Conference Abstracts and Presentations

* invited presentation


Talk*
PREDICTED MULTI-TROPHIC LEVEL RESPONSES OF MONO LAKE TO CLIMATE CHANGE AND WATER MANAGEMENT

JELLISON, ROBERT
Marine Science Institute, University of California, Santa Barbara, CA 93106-6150

The predicted responses of lakes to climate change are highly lake-specific and depend on the complex interplay
between hydrology, morphometry, mixing, nutrient cycling, and biotic interactions within a lake. Salt lakes are
particularly sensitive to climate change as changes in their hydrologic budgets determine their size, salinity, and
biotic communities. However, water diversions have dominated changes in the water balances of most large salt lakes
throughout the 20th century. At Mono Lake, past diversions have lowered the surface elevation to well below its
natural climatic equilibrium and now the effects of decreasing salinity associated with the current policy of restricting
diversions until an elevation of 6391 ft is reached are predicted to be much larger than any associated with climate
change.

Limnological monitoring from 1979-2007 has revealed a striking multi-trophic level response to variation in salinity and
temperature. Adult abundance of the spring generation (May-June) is negatively correlated with salinity and positively
correlated with March water temperature and phytoplankton abundance. However, adult abundance of the summer
and autumn populations are inversely correlated with May-June ovoviviparous reproduction due to a pronounced larval
bottleneck experienced by early instars. Thus, the seasonal abundance of Artemia has shifted to earlier in the year
(slope, 1.5 days/yr; r2, 0.46) over the 28-year record of varying but generally decreasing salinities. This seasonal shift
has benefited breeding California Gulls at the expense of autumn staging and migrating Eared Grebes.
Given the management policy of maintaining a relatively constant surface elevation once lake levels reach 6391 ft,
the impact of climate change on the lake’s water budget would be mitigated. However, predicted warming and
increased spring water temperatures will likely cause a further shift of the seasonal abundance of Artemia to earlier
in the year.

 

Talk
OBSERVED CLIMATE-SNOWPACK RELATIONSHIPS IN CALIFORNIA AND THEIR IMPLICATIONS FOR THE FUTURE

KAPNICK, SARAH; HALL, ALEX
University of California, Los Angeles 90095-1565

A study of the California’s Sierra snowpack has been conducted using snow station observations and modeled surface
temperature data. First of the month snow water equivalent measurements were combined from two datasets to
provide sufficient data for statistical analysis of the evolution of the snowpack during the snow season from 1930 to
2007. The temporal centroid of snow water equivalent (“SCD”) is used to assess variability in the timing and
magnitude of snow accumulation and melt, from February 1st to May 1st. Since 1930, there has been a trend towards
earlier SCD by 0.4 days per decade. Since 1948, regional March temperatures, using the NCEP Reanalysis 1 surface
temperature dataset, have increased at a rate of 0.4°C per decade. The trend in SCD can be explained by its
sensitivity to local March temperatures. The SCD is shown to shift earlier in the season by 1.3 days per 1°C increase in
March temperatures. Given modeled predictions of future temperature in California, the peak date may shift by more
than a week by the end of this century.

 

Talk
WHO'S AFRAID OF THE SNOWBALL EARTH: EARTH'S FUTURE CLIMATE FROM THE DEEP PAST

KENNEDY, MARTIN
University of California, Riverside, CA

no abstract received

 

Talk*
CHEMISTRY, DISCHARGE, AND NUTRIENT CONTRIBUTION OF TWO ROCK GLACIERS IN THE SOUTHERN SIERRA NEVADA MOUNTAINS OF CALIFORNIA

KIRCHNER, PETER; RICE ROBERT; LIU, FENGJING
Sierra Nevada Research Institute, University of California at Merced, Merced, CA

Rock glaciers are a contributor to base flow and a source of nutrients in riparian habitats but we presently have little
understanding of the magnitude of this contribution or their biogeochemical behavior. In this study we investigate
two rock glaciers located in the Southern Sierra Nevada. Water samples were collected in time series from the
summer of 2006 to 2008 at the outlet of rock glaciers in the Big Pine Creek and Rock Creek watersheds. Stream stage
and conductivity was monitored at the outlet of both sites. Water samples were analyzed for conductivity, major
ions, stable isotopes (d18O and dD), and 36Cl. Results at the Big Pine rock glacier show a distinct shift from snow to
subsurface dominated flows as conductivity increased from 7µs to 62µs and dD increased from -125‰ to -110‰,
indicating subsurface flows originated from the melting ice-core of the rock glacier. An earlier shift to subsurface
dominated stream flow in 2007 corresponded with a lower than normal snow pack. Results from the Rock Creek site
showed snow-melt water fractionation values of dD and conductivity values <10µs indicating little or no melting ice
contributed to the sampled discharge. Nitrate and sulfate concentrations generally increased seasonally from 5.3µeq
L-1 to 20.5µeq L-1 for nitrate and 3.2µeq L-1 to160.8µeq L-1 for sulfate indicating the existence of microbial
communities within the rock glaciers. However, these nitrate values are significantly lower than results from rock
glaciers in the Rocky Mountains where atmospheric contributions to nitrate formation are higher. Concentrations of
36Cl ranged from 1.5 x106 atoms L-1 to 6.9 x107 atoms L-1 suggesting the presence of biogeochemical storage sinks or
the contribution of bomb pulse fallout in samples with a large subsurface component.

 

Talk*
MODELING ALTERNATIVE ALPINE VEGETATION STATES RESULTING FROM CLIMATIC SHIFTS AND FEEDBACKS FROM PLANT-ANIMAL INTERACTIONS

KLINGER, ROB (1); OSTOJA, STEVEN (1); BROOKS, MATT (2)
(1) USGS-BRD. Yosemite Field Station-Bishop Office, 568 Central Avenue, Bishop, California 93514, (2)USGS-BRD.
Yosemite Field Station-El Portal Office

Studies of climate change effects on animals and plants in alpine ecosystems have been focused principally on
pattern; i.e., expected shifts in species ranges and abundance. However, the functional consequences to alpine
ecosystems from changes in species distributions have not been addressed in a systematic or integrated way. Alpine
animals, particularly small and medium-sized mammal species such as pikas, marmots, and ground squirrels, are
known to play extremely important roles as herbivores and granivores in alpine ecosystems. While it is widely
assumed that there will be an inevitable, climatically driven transition of alpine meadows to tree/shrub communities,
interactions between climatic shifts, abundance of mammal species with different life-history traits, and biotic
processes such as herbivory, granivory, and competition could lead to multiple pathways resulting in alternative
vegetation states. We have developed a state-transition model representing eight alternative pathways leading to
four alpine vegetation types: conifer forests (whitebark pine) that have either a grassy or woody understory, dry
alpine meadows, and wet meadows. The pathways include ones characterized by strong physical forces (temperature
and precipitation regimes), and those characterized by strong biotic interactions (seed predation, seed dispersal,
herbivory, and competition). We hypothesize that pathways characterized by strong physical factors would
deterministically result in just one or two distinct alpine vegetation types, while those characterized by strong species
interactions would likely result in a mosaic pattern of many alternative vegetation types. Although largely conceptual
at this point, the model explicitly allows the development of alternative hypotheses related to direct and indirect
effects of climatic shifts on alpine ecosystems. Moreover, the various states and transitions of the model can be
quantified, which would facilitate a more mechanistic understanding of the relationship between climatic shifts,
species additions and deletions, plant-animal interactions, and the stability of alpine vegetation communities.

 

Talk
REGION-WIDE DENSITY ESTIMATES AND HABITAT ASSOCIATIONS OF ALPINE MAMMAL ASSEMBLAGES IN THE SIERRA NEVADA AND WHITE MOUNTAINS: IMPLICATIONS FOR MODELING SPECIES DISTRIBUTIONS AND POPULATION PERSISTENCE UNDER A CHANGING CLIMATE SCENARIO

KLINGER, ROB; CHASE, JENNIFER; LEE, STEVEN R.; SWINGER, LINDSAY; BRYANT, JESSICA; LEE, ROBYN; OSTOJA, STEVEN
USGS-BRD. Yosemite Field Station-Bishop Office, 568 Central Avenue, Bishop, California 93514

While it is widely believed that climate shifts will result in contractions in range and/or reduced abundance of many
alpine mammal species in the Sierra Nevada and White Mountain ranges, lack of range wide data on their distribution
and abundance impedes an objective evaluation of the validity of this belief. We have implemented a ten-year,
multi-scale study of the population dynamics and demography of small alpine mammals in the Sierra Nevada and
White Mountains, the main goal being a better mechanistic understanding of the relative influence of direct and
indirect effects of climatic shifts on their distribution and abundance. Here we present the first year of data (June-
September 2008) on density and habitat associations of the yellow-bellied marmot, Belding’s ground squirrel, goldenmantled
ground squirrel, and American pika. Rangewide and regional density and habitat associations were estimated
from a total of 1206 observations recorded on 40 variable-distance line transect samples totaling 452 km. Estimates
of the probability of local occupancy and detection were obtained from 25 variable-distance points visited 6 times
between June and August 2008. Densities of the yellow-bellied marmot, pika, and golden-mantled ground squirrel in
the White Mountains were similar to those in the Sierra Nevada. Marmot, pika, and golden-mantled ground squirrel
densities were generally greater in the southern than the central and northern Sierra Nevada, while density of
Belding’s ground squirrel was greater in the northern than central and southern part of the range. However, estimates
of density based on geographic stratification were three times more variable than estimates stratified by relativedensity. Detection probabilities for all four species were relatively high (0.69-0.83), but occupancy rates varied from
less than 0.56 for the pika and Belding’s ground squirrel to 0.88 for the golden-mantled ground squirrel. All four
species showed distinct preferences among vegetation types, with the pika being most specialized and the goldenmantled
ground squirrel the most general. Although interpretation of data from just a single year must be made
cautiously, collectively the results suggest models of alpine mammal species distributions must include variables
representing habitat structure and not simply climate. More generally, these data indicate that indirect effects from
climate shifts may have as strong or stronger effects on alpine mammal distributions as direct effects, and these
effects may not necessarily be uniformly negative for all species. We hypothesize that responses of alpine mammals
to climate shifts may actually be very heterogeneous, with range shifts or changes in abundance occurring in some
areas but not others and to a greater degree for some species than others.

