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The study of evolution in natural populations has advanced our understanding of the origin and maintenance of biological diversity. For example, long term studies of wild populations indicate that natural selection can cause rapid and dramatic changes in traits, but that in some cases these evolutionary changes are quickly reversed when periodic variation in weather patterns or the biotic environment cause the optimal trait value to change (e.g., Reznick et al. 1997, Grant and Grant 2002). In fact, spatial and temporal variation in the strength and nature of natural selection could explain the high levels of genetic variation found in many natural populations (Gillespie 1994, Siepielski et al. 2009). Long term studies of evolution in the wild could also be informative for biodiversity conservation and resource management, because, for example, data on short term evolutionary responses to annual fluctuations in temperature or rainfall could be used to predict longer term evolution in response to directional climate change. Most previous research on evolution in the wild has considered one or a few observable traits or genes (Kapan 2001, Grant and Grant 2002, Barrett et al. 2008). We believe that more general conclusions regarding the rate and causes of evolutionary change in the wild and selection’s contribution to the maintenance of genetic variation could be obtained by studying genome-wide molecular evolution in a suite of natural populations. Thus, we have begun a long term study of genome-wide molecular evolution in a series of natural butterfly populations in the Greater Yellowstone Area (GYA). This study will allow us to quantify the contribution of environment-dependent natural selection to evolution in these butterfly populations and determine whether selection consistently favors the same alleles across space and through time.
Understanding the influence of habitat and climate on wildlife nutrition, reproduction and demography is a major goal for natural resource managers and ecologists alike. Although both top-down (i.e., predation and disease) and bottom-up (i.e. habitat and nutrition) forces impact demography, the nutritional condition of an animal is an integration of its environment (Parker et al. 2009) and influences reproduction and survival (Clutton-Brock et al. 1987, Keech et al. 2000, Cook et al. 2004), thus allowing for the identification of limiting factors. Researchers and managers must understand which factors limit population growth before mitigating actions can be taken.
Spatial and temporal variations in grassland phenology are thought to play a critical role in migration patterns of large herbivores in the Greater Yellowstone Ecosystem. Phenology, referring to the timing of green-up in this study, is directly related to biomass and forage quality. Migratory elk (Cervus elaphus), therefore, are believed to follow phenology across an elevation gradient during the growing season to maximize their access to high quality and quantity of forage. Concern that climate change and human land use alterations of phenology may impact the benefits of elk migration highlights the need for landscape-scale vegetation phenology monitoring. Satellite-derived Normalized Difference Vegetation Index (NDVI) shows potential as a remote sensing tool to predict landscape-level shifts in grassland phenology, but is limited by a lack of validation at varying scales, seasons, and in human land use areas. This study is focused on validating the accuracy of satellite-derived NDVI in estimating grassland phenology, biomass, and forage quality throughout the summer growing season within elk migratory ranges in the Upper Yellowstone River Basin. Results from this study will provide managers and researchers with information on the accuracy of NDVI as a tool for monitoring the effects of climate change and human land use on grassland dynamics relevant to migratory elk.
The deposition of anthropogenic reactive nitrogen (N) in alpine ecosystems can have multiple deleterious effects on plants, soils and hydrology in both the alpine and areas downstream through leaching and export. Thresholds for ecological responses to N deposition have been established for lakes, soils and changes in plant community composition in some areas of the Rocky Mountains. These thresholds offer a target for land and air resource managers to prevent significant changes in ecosystem function, however the underlying feedbacks controlling ecosystem response have not been fully examined. Research originally proposed in association with our UW NPS Small Grant aimed to examine plant to ecosystem interactions within alpine moist meadows between two sites receiving different levels of N deposition. This focus has been modified, in response to site limitations, to examine the mediation of the N cycle by the alpine moist meadow plant community.
