North Cascades National Park Service Complex Science Days 2004

ABSTRACTS

The Fourth Annual "Science Days in the North Cascades"

June 15-16, 2004

101 Ford Hall - Skagit Valley College

"Science Days in the North Cascades" are days to celebrate the research happening in our National Park. Come hear from the scientists themselves about their discoveries.

 Little is known about the presence, distribution and relative abundance of mid-level forest carnivore populations in North Cascades, Mount Rainier, and Olympic National Parks, Washington.   Concerns over declining populations of American marten (Martes americana), fisher (Martes pennanti), wolverine (Gulo gulo) and lynx (Lynx canadensis) have prompted the need to better understand their status and biogeography.  We investigated the potential occurrence of these species using remotely triggered cameras during the winter months of February-May 2000-2003. 

Sampling has been conducted in Mount Rainier and Olympic National Parks for two winters and results will be presented in this lecture.  In North Cascades National Park, one field season has been completed and sampling areas consisted of 4 km² blocks with 2 camera stations per block, with each camera separated by one mile.  A total of 19 blocks were sampled (38 camera stations) in North Cascades during the winter of 2003-2003.  Each camera was left installed for a 28-day sampling period.  We obtained 974 photographic slides of 15 wildlife species.  The most common species was American marten (n=17 stations).  Other carnivore species detected included spotted skunk (Spilogale putorious, n=6 stations), short-tailed weasel (Mustela erminea, n=2 stations), cougar (Felis concolor, n=1station), coyote (Canis latrans, n=4 stations), bobcat (Lynx rufus, n=3 stations) and North American black bear (Ursus americanus, n= 1 station).  Incidental photos were also taken of black-tailed deer (Odocoileus hemionus), deer mouse (Peromyscus maniculatus), Northern flying squirrel (Glaucomys sabrinus ), Douglas squirrel (Tamiasciurus douglasi), Townsend chipmunk (Tamias townsendi), Steller's jay (Cyanocitta stelleri), gray jay (Perisoreus canadensis) and common raven (Corvus corax).  Sample size and safety constraints may have limited our ability to detect the more elusive and rare carnivore species such as fisher, wolverine and lynx.  Surveys are scheduled to continue during the winter of 2004.

Multi-scaled geomorphology (landform) mapping in Thunder Creek Watershed (TCW) set the stage for development of a soil distribution model.   Soil-landform relationships are strong because landforms provide information on two of five primary soils forming factors: time and parent material.  Age and sedimentology of landforms is keyed to geologic processes of erosion and deposition.  More than half of Thunder Creek watershed is classified as valley wall, while older surfaces such as fan terraces, bedrock benches, outwash terraces and glacial moraines cover less than 5% of the basin. Older landforms such as bedrock benches and glacial moraines develop spodosols on their surfaces.  Younger landforms such as debris cones, alluvial fans and floodplains typically have inceptisols.  Landforms shaped by gravitational processes such as valley walls and debris aprons are likely to have andisols and inceptisols, depending on slope stability and position in the landscape.  Landform maps and the model will form the basis for development of the first maps of soil distribution in the remainder of North Cascades, and all of Olympic and Mount Rainier National Parks.

Recently discovered alpine glacier moraines in the northern North Cascades add important new detail to our understanding of climate in the Pacific Northwest at the end of the Fraser Glaciation (ca. 14,000-10,000 ¹⁴C ybp).  Terminal moraines in five valleys span a range of climatic conditions from maritime (west) to continental (east), and define a regional advance and still-stand of 3-11km long valley glaciers.  The glaciers terminated well beyond Neoglacial (Little Ice Age) limits, but tens of kilometers upvalley from Fraser maximum advance locations.  Equilibrium Line Altitudes (ELA) for these glaciers rise from west to east at a gradient of 7m/km, paralleling modern patterns.  In contrast to late Fraser ELAs in the southern North Cascades, ELA depression at this time in the northern North Cascades was ~150m less than to the south.  This regional variability indicates that climate change at the end of the Fraser Glaciation included both depression of ablation season temperature (~2.5 ⁰C) and increases in accumulation season precipitation that were more pronounced to the south.  The timing of this advance is constrained by radiocarbon dates, volcanic ash and cosmogenic surface dating to between approximately 11,000 and 10,000 ¹⁴C ybp).

The Pliocene Hannegan Volcanics in North Cascades National Park, Washington are enclosed within contiguous ring faults of the Hannegan caldera. The modern topography developed on the intracaldera deposits extends from just north of Hannegan Peak south to Icy Peak, and from the west slopes of Ruth Mountain east to Chilliwack Pass. Prior to caldera collapse, an extensive volcanic field was present, now entirely eroded. This caldera underwent two collapse phases, venting voluminous high silica ash flows (ignimbrites) from each. The volume of material erupted is at least 60 cubic kilometers, most likely all erupted in a few days.