 

Talk*
INTERACTION OF AN INTRODUCED PREDATOR WITH FUTURE EFFECTS OF CLIMATE CHANGE IN THE RECRUITMENT DYNAMICS OF THE IMPERILED SIERRA NEVADA YELLOW-LEGGED FROG (RANA SIERRAE)

LACAN, IGOR (1); MATTHEWS, KATHLEEN (2); FELDMAN, KRISHNA (2)
(1) University of California, Berkeley, Department of Environmental Science, Policy and Management, Berkeley, CA
94720, (2) USDA Forest Service, Pacific Southwest Research Station, Albany, CA 94701

Annual variation in snowpack (from 20 to 200% of average) and summer rainfall cause large fluctuations in volume of
small lakes in the higher elevation (>3000 m) Sierra Nevada Mountains, which are important habitat for the imperiled
Sierra Nevada Yellow-legged Frog, Rana sierrae. Climate change (global warming) is predicted to increase these
fluctuations, potentially leading to more frequent summer drying of the shallow, fishless ponds where most R. sierrae
breeding and larval development (requiring =3 years) occurs today. This study explored the interaction between
water availability and the abundance and recruitment of R. sierrae in Dusy Basin, Kings Canyon National Park,
California, USA. We mapped the Dusy Basin lakes with GPS, and calculated water volumes in a low-snowpack year
(2002) and a high-snowpack year (2003), and counted R. sierrae. The lakes that dried up in 2002 were repopulated by
adult frogs in 2003, without any recruitment of metamorphosed frogs from previous year’s tadpoles. The lakes that
had retained water, even with notable water-volume decreases (-60%), showed tadpole-to-subadult recruitment in the
following year (2003). Analogous results are obtained using data for years 1997 – 2006: significantly greater
abundance of metamorphs in permanently wet lakes than in lakes that had dried even once during the ten years.
Similarly, those lakes that had retained water during any two preceding years had significantly more metamorphs than
lakes that had dried up during that period. Our results suggest that any increase in drying of small ponds will severely
reduce frog recruitment. Combined with the invasive fish that prevent frog breeding in larger lakes, it may lead to
the extinction of local frog populations.

 

Plenary Talk*
ECOSYSTEM CONSEQUENCES OF PRECIPITATION CHANGE IN EASTERN CALIFORNIA

LOIK, MICHAEL E.
University of California at Santa Cruz, Santa Cruz, CA 95064

Snowfall is the dominant hydrologic input for high elevations and latitudes of the arid- and semi-arid western United
States. Sierra Nevada snowpack provides numerous important services for California, but is vulnerable to
anthropogenic forcing of the coupled ocean-atmosphere system. Fundamental ecological models predict migrations of
species to higher elevations under a warmer climate, but how will changes in snow depth and melt timing affect soil
and plant water relations, growth, and recruitment for dominant shrubs and trees at the ecotone between the Sierra
Nevada conifer forest and Great Basin Desert shrubland? And, how do these processes affect carbon storage and fire
fuel accumulation within these systems? To address these questions, our experiments utilize large-scale, long-term
roadside snow fences to manipulate snow depth and melt timing. These treatments affect short-term soil moisture
pulses, and over the long-term, they impacted cover or biomass of Achnatherum thurberianum, Elymus elemoides,
and Purshia tridentata. Growth of adult Pinus jeffreyi was sensitive to snow depth, and seedling recruitment was
higher under the Nitrogen-fixing shrub Pu. tridentata. By contrast, Pinus contorta growth was reduced by both
increases and decreases in snow. Root and litter inputs, as well as soil carbon and nitrogen content, were different
within intershrub and shrub canopy microsites, and across snow depth treatments. Results indicate complex
feedbacks between snow depth, soil water inputs, physiological processes, and population patterns at multiple spatial
and temporal scales, portending trade-offs between future ecosystem carbon storage and fire fuel accumulation.

 


Plenary Talk*
MOUNTAIN HYDROCLIMATOLOGY AT ECOSYSTEM SCALES: WHAT DO WE NEED TO KNOW?

LUNDQUIST, JESSICA D. (1); LOTT, FRED (1, 2)
(1) Civil and Environmental Engineering, University of Washington, Seattle, WA 98195, (2) Northwest Hydraulic
Consultants, Seattle, WA 98188

In the high desert of the Eastern Sierra, the structure and composition of mountain ecosystems depends critically on
when snow cover disappears and on when water availability becomes limiting. Most assessments of climate change
demonstrate a strong understanding of the former, e.g., warmer temperatures and earlier snow melt, but a weak
understanding of the latter. To accurately model the spatial patterns and timing of late-summer streamflow and
water availability, we must understand 1) the spatial distribution of snowfall and resulting snowpack heterogeneity; 2)
the frequency, locations, and intensity of summer precipitation, mainly thunderstorms; and 3) how vegetation
modulates evapotranspiration in response to increasing vapor deficits and decreasing soil moisture. Here, we review
current modeling approaches of varying complexity and present innovative monitoring techniques to learn more about
these processes.

 

Talk*
MEADOW GROUNDWATER STORAGE IN THE UPPER SAN JOAQUIN WATERSHED, WITH A FOCUS IN THE ANSEL ADAMS AND JOHN MUIR WILDERNESSES

LUTRICK, ERIN (1); HILL, BARRY (2); JACKSON, BENJAMIN (3)
(1) Inyo National Forest, Bishop, California; (2) Forest Service Pacific Southwest Regional Office; (3) UC Berkeley
school of Environmental Design

With climate change and steadily increasing population, appropriate management of water from California’s Sierra
Nevada Mountains will be a challenge. With less snowfall and earlier melting, the snowpack is no longer storing winter
water as long into the dry summer months, and groundwater storage in upper elevations of the Sierras may become
relatively more important. However, there is little data about groundwater storage in the Wilderness, headwater
areas of the Sierra Nevada. To help improve knowledge of shallow groundwater storage, we instrumented three
meadows within the Ansel Adams and John Muir Wilderness, and one adjacent to the Wilderness in the Upper San
Joaquin River Watershed, to better understand meadow groundwater storage, streamflow within meadows, and the
effects of meadow degradation on meadow groundwater storage and downstream flow. This work is being completed
as a part of a CalFed funded Upper San Joaquin Watershed Assessment. We installed eight to eleven groundwater
monitoring wells and/or piezometers in each of three meadows; Johnston, Purple, Tully Hole, and Agnew Meadows.
Preliminary results from summer 2008 will be presented, as well as challenges in completing the work. Challenges
included getting permission from land managers to install temporary structures in Wilderness, as well as access issues,
and equipment limitations for Wilderness use.

 

Poster
DESCRIBING FORESTS IN YOSEMITE NATIONAL PARK WITH ACTUAL EVAPOTRANSPIRATION AND DEFICIT

LUTZ, JAMES A. (1); VAN WAGTENDONK, JAN W. (2); FRANKLIN, JERRY F. (1)
(1) College of Forest Resources, University of Washington, Seattle, WA 98195-2100, (2) USGS Western Ecological
Research Center, Yosemite Field Station, El Portal, California, 95318

Models of water relations have been used to explain tree species distribution, but these models generally assume flat
terrain and uniform soil water storage making them less useful in mountainous terrain. We extended a Thornthwaitetype
model by considering differences in water demand based on the local slope and aspect. We used plot physical
parameters (n = 655) to derive annual water balance. We calculated annual actual evapotranspiration (AET) as a
proxy for productivity and annual soil moisture deficit (Deficit) as a proxy for summer drought and used those values
to describe distributions for 17 tree species over the 2,300 m elevation gradient in Yosemite. We combined
vegetation plot data with precipitation, temperature, soil water capacity, slope, aspect and latitude data sets of
different resolutions to develop spatially explicit environmental templates – a potential improvement over models
where all input parameters have uniform grid size. We calculated tree species biophysical envelopes over broad
ranges of environmental gradients – in this study a range of 31.0 cm for soil water capacity, 33.4 °C for July mean
temperature, and 918 mm yr-1 for annual precipitation were noted. As climate change involves complex
interrelations between changes in temperature and precipitation, models using AET and Deficit may allow more
precise predictions of range shifts. We used present climatological averages, reconstructions of past climate, and
climate projections to evaluate changes in the water balance for locations where trees of each of 17 species are now
present. Changes in water balance from 1700 (“Little Ice Age”) to the present are small, but changes between the
present and expected climate in 2050 (1.5 °C warmer) are large and significant for most species.