Survival in variable environments often requires careful allocation of resources to competing physiological and behavioral functions. Because these competing processes often have additive energetic costs (Hawley et al. 2012), a limited resource pool forces individuals to make difficult trade-off decisions regarding energetic investments (Lochmiller and Deerenberg 2000). These trade-offs are a cornerstone of life-history theory that is aimed at determining the optimal allocation strategies in variable environments (Ricklefs and Wikelski 2002), and understanding their physiological and ecological consequences has renewed poignancy in the face of the unprecedented rate of anthropogenic environmental change occurring across the planet.
Across their native ranges, cutthroat trout populations are imperiled due to habitat loss, habitat alteration, and introduction of non-native species (Liknes and Graham 1988, Behnke 1992, Hitt et al. 2003). These changes have not gone undetected and a great deal of time and money have been invested in conservation and restoration of cutthroat trout populations (Kershner 1995, USDA 1996, Young and Harig 2002, Baker et al. 2008). The success of these projects is tightly linked to the ability of resource managers to prioritize management efforts. Specifically, where should the investments of time and money br focused to yield the greatest impact on conservation and restoration. This study proposes to use a relatively new, proven analytical tool, stable isotope analysis, to identify differences in the stable isotope signatures of tributary streams entering Jackson Lake. These differences are translated into the tissues, specifically otolith bones, of cutthroat trout that use these tributaries during early life stages or upon return for spawning (Kennedy et al. 2002, Muhlfeld et al. 2005, Coghlan et al. 2007, Barnett-Johnson et al. 2008, Walther et al. 2008, Ziegler and Whitledge 2010). The ability to link adult trout back to their natal origins and identify where these adults are returning to spawn will provide the data resource managers need to prioritize conservation and restoration efforts in the upper Snake River watershed, with special emphasis on tributary streams entering Jackson Lake.
This report was a result of volunteer research orchestrated by Katy Duffy, Interpretive Planner, Yellowstone National Park. The data collection was a direct need for grant compliance for the National Science Foundation associated with exhibits for the new Old Faithful Visitor Education Center, which opened to the public in August, 2006. The objective of this research was to understand visitor interaction with these exhibits using an unobtrusive form of data collection.
Understanding succession following severe wildfire is increasingly important for forest managers in western North America and critical for anticipating the resilience of forested landscapes to changing environmental conditions. Successional trajectories set the stage for future carbon storage, abundance and distribution of fuels, and habitat for many species. Early successional forests are increasing throughout the West in response to greater fire activity, but few long-term studies have considered succession following stand-replacing wildfires over large areas. The size and heterogeneity of the 1988 Yellowstone fires created novel opportunities to study succession at an unprecedented scale following severe fire, and we have studied the consequences of these fires for >20 years. In 2012, we began a re-sampling effort in long-term vegetation plots within the area burned by the 1988 fires to answer three overarching questions: (1) Are stand structure and function beginning to converge twenty-five years after the Yellowstone Fires, and what mechanisms may contribute to convergence or divergence? Heterogeneity in forest structure was the rule after the 1988 fires, and postfire lodgepole pine (Pinus contorta var. latifolia) densities ranged from zero to >500,000 trees/ha. The post-1988 cohort of lodgepole pine is reaching a time of critical transitions in structure and function. (2) Are plant community composition and species richness converging or diverging across gradients in local fire severity, post-fire lodgepole pine density, elevation and soil type a quarter-century after the 1988 fires? A central objective in our research has been to understand the relative influence of contingent factors (e.g., local fire severity) vs. deterministic factors (e.g., elevation, soils) on postfire ecosystem development, and how these influences may change through time. (3) How do canopy and surface fuels vary across the postfire landscape, and how will the variation in fuels influence potential fire behavior a quarter century post-fire? Field sampling was conducted for this third question during summer 2012, and data analyses and interpretation are in progress. Overall, results from the proposed study will enhance understanding of succession after one of the most notorious fires of the 20th century. Yellowstone’s postfire forests may serve as benchmarks for forests throughout the region and effective sentinels of change for the Rockies.
