littell, University of Washington Climate Impacts Group / Fire and Mountain Ecology Lab

Conifer species' growth and biogeography are well known to be limited by climate in mountain ecosystems. However, very little is known about the stability of growth/climate relationships in space and time. In order to put future climate change impacts to forest ecosystems into context, we need much better quantitative information on where, when, and how climate mediates tree growth. In this talk, the researcher describes results from a study of Douglas-fir tree rings in several North Cascades watersheds. Stands from 100 to 500 years old yielded chronologies that are sensitive to climate, but the nature and degree of climate sensitivity varies with the biophysical context of each stand. Common patterns emerge, however, and nearly all chronologies reflect the influence of summer precipitation and temperature during the 20th century.

Key 2 Where Ornament and Function are So Agreeably Combined: A New Look at

Consumer Choice Studies Using English Ceramic Wares at Hudson’s Bay Company, Fort Vancouver National Historic Site

10:00 Dr. Bob Cromwell, Ph.D., Fort Vancouver, National Historic Site

This paper focuses on data from over 20,000 English-manufactured ceramic ware sherds excavated from archaeological households at Fort Vancouver National Historic Site, Vancouver, Washington. The study utilizes the concept of consumer choice (Spencer Wood 1987) in a setting that effectively integrates the relationship between consumer behavior and goods consumption within a capitalist market economy. It expands this relationship, to the choices of the various socio-economic and job classifications represented by class and ethnic differentiated archaeological households. Examination of these phenomena affords a more nuanced approach to consumer choice studies than projected by Spencer Wood; in part because of the isolation of the setting and the formalized trading patterns of the Hudson’s Bay Company. In addition, the well-documented spatial definition of the various ethnic groups living and working at Fort Vancouver provides an ideal setting to explore a consumer choice perspective in relationship to the complexity of culture, class, and identity.

Key 3 Forest Carnivore Surveys in Washington’s Wilderness Parks

10:30 Patricia J. Happe, Olympic National Park; Roger Christopherson, North Cascades National Park; Jim Schaberle, Mount Rainier National Park; and Robert Kuntz, North Cascades National Park

During the winter months from 2001 through 2004, biologists at Olympic, Mount Rainier, and North Cascades national parks conduct forest carnivore surveys. We used standard methods, developed and employed elsewhere by the USFS and others, with slight modification for use in the backcountry. In each park the survey effort was conducted for 2 years, with the sampling effort rotating throughout the parks. During the study we sampled 85 4mi² blocks: 26 in Olympic National Park, 20 in Mount Rainier National Park and 39 in North Cascades National Park. Researchers obtained over 4600 animal photographs and detected 32 species, 10 of which were forest carnivores. In no park did we detect fisher, lynx, or wolverine. The most common species detected in all three parks combined were marten, spotted skunk and bobcat. Marten were detected in 66% of the sample blocks in the Cascade parks, but were undetected in Olympic National Park. Trends in species distribution relative to precipitation and elevation gradients, and the implications of the survey results for carnivore management, will be discussed.

Key 4 The Olympic Marmot: Sentinel of the High Country

11:00 Suzanne Cox Griffin, University of Montana, Missoula; Julia Witczuk, University of Montana, Missoula; Mark L. Taper, Montana State University, Bozeman; L. Scott Mills, University of Montana, Missoula

In the late 1990s, anecdotal reports that the Olympic marmot (a large ground-dwelling squirrel endemic to high-elevation meadows of Olympic National Park) was missing from historically occupied areas, combined with the precipitous decline of the closely related Vancouver Island marmot, prompted concerns that climate change, tourism, or some other force may be impacting the species. Beginning in 2002, we have investigated the extent and causes of this apparent decline. We conducted extensive surveys for marmots in both historically occupied and randomly chosen meadows, collected DNA samples (via non-invasive sampling) from marmots throughout the park, and estimated survival, reproduction and dispersal of marmots that were individually tagged (n=195) and implanted with radio-transmitters (n=78). Additionally, we used behavioral observations and experiments to determine the potential impact of tourists on marmots, and we are collecting coyote feces for DNA and diet analysis.