 

Talk
TWENTIETH-CENTURY DECLINE IN LARGE-DIAMETER TREES IN YOSEMITE NATIONAL PARK, CALIFORNIA, USA

LUTZ, JAMES A. (1); VAN WAGTENDONK, JAN W. (2); FRANKLIN, JERRY F. (1)
(1) College of Forest Resources, University of Washington, Seattle, WA 98195-2100, (2) USGS Western Ecological
Research Center, Yosemite Field Station, El Portal, California, 95318

Between the mid-1930s and the 1990s, the density of large diameter trees in Yosemite National Park declined 24% (P <
0.001). The decrease was apparent in all coniferous forest types. Proportionate declines were higher in subalpine
and upper montane forest types, and less in lower montane forest types. Densities of large-diameter Pinus albicaulis,
Quercus kelloggii,
and Q. chrysolepis increased, but densities of large-diameter individuals declined for eleven other
common species. Three general patterns emerged. For Pinus ponderosa, P. jeffreyi, and P. lambertiana,
proportional decreases in large-diameter trees were greatest at lower elevations. For Abies concolor, A. magnifica, P.
contorta,
and P. monticola, proportional decreases were approximately uniform throughout the range. For Q.
chrysolepis, Q. kelloggii, Calocedrus decurrens, P. albicaulis
, and Pseudotsuga menziesii, increases in density of
large-diameter trees occurred only in the upper portions of their ranges. Within-plot richness, evenness and density
of large-diameter trees decreased for most species and most forest alliances. The reintroduction of fire to plots in
the Pinus ponderosa mixed coniferous forest alliances did not decrease the density of large diameter trees compared
to areas that had not burned since 1936. However, unburned plots retained few large-diameter P. ponderosa; the
large-diameter component shifted to A. concolor, C. decurrens, and Q. chrysolepis. The result for lower elevation
forests are consistent with increased moisture stress due to increasing overall tree density and with climate that has
warmed since the establishment of today’s large-diameter individuals. Results for large-diameter P. albicaulis are
consistent with a calculated recent decrease in annual soil moisture deficit at higher elevation. Comparisons of past,
present and future climate scenarios with respect to annual actual evapotranspiration and annual soil moisture deficit
suggest that the climate-driven portion of changes in the structure of these forests is likely to accelerate over time.

 

Talk
CLIMATE, LIGHTNING IGNITIONS, AND FIRE SEVERITY IN YOSEMITE NATIONAL PARK, CALIFORNIA, USA

LUTZ, JAMES (1); VAN WAGTENDONK, JAN (2); THODE, ANDREA (3); MILLER, JAY (4); FRANKLIN, JERRY (1)
(1) College of Forest Resources, University of Washington, Seattle, WA 98195-2100, (2) USGS Western Ecological
Research Center, Yosemite Field Station, El Portal, California, 95318, (3) School of Forestry, Northern Arizona
University, Box 15018, Flagstaff, Arizona, 86011, (4) USDA Forest Service, 3237 Peacekeeper Way, Suite 101,
McClellan, California, 95652

Continental-scale studies of western North America have attributed recent increases in annual area burned and fire
size to a warming climate, but these studies have focused only on large fires and have left the issues of fire severity
and ignition frequency unaddressed. We examined the relationship between decreasing snowpack and the ignition
and size of all fires that occurred in Yosemite National Park, California (area 3,027 km2) between 1984 and 2005.
During this period, 1,870 fires burned a total of 77,718 ha. We quantified fire severity for the 103 fires >40 ha with
satellite fire severity indices using 23 yrs of Landsat Thematic Mapper data. Increased spring snowpack exponentially
decreases the number of lightning ignitions (P < 0.001), and the proportion of the landscape burned at higher
severities increases with the log10 of annual area burned (P < 0.001). The principal mechanism whereby snowpack
mediates lightning ignitions is through the seasonal landscape flammability. A secondary mechanism is fewer lightning
strikes in years with higher April 1st snowpack. Future climate-induced decreases in snowpack and the concomitant
increase in fire severity suggest that existing assumptions about fire may be understated – future fires may be more
severe, and post-fire recovery may take longer. Using one forecast for snowpack, we project that the number of
lightning ignitions in Yosemite National Park from 2020 to 2049 will be 19.1% higher than between 1984 and 2005 and
that the annual area burned at high severity will increase 21.9%.

 

Poster
THE EFFECTS OF HABITAT AMELIORATION AND HERBIVORY ON SEEDLINGS OF PINUS LONGAEVA

MAHER, COLIN
UC Santa Cruz Department of Ecology and Evolutionary Biology, Santa Cruz, CA

Survival of conifer seedlings in desert environments can be strongly influenced by both positive and negative
community interactions. Pinus longaeva (bristlecone pine) trees in the White Mountains of California produce large
quantities of seeds each year, yet demographic data suggest that successful recruitment episodes occur only several
times a century. Therefore, it is likely that the germination and survival of first-year seedlings for this long-lived
species may be critically important elements of population dynamics. To better understand the factors that influence
the survival of first-year trees, I performed two field experiments with greenhouse grown P. longaeva seedlings. To
assess the impact of herbivory, I planted seedlings in full cages, open ended cages (cage controls), and uncaged
treatments in three situations on Campito mountain: within the bristlecone forest, in the sagebrush scrub slightly
lower in elevation than the current forest, and in the sagebrush scrub above the current forest. To test the effects of
habitat amelioration by dead wood and sagebrush (Artemisia tridentata), I planted seedlings in sagebrush scrub in
three caged treatments: underneath sagebrush, in the open spaces between sagebrush plants, and underneath shade
structures made from blocks of wood. In the first experiment, I found that seedlings were predated with greater
frequency within the bristlecone forest than in the sagebrush scrub. This result is consistent with the Janzen-Connell
distance hypothesis and indicates that herbivory is not an important factor influencing the boundary of the forest. In
the second experiment, I found that mortality was significantly reduced in seedlings shaded by a block of wood,
indicating that habitat amelioration (e.g., sun and heat protection) provided by dead wood may be important for
successful seedling establishment. Sagebrush had no significant effect on survival compared to the exposed intershrub
treatment, suggesting that sagebrush does not facilitate the establishment of P. longaeva seedlings.

 

Talk*
CLIMATE CHANGE EFFECTS ON RESTORATION PROCESSES AND ENDPOINTS IN THE MONO BASIN

MARTIN, DAVID W.
City of Los Angeles Department of Water and Power, Bishop, California City of Los Angeles Department of Water and
Power, Bishop, California

State Water Resources Control Board Decision 1631 and Order Nos. 98-05 and 98-07 require LADWP to monitor stream
flows, and to restore and monitor the fisheries, stream channels, and waterfowl habitat. LADWP has focused its
restoration program, on the specific goal of a fully functioning, self sustaining ecosystem. The streams as they exist
today are closer to that goal than during the years leading up to LADWP’s diversions, however, changing climate could
substantially affect the ability of various ecosystem components to resemble what many consider “restored”. The
ability to evaluate and predict how potential climate change scenarios may affect components of the Mono Basin
ecosystem requires tools that adequately accommodate the complex processes of ecological dynamics at various
spatial and temporal scales. One tool under development by LADWP is the application of the Ecological Dynamic
Simulation Model (EDYS) to land and water management to assist managers in selecting defensible strategies to best
meet difficult management objectives within regulatory constraints and variable climatic and disturbance scenarios.
EDYS is a mechanistic simulation model that simulates complex ecological dynamics across spatial scales ranging from
plots to landscapes and watersheds. Modules include climate, hydrology, soils, nutrient cycles, plant community
dynamics, herbivory, animal dynamics, management activities, and disturbances. Model scenarios that simulate shifts
in precipitation patterns and altered temperatures are being evaluated to determine potential effects on riparian and
wetland communities and may be useful in determining appropriate management approaches for the Mono Basin.