Invertebrates are receiving an increasing amount of conservation attention across North America. Currently, about 40% of the animals listed under the U.S. Endangered Species Act (ESA) are invertebrates (www.NatureServe.org). The National Park Service and other agencies require better information on invertebrate faunas in order to effectively conserve this important group of animals. One way to prioritize invertebrate groups for study is to assess the number of rare taxa within a given genus. In this context, Oreohelix (mountainsnails) are a top priority because the genus is assumed to support a very high percentage of rare and endemic taxa. Additionally, Oreohelix species in Wyoming and surrounding states have been petitioned for ESA listing in the recent past. The diversity of Oreohelix forms in Wyoming is not well-understood, and the current taxonomy may not reflect the true pattern of diversity within the state. Therefore, we are studying both the morphology and genetic structure of Oreohelix in Grand Teton National Park to begin to understand the diversity of mountainsnails in the state. We collected Oreohelix from 4 locations in Grand Teton National Park. Based on shell and internal characteristics, all individuals were identified as O. subrudis. We are currently preparing specimens for DNA sequencing.
The pristine, protected ecosystem of Grand Teton National Park (GRTE) is the ideal location to study the relationships between butterfly populations and the habitats on which these insects depend. Two montane meadow butterfly species, Parnassius clodius and Parnassius smintheus, were investigated in this study to identify patterns of habitat occupancy relating to variables across GRTE and into the surrounding territory of Bridger–Teton National Forest (BTNF). Population dynamics of P. clodius have been intensively studied by our research group over several consecutive years in one isolated population in Grand Teton National Park. However, little has been investigated regarding the Parnassian butterflies’ population range across the GRTE ecosystem. For this study, presence-absence butterfly surveys were conducted across 45 meadow sites in preferred habitat during the Parnassius flight season (June – July 2013). We found that P. clodius occupied 80% of the meadows surveyed, which was far greater than was originally predicted. P. smintheus, the more rare Parnassian butterfly in the GRTE ecosystem, was only found at 9% of the meadows surveyed. Understanding population ranges and habitat limits of these butterfly populations will be useful for managers and scientists within GRTE, and will assist conservation efforts for other related Parnassian species that are threatened or endangered worldwide due to habitat loss and climate change.
The Teton Range is the result of active crustal extension (normal faulting) and is the youngest range in the Rocky Mountains at approximately 2 million years old. This makes it a particularly attractive landscape to study, especially in terms of landform development and morphology because of its youth, state of seismic activity, and its recent deglaciation. These factors have combined to produce a unique fluvial landscape in that the fault-shattered metamorphic/igneous rocks of the range have been/are being eroded from their source cliffs at high rates which has covered the glacially scoured valley floors with colluvium such as talus slopes, rock slide, avalanche, and debris flow deposits. This project was focused on the characterization of all forms of mass movement, especially rock slides, multiple talus types (rockfall, alluvial, avalanche), protalus lobes, protalus ramparts, lobate and tongue-shaped rock glaciers, and their collective effects on water retention and its late-season delivery in the Grand Teton National Park, WY. A major goal of this project was to reclassify many of the mass movements in the park in an effort to streamline and simplify previous efforts by other scientists. Methods used during this study included field reconnaissance and measurements acquired during the summers of 2010 and 2013 and measurements taken from various datasets (NAIP imagery, shape files used within a GIS [ArcMap 10.0], and Google Earth™). Mass movement deposits, as well as ice glaciers and long-term snowbanks, were mapped and interpreted. Overall conclusions are that the major sources of mass movements from the Archean crystalline core of the range are the result of extensive jointing, fault-shattering, increased frost-wedging at higher altitudes, slopes steepened by prior glacial erosion, and extensive snow avalanches. Areas of Paleozoic sedimentary rocks marginal to the crystalline core produce rockslides as a result of steep dips and unstable shales beneath massive overlying carbonates. The presence of internal ground ice enables development of protalus lobes, thicker rock-fragment flows, and thinner boulder streams. Such ground ice is likely to enhance late-season water delivery downstream unless climate warming and recurrent droughts become too extreme.