The first ignimbrite deposited at Hannegan caldera erupted during trapdoor –style caldera collapse. Plagioclase in this ignimbrite yielded a ⁴⁰Ar/³⁹Ar isotopic age of 3.722 ­± 0.020 million years. This ash flow is ≥900 meters thick. It is generally densely welded. Sediments were locally deposited on the surface of this early intracaldera fill. The partial ring fault formed during the first collapse propagated to the south during eruption of the second collapse phase ignimbrite. At least 900 meters of this nonwelded intracaldera unit survive erosion, overlying the earlier fill. Wall rocks breccias are intercalated as lenses and megabreccia blocks in both intracaldera ignimbrites.

Following caldera collapse, rhyolite intrusions invaded ring faults and the caldera fill. Dacite and andesite domes, dikes and lavas followed. The quartz diorite of Icy Peak and the granite of Nooksack Cirque (²⁰⁶Pb/²³⁸U ages of 3.34 ± 0.1 and 3.27 ± 0.2 million years, respectively), intruded high within the southwest margin of the caldera. These are among the youngest plutons described in the world. Erosion has since deeply incised the intracaldera fill, stripping at least 1 kilometer thickness of rock in the last 3.27 million years. The Icy Peak pluton is now exposed at the summit of Icy Peak, very nearly the highest peak within the caldera.

Hannegan caldera lies along an east-west migration of magmatic focus extending across the Chilliwack batholith to the active Mount Baker volcano.

North Cascades National Park interpretive centers do not mention the existence of volcanics. The Hannegan caldera is significant. It is superbly exposed, providing a rare opportunity to study the structure and stratigraphy of these enormously destructive volcanoes. Calderas are anomalously rare in the Cascade volcanic arc compared to other volcanic ranges around the world.

11:30 to 1:00 pm Lunch Break

Special Presentation of two Videos produced in Cooperation with Mount Vernon High School: "Bats all Around Us" and "The Intertidal Zone"

1:00 Plant Collecting Projects at the University of Washington Herbarium David Giblin, Ph.D., Collections Manager University of Washington Herbarium

 The University of Washington Herbarium is the largest herbarium in the Pacific Northwest, with over 560,00 vascular plant, bryophyte, fungal, lichen, and marine algae specimens.  For the past 120 years, amateur and professional botanists have been depositing their collections in the Herbarium for use by researchers, students, and native plant enthusiasts.  The Herbarium is currently involved in a number of regional and international plant collecting projects with several agencies and organizations that provide critical information regarding biodiversity.  This talk will provide an overview of operations at the UW Herbarium, current projects, and why herbarium collections are important.

 1:30 Archeology of the Little Beaver Watershed, North Cascades National Park

Robert R. Mierendorf, Park Archeologist North Cascades National Park Service Complex

 From the crest of the Pickett Range, Little Beaver Creek flows east for 28 km (18 miles) to its confluence with the upper Skagit River.  The watershed covers 165.8 km² (64 square miles) and is representative of many remote and untracked mountain valleys of the northern Cascade and Coast Ranges of Washington and British Columbia.  Although a small portion of the watershed has been inventoried for archeological sites, analysis of artifacts and radiocarbon age estimates reveal indigenous use for ca. 7,000 calibrated radiocarbon years.  Eighty-three percent of the total artifact assemblage is made of Hozomeen chert, 15% is made of vitrophyre from Copper Ridge source B, with the remaining portion comprised of Allenby chert from the upper Similkameen watershed, of Cache Cr. basalt from south-central British Columbia, and of non-local obsidian and chert from uncertain sources.  These data reflect two different uses of the watershed.  The first is the subsistence use of lithic materials and other locally available utilitarian resources; the second is as a travel route linking the upper Skagit River watershed with the upper Nooksack, Chilliwack, and Similkameen River watersheds.  The combined data suggest that some pre-contact indigenous groups were adapted to life and travel in high elevation terrain, revealing an aspect of Northwest Coast culture previously unacknowledged by historians, anthropologists, and most archeologists.