 

Talk
INDIRECT EFFECTS OF CLIMATE CHANGE ON PLANT-HERBIVORE INTERACTIONS AND COMMUNITY DIVERSITY PATTERNS IN THE EASTERN SIERRA NEVADA

MARTINSON, SHARON J.; LOIK, MICHAEL E.
University of California-Santa Cruz, Santa Cruz, CA

Ecosystems with harsh abiotic conditions tend to have fewer species than more temperate systems, and the species
that persist in these harsh environments have evolved to tolerate their conditions. Biotic interactions (e.g.
competition, herbivory, mutualisms) also tend to be very specific, and can be both directly and indirectly affected by
perturbations to abiotic conditions. The ecosystem of the eastern Sierra Nevada is shaped by limited precipitation,
predominantly in the form of snow. Great Basin sagebrush, Artemisia tridentata, a dominant shrub in this ecosystem,
is host to many species of gall-forming insects and other arthropods. Artemisia-dwelling insects represent a large
portion of the insect biodiversity in this system. The suitability of A. tridentata as a host for these insects will likely
change under future climate scenarios if the abiotic conditions are different than those conditions under which these
interactions evolved. Snow precipitation is one condition that is predicted to change in the future. Host suitability
may depend on the water status of the plant, so future snow conditions could change the number, diversity or
community composition of insects utilizing A. tridentata. To determine the effects of increased or decreased snow on
insects, we surveyed the galls on A. tridentata in areas with experimentally increased or decreased snow. We found
high diversity of gall morphotypes (> than 20), as well as several species of homopteran herbivores that were tended
by ants. We present patterns of insect diversity suggesting that insects are sensitive to plant responses to changes in
the snow regime. Ongoing research to determine the underlying mechanism of this indirect effect includes studying
how plant defense chemistry is affected by snow conditions. We also present findings suggesting that changes to
plant-herbivore interactions may alter the leaf litter from A. tridentata, which may affect the fire

 

Talk*
PREDICTED RESPONSES OF THE CALIFORNIA GOLDEN TROUT TO CLIMATE CHANGE

MATTHEWS, KATHLEEN R.
USDA Forest Service, PSW Research Station, Albany, CA 94701

The native habitat of the California golden trout (CGT), Oncorhynchus mykiss aguabonita, currently includes stream
areas on the Sierra Nevada Kern Plateau impacted by cattle grazing. As a result, some areas have reduced streamside
vegetation (willows or sedge), warmer stream temperature (up to 24°C), and lower dissolved oxygen (DO) than
restored areas that are typically 2-3°C cooler with higher levels of DO. Climate change may further compromise CGT
and their habitat in stream areas still subject to cattle grazing with predicted warmer water temperatures, possibly
lower dissolved oxygen, reduced flow, and increased sediment. In the Golden Trout Wilderness, where most native
CGT reside, many sections have yet to recover or are currently being grazed and have shallow, widened, unvegetated
sections that could subject CGT to harmful and possibly lethal levels of DO and water temperatures. Because the CGT
is a Species of Special Concern and petitioned for USFWS ESA listing, it will be crucial to monitor changes in riparian
condition and water quality to ensure their survival as warming occurs. Moreover, the overdue restoration of
vulnerable stream sections must quickly proceed to prepare for climate warming. Stream monitoring of degraded and
recovering stream sections will compare the temperature, DO, stream depth and width to determine if potentially
harmful conditions occur so that management actions can be implemented. While these monitoring actions are
already included in the CGT Conservation Strategy, it will be important to have frequent assessments and determine if
climate warming further stresses already vulnerable CGT populations on the Kern Plateau.

 

Talk*
EXTINCTION AND SPECIATION IN THE NORTH AMERICAN FLORA IN RESPONSE TO QUATERNARY CLIMATE CHANGES

MCLAUGHLIN, STEVEN P.
PO Box 819, Big Pine, CA 93513

Paleontologists, systematists, and biogeographers have concluded that both extinction and speciation rates are very
low, around 0.1 to 1.0 extinctions/speciations per species per million years. There is also widespread consensus that
migration rates in response to climate changes are high. Slow rates of macroevolutionary change coupled with high
migration rates should produce a biota where most of the species are widespread. For the North American flora (and
most other biotas), just the opposite is the case: the frequency distributions of range sizes is highly left-skewed with
many rare and local species and few widespread ones. A transition-probability model was developed to determine
what extinction, speciation, and migration rates can account for the modern frequency distribution of range sizes.
The results suggest that thousands of species of plants have originated and gone extinct with each major cycle of
global climate change during the past 2 million years. Total Quaternary speciations and extinctions have probably
exceeded 40,000 species. The implications of this research for conservation will be discussed.

 

Talk*
COMPLEX RESPONSES OF SUBALPINE FORESTS TO CLIMATE CHANGE IN THE EASTERN SIERRA NEVADA AND WESTERN GREAT BASIN

MILLAR, CONNIE; BOB WESTFALL; DIANE DELANY
USDA Forest Service, PSW Research Station, Sierra Nevada Research Center, Albany, CA

High elevation biota, including subalpine tree species and associated treeline, are commonly assumed to respond to
global warming by migrating upslope. This assumption generates a conservation hypothesis that habitat will be lost as
available area diminishes approaching mountain summits, with extirpations and extinctions as likely consequences. In
recent years we have been studying recruitment, demography, and mortality of high-elevation forests in the eastern
Sierra Nevada and western Great Basin ranges in response to paleoclimatic variability (past 3500 years) and to 20thcentury
warming and decadal variability. Conclusions from these studies suggest that subalpine forest responses to
warming climates are more complex than simple movements upslope. Using examples from our studies, we propose
the following types of responses to warming temperatures:
I. Subalpine Forest Densification (no treeline change)
A. General Subalpine Forest Infilling
B. Treeline (Ecotonal Zone) Infilling
C. Colonization of Formerly Persistent Snowfields
D. Colonization of Subalpine Meadows
II. Change in Tree Growth & Form (no treeline change)
III. Change in Patterns of Forest Mortality (no treeline change)
A. Change in Drought and Insect & Disease Effects
B. Change in Genetic Diversity & Adaptation
C. Change in Fire Relationships
IV. Change in Geographic Aspect of Forests (no treeline change)
V. Change in Elevation of Forests (with treeline change)
A. Differential Shifts in Elevation by Species (individualistic responses)
B. Shifts Downward in Elevation
C. Synchronous Shifts in Elevation by Multiple Species

 

Talk*
GEOGRAPHIC, PERIGLACIAL, AND CLIMATIC RELATIONSHIPS OF AMERICAN PIKA (OCHOTONA PRINCEPS) IN THE EASTERN SIERRA NEVADA AND WESTERN GREAT BASIN

MILLAR, CONNIE; BOB WESTFALL; DIANE DELANY
USDA Forest Service, PSW Research Station, Sierra Nevada Research Center, Albany, CA

American pikas (Ochotona princeps) are small herbivores restricted to patchily distributed, high-elevation, talus slopes
of western North American mountains. Pikas are vulnerable to brief exposures of direct heat and warm ambient
temperatures. This condition, coupled with increasing minimum temperatures during the past 120 years in western
North America, and the geometry of decreasing area on mountain peaks, has led to the species being considered at
risk from global warming. Increased monitoring has been urged. We documented 325 pika locations during 2007 and
2008 from the eastern Sierra Nevada (Tahoe Basin to Big Pine Cr) and six western Great Basin ranges (White-, Glass-,
Bodie-, Monitor Pass-, Sweetwater-, and Wassuk Mtn Ranges). We used a rapid assessment method based on fresh
pellets to find and voucher sites. This method indicates modern usage but not always current occupation, although at
most sites we also heard or saw pika, or found green vegetation in their haypiles. The sites ranged from 1827m to
3768m and were distributed on all slope aspects with a slight preference to NE and E. Over 80% of the sites occurred
in active or relict rock-ice features (RIFs), most commonly rock glaciers (cirque and valley wall) and boulder stream
landforms. Periglacial RIFs create ideal habitat for pika, including distribution of rock type and size, cold-air
ventilation in summer and warm-air circulation in winter (Balsch and chimney circulation), persistent wet meadows at
their base, patches of vegetation scattered on the rock carapace, and ideal conditions for predator avoidance and den
habitat. Because of their unique air ventilation, RIFs can depress local permafrost elevations as much as 1000 ft, and
thus provide excellent habitat for pika lower than what might be expected from average lapse rate gradients. The
climatic envelope of our pika sites (PRISM model) overall averaged 936 mm precipitation (range 279-1610 mm);
minimum temperatures averaged -3.7°C (range -6.8-0.6°C). Relative to normal distribution, minimum site
temperatures were skewed toward cold values, suggesting a disequilibrium loss of populations on the warm scale.
Elevation and minimum temperature of pika sites were not significantly correlated, suggesting that RIF environments
create adequate habitat not strongly related to elevation. Given documentation by other researchers of extirpations
of low-elevation historic pika populations, in our continuing work we will emphasize survey of low-elevation RIF sites.