The Olympic marmot population appears to be declining in many areas. Marmots have disappeared from well-documented, historically occupied sites, they are absent or locally rare in parts of their range, including areas where unoccupied burrow systems attest to their recent presence, and they are declining at most of the sites where researchers have been intensively monitoring animals. Marmots do remain locally abundant in some regions and are not in immediate danger of extinction. However, both observations of marked animals and genetic evidence indicate that dispersal is rare – recolonization of abandoned sites is likely to be slow. In areas that have been intensively studied, results consistently point to the non-native coyote as the primary driver of current Olympic marmot declines. There is little evidence that direct effects of climate change, disturbance by tourists, or disease are causing declines. We cannot rule out subtle (possibly beneficial) effects of climate change or that inbreeding depression may be aggravating the decline at some sites. It is uncertain whether declines in other regions of the park are related to coyotes – researchers expect the coyote diet analysis to shed additional light on this question. It is likely that agricultural and managed timber lands outside the park serve as a source for high-elevation coyotes, since habitats with deep snow are typically marginal for the species. Low snow-pack in recent years may be further facilitating coyotes’ success in the high country.

Key 5 Black Bear Distribution Patterns in the Elwha River Watershed of Olympic National Park

11:30 Kim Sager, USGS - Forest and Rangeland Ecosystem Science Center, Olympic Field Station

For approximately 90 years two hydroelectric dams have blocked annual returns of anadromous fish to over 113 kilometers of the Elwha River in Washington’s Olympic National Park (NP). The Department of Interior now proposes to remove both dams to fully restore the Elwha River ecosystem and native anadromous fisheries. Dam removal and subsequent salmon restoration may result in altered nutrient flow dynamics throughout the watershed, with potentially profound effects on the park black bear population. To provide baseline information by which to assess the long-term ecological effects of salmon restoration on distribution patterns of bears in Olympic NP, we used Global Positioning System (GPS) radio-collar technology to describe broad-scale patterns in seasonal distribution and movements of black bears prior to dam removal. Our presentation will provide an overview of results from this research, including black bear home range size, habitat use, and patterns in elevation use. These data provide valuable baseline information for assessing the future effects of salmon restoration, and help Olympic NP biologists prepare for monitoring programs along the Elwha River.

LUNCH BREAK: 12:00 – 1:00 pm

Key 6 2002-2005 Botanical Surveys in North Cascades and Mount Rainier National Parks: What We Found and Why it Is Important

1:00 Dr. David Giblin and Ben Legler, University of Washington

Since 2002, the National Park Service has partnered with the University of Washington Herbarium to conduct vascular plant surveys at North Cascades National Park (NOCA) and Mt. Rainier National Park (MORA). We have conducted a total of 8 backcountry trips to date supported by over 30 volunteers. Nearly 1,600 specimens have been collected during these trips. Approximately 465 species, subspecies, and varieties (taxa) have been collected at NOCA since 2002, and 23% of these are new taxa for the NOCA Herbarium. At MORA, 10% of the 213 taxa collected are new additions to the herbarium there. Volunteers on these trips have not only added to the National Park Service's understanding of the vascular plant richness contained within each park's boundaries, but they have also highlighted the important contributions that citizens can make to scientific efforts in the our National Parks.

Key 7 Butterflies on the Brink: Here Today; Where Tomorrow?

1:30 Ted Thomas, U.S. Fish and Wildlife Service, Division of Listing and Recovery

The Island Marble butterfly (Euchloe ausonides insulanus) is a rare northwestern butterfly found only in San Juan County, Washington. Fourteen specimens of the subspecies were collected between 1861 and 1908. All historic collections had been observed in Canada until the subspecies was rediscovered in 1998 on San Juan Island. In 2002, the U.S. Fish and Wildlife Service was petitioned by the Xerces Society and other organizations to list the butterfly as endangered. A settlement agreement was worked out in early 2005 and included a plan to conduct extensive surveys of suitable habitat on private and public lands in north Puget Sound during the summer of 2005. The Washington Department of Fish and Wildlife, Washington Department of Natural Resources, National Park Service, Xerces Society and local volunteers partnered with the U.S. Fish and Wildlife Service to survey for butterflies and assess their habitat in 2005 and 2006. By May, 2006, more than 350 surveys were conducted at more than 140 discrete locations. Up to three populations of Island Marble butterflies may occur on Lopez and San Juan Islands. Very few butterflies are now known to exist, possibly as few as 200 to 500 adults. Numerous threats exist, including loss of habitat to invasive encroachment, residential development, road maintenance activities, and modification of habitat from periodic storms. Although habitat restoration has caused short-term adverse effects, we also anticipate a long-term positive response from this work. Support from local private and public landowners to conserve the butterfly has been encouraging. A number of conservation partners are currently developing a plan to address the long-term conservation needs of this rare butterfly.

Key 8 The Island Marble Butterfly: A Good Candidate for Restoration?