 2:00 Holocene paleoecology and prehistory of the North Cascades

Alecia M. Spooner : University of Washington, College of Forest Resources/ Quaternary Research Center

 Despite much work in other areas of the Pacific Northwest, we lack both a regional paleoecological perspective and a comprehensive prehistoric cultural understanding of the North Cascades.  I will discuss the research goals and preliminary results of a project scheduled over the next few years to address questions about the Holocene environmental and human prehistory of the North Cascades region.  First, local vegetation and fire history will be reconstructed using sediment records from two lakes, Thunder Lake and Ridley Lake.  Pollen, charcoal and macrofossil data from these sites, along with the results of work by Susan Prichard at Panther Potholes, will build a regional perspective of the forest and fire history.  Dated layers of volcanic ash throughout the cores will provide a chronological framework.  Lastly, the archaeological record of the North Cascades will be examined to uncover any correlation between patterns of human occupation and environmental changes.  Interdisciplinary work with specialists in archaeological faunal analysis and lithic analysis will help to answer questions of prehistoric resource consumption and the possibility of Northwest Coast migrations into the North Cascades during the Medieval Warm Period.

Wednesday June 16

9:30 Spatial and Temporal Dynamics of Fire and Vegetation Change in Thunder Creek Watershed, North Cascades National Park, Washington

Susan Prichard, Ph.D.  Fire and Environmental Research Applications Team, Pacific Wildland Fire Sciences Laboratory, USDA Forest Service, PNW Research Station, 400 N 34th St, Suite 201,Seattle, WA 98103-8600, (509) 996-8169 (home), (509) 996-2402 (office)

Little is known about the history of fire and vegetation in the North Cascade Range.  I conducted two studies in the lower Thunder Creek watershed, North Cascades National Park to evaluate past fire and forest vegetation dynamics.  The first study evaluated forest development following a series of fires c. 150 years ago.  Tree species, age and size data were sampled along altitudinal transects.  Tree species distributions and relationships with environmental factors were analyzed using multivariate and regression techniques, and forest development was evaluated from tree age and size frequency distributions.  The 7.5 km² study area supports an unusually high number of conifer species (12).  A combination of steep environmental gradients, slow rates of forest succession, frequent fire, and other disturbances maintain a diversity of species assemblages and structures.  The second study reconstructed a Holocene fire and vegetation history at a montane site from lake sediment charcoal, macrofossil and pollen records.  During the early Holocene (>10,500 to c. 7700 cal year BP) forests were likely open grown and dominated by lodgepole pine.  During the mid Holocene (c. 7700 to c. 5200 cal yr BP) lodgepole pine became uncommon and Douglas-fir and western white pine were dominant.  Shade tolerant species including western redcedar and western hemlock first appeared at the beginning of the late Holocene (5200 cal yr BP to present).  Alaska yellow cedar appeared most recently at 2000 years BP.  Fire frequency does not significantly change over millennial time scales, but fire return intervals are highly variable.  Of the 62 detected fires, 39 have a quantifiable response in the macrofossil record.  Overall, peaks in charcoal accumulation rates are associated with an initial peak followed by a drop in macrofossil accumulation rates.  Douglas-fir may be favored by fire with a strong peak in accumulation rates following fire events whereas western hemlock and subalpine fir decline following fire events.  Together, these studies demonstrate the spatial and temporal variability of fire and vegetation in mountain forests.  Climate is a major driver of vegetation change over millennial time scales, and fire and other disturbances are important agents of change at decadal to century time scales. 

10:00 Fine-Scale Variability in Growth-Climate Relationships of

Douglas-fir and Lodgepole Pine, North Cascade Range

Michael Case, College of Forest Resources, University of Washington, Seattle, WA

Information about the sensitivity to climate of Douglas-fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta) is valuable because it will allow forest managers to maximize growth and better understand how carbon sequestration may change over time. Increased understanding of tree growth responses to climatic variability will also enable us to better model and predict future ecosystem responses to climatic change.

We examined the effects of climatic variability on the growth of Douglas-fir and lodgepole pine along an altitudinal gradient in the North Cascades National Park, at annual and decadal time scales during the 20^th century. We used factor analysis to identify two common growth patterns, and correlation analysis to help determine which chronologies associated best with each factor chronology. After correlating the factor chronologies with monthly, seasonal, and annual climate variables, we identified climate-growth relationships based on elevation. Mid-elevation chronologies were negatively correlated with growing season maximum temperature and positively correlated with growing season precipitation. In contrast, high-elevation chronologies were positively correlated with annual temperatures.

Douglas-fir and lodgepole pine growth is limited by both temperature and precipitation in the North Cascades. At low to mid-elevations, growth is limited by site water balance, which controls soil moisture during the summer dry period. Temperature becomes more limiting at higher elevations, where growth is largely affected by annual temperatures and low-frequency climatic variability (e.g., PDO). Higher temperatures melt the snowpack earlier and warm soil temperatures more quickly, thereby lengthening the period of time during which growth can occur.