 

Talk
ROCK GLACIERS AND RELATED PERIGLACIAL LANDFORMS IN THE SIERRA NEVADA, CA, USA; INVENTORY,
DISTRIBUTION, AND CLIMATIC RELATIONSHIPS

MILLAR, CONNIE; BOB WESTFALL; DIANE DELANY
USDA Forest Service, PSW Research Station, Sierra Nevada Research Center, Albany, CA

Rock glaciers and related periglacial rock-ice features (RIFs) are abundant yet overlooked landforms in the Sierra
Nevada, California, where they occur in diverse forms. We mapped 421 RIFs from field surveys, and grouped these
into six classes based on morphology and location. These categories comprise a greater range of frozen-ground
features than described in rock-glacier surveys elsewhere. Mapped features extended from 2225 m – 3932 m (modern,
mean 3333 m), occurred mostly on NNW to NNE aspects, and ranged in apparent age from modern to relict (late
Pleistocene). Many of the smaller features mapped are not readily discernible with remote (e.g., air photo)
observation; field surveys remain the best approach for their detection. We interpreted the presence of outlet
springs, basal lakes, suspended silt in outlet streams, and fringing phreatophytic vegetation, in addition to
morphologic indications of current rock movement, as evidence for interstitial ice, either persistent or seasonal. The
six classes were distinct in their geographic settings and morphologic conditions, indicating process-level differences.
To assess modern climate, we intersected mapped locations with the 30 arc-sec PRISM climate model. Discriminant
analysis indicated significant differences among the climate means of the classes with the first three canonical vectors
describing 94% of the differences among classes. Mean annual air temperatures (MAAT) for modern features ranged
from 0.3°C to 2.2°C; mean precipitation ranged from 1346 to 1513 mm. We calculated differences between modern
and Pleistocene temperatures in two ways, one based on elevation differences of modern and relict RIFs (662 m) and
standard lapse rate, the other using PRISM estimates. For the first, we estimate the difference in MAAT as -3.9°C
(range -2.2 to -7.9°C); from PRISM, the difference was -3.3°C (range -1.0 to -6.1°C). In that persistent snowfields and
glaciers are retreating in the Sierra Nevada under warming climates, RIFs will likely become increasingly important in
prolonging water storage during the warm season and providing small but distributed water reserves for biodiversity
and runoff. Their presence and water contributions would benefit by further hydrologic study.

 

Talk*
RESOURCE MANAGEMENT - KEEPING UP WITH CHANGE; EASTERN SIERRA HIGH ELEVATION FISHERIES AND NATIVE FAUNA

MILLIRON, CURTIS
California Department of Fish and Game, Fisheries Branch, 830 S Street, Sacramento, CA 95814

In keeping with its mission, the California Department of Fish and Game is committed to minimizing the effects of
climate change on the state’s natural resources through the development of adaptation and mitigation measures,
policies, and practices that provide clear benefits to fish and wildlife and recognize the uncertainty associated with
future climatic states. We are working to identify, respond, and prepare for climate change through landscape scale
efforts. See www.dfg.ca.gov/climatechange/.

Managing Eastern Sierra Nevada high elevation aquatic resources, including introduced trout fisheries and native
mountain yellow-legged frogs, is accomplished through the development and implementation of fisheries and aquatic
biodiversity basin management plans. The aim is to support robust populations of fish, wildlife, and natural
communities for their intrinsic and ecological values and their benefits to people. Some non-native fish populations
are being removed to benefit key native species. Where recreation is the preferred management direction, lakes may
continue to be stocked with hatchery fish, if needed to support quality fisheries.

Recognizing that emerging climate change science brings uncertainty, climate models generally predict reduced
snowpack and warmer water temperatures for the Sierra Nevada. Basin management planning must anticipate
changing conditions, respond to new information and resource monitoring data, and remain adaptive to meet the
following Eastern Sierra High Mountain Lakes project goal: Manage high mountain lakes and streams in a manner which maintains or restores native biodiversity and habitat quality, will support viable populations of native species, and provides for recreational
opportunities considering historical and future public use.

 

Talk*
HYDROCLIMATOLOGICAL TRENDS IN SNOW COVER DEPLETION AND SNOW WATER EQUIVALENT INFERRED OVER THE MODIS RECORD

MOLOTCH, NOAH P.; KWOK, ANGEL; MARGULIS, STEVEN; DOZIER, JEFF
Jet Propulsion Laboratory, California Institute of Technology, Pasadena CA, 91109

Hydroclimatological studies of snow cover depletion are now possible as we approach the first decade of Moderate
Resolution Imaging Spectroradiometer (MODIS) snow cover observations. Previous studies at watershed scales have
shown that these observations can be combined with spatially distributed snowmelt models to reconstruct the spatial
distribution of snow water equivalent (SWE). We extend this approach using a Bayesian SWE reconstruction technique
which combines time-series of remote sensing estimates of SCA with a land surface model (LSM) to estimate stormspecific
snowfall distribution with a retrospective data assimilation scheme. This approach exploits the inherent
relationship between the timing of snow disappearance and the magnitude of initial SWE. In this regard, we show that
the MODIS snow cover depletion record from 2001 - 2007 exhibited considerable interannual variability in both snow
cover persistence and reconstructed snow water equivalent. During wet years (2005-2006) snow cover persistence was
up 2 - 3 months longer than the average persistence over the observation period 2001 - 2007. Conversely, in the
drought year of 2007 snow disappeared approximately two months prior to the average date of snow disappearance.
Reconstructions of snow water equivalent were consistent with the snow cover persistence anomalies. These snow
cover persistence patterns and associated SWE reconstructions provide a means to explore spatially explicit trends in
snow accumulation and associated local and meso-scale controls.

 

Talk*
POPULATION DYNAMICS OF MULE DEER IN THE SIERRA NEVADA: INFLUENCE OF DENSITY AND CLIMATE

MONTEITH, KEVIN (1, 2); PIERCE, BECKY (1); BLEICH, VERN (2); STEPHENSON, THOMAS (1); KONDE, LORA (1)
(1) California Department of Fish and Game, Bishop, California; (2) Department of Biological Sciences, Idaho State
University, Pocatello, Idaho

Current models for climate change indicate increases in temperature over the next century. Consequently, a better
understanding of the complex associations of large-scale climate regimes, local weather patterns, and ecological
processes is necessary for both theoretical and applied science. Research to date has indicated, conclusively, that
climatic variability impacts population dynamics and timing of life-history events in large herbivores. Large herbivores
have been the focus of such research because herbivores are dependent on a variety of vegetative communities and
are sensitive to changes in landscape and vegetation characteristics influenced by climate change. Furthermore, large
herbivores function as keystone species, and understanding herbivore response to climate change may provide insights
into effects on whole ecosystems. We investigated long-term relationships between the El Nino southern oscillation,
precipitation, and population dynamics of a migratory mule deer (Odocoileus hemionus) herd that spends winters at
low elevation (< 1800m) on the eastern side of the Sierra Nevada in Round Valley near Bishop, California, and spends
summers at high elevation (> 2200m) in the Sierra Nevada on both sides of the Sierra crest. Population dynamics of
mule deer were influenced by density-dependent factors such as competition for forage, particularly on winter range,
and density-independent factors such as local weather patterns and large scale climate. We discuss the interaction of
density independent and density dependent factors on mule deer population dynamics and the implications of global
climate change on mule deer populations in the Sierra Nevada.

 

Talk*
RETHINKING RARE SPECIES PERSISTENCE: WHAT FRAMEWORK BEST PROVIDES FOR ASSESSING RISK AND
PRIORITIZING MANAGEMENT

MOORE, PEGGY
U.S. Geological Survey, Western Ecological Research Center, Yosemite Field Station, El Portal, CA 95318

Several frameworks have been offered to structure our thinking about rare plants in terms of type of rarity and in
terms of patterns of rarity. However, few of these have addressed issues of conservation biology. Stebbins and Major
(1965) provided us with a classification of California’s rare species based on their evolutionary history. Drury (1980)
and Rabinowitz (1981) used patterns of distribution and abundance to identify rarity classes. Such approaches can
provide the basis for protecting classes of species, but they may not be helpful in assessing risk to taxa from
anthropogenic impacts. Climate change impacts on rare plants include altered fire regimes, habitat fragmentation,
pollinator shifts, and plant community reassembly. Each of these has different implications for species with different
life histories. Farnsworth and Ogurcak (2008) used collection and visitation records to identify life-history
characteristics and ecological affinities that may place species at risk for decline. These included pollination mode,
dispersal strategy, and wetland status. More than evolutionary reasons for rarity or classes based on rarity patterns,
this kind of approach may provide the best chance of identifying species vulnerable to climate change effects.

 

Talk*
LONG-TERM MONITORING IN RIPARIAN HABITATS IN THE CONTEXT OF CLIMATE CHANGE

MOSS, STELLA; HEATH, SACHA; GEUPEL, GEOFFREY R.
PRBO Conservation Science, 3820 Cypress Drive #11, Petaluma, CA 94954

Although riparian areas account for less than 1% of the western U.S. landscape, they provide breeding and migratory
habitat for disproportionately more bird species than surrounding uplands. Thus, loss of riparian habitat has been
implicated as a key factor in western North American bird population declines, and riparian areas have been identified
as critical habitat for avian conservation in California. For seven years, PRBO Conservation Science has conducted
demographic monitoring in riparian habitats at Mono Lake. This work has used standardized methods that allow us to
evaluate changes in riparian bird communities that have occurred as a result of riparian restoration. Yellow Warblers
(Dendroica petechia) are a good example of a species that is quick to respond to restoration activities. Twenty years
ago, Yellow Warblers were documented as absent nesters on Rush Creek, today we found that Rush Creek harbors the
most abundant and densest breeding population documented in California. However, patterns of bird response to
riparian restoration may be altered by climate change as shifts in migration timing, initiation of breeding and
elevation and latitudinal distributions occur. These changes can only be monitored over long periods of time in a
standardized way while keeping in mind that other factors (e.g. land use and habitat restoration) are also important.
Standardized, long term monitoring will be the foundation to understanding changes in avian distribution in the
Eastern Sierra and through out California.