2:00 Amy Lambert, University of Washington

I will be presenting the results of my research on the population ecology and life history of the Island Marble butterfly (Euchloe ausonides insulanus Guppy and Shepard, 2000; Pyle, 2000). The Island Marble was presumed extinct until 1998, when a small population was discovered in San Juan National Historic Park (SAJH) on the southern end of San Juan Island in Washington State (Fleckenstein, 2002). Due to the Island Marbles’ small population size and potentially threatened status, several conservation organizations have petitioned the species to be listed under the Endangered Species Act (Black and Vaughan 2002). The focus of my presentation will be on egg, larvae and adult stages of development. In addition, I will address habitat requirements, distribution and dispersal behavior of the Island Marble that may contribute to passive adult recruitment in areas of native plant prairie restoration.

Key 9 Unraveling the Mysteries of the Marbled Murrelet

2:30 Dr. Martin Raphael, USDA Forest Service

The Marbled Murrelet is a seabird in the family Alcide that nests on limbs of large coniferous trees along the west coast of North America. Listed as Threatened, murrelet populations have declined with the loss, mostly from logging, of their nesting habitat. Because the murrelet’s behavior is very secretive, the Marbled Murrelet remains one of our most poorly known birds. However, we are slowly gaining knowledge about its movements, nesting habits, and population trends. Over the past 10 years, my research group has been conducting at-sea surveys for the bird throughout the San Juan Islands and Puget Sound. Population size has been fairly consistent over this time, averaging about 10,000 birds each year in Washington waters. Reproductive rates are very low and we observe only about 6 young for every 100 adults. Reproduction suffers from loss of eggs or chicks due to predators, and from periodic shortages in prey that inhibit breeding. Locally, our surveys indicate that numbers of birds in the San Juans increase dramatically from May to August but the reasons are not clear. We think this increase reflects better feeding conditions around the San Juans and may also result from birds that visit this area before dispersing further south.

Over the past three years we have captured nearly 100 murrelets and fitted them with tiny radio transmitters. We locate the birds each day by searching for their radio signals from a small aircraft outfitted with antennas and a receiver. This work has shown that murrelets cover a very large area and are able to fly long distances. For example, one of our birds was captured on June 8 near La Push. We observed that bird along the outer coast until June 26 when we found it about 100 yards off the beach near Kalaloch. The next day we found it just north of Shaw Island, a straight line distance of over 100 miles. Two birds that we captured near Port Angeles nested on Vancouver Island and regularly flew round trips of 120 miles each day to attend the nest.

Murrelets nest on the mossy limbs of large old trees, most often in large intact patches of forest. Over the past 10 years, we have developed a much better understanding of the bird’s habitat requirements and have produced maps showing the amount and location of suitable nesting habitat throughout the bird’s range in Washington, Oregon, and California. We are using this map to estimate changes in habitat over time on both federal and nonfederal lands and to relate these conditions to our population counts from our at-sea surveys. We have found that the amount of potential nesting habitat is the primary driver of at-sea population size, so that conservation and restoration of suitable habitat remain our primary means to recover this fascinating bird.

Key 10 Effects of Forecasted Climate Change on a Butterfly-Plant Interaction in North Cascades National Park

3:00 Susie Imholt, Western Washington University

Climate change can impact butterfly populations by shifting butterfly and plant phenologies relative to each other and by shortening the growing season. I studied the effects of day length, soil moisture, and stream proximity on the phenology of common red paintbrush, Castilleja miniata, a host plant of the Anicia checkerspot, Euphydryas anicia, at two subalpine meadow sites in the North Cascades National Park. I considered 14 models that include the following variable combinations to predict growing season length: 1) day length, 2) soil moisture, 3) proximity to stream, 4) soil moisture and proximity to stream, 5) day length and proximity to stream, 6) day length and soil moisture, 7) day length, soil moisture, and proximity to stream.

I used multi-model inference to determine the relative importance of day length, soil moisture, and proximity to streams. I used Akaike’s Information Criterion to select the best models from the candidate set. Day length is the most important variable, followed closely by soil moisture. The model-averaged prediction for growing season length for plants in moist soils is 9.5 days longer than for plants in dry soils. Contemporary and forecasted climate change effects on C. miniata phenology suggest that a substantial of current habitat will become unsuitable for E. anicia due to advancement and shortening of the growing season.