Projected increases in summer temperatures will likely cause greater soil moisture stress in many forested ecosystems. The potential of extended summer drought periods over decades may significantly alter spatial patterns of productivity, thus impacting carbon storage. It is likely that the abundance and productivity of both Douglas-fir and lodgepole pine will decrease on sites with shallow, excessively drained soils, south and west facing aspects, and steep slopes.

10:30 Douglas-Fir (Pseudotsuga menziesii) Growth Response To Climate Variability along Biophysical Gradients

Jeremy S. Littell, College of Forest Resources, University of Washington, Seattle, WA

David L. Peterson,  USDA Forest Service Pacific Northwest Research Station , Seattle, WA
 

Despite well developed research focusing on tree-growth / climate relationships, the uncertainty associated with climate change impacts to forest productivity in the western US is large. The goal of our work is to describe spatial and temporal patterns of Douglas-fir growth rates over the Pacific Northwestern portion of the species range. We used landscape modeling to inform sampling of tree-ring chronologies along biophysical gradients in three national parks. We employed standard dendrochronological techniques to measure and analyze tree-ring chronologies. Subsequent analyses focused on groups of chronologies from the plot, transect, watershed, and sub-regional scales in both time and frequency domains. Results indicate that climate/growth relationships are distinctly hierarchical, with coherent patterns in sensitivity to environmental variables sometimes emerging at the plot scale and other times at the watershed or ecosystem province scale. Chronology behavior is not temporally stationary. During the 20^th century, precipitation/drought variables figure prominently in growth-climate models, and in some chronologies, these relationships are linked to the Southern and Pacific Decadal Oscillations. These relationships can probably be expanded into quantitative growth models allowing linkages of productivity with predictions of future climate. The relative importance of local (aspect, elevation, site) versus regional controls (climate) on productivity varies, and predictions based on future climate scenarios will need to take this source of uncertainty into account when extrapolating responses at various scales.

11:00 Response of Western Mountain Ecosystems to Climatic Variability and Change:  The Western Mountain Initiative

David L. Peterson, Ph.D.,  Research Biologist/Professor, USDA Forest Service

Pacific Wildland Fire Sciences Laboratory

Mountain ecosystems of the western U.S. provide irreplaceable goods and services such as water, wood, biodiversity, and recreational opportunities, but their potential responses to anticipated climatic changes are poorly understood.  The overarching objective of the Western Mountain Initiative (WMI) is to understand and predict the responses – emphasizing sensitivities, thresholds, resistance, and resilience – of Western mountain ecosystems to climatic variability and change.  WMI addresses four key questions:  (1) How are climatic variability and change likely to affect disturbance regimes (particularly fire)?  (2) How are changing climate and disturbance regimes likely to affect the composition, structure, and productivity of vegetation (particularly forests)?  (3) How will climatic variability and change affect hydrologic processes in the mountainous West?  (4) Which mountain resources and ecosystems are likely to be most sensitive to future climatic change, and what are possible management responses?  WMI builds on 12 years of global change research at seven national parks through an integrated cross-site program of natural experiments in time (paleoecological and long-term studies), natural experiments in space (studies across regions and elevational gradients), and synthetic modeling.

11:30 to 1:00 pm Lunch Break

Special Presentation of two Videos produced in Cooperation with Mount Vernon High School: "Bats all Around Us" and "The Intertidal Zone"

 1:00 Whitebark Pine (Pinus albicaulis) in Subalpine Forest of the Cascade Range: a Case Study of Forest Structure with Management Recommendations  Mike Buffo, Environmental Studies Program, Bates College

Whitebark pine (Pinus albicaulis) is a subalpine tree species native to the western cordillera whose population is declining because of successional replacement by shade tolerant species, and disease caused by the exotic fungus white pine blister rust (Cronartium rubicola).  Whitebark pine is an important food source for birds and mammals in subalpine forests.  The forest structure of three sites in the Lake Chelan National Recreation Areas were described using site observations, canopy and recruitment data.  In undisturbed plots whitebark pine was found only on the rockiest substrates, while in disturbed areas whitebark pine was found in all areas.  On rocky substrates, whitebark pine forms an edaphic climax; on other substrates it is seral to subalpine fir (Abies lasiocarpa).  The Splawn Mountain site and Rainbow Ridge site can be used as models of the distribution of subalpine tree species given suspected different disturbance histories.  Future subalpine forest management must include prescribed fire, to mimic natural fire frequency, and the planting of blister rust resistant seedlings to maintain whitebark pine as a component of lower subalpine forests.