 

Talk*
INTEGRATED BIRD MONITORING IN THE EASTERN SIERRA: METHODS AND APPLICATIONS

MOSS, STELLA (1); HEATH, SACHA (1); SEAVY, NATHANIEL E. (1, 2); GEUPEL, GEOFFREY R. (1)
PRBO Conservation Science, 3820 Cypress Drive #11, Petaluma, CA 94954, (2) Information Center for the
Environment, University of California, Davis, CA 95616

Bird monitoring in the Eastern Sierra can contribute to our understanding of ecological change. An integrated
monitoring scheme that samples both population trends and demographic parameters of populations across broad
geographical regions and local microhabitats is important. Trend monitoring of multiple species can provide
information on groups of species that respond to the same ecological drivers. Demographic monitoring provides more
detailed information about the contribution of survival and fecundity to the observed trends. Since 1998, PRBO
Conservation Science has collected baseline data on bird populations along a more than 300km long stretch of the
Eastern Sierra. In this effort, we have employed standardized protocols, utilized both volunteers and professionals,
and provided regular results to management agencies. Our monitoring has documented, amongst other things, the
response of riparian birds to the restoration of Mono Lakes tributary streams and the potential for conifer
encroachment to change bird communities associated with aspen habitat. Today, our efforts provide a model for bird
monitoring that can document the ecological effects of climate change on Eastern Sierra’s bird communities.

 

Talk
THE ASSOCIATION BETWEEN TECTONISM AND PRESERVATION OF GLACIGENIC DEPOSITS OF CRYOGENIAN AGE (850- 630Ma) IN SOUTHEASTERN CALIFORNIA AND THEIR VALUE IN ACCESSING CORRELATION SCHEMES FOR SIERRAN GLACIAL DEPOSITS WITH PLEISTOCENE CLIMATE EVENTS

MROFKA, DAVID; KENNEDY, MARTIN
Department of Earth Sciences, University of California, Riverside

The record of Cenozoic climate change in the Sierras is unparalleled because of the combination of clear and
unequivocal glacial deposits and landforms, long-term proxy records of climate change bound within glacial and
closed-system playa lake deposits and abundant evidence for interaction between past climates, lake levels and floral
and faunal diversity. This climate record also shows an intimate association with abundant volcaniclastic deposits that
often bound and interbed with glacigenic deposits but have failed to provide the hoped-for radiometric age
constraints that would clearly define ages for what appear to distinct generations of glacial advance and retreat over
the prior ca. 760ka. This lack of radiometric age constraints has led to a reliance on more indirect dating methods
(i.e. dating carbon in tills and lake-terrace deposits) that, while providing evocative age data, are problematic and
fail to deliver the resolution that provides unequivocal correlation with well-understood global climate events during
the Pleistocene. Only 70 km to the southeast, the Death Valley region contains a similar interval of intimately
associated glacigenic and tectonic deposits recording of what was likely the Earth’s most severe period of cold climate
conditions and most abrupt and largest magnitude transition from nearly world-wide glaciation to a greenhouse
climate, during the Cryogenian Period from 850-630 Ma. As in the Sierras, resolution of distinct climate events has
been frustrated by a lack of radiometric age constraints and correlation with other global events of the same age
relies upon geochemical proxies and the coincidence of “events” between similar aged deposits worldwide. We show
here that preservation of Cryogenian glacigenic deposits in Death Valley is controlled by local tectonism and absent
radiometric age constraints should not be correlated with other deposits globally based solely on geochemical proxy
data and the coincidence of glacigenic intervals in the stratigraphic section.

 

Talk*
DEVELOPING A LONG-TERM MONITORING PROGRAM IN SIERRA NEVADA NETWORK NATIONAL PARKS

MUTCH, LINDA (1); ROSE, MERYL GOLDIN (2); HEARD, ANDREA (1); GRABAN, SANDRA (1); CHOW, LESLIE (1)
(1) Sierra Nevada Network, Sequoia and Kings Canyon National Parks, 47050 Generals Highway, Three Rivers, CA,
93271 (2) Sierra Nevada Network, Yosemite National Park, P.O. Box 700, El Portal, California, 95318

The Sierra Nevada Network (Devils Postpile National Monument, Sequoia and Kings Canyon and Yosemite National
Parks) is one of 32 Inventory & Monitoring networks across the National Park Service, established to do baseline
biological inventories and develop and implement well-designed, natural resource monitoring programs. The network
has completed a multi-year planning effort that engaged parks and outside scientists, and we are currently developing
detailed monitoring protocols for vital signs (i.e., ecological indicators) selected for monitoring. To prioritize vital
signs, park, network, and local USGS staff considered each vital sign’s ecological importance, management priorities,
and sensitivity to large-scale stressors such as climatic change, air pollution, altered fire regimes, non-native species,
and habitat fragmentation. Vital signs selected include: weather/climate, snowpack, water chemistry, surface water
dynamics (hydrology), amphibians, bird populations, wetland plant communities, wetland water dynamics, wetland
invertebrates, forest dynamics, fire regimes, invasive non-native plants, and landscape mosaics. The network has
completed its bird and lake protocols, and is currently implementing lake monitoring (water chemistry, hydrology, and
amphibians) in 3 parks. We are also field-testing our wetlands protocol. Other monitoring protocols are in various
stages of development. Challenges of developing a well-designed monitoring program with broad spatial inference in
large–predominantly Wilderness–parks will be discussed.

 

Talk*
THE PROGNOSIS OF ENDEMIC FISHES COMPLICATED BY CLIMATE CHANGE IN THE WESTERN GREAT BASIN

PARMENTER, STEVE
California Department of Fish and Game, Bishop, CA

Climate change models suggest hotter and drier conditions will prevail in the eastern Sierra Nevada and western Great
Basin. Model analysis of stream temperature dynamics in two California streams suggests these changes by themselves
will not increase water temperatures above critical thermal maxima for the region’s endemic and introduced fishes.
Edaphic factors do not currently drive the contemporary lower elevation limits of the native fishes. Four endangered
and two species of special concern are confined to hydrologically isolated refuges, having been excluded from their
natural habitats by introduced predatory fishes. These refuges are vulnerable to ontogenetic change, biological
invasion, and the genetic consequences of small population size; and tend to manifest a short population half-life.
Current conservation practice attempts to offset the instability of small refuges with redundancy, however, the supply
of suitable refuge sites is exhausted and the status of species needing refuges has not been stabilized. A majority of
refuges for valley-floor species are supplied by spring flow from poorly understood aquifers. Reduced recharge from
protracted drought, or regional reduction in precipitation, could eliminate certain critical habitats and magnify the
uncertainty implicit in the existing management strategy. The shortage of suitable refuge sites may be eased by
ongoing biopolitical initiatives, or by broader consideration of out-of-range translocations. On a Pleistocene temporal
scale, range extension into selected naturally inaccessible habitats may offer the greatest potential for insulating
local fish species richness from the combined effects of past anthropogenic insults and climate change.

 

Poster
AQUATIC MACROINVERTEBRATES IN MONTANE AND SUBALPINE WETLANDS: ASSEMBLAGE STRUCTURE AND INFLUENCE OF HABITAT TYPE AND WATER FLOW
(jpeg image file)

PIEROTTI, LYRA; HOLMQUIST, JEFFREY; SCHMIDT-GENGENBACH, JUTTA
University of California White Mountain Research Station, Bishop CA 93514

Temporary waters in montane and subalpine wetlands produce abundant macroinvertebrate fauna that connect
aquatic and upland habitats via a variety of ecosystem services. We surveyed aquatic invertebrate assemblages in
wetlands of Sequoia and Kings Canyon National Parks in order to assist the National Park Service with development of
a long-term monitoring plan. The program will also monitor terrestrial invertebrates, vegetation, and hydrology in an
effort to track the effects of climate change and other stressors in montane and subalpine wetlands. Habitats of
interest included fens, wet meadows, and an intermediate type ("peat accumulating wetlands"), and habitat type was
one of the variables upon which our random sampling was stratified. We sampled forty-one widely-distributed
backcountry sites during the summer of 2008. We established a plot at each site to characterize the plant
assemblage, and the nearest temporary water was sampled using a D-frame net. Flow of the sampled temporary
waters was typically either zero or very low (<1 cm/sec).