Key 11 Looking at Present and Past Forest Stand Structure at San Juan Island National Historical Park

3:30 Dr. Bruce Larson, University of British Columbia

In preparation for the initiation of a larger project to determine protocols for the management and monitoring of the forest vegetation at San Juan National Historic Park, we undertook to study three forest stands in detail. One stand with evidence of partial cutting, one with extensive windthrow, and one with little indication of major disturbance were chosen. We used different sampling techniques to determine in each case the nature of the disturbance and the effects on growth and changes in stand structure. For example, we were able to learn how the diameter structure of the stands changed over time. We will use some of the basic knowledge we were able to acquire to assist our efforts in the larger project. Immediate findings should be of use for the park Interpretation programme.

Saturday June 24, 2006

9:30 Welcome

William F. Paleck, Superintendent, North Cascades National Park Service Complex

Key 12 Tailed Frogs in Olympic National Park: How the Landscape Affects Gene Flow and Population Connectivity

10:00 Stephen Spear, Washington State University:

Tailed frogs, Ascaphus truei, are a stream-associated amphibian species that is especially prevalent in old-growth forests such as found in Olympic National Park. There is growing concern on how logging in unprotected areas might impact this species, but there is little data on natural population connectivity from which to base management on. Olympic National Park is an excellent study area to obtain information on natural population structure because of its large tracts of intact forest. Dispersal and gene flow in this species has always been assumed to be low because tailed frogs have low tolerances to high temperature and desiccation. However, dispersal and gene flow have rarely been measured.

In this study, we sampled tailed frogs at ten sites in three different drainages in Olympic National Park. We used microsatellite DNA markers to estimate gene flow among sites, and quantified the effect of landscape variables such as streams, solar radiation, canopy cover, and slope on gene flow. We found much higher gene flow than expected, with populations up to 10 kilometers apart connected through gene flow. There was little evidence to suggest that gene flow occurs exclusively through stream corridors, and solar radiation seemed to drive overland gene flow, as sites separated by high solar radiation had lower levels of gene flow. These results imply that the stable, old-growth forests of the Olympic Peninsula have allowed this sensitive species to have long movements away from streams, and suggests that populations may be isolated in highly fragmented areas.

Key 13 Burn Severity and Whitebark Pine (Pinus albicaulis) Regeneration in the North Cascades

10:30 Stephanie McDowell, Western Washington University

Whitebark pine (Pinus albicaulis, Engelm.) is a long-lived and slow-growing high elevation tree and an ecologically significant part of subalpine communities in the North Cascades. Cascadian whitebark pine populations in Washington are declining due to fire exclusion and an exotic fungus, white pine blister rust (Cronartium ribicola). Stephanie McDowell, a Western Washington University graduate student, conducted her Master's thesis research on the relationship between post-fire whitebark pine regeneration and burn severity. In the summer of 2005, she studied the regeneration dynamics in the Boulder Creek Burn near Juanita Lake in the North Cascades National Park and in the Tyee Complex Burn in the Wenatchee NF. She analyzes whether there are more whitebark pine seedlings on burned or unburned sites, and what level of burn severity produced the most whitebark pine seedlings. Additionally, she presents an ecological model of the relationships between environmental and biological factors that can assist in predicting the system's response to fire.

Key 14 The Ecological Consequences of Japanese Knotweed Invasion into Riparian Forests

11:00 Lauren Urgenson, University of Washington

Japanese (Polygonum cuspidatum), giant (P. sachalinense) and bohemian (P. bohemicum) knotweed are closely related congeners invading riparian areas, roadsides, and parklands throughout the United States and Europe. The rapid spread of “Japanese” knotweeds along river corridors has been of particular concern to natural resource agencies and conservation organizations. Knotweed’s invasion of riparian forests has the potential to alter critical ecological processes including stream bank stability, channel morphology, nutrient cycling, forest and understory regeneration and organic matter inputs into aquatic food webs. Currently, there is limited field research documenting the level and significance of these suspected impacts.

As a graduate student at the University of Washington, I have been conducting research that investigates two suspected impacts of knotweed’s invasion: 1) displacement of native riparian plant communities and biodiversity, and 2) alteration of the quantity, quality and decomposition of riparian leaf litter inputs into streams. The first year’s field study was conducted in 2004 at Grandy Creek, a tributary of the Skagit River densely colonized by giant knotweed, Polygonum sachalinense.

Study results indicate a negative relationship between knotweed invasion and the species richness and/or abundance of native understory herbs, shrubs, and juvenile trees. A reduction in riparian tree establishment could have detrimental and long-lasting effects on the successional trajectory of riparian forests, bank stability, hydrology, nutrient loading, micro-habitat conditions and aquatic biota of adjacent lotic systems.

