Forests in the western U.S. are increasingly impacted by climate change. Warmer and drier conditions both increase fire activity in western forests and make it more difficult for forests to recover after wildfires. If forests fail to recover, they may shift to non-forest ecosystems like grasslands or shrublands. It is important to understand where fires may result in the loss of forests because forests provide a variety of ecosystem services that human communities rely on, including carbon storage, water regulation and supply, and biodiversity. Western forests are also integral for the timber industry and valued for their recreation opportunities. Anticipating future changes to forest ecosystems, particularly at local scales relevant to land and resource managers, requires an understanding of the vulnerability of forests to fire-catalyzed change. The main goal of this work is to create a vulnerability assessment that highlights geographic areas and forest types most vulnerable to fire-catalyzed ecosystem change under current and future climate change scenarios. Researchers will assess the different parts of forest vulnerability, including exposure to varying elements of climate change (e.g. temperature and moisture balance), exposure to varying types of fires (e.g. high vs. low severity fire), and sensitivity of post-fire seedlings to climate-related mortality (e.g. through water stress).  Previous research findings on this topic, funded by the Joint Fire Science Program, the National Science Foundation, and NASA, are directly relevant to land managers, but require “translation” into practical and usable tools and resources. This project will rely on and strengthen communications and collaborations between researchers and federal land managers from the U.S. Forest Service and U.S. Department of the Interior bureaus through face-to-face interactions to ensure that managers have access to the science in a form that is useful. The proposed vulnerability assessment will help managers anticipate when and where wildfires will impact ecosystems in new ways, potentially causing ecosystem shifts from forested to non-forested areas, or to fundamentally different forest types.

Drought events have cost the U.S. nearly $245 billion since 1980, with costs ranging from $2 to $44 billion in any given year. However, these socio-economic losses are not the only impacts of drought. Ecosystems, fish, wildlife, and plants also suffer, and these types of drought impacts are becoming more commonplace. Further, ecosystems that recover from drought are now doing so under different climate conditions than they have experienced in the past few centuries. As temperature and precipitation patterns change, “transformational drought”, or drought events that can permanently and irreversibly alter ecosystems – such as forests converting to grasslands – are a growing threat. This type of drought has cascading implications, including the potential to alter the ability of ecosystems to provide important services to human communities.   Managers of our public lands have expressed a need for baseline science to support their decision-making processes about how to best manage the ecological impacts of drought and drought recovery in the 21st century. By synthesizing the state of the science on transformational drought, researchers will provide managers with a better understanding of the potential for and the future impacts of transformational drought across the country. Researchers will also develop a case study that allows managers to explore how targeted science that is specific to ecological transformation can improve the decision-making process.   The team of scientists will work closely with a group of federal land managers, including from the Bureau of Land Management, U.S. Fish and Wildlife Service, National Park Service, and U.S. Forest Service, to ensure that the project products will support federal efforts to navigate ecological transformation on these lands. Ultimately, this project will provide solutions-oriented science to help resource managers prepare for transformational drought.

Prairies were once widespread across North America, but are now one of the most endangered and least protected ecosystems in the world. Agriculture and residential development have reduced once extensive prairies into a patchwork of remnant prairies and “surrogate” grasslands (e.g., hayfields, planted pastures). Grassland ecosystems and many grassland-dependent birds are also particularly vulnerable to rapid shifts in climate and associated changes in drought and extreme weather.   The Central Flyway is a vast bird migration route that comprises more than half of the continental U.S., and extends from Central America to Canada, and harbors the greatest diversity of grassland birds in North America. Throughout this region, numerous agencies and organizations are entrusted with the management of grassland ecosystems and the species that depend on them in landscapes extensively altered by human activities. Today, they face the additional challenge of managing these ecosystems in the face of a rapidly changing climate.   The goal of this project is to synthesize the vulnerability of grassland ecosystems to climate change across the Central Flyway, with an emphasis on grassland-dependent migratory birds. Researchers will synthesize the state of the science, including providing a robust assessment of how climate variables directly and indirectly (via land use change) affect grassland habitats and migratory bird populations. Researchers will also review current and future adaptation strategies for the conservation of grassland ecosystems and grassland-dependent birds. This effort will result in a synthesis of key management strategies and future research needs related to the conservation of migratory grassland bird populations in the Central Flyway in the face of climate change.

The North Central Climate Adaptation Science Center (NC CASC) partnered with the Wildlife Conservation Society (WCS) and Conservation Science Partners, Inc. (CSP) to systematically identify information gaps that, if addressed, would support management decisions for key species, habitats, or other issues within the North Central region (Montana, Wyoming, Colorado, North Dakota, South Dakota, Nebraska, Kansas). In particular, we were interested in the intersection between 1) high-priority species or habitats that are 2) the subject of a planned decision, and for which 3) climate information would aid decision-making for state and federal agencies. In Spring of 2018, we interviewed state fish and wildlife managers to learn about high-priority species, habitats, and issues within the North Central region. As described in this report, the interviews generated a wealth of information about state agency priorities, and topics for which state managers think more climate change information would be useful.