Forty families from thirteen orders were represented in our macroinvertebrate collections. The samples were
dominated by clams and Diptera (particularly midges), but beetles (particularly predaceous diving beetles), mayflies,
and mites were also common. Despite the high mean abundance of clams, variance was high, and clams only occurred
in 63% of the samples. Neither assemblage-level nor population metrics were significantly related to habitat type (3x2
ANOVAs; three habitat types and flow/no flow). In contrast, water flow was a significant influence on a variety of
metrics, including family richness (Margalef's corrected), percent Ephemeroptera-Plecoptera-Trichoptera (mayflies,
stoneflies, and caddisflies), and clam, mite, mosquito, and caddisfly abundances. There was also a significant overall
influence of flow, but not habitat type, across all examined response variables (sign tests). Water flow appears to be
a more important factor than habitat type in structuring these temporary wetland assemblages.

 

Poster
THE HYDRAULIC TRADE-OFFS ASSOCIATED WITH EMBOLISM RESISTANCE IN NORTH-TEMPERATE AND SOUTHERN HEMISPHERE CONIFERS

PITTERMANN, JARMILA (1)
Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95060

Conifers are a dominant element of the north temperate flora where they occupy a broad spectrum of habitats. By
contrast, southern hemisphere conifers form a smaller component of the native forests and are thought to be
relictual. However, it is generally agreed upon that conifers succeed in climates frequently characterized by poorquality
soils, extreme temperatures and variable water availability. All of these factors can impair water transport by
triggering air-entry and its subsequent expansion in the water column, a phenomenon commonly referred to as
embolism. Conifers have evolved a suite of xylem patterns designed to reduce their vulnerability to drought- and
freezing-induced embolism, so what are the hydraulic trade-offs associated with resistance to this stress? Freezethaw
cycles can trigger embolism when air freezes out of the xylem sap and forms a bubble that can expand under
sufficient negative xylem pressure. Here, I present data to show that this is much more likely to occur as tracheid
diameter increases, creating a direct tradeoff between conducting efficiency and vulnerability to freezing-induced
xylem failure. Drought-induced embolism is created by air-entry into the conduit via the inter-tracheid pit membrane
and no clear trade-off exists at the pit level. However, tracheid walls require sufficient fortification to resist
implosion under negative pressure, which translates into greater carbon costs and reduced tracheid lumen diameter.
Consequently, reduced water transport efficiency is also correlated with drought-induced embolism resistance. The
relationship between transport efficiency and resistance to drought-induced embolism appears to be de-coupled in
southern hemisphere conifers belonging to the Cupressaceae, Podocarpaceae and Araucariaceae. This suggests that
phylogenetic constraints may preclude these taxa from optimizing the structure-function of their xylem.

 

Talk*
TIME DOMAINS OF BIOLOGICAL RESPONSES TO GLOBAL ENVIRONMENTAL CHANGE

POWELL, FRANK L.
White Mountain Research Station and Dept. of Medicine, UC San Diego, La Jolla, CA 92093

Physiology determines the direct effect of any environmental change on a plant or animal. Hence, the biological
consequences of global change in the environment depend upon the relationship between the rates of environmental
change and physiological responses to the change. Of course, this relationship is modulated by other factors,
including an organism’s ability to modify its environment (behavior), changes in the acute physiological response
(acclimatization), genetic changes through evolution (adaptation), and secondary changes in the environment that
affect all of the above (ecology). All of these factors operate over different time domains, from seconds to
generations, which further complicates predicting the biological consequences of global climate change. One
approach to this problem is to study biological responses to other global environmental changes occurring over the
history of life on earth. Oxygen levels in the atmosphere have varied between 13% and 30% over the past 600 million
years. Rapid and large changes in atmospheric O2 levels correlate with profound changes in animal life. Notable
examples include insect gigantism 300 million years ago when O2 was at its peak and massive extinctions when O2
plummeted to its nadir in the Permian 250 million years ago. More rapid changes in environmental O2 have occurred
with mountain building and still more rapid changes have occurred in terrestrial environments with migrations and
currently in marine environments with eutrophication of coastal waters. The rates of behavioral, physiological,
evolutionary and ecological responses to O2 change can all be measured. Therefore, it should be possible to test
various models that predict the biological effects of environmental O2 change based on interactions between the rate
of change and rates of response. Such models may be useful for predicting the consequences of other changes such as
the current change in global climate.

 

Poster
AEOLIAN ADDITIONS: THE DOWNWIND EFFECTS ON SOIL AND VEGETATION IN OWENS VALLEY

QUICK, DAYNA J. (1); REHEIS, MARITH C. (2); STEWART, BRIAN W. (3); CHADWICK, OLIVER A. (1)
University of California, Santa Barbara, Santa Barbara, CA 93106, (2) U.S. Geological Survey, Denver, CO 80225, (3)
Department of Geology and Planetary Science, University of Pittsburgh, Pittsburgh, PA

We present results from an ongoing study of soil-ecosystem responses to dust flux from Owens Lake Playa in Owens
Valley over the past century. Our goal has been to document the spatial impact of the dust by explicitly considering
distance from the playa and the contrast between the chemistry and mineralogy of the playa derived dust and the
background, regional dust rain that has impacted the soils at least during the Holocene. We have sampled soils along a
transect running from north to south along the valley axis to compare accumulation of salts and fine-grained minerals
both with respect to dust trap samples collected by the US Geological Survey and with respect to distance from the
playa source for the dust. These sampled soils are from sites selected on alluvial fan deposits emanating from the
Sierra Nevada Batholith granites. We know that there is a distinct contrast in trace element chemistry, Sr isotopic
composition and particle size among the granitic parent material, the playa sediments and the regional dust rain.
These contrasts will allow us to develop quantitative estimates of not only the role of salts and fines in the soil
profiles and in plant leaf chemistry but also to assign fractions of contribution from different sources. Early results do
demonstrate a higher level of salts in soils adjacent to the playa, as well as a clear Sr signature from the playa. Our
results will move the analysis of the prodigious dust clouds that are thought to impact human health to an analysis of
their impact on the ecosystems of Owens Valley. An evaluation of the severity of that impact is a critical step toward
assessing management decisions related to Owens Lake Playa as well as other similar dust sources such as the Salton
Sea that may become desiccated in the future.

 

Talk*
RELATIONSHIPS BETWEEN SIERRA NEVADA CLIMATE VARIABILITY, GENETIC VARIATION IN NATIVE INSECT POPULATIONS, AND EFFECTS OF ENVIRONMENT AND GENETICS ON POPULATION DYNAMICS

RANK, NATHAN (1,3); DAHLHOFF, ELIZABETH (2,3); SMILEY, JOHN (3)
(1) Sonoma State University, Rohnert Park, CA 95472, (2) Santa Clara University, Santa Clara CA, (3) White Mountain
Research Station, Bishop, CA 93514

Fluctuations in natural populations are thought to depend on an interaction between the local environment and the
genetic characteristics of the species that in inhabit it, yet there is surprisingly little empirical evidence to support
this hypothesis. Sierra Nevada populations of the leaf beetle Chrysomela aeneicollis fluctuate greatly in abundance
among years and these fluctuations often result in local extinction. To assess the relationship between local
environment, genetics, and abundance, we have quantified environmental temperatures, population genetics, and
beetle abundance in three neighboring drainages in the eastern Sierra Nevada (Big Pine Creek, Bishop Creek, and Rock
Creek). We have conducted population genetic surveys since 1988 and assessed population sizes annually since 2000.
Over the past 10 years, we have also recorded air temperatures in each drainage. Analysis of variation at mtDNA loci
suggests that migration among drainages rarely occurs, and this is supported by census data that show that
populations fluctuate independently in each drainage. We have observed a gradient in allele frequency at the enzyme
locus phosphoglucose isomerase, which coincides with a north-south temperature gradient. PGI allele 4 predominates
in Big Pine Creek, the warmest drainage and allele 1 predominates in Rock Creek, the coolest drainage. Allele
frequencies are intermediate in Bishop Creek. We also found that PGI allele 1 increased in Bishop Creek over 8 yrs
when conditions were cool and wet. During a single summer, PGI allele 1 increased in frequency during the early
summer, and PGI allele 4 increased when conditions were warmer. We used path analysis to integrate the
environmental and genetic influences on population genetics and found that temperature and PGI variation both
played an important role.