In addition to the displacement of native vegetation, data suggest that knotweed invasion alters stream nutrient subsidies from riparian litterfall. Results demonstrate an average 70% reduction of native litter inputs correlated with knotweed invasion. Additionally, the C:N of senesced knotweed leaves is 52:1, a value 38% (Salix) to 58% (A. rubra) higher than dominant native species.

Analysis of nutrient re-absorbance from senescing leaves reveals that knotweed reabsorbs 75.5% of its foliar nitrogen prior to litterfall. In contrast, native species reabsorb 2.3% (A. rubra) to 33% (Salix), thus contributing a greater proportion of their nitrogen resources to riparian soils and aquatic environments through leaf litter. Litterfall from riparian vegetation comprise a primary source of nutrients and energy in forested streams and backwater channels. By altering the composition and nutritional value of allochthonous litter, knotweed invasion could have a detrimental impact on the productivity of aquatic food webs.

Key 15 Biological Soil Crusts: An Unexplored Component of the Ecology of the High Cascades

11:30 R. Gus Jespersen, University of Washington

Understanding species distribution patterns is a central problem in ecology, and one that has gained urgency with apparent shifts in the global climate regime. Traditional explanations of alpine plant distributions have focused on environmental variables, including timing of snowmelt and soil moisture. However, a growing body of recent work has demonstrated the importance of facilitation in driving alpine plant distributions. This newfound recognition of a community-level process in shaping alpine plant communities highlights the need for a more holistic assessment of species interactions and their controls in alpine ecosystems. Considering the number of national parks in the Americas with high-elevation terrain, such an effort may prove vital to forecasting how the natural and cultural resources of these areas will change over the next century.

Alpine meadows in the Pacific Northwest are mosaics of plants, bare ground, and a thin layer of lichens, mosses, and cyanobacteria, otherwise known as a biological soil “crust.” Structurally similar crusts are well-studied components of arid and arctic ecosystems worldwide; this thin layer fixes valuable inorganic nitrogen, stabilizes highly erodable soils, and serves as a reservoir for scarce soil moisture. Recent adventures in China, Nepal, and Washington State suggest that these crusts are ubiquitous to alpine ecosystems worldwide. I propose to investigate the ecological functions of alpine biological soil crusts in Olympic National Park via a series of

manipulative field experiments and descriptive surveys. I will transplant crusts surrounding adult and established seedling plants to adjacent plants living on uncrusted substrates and follow the growth response of the plants over the course of two years. To elicit mechanistic pathways, I will measure the effect of these treatments on the subterranean physical and chemical environment. Finally, to interpret these experimental results at the landscape scale, I will describe crust composition and vegetation associations in this alpine basin. This work is a necessary subsidy to our understanding of alpine ecosystems throughout western North America, and a missing piece of the alpine plant distribution puzzle.

LUNCH BREAK: 12:00 – 1:00 pm

Key 16 Ecological Investigations of the Elwha River: Setting the Stage for Long-Term Monitoring of Fisheries and Ecosystem Recovery

1:00

In 2009, Olympic National Park will begin a large-scale fisheries and ecosystem restoration of the Elwha River. Once a prolific salmon producing river, migration past the lower 4.9 miles of river is blocked by 2 of the largest dams ever set for removal. These dams have stood for over 90 years, blocking access to 70 miles of mainstem, floodplain, and tributary spawning and rearing habitat. The dams have altered natural cycles of sediment transport and large wood recruitment in the reaches between and below the dams, which has had a dramatic effect on habitat for many species, including salmon. Full restoration of the Elwha River is expected to include runs of all 5 species of Pacific salmon, as well as lamprey, coastal cutthroat, and char. In order to learn as much as possible about the process of ecosystem recovery through dam removal, especially in regards to the role of salmon, we have begun collecting baseline data of the aquatic ecosystem throughout the Elwha basin. Our goal is to describe existing, habitat-specific patterns of microbial, algal, macroinvertebrate, and fish communities. We are also collecting water samples to determine levels of dissolved nutrients and stable isotopes to develop baseline levels of "marine-derived" nutrients. These data are necessary to describe existing conditions and will allow comparisons in both the short- and long-term. Our presentation will include an introduction to the scientific questions being asked, the methods employed, and preliminary results.