From a vantage point on a rise above the Snake River, the valley below is shrouded in darkness. A faint glow on the eastern horizon heralds the dawn. The only sound comes from the river as water gurgles over rocks and other impediments. As the sky grows brighter, the shadows in the valley begin to take form, revealing numerous small streams that braid through dense thickets of willows and other shrubbery before returning to the main river channel. Small dark shapes dart among the trees and shrubs, filling the air with a variety of birdsongs. As the rising sun gradually illuminates the valley a herd of elk rise, one-by-one, in a distant meadow and begin grazing on the spring grasses. Moments later a cow moose and her calf emerge from behind the willows at the water’s edge, scattering the birds. This area, with its mosaic of habitats, teems with wildlife. It is not surprising, then, that this upper part of Jackson Hole became the chosen site for the Jackson Hole Wildlife Park (JHWP) and became the Park’s main animal viewing area for tourists and scientists alike.
Whitebark pine (Pinus albicaulis) is the only pine keystone species found in North America. Although it is considered a keystone species in high elevation ecosystems in the northern Rockies, it occupies a relatively restricted range and its future is uncertain. In modern times, it has experienced a significant decline in population due to pine beetle infestations, blister rust infections, fire suppression, and climate change. Despite the knowledge that the species is severely threatened, little is known about its paleoecology. More specifically, much remains unknown about how the distribution and stability of whitebark pine were affected by past climate change. The purpose of this study is to determine in great temporal and spatial detail the demographics of the current stand of whitebark pine trees in the watershed surrounding an unnamed, high-altitude pond (known informally as Whitebark Pine Moraine Pond) located approximately 3.06 miles NW of Jenny Lake in Grand Teton National Park (GTNP). The main objectives of this study are: 1.) To obtain the precise GPS locations of the current stand of whitebark pine trees in the watershed to generate a GIS map detailing their locations. 2.) To obtain increment cores of a subset of the trees in the watershed to estimate age and date of establishment for the current stand of whitebark pines, with particular attention to fire history. 3.) To analyze ring widths from core samples to identify climatic indicators that may influence the regeneration and survival of whitebark pine.
Freshwater gastropods are a diverse taxa that inhabit a wide variety of freshwater habitats (Lydeard et al. 2004, Strong et al. 2008). Freshwater gastropods often form narrow endemic ranges (Strong et al. 2008) with many species restricted to a single drainage or an isolated spring (Brown et al. 2008). In North America, over 60% of freshwater snails are listed as imperiled or presumed extinct (Lysne et al. 2008). The main factors for the reduction in snail biodiversity are habitat loss, water pollution, and the introduction of invasive species (Strong et al. 2008). Invasive species can dramatically alter the native community by reducing biodiversity and changing ecological processes (Alonso and Castro-Diez 2008). The effects of invasive species on aquatic ecosystems are often permanent and lead to reductions in biodiversity due to predation and competition with native species (Alonso and Castro-Diez 2008, Lysne et al. 2008, Strayer 1999). Invasive gastropods impact native ecosystems by altering carbon and nitrogen levels (Hall et al. 2003, Arango et al. 2009), consuming large amounts of primary producer biomass (Hall et al. 2003, Riley et al. 2008, Strayer 2010), and changing native macroinvertebrate community composition (Kerans et al. 2005, Riley et al. 2008, Cross et al. 2010, Brenneis et al. 2011).