 

Plenary Talk*
CLIMATE MONITORING AND TRENDS IN THE CENTRAL AND SOUTHERN SIERRA NEVADA

REDMOND, KELLY T. (1); ABATZOGLOU, JOHN T (2)
(1) NOAA Western Regional Climate Center, Desert Research Institute, Reno NV 89512-1095, (2) Department of
Meteorology, San Jose State University, San Jose CA 95192-0104

As a contribution to CIRMOUNT (Consortium for Integrated Climate Research in Western Mountains), several new highelevation
climate monitoring stations have been deployed or augmented in recent years. These are intended to
complement and extend efforts at low-to-mid elevations. Another dense network with high temporal resolution was
deployed for studies of mountain waves in the atmosphere (TREX), and has been gathering data in the Owens Valley
near Independence for four years. Measurements from these and other platforms now have sufficient length to begin
to offer insights into climate behavior in these locations. Reanalysis data sets show annual climate warming at the
higher elevations. The rate of warming is not uniform in time, and varies considerably by season and by month. At
higher elevations, spring shows the greatest warming (though with recent interruptions), winter shows somewhat less,
and autumn shows almost no warming; summer has shown little warming until the turn of the new millenium. In
recent years, greater annual warming is seen at higher elevations than at lower elevations. Reanalysis data can be
used in concert with in situ surface measurements to reconstruct missing periods, and earlier periods prior to station
establishment. Reanalysis data are based primarily on upper air measurements; surface-based data for the Sierra
Nevada show similar trends. Not all stations necessarily show warming. Issues relating to the interpretation of these
records will be discussed.

 

Talk*
CLIMATE INFORMATION NEEDS FOR THE NATIONAL PARK SERVICE IN THE SOUTHERN SIERRA NEVADA

REDMOND, KELLY T.; EDWARDS, LAURA M.
NOAA Western Regional Climate Center, Desert Research Institute, Reno NV 89512-1095

An assessment was performed to evaluate the adequacy of climate data and monitoring for the Yosemite, Devils
Postpile, Kings Canyon and Sequoia units of the National Park Service (NPS) as part of their Inventory & Monitoring
Program. Climate data and information are important for operations, research, and the interpretive mission of NPS,
and for planning by visitors. NPS units generate weather and climate data themselves, act as hosts for other
monitoring activities, and make use of data and information from nearby sites outside park boundaries. Geographic,
elevational, and biome coverage was examined. Other topics covered included the length and quality of records, the
level of redundancy and backup, and the ability to detect climate change. A correlation analysis was performed for
temperature and precipitation. This included monthly, seasonal and annual averages and totals, and revealed patters
related to elevation, to east-west (cross-Sierra and Sierra Nevada-Central Valley) location, and to north-south
(Sequoia-Yosemite) location. The major findings of this study will be discussed.

 

Talk*
PEAK FLOW FORECASTING AND MANAGEMENT OF MONO LAKE’S TRIBUTARIES

REIS, GREGORY J. (1); VORSTER, PETER (2)
(1) Mono Lake Committee, Lee Vining, CA, (2) Consulting Hydrologist, Oakland, CA

State Water Resources Control Board Decision 1631 and Order Nos. 98-05 and 98-07 require the Los Angeles
Department of Water and Power (LADWP) to release specified peak flows on Rush Creek, Parker Creek, Walker Creek,
and Lee Vining Creek. Except for Rush Creek, these creeks have no LADWP-controlled storage and Parker and Walker
Creeks typically remain undiverted. Lee Vining Creek requires accurate peak flow forecasting and flexible, adaptive
management of water diversions since LADWP is required to allow Lee Vining Creek’s primary peak to pass undiverted,
while diversions are generally maximized through the rest of the snowmelt runoff period to fill Grant Reservoir,
augment Rush Creek peak flows and for export to Los Angeles. LADWP forecasts each year’s peak flow based on data
from previous years, however, real time management of the peak requires knowledge of the current weather,
snowpack, and upstream reservoir conditions. The Mono Lake Committee makes peak flow management
recommendations to LADWP by tracking several indicators of snowmelt runoff to develop forecasts of peak flow
timing. The indicators are combined into a “snowmelt index,” the relative magnitude of which indicates increasing or
decreasing flow. Peak flows can be forecasted when indicators exceed certain thresholds, including loss of snow water
content from snow pillows, hours above freezing for certain weather stations, and days of above specified nighttime
low temperatures at various stations. We are investigating whether the forecasts can be improved with GIS data to
assess soils, aspects, and elevation bands within the Lee Vining Creek drainage.

 

Talk*
CLIMATE CHANGE EFFECTS ON PREDATOR/PREY INTERACTIONS: HOW CAN WE CONSERVE PERSISTENCE AND RESILIENCE IN A MURKY SEA OF IDOSYNCRASY?

ROBERTS, SUSAN L.
US Geological Survey, Western Ecological Research Center, Yosemite Field Station, Wawona, CA 95389, USA

Ecosystem function and persistence depend on a variety of ecological processes being intact and resilient. Feedback
loops are integral to these dynamic ecological processes and a change in one or more feedbacks requires adjustments
in other feedbacks in order for the process to continue generating a functioning ecosystem. Climate affects numerous
ecological processes, many of which shape habitat structure and composition. Habitat structure and composition
determine ecosystem inhabitants, who are themselves a loop in the feedback of the system and perform important
ecological processes such as seed dispersal, food production, or population stability. As research begins to show
changes in weather, patterns of snow accumulation, and vegetation distribution, we are left with the question; how
do these changes affect the animals that rely on these changing habitats? Predators, whether they are at the center
of the food web or on the edges, can only persist with the occurrence of stable prey abundance in conjunction with
the presence of specific habitat requirements such as den sites or hunting perches. As the habitat requirements vary
between different predator and prey species, climate changes resulting in changes in the physical environment or
habitat structure will most likely create species-specific, idiosyncratic results. To promote functioning predator-prey
systems in a changing climate, we need to determine what habitat requirements provide resiliency in the system and
ensure animals have access to these requirements. It is important to maintain spatial continuity between changing
habitats to ensure predators can pursue their prey as both predator and prey seek suitable areas to rest, forage, and
reproduce.

 

Talk
GLACIAL CHRONOLOGIES ALONG THE EASTERN SIERRA NEVADA FROM BE-10 SURFACE EXPOSURE DATING

ROOD, DYLAN H. (1, 2); BURBANK, DOUGLAS W. (2); FINKEL, ROBERT C. (3)
(1) Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94550; (2)
Department of Earth Science, University of California, Santa Barbara, CA 93106; (3) Department of Earth and
Planetary Science, University of California, Berkeley, CA 94720

A deeper understanding of the timing and extent of global paleoclimate variations includes knowledge of the age,
duration, and extent of alpine glaciations around the world. Cosmogenic nuclide surface exposure dating allows more
accurate, high-resolution chronologies in the 100-100,000 year temporal window to be developed for geomorphic
features that serve as records for past alpine glaciations. Our Be-10 results include ages for glacial landforms along
the eastern Sierra Nevada between Sonora Pass and Mono Basin (including deposits in the West Walker River, Buckeye
Creek, Robinson Creek, Green Creek, Virginia Creek, and Mill Creek catchments). We produced >100 Be-10 ages for
boulder samples and depth profiles from 8 glacial moraines and 4 outwash terraces spanning MIS 2 through 6. Our data
for the Last Glacial Maximum (MIS 2) are remarkably tightly clustered and support a central age with a small error ~3-
6%; e.g. 17.2 +/- 0.5 ka and 19.5 +/- 1.2 ka). A similar clustering even holds for an outwash surface associated with
the penultimate glaciation (MIS 6) for which the error is ~7% (136 +/- 10 ka). Our results generate within the study
area a paleoclimate record spanning the past >100 ky using Be-10 that allows comparison to LGM and older glacial
chronologies and proxy records globally. Also, recent work at CAMS-LLNL demonstrates the feasibility of dating
Holocene moraine sequences in the Sierra Nevada during time periods when radiocarbon dating methods are limited
(e.g. the Little Ice Age).

 

Poster
PHYSIOLOGICAL TOLERANCE AND CLIMATIC NICHE OF THE WEB-TOED SALAMANDERS (GENUS HYDROMANTES) OF THE SIERRA NEVADA

ROVITO, SEAN M.
Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720-3160

The Mt. Lyell Salamander (Hydromantes platycephalus) is endemic to the Sierra Nevada, with populations at both high
elevations in the alpine zone and in canyons of the Eastern Sierra Nevada at lower elevation. The closely related
Limestone Salamander (Hydromantes brunus) is endemic to the Merced River valley of Mariposa Co., CA. Populations
of H. platycephalus in the high Sierra Nevada experience much colder temperatures throughout the year than those in
the Eastern Sierra Nevada, and might therefore be expected to have evolved increased physiological tolerance for
cold. By contrast, populations in the Eastern Sierra Nevada, especially those at lower elevations in the Owens Valley,
are exposed to warmer temperatures and would be expected to show an elevated tolerance for higher temperatures. I
measured critical thermal minimum (CTmin) and maximum (CTmax) at two acclimation temperatures (4° and 15°C)
for H. platycephalus from the northern and southern high Sierra Nevada, the Owens Valley and H. brunus.
Surprisingly, none of the populations of H. platycephalus differed in their thermal tolerances, despite experiencing
markedly different thermal environments in nature. Hydromantes brunus, however, had a significantly lower CTmax
than all populations of H. platycephalus, despite living at much lower elevation than H. platycephalus. While some
populations of salamanders differed significantly in their CTmin and CTmax depending on acclimation temperature, others showed little acclimation response. These results will contribute to a better understanding of the climatic niche and tolerances of Hydromantes in California, which will help to identify areas and populations at risk from rising global temperatures.