Key 17 Sources and Dynamics of Large Wood in the Queets River

1:30 Josh Latterell, University of Washington

Large wood supports biocomplexity and creates ecologically valuable habitats in alluvial rivers but has declined to critically low levels in many rivers. Some of the most important pieces come from the erosion of mature forests containing large logs, which play an irreplaceable role as the foundational structural members of logjams. Conservation and restoration of large logs and the habitats they create relies, in part, on understanding their sources and dynamics in reference systems. We quantified the delivery of large logs (? 1 m diameter) to the channel through bank erosion and their cycling within the channel and floodplain over time (1939-2002) and space in the Queets River. Our results show that 76% of large logs annually recruited to the channel by bank erosion originate from mature fluvial terraces. The remaining 24% are recaptured from the floodplain stockpile, consisting of abandoned and/or buried logs previously deposited by the river and incorporated into developing forests. Input rates increase with the size of the annual peak flows, and channel meandering is a particularly important driver, cutting laterally up to 0.5 km through wide swaths of forest.

We estimate 95% of the logs captured by the river from 1939-2002 originated within 265 m of the initial channel margin. Input rates vary widely among locations; wood 'hotspots' supply 38% of the large logs but compose only 10% of the valley length. These often occur at the downstream cutbanks of newly-forming meanders fringed by mature forests. Tagging studies and photo interpretations indicate that approximately 42% of large logs remain stable for ?10 y after they initiate a logjam, but once incorporated by riparian forests, they become relatively stable. We estimate large conifer logs have a 50% probability of occupying ? 3 locations and traveling ?1.5 km before disintegrating, but 10% will travel ?12 km and occupy ?7 locations. The ongoing rearrangement of large logs supports a shifting mosaic of habitats in aquatic and riparian environments. Wood recruitment and dynamics in the Queets River reflect, in part, the proximity of mature forests, patterns of channel change, and variation in flood magnitude, providing a model system for floodplain river conservation in the Pacific coastal ecoregion.

Key 18 Monitoring Streamflow in Cascade Mountain Headwaters: Why is the Hydrograph Useful and What Can It Tell Us (Or Not)?

2:00 Anne Weekes, Ph.D. Candidate, University of Washington

Streamflow gauges were installed in comparable headwater catchments in North Cascades National Park and Mount Rainier National Park to investigate potential differences in patterns of response. Installed as part of a park-wide monitoring program, analysis of the gauge data has shown that aquatic habitats may vary considerably between seemingly analogous streams based on differences in streamflow regime. Some of these differences suggest that earlier assumptions about the behavior of mountain streams were too generalized to be useful.

For example, it was commonly assumed that little groundwater storage occurs in mountain basins. Particularly in mountains composed of the crystalline bedrock found in many parts of the North Cascades, hydrologists were confident that the groundwater contribution was slight. The combination of steep slopes, thin soils, impermeable bedrock and rapid response to rain and rain on snow events led scientists to assume that little water was stored within the basins themselves. This “Teflon Basin” theory was difficult to test in remote mountain drainages for a variety of reasons, not least of which were the inability to “see” below the surface in remote wilderness areas.

Streamflow gauges placed in adjoining headwater drainages demonstrate that some basins will show rapid response to storm events while others will behave like traditional groundwater systems with a muted response to precipitation events and comparatively high flows during dry periods. The story does not stop there; results from the use of stable isotopes to determine the age of water have displayed marked differences in the residence times of water in adjoining basins. As precipitation falls on headwater basins with larger storage capacities, the “old” stored water is displaced by the new water so that water flowing downstream is not always dominated by runoff from the current storm.

Streamflow hydrographs can also reveal other differences and similarities in the response patterns of these headwater catchments. In conjunction with potential changes in climate patterns in the coming years, these gauge records will provide important insight into current conditions, especially when compared to past years of record.

Key 19 Effects of Thinning and Prescribed Burning in Forest Fuel Reduction Areas of the Stehekin Valley

2:30 Karen Kopper, North Cascades National Park

The fire management team at the North Cascades National Park utilizes thinning and prescribed fire to accomplish its goal of hazard fuel reduction in the Stehekin Valley. Thirty-four forest plots have been established within the treatment units in order to monitor the effects of the treatments on tree density and basal area, native ground-cover and fuel loading. Preliminary results from the monitoring suggest that a combination of thinning followed by prescribed burning may yield a more desirable outcome than using either treatment exclusively. Selective reduction of the canopy trees can be successfully achieved through mechanical means, whereas prescribed fire is needed to consume the additional fuel concentrations in the thinned areas, and to stimulate new growth in understory vegetation.