Approximately 50-60% of native sagebrush steppe has been lost to non-native grasses, which has contributed to population decreases for sagebrush-associated songbirds. Removal of non-native grasses and restoration treatments may return structure and function of sagebrush steppe and ultimately benefit songbirds, but their responses must be evaluated. To determine breeding songbird community responses to sagebrush restoration treatments, in 2013 we conducted bird surveys at restored plots at the Kelly Hayfields restoration area in Grand Teton National Park, Wyoming. We compared bird communities and vegetation characteristics in restored plots to plots that were unrestored and to areas of native sagebrush steppe as starting and endpoints for restoration, respectively. Unrestored plots were dominated by non-native grasses; restored plots were dominated by forbs and bare ground and had very little shrub cover (< 0.1%). Native sagebrush plots were dominated by shrubs and native bunchgrasses. Bird community composition was distinct among the three types of plots. Abundance of grassland birds was highest in unrestored plots, and was positively related to cover of non-native grass and litter depth. Abundance of shrubland birds was highest in native sagebrush, and was positively associated with shrub cover. There were very few detections of birds in restored plots, and most species were negatively associated with the high levels of bare ground that characterized these plots. Restored areas may initially (≤5 yrs) provide little breeding bird habitat, which should be accounted for when determining schedules of restoration treatments at Kelly Hayfields.
Few geologists today possess the mountaineering skills to study rocks exposed in the topographically challenging terrain of the Tetons. Even fewer can claim the accomplishment of making the first geologic map of an entire mountain range. One of these pioneering geologists is John C. Reed, Jr., who joined the U.S. Geological Survey in 1953, and who is now scientist emeritus at the U.S. Geological Survey in Denver (Figure 1). In addition to his field geology expertise, Dr. Reed also has a special talent for communicating complex geologic concepts to the public. The purpose of this project was to profile this pioneering mountaineer-geologist and accomplished writer, and to archive his maps, field notes, and photographs for use by future scientists and for the public, particularly park visitors.
In order to understand the distributions and abundances of animals, many environmental factors must be considered, particularly the availability of food resources. Food resources are especially important to nomadic species that move in response to the spatial and temporal availability of these specific food resources that are critical to their survival. An example of such nomadic species is the red crossbill (Loxia curvirostra), which specializes on conifer seeds, a resource that significantly varies both temporally and geographically. Thus, crossbills will move large distances each year to find areas with abundant conifer seeds. While conifer seeds impact the distribution, abundance, and reproductive rate of crossbills, it is likely not the only factor driving these patterns. To truly understand what drives the distribution and abundance of crossbills across North America, further study is needed not only on how external environmental factors such as food abundance affect these patterns, but how tradeoffs among internal physiological processes such as reproduction and survival related processes such as immune function may affect when crossbills irruptively migrate or whether or not reproduction occurs. Historically, research to understand how organisms orchestrate their annual cycles with respect to these costly and conflicting physiological processes has focused narrowly on seasonal breeders that constrain reproduction to times of year when thermoregulatory demand is low (i.e., summer), which provide limited opportunities to reveal how physiological costs of different processes may interact with environmental conditions to influence the evolution of investment strategies. In this study, we are examining how the diversity, abundance, and size of cone crop of conifers influence both 1) the quantity and diversity of red crossbills, as well as 2) their seasonal modulation in investment patterns in reproduction and self-maintenance processes such as immune function in Grand Teton National Park, where crossbills can be found breeding in both summer and winter. Preliminary results from this study have indicated that both conifer diversity and cone crop size affect overall quantity and vocal type diversity of crossbills in Grand Teton National Park, as well as affecting their investment in reproduction and immunity. Overall, results from this study will provide information on how species in general and crossbills, specifically, respond to rapidly changing environments, which has become increasingly important in light of the effects of anthropogenic change.
A significant role of the National Park Service in the United States is the preservation of pristine landscapes. The natural landscape offers the visitor the opportunity to enjoy the wonders of nature and its processes to create beautiful vistas, soaring mountains, and the interplay of vegetation communities. The visitor to the park can be a passive recreationist and observe the landscape or be an active recreationist and experience the landscape through hiking, biking, mountain climbing and a range of other activities. The key linkage between the active and passive recreationist is the landscape that they are experiencing, in one perspective or the other. Any disruption of that natural landscape diminishes the experience. Unfortunately, the perception of the disruption varies with each individual. The trail to get to a scenic vista can be overlooked by some observers, while others believe it is an example of the devastation of human impact.