Abstract (from ScienceDirect): Dryland ecosystems play an important role in determining how precipitation anomalies affect terrestrial carbon fluxes at regional to global scales. Thus, to understand how climate change may affect the global carbon cycle, we must also be able to understand and model its effects on dryland vegetation. Dynamic Global Vegetation Models (DGVMs) are an important tool for modeling ecosystem dynamics, but they often struggle to reproduce seasonal patterns of plant productivity. Because the phenological niche of many plant species is linked to both total productivity and competitive interactions with other plants, errors in how process-based models represent phenology hinder our ability to predict climate change impacts. This may be particularly problematic in dryland ecosystems where many species have developed a complex phenology in response to seasonal variability in both moisture and temperature. Here, we examine how uncertainty in key parameters as well as the structure of existing phenology routines affect the ability of a DGVM to match seasonal patterns of leaf area index (LAI) and gross primary productivity (GPP) across a temperature and precipitation gradient. First, we optimized model parameters using a combination of site-level eddy covariance data and remotely-sensed LAI data. Second, we modified the model to include a semi-deciduous phenology type and added flexibility to the representation of grass phenology. While optimizing parameters reduced model bias, the largest gains in model performance were associated with the development of our new representation of phenology. This modified model was able to better capture seasonal patterns of both leaf area index (R2 = 0.75) and gross primary productivity (R2 = 0.84), though its ability to estimate total annual GPP depended on using eddy covariance data for optimization. The new model also resulted in a more realistic outcome of modeled competition between grass and shrubs. These findings demonstrate the importance of improving how DGVMs represent phenology in order to accurately forecast climate change impacts in dryland ecosystems.

Abstract (from Diversity and Distributions):  Aim Surrogate species can provide an efficient mechanism for biodiversity conservation if they encompass the needs or indicate the status of a broader set of species. When species that are the focus of ongoing management efforts act as effective surrogates for other species, these incidental surrogacy benefits lead to additional efficiency. Assessing surrogate relationships often relies on grouping species by distributional patterns or by species traits, but there are few approaches for integrating outputs from multiple methods into summaries of surrogate relationships that can inform decision‐making. Location Prairie Pothole Region of the United States. Methods We evaluated how well five upland‐nesting waterfowl species that are a focus of management may act as surrogates for other wetland‐dependent birds. We grouped species by their patterns of relative abundance at multiple scales and by different sets of traits, and evaluated whether empirical validation could effectively select among the resulting species groupings. We used an ensemble approach to integrate the different estimated relationships among species and visualized the ensemble as a network diagram. Results Estimated relationships among species were sensitive to methodological decisions, with qualitatively different relationships arising from different approaches. An ensemble provided an effective tool for integrating across different estimates and highlighted the Sora (Porzana carolina), American Avocet (Recurvirostra Americana) and Black Tern (Chlidonias niger) as the non‐waterfowl species expected to show the strongest incidental surrogacy relationships with the waterfowl that are the focus of ongoing management. Main conclusions An ensemble approach integrated multiple estimates of surrogate relationship strength among species and allowed for intuitive visualizations within a network. By accounting for methodological uncertainty while providing a simple continuous metric of surrogacy, our approach is amenable to both further validation and integration into decision‐making.

Globally, spring phenology and abiotic processes are shifting earlier with warming. Differences in the magnitudes of these shifts may decouple the timing of plant resource requirements from resource availability. In riparian forests across the northern hemisphere, warming could decouple seed release from snowmelt peak streamflow, thus reducing moisture and safe sites for dominant tree recruitment. We combined field observations with climate, hydrology, and phenology models to simulate future change in synchrony of seed release and snowmelt peaks in the South Platte River Basin, Colorado, for three Salicaceae species that dominate western USA riparian forests. Chilling requirements for overcoming winter endodormancy were strongest in Salix exigua, moderately supported for Populus deltoides, and indiscernible in Salix amygdaloides. Ensemble mean projected warming of 3.5°C shifted snowmelt peaks 10–19 d earlier relative to S. exigua and P. deltoides seed release, because decreased winter chilling combined with increased spring forcing limited change in their phenology. By contrast, warming shifted both snowmelt peaks and S. amygdaloides seed release 21 d earlier, maintaining their synchrony. Decoupling of snowmelt from seed release for Salicaceae with strong chilling requirements is likely to reduce resources critical for recruitment of these foundational riparian forests, although the magnitude of future decoupling remains uncertain.