 1:30 The Effects Of Soil Amendment And Watering Regime On Germination And Establishment Of Direct-Seeded Native Plant Species Used In Sub-Alpine  Restoration at Cascade Pass

Matthew Ramsay, Center for Urban Horticulture, University of Washington, Seattle, WA

 Sub-alpine sites that have been denuded by recreational impacts may remain as bare ground even after decades of closure to continued use.  Efforts to restore these sites by establishing vegetation cover have been hampered by high seedling mortality and poor performance of surviving transplanted plants.  Direct seeding with locally collected native plant species holds great promise as an efficient method of establishing cover while preserving the genetic integrity of the local ecosystem.  However, this method has historically proven challenging. It is generally thought that poor establishment is due, in part, to high soil temperatures and low soil moisture.  This research project investigated the effects of two different soil amendments and two different watering regimes on seed germination and seedling establishment using seven native plant species at denuded sub-alpine sites at Cascade Pass in the North Cascades National Park.  Soil moisture content was measured in each of the soil treatments in order to determine the amendments’ effect on the soil’s moisture holding capacity.  In addition, seed germination and seedling growth and establishment were measured in each soil treatment.  Plant response was measured in plots that were watered 0 and 2 times during the summer in order to determine the effectiveness of this aftercare measure.  The soil seed bank was measured to estimate ambient levels of propagule inputs.  In the lab, climate controlled growth chambers were used to further test the effects of four different watering frequencies on seed germination and seedling establishment using the same set of species and seed source. 

 2:00 Distribution of native westslope cutthroat trout in the Stehekin River drainage, Washington, and hybridization with introduced rainbow trout

 Carl O. Ostberg* - Western Fisheries Research Center, Biological Resources Division, USGS, 6505 NE 65^th Street, Seattle, WA 98115, (206)-526-6282 ext. 268 (W), (206)-526 6654 (F), carl_ostberg@usgs.gov; Rusty J. Rodriguez, Western Fisheries Research Center, Biological Resources Division, USGS, 6505 NE 65^th Street, Seattle, WA 98115, rusty_rodriguez@usgs.gov

 The native westslope cutthroat trout within the Stehekin River drainage, Washington, represent a unique evolutionary lineage of westslope cutthroat trout.  Since the early 1900’s rainbow trout have been stocked within the Stehekin drainage at varying intensities from high mountain lakes and creeks within North Cascades National Park (NCNP) to the final drainage point, Lake Chelan.  The effects of these rainbow trout introductions are currently unknown.  We examined species-specific genomic and mitochondrial DNA markers from over 1,700 “trout” sampled at 18 locations within the Stehekin River drainage, NCNP, in order to determine the current distribution of westslope cutthroat trout, and also to assess hybridization between introduced rainbow and the native westslope cutthroat trout.  Our genetic analysis indicated extensive hybridization throughout the Stehekin drainage within NCNP.  Only two non-hybridized westslope cutthroat trout populations were detected and both occurred above potential migration barriers.  Hybridization appeared to vary throughout the drainage, although hybridization gradients were observed.  Migration barriers, water temperature and rainbow trout introductions likely influenced the distribution of westslope cutthroat trout, rainbow trout, and their hybrids.

2:30 Network connections: implications for salmon conservation

Peter Kiffney and Correigh Greene, Northwest Fisheries Science Center, Seattle, WA 98112

 Although headwater streams comprise 75-90% of total river kilometers in most watersheds, the importance of headwater streams for the functioning of large river systems has been largely ignored.  These headwater streams are major sources of nutrients, woody debris, and sediment, all of which can affect downstream reaches of the river network.  Recent research has shown that the physical and biological diversity at tributary junctions, the points in the network where smaller streams enter larger mainstem habitat, is higher compared to points upstream of these junctions.  However, researchers have yet to link these observations with individual, population, and community level processes.  In this research, we examined whether tributary junctions created productivity and structural gradients, and if so, whether these gradients affected abundance and growth of invertebrates and fish. Our inititial findings suggest that tributary junctions can create gradients in nutrients and fish abundance. For example, sculpin abundance and dissolved and total nutrients in mainstem habitat generally peaked around tributary junctions. This research is important because stream ecologists have primarily viewed streams as linear systems and have focused on habitat heterogeneity at small spatial scales, and not on how habitats may be linked.  In addition, this research addresses whether headwater streams are important to downstream condition and, therefore, whether headwater streams and the point where they join larger rivers are important for conservation or restoration.  Such information is critical to conserving and restoring threatened and endangered salmon stocks