Abstract (from IOPScience): Ecological droughts are deficits in soil-water availability that induce threshold-like ecosystem responses, such as causing altered or degraded plant-community conditions, which can be exceedingly difficult to reverse. However, 'ecological drought' can be difficult to define, let alone to quantify, especially at spatial and temporal scales relevant to land managers. This is despite a growing need to integrate drought-related factors into management decisions as climate changes result in precipitation instability in many semi-arid ecosystems. We asked whether success in restoration seedings of the foundational species big sagebrush (Artemisia tridentata) was related to estimated water deficit, using the SoilWat2 model and data from >600 plots located in previously burned areas in the western United States. Water deficit was characterized by: 1) the standardized precipitation-evapotranspiration index (SPEI), a coarse-scale drought index, and 2) the number of days with wet and warm conditions in the near-surface soil, where seeds and seedlings germinate and emerge (i.e. days with 0-5 cm deep soil water potential > -2.5 MPa and temperature above 0 °C). SPEI, a widely used drought index, was not predictive of whether sagebrush had reestablished. In contrast, wet-warm days elicited a critical drought threshold response, with successfully reestablished sites having experienced 7 more wet-warm days than unsuccessful sites during the first March following summer wildfire and restoration. Thus, seemingly small-scale and short-term changes in water availability and temperature can contribute to major ecosystem shifts, as many of these sites remained shrubless two decades later. These findings help clarify the definition of ecological drought for a foundational species and its imperiled semi-arid ecosystem. Drought is well known to affect the occurrence of wildfires, but drought in the year(s) after fire can determine whether fire causes long-lasting, negative impacts on ecosystems.

Throughout western North America, warming associated with climate change is leading to both earlier spring peak streamflows and earlier seed dispersal, potentially reducing seedling establishment and in turn reducing the quality of riparian (near-river) forests, which provide critical habitat for diverse birds, mammals, reptiles, amphibians, and insects, and food and shade for fish and other aquatic animals. This project aimed to predict these effects of climate change on cottonwood and willow tree regeneration in western forests by linking models of seed dispersal timing, streamflow hydrology, and seedling establishment, focusing on the upper South Platte River Basin as a study area. Results are expected to help land managers anticipate future changes in riparian wildlife habitat quality, and potentially to respond to these changes by actively re-vegetating high-priority areas, or by working with water management agencies to schedule dam releases that favor cottonwood and willow establishment.

Climate affects both the demographics of the Greater sage-grouse bird and the condition and long-term viability of their habitats, including sage-steppe communities. This project builds on collaboration among federal land managers, state wildlife biologists, scientists, and other organizations to create a long-term framework for implementing adaptive management for the sage-grouse. The study examined factors that might be limiting grouse numbers and will investigate components of weather patterns in relation to projected climate change models. Precipitation and temperature, as well as variables such as evaporation and soil moisture, will be considered. Overall, the project focused on (1) providing workshops to foster collaboration and interpretation of climate information, (2) developing a sage-steppe habitat map, and (3) suggesting recommendations for an adaptive management framework. 

Determining which species, habitats, or ecosystems are most vulnerable to climate change enables resource managers to better set priorities for conservation action. To address the need for information on vulnerability, this research project aimed to leverage the expertise of university partners to inform the North Central Climate Science Center on how to best assess the vulnerability of elements of biodiversity to climate and land use change in order to inform the development and implementation of management options. Outcomes from this activity were expected to include 1) a framework for modeling vegetation type and species response to climate and land use change, 2) an evaluation of existing alternative vegetation and species response models, and 3) a presentation of vulnerability assessments for managers for incorporation into climate adaptation strategies.

In response to the potential impacts of climate and land use change to the Nation’s ecosystems, the Bureau of Land Management (BLM) launched a series of Rapid Ecoregional Assessments (REAs) in 2010. The REAs are focused on improving our understanding of the current state of ecosystems and how conditions may be impacted by changes in climate, land use, and other stressors.   Researchers with the North Central CSC and the National Oceanic and Atmospheric Administration (NOAA) provided climate science support to the Wyoming Basin REA. The Wyoming Basin REA is a landscape-scale ecological assessment of over 33 million acres in Wyoming, Colorado, Utah, Idaho, and Montana. This region has some of the highest quality wildlife habitat in the Intermountain West, and supports some of the largest U.S. populations of game species, including pronghorn, mule deer, elk, and bighorn sheep. The primary goal of the assessment was to identify potential risks and vulnerabilities of the region’s ecosystems and wildlife to change, to support management decision-making.   The climate analysis found that by 2030, temperatures in the region may rise by 2.5° Fahrenheit, and there will be more extreme hot days and fewer extreme cold days. It’s also expected that the snow accumulation season will start later in the fall, and that changing precipitation patterns will result in wetter winters and drier summers.   The results of this assessment can be used to identify priority areas for conservation or restoration of native plant and animal communities in the region, as well as to support broader landscape-scale decision-making related to all resources and public land uses.  

The goal of this project was to inform implementation of the Greater Yellowstone Coordinating Committee (GYCC) Whitebark Pine (WBP) subcommittee’s “WBP Strategy” based on climate science and ecological forecasting. Project objectives were to: 1. Forecast ecosystem processes and WBP habitat suitability across the Greater Yellowstone Area (GYA) under alternative IPCC future scenarios; 2. Improve understanding of possible response to future climate by analyzing WBP/climate relationships in past millennia; 3. Develop WBP management alternatives; 4. Evaluate the alternatives under IPCC future scenarios in terms of WBP goals, ecosystem services, and costs of implementation; and 5. Draw recommendations for implementation of the GYCC WBP strategy that consider uncertainty. Recommendations were derived in a scenario planning workshop based on both the results and uncertainty in the results. These recommendations are expected to thus be immediately acted upon by the GYA management community and the approach and methods are readily applicable to the several other tree species that are undergoing die-offs under changing climate. 

The Prairie Pothole Region spans parts of North and South Dakota, Minnesota, Montana, Iowa and south-central Canada and contains millions of wetlands that provide habitat for breeding and migrating birds. Because it is the continent’s most important breeding area for waterfowl, conservation and management largely focuses on protecting habitat for nesting ducks. However, other wetland-dependent birds also rely on this region, and it is important to understand the degree to which habitat conserved for ducks provides habitat for other species, and how the quality of this habitat will be affected by climate change. Project researchers tested whether waterfowl are effective representatives, or surrogates, for other wetland-dependent birds by predicting how climate change will affect habitat suitability for waterfowl and other species. The team also considered how climate change is likely to affect land-use patterns and agricultural conversion risk, and used these predictions to identify areas of the landscape where both waterfowl and other species were expected to have suitable habitat in the future. This research was intended to help managers efficiently direct their resources towards conserving areas that will provide habitat to a broad suite of species.

Abstract (from http://www.esajournals.org/doi/abs/10.1890/13-0905.1):  Many protected areas may not be adequately safeguarding biodiversity from human activities on surrounding lands and global change. The magnitude of such change agents and the sensitivity of ecosystems to these agents vary among protected areas. Thus, there is a need to assess vulnerability across networks of protected areas to determine those most at risk and to lay the basis for developing effective adaptation strategies. We conducted an assessment of exposure of U.S. National Parks to climate and land use change and consequences for vegetation communities. We first defined park protected-area centered ecosystems (PACEs) based on ecological principles. We then drew on existing land use, invasive species, climate, and biome data sets and models to quantify exposure of PACEs from 1900 through 2100. Most PACEs experienced substantial change over the 20th century (>740% average increase in housing density since 1940, 13% of vascular plants are presently nonnative, temperature increase of 1°C/100 yr since 1895 in 80% of PACEs), and projections suggest that many of these trends will continue at similar or increasingly greater rates (255% increase in housing density by 2100, temperature increase of 2.5° - 4.5°C/100 yr, 30% of PACE areas may lose their current biomes by 2030). In the coming century, housing densities are projected to increase in PACEs at about 82% of the rate of since 1940. The rate of climate warming in the coming century is projected to be 2.5 - 5.8 times higher than that measured in the past century. Underlying these averages, exposure of individual park PACEs to change agents differ in important ways. For example, parks such as Great Smoky Mountains exhibit high land use and low climate exposure, others such as Great Sand Dunes exhibit low land use and high climate exposure, and a few such as Point Reyes exhibit high exposure on both axes. The cumulative and synergistic effects of such changes in land use, invasives, and climate are expected to dramatically impact ecosystem function and biodiversity in national parks. These results are foundational to developing effective adaptation strategies and suggest policies to better safeguard parks under broad-scale environmental change.

Abstract (from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0070454): Managers of protected natural areas increasingly are confronted with novel ecological conditions and conflicting objectives to preserve the past while fostering resilience for an uncertain future. This dilemma may be pronounced at range peripheries where rates of change are accelerated and ongoing invasions often are perceived as threats to local ecosystems. We provide an example from City of Rocks National Reserve (CIRO) in southern Idaho, positioned at the northern range periphery of pinyon-juniper (P-J) woodland. Reserve managers are concerned about P-J woodland encroachment into adjacent sagebrush steppe, but the rates and biophysical variability of encroachment are not well documented and management options are not well understood. We quantified the rate and extent of woodland change between 1950 and 2009 based on a random sample of aerial photo interpretation plots distributed across biophysical gradients. Our study revealed that woodland cover remained at approximately 20% of the study area over the 59-year period. In the absence of disturbance, P-J woodlands exhibited the highest rate of increase among vegetation types at 0.37% yr - 1. Overall, late-successional P-J stands increased in area by over 100% through the process of densification (infilling). However, wildfires during the period resulted in a net decrease of woody evergreen vegetation, particularly among early and mid-successional P-J stands. Elevated wildfire risk associated with expanding novel annual grasslands and drought is likely to continue to be a fundamental driver of change in CIRO woodlands. Because P-J woodlands contribute to regional biodiversity and may contract at trailing edges with global warming, CIRO may become important to P-J woodland conservation in the future. Our study provides a widely applicable toolset for assessing woodland ecotone dynamics that can help managers reconcile the competing demands to maintain historical fidelity and contribute meaningfully to the U.S. protected area network in a future with novel, no-analog ecosystems.

Abstract (from http://www.sciencedirect.com/science/article/pii/S0006320712002388):  U.S. National Park Service land managers face a variety of challenges to preserving the biodiversity in their parks. A principle challenge is to minimize the impacts of surrounding land use on park condition and biodiversity. In the absence of ideal sets of data and models, the present study develops methods and results that demonstrate a coarse-filter approach to understanding the effects of land use change on habitat types for four pilot study-areas. The area of analysis for each park is defined by a protected-area-centered-ecosystem. Habitat types were defined by biophysical factors assumed to represent the distribution of vegetation communities as they may have existed prior to European settlement. Present-day land use was overlaid on historical habitat and change in area and pattern was quantified for private and public lands separately. Results suggest that patterns of development are affecting study-areas differently. Therefore, the conservation challenges faced by each study-area are distinct to their landscape contexts. For some parks, the primary challenge is to work towards maintaining ecosystem condition in its present or near-present state while paying particular attention to habitats that are underrepresented on public lands. For other parks, the challenge is to address spatially aggregated land use that is affecting only a few habitat types. For still other parks, the challenge is to maintain connectivity with a regional network of protected lands and to undertake restoration projects where feasible. The present methods and results help to focus conservation attention on habitats that have been most impacted by land use change.