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Climate change is leading to widespread elevational shifts thought to increase species extinction risk in mountains. We integrate digital elevation models with a metric of human pressure to examine changes in the amount of intact land area available for species undergoing elevational range shifts in all major mountain ranges globally (n = 1010). Nearly 60% of mountainous area is under intense human pressure, predominantly at low elevations and mountain bases. Consequently, upslope range shifts generally resulted in modeled species at lower elevations expanding into areas of lower human pressure and, due to complex topography, encountering more intact land area relative to their starting position. Such gains were often attenuated at high elevations as land-use constraints diminished and topographic constraints increased. Integrating patterns of topography and human pressure is essential for accurate species vulnerability assessments under climate change, as priorities for protecting, connecting, and restoring mountain landscapes may otherwise be misguided., It is often assumed that many species will move upslope in mountainous regions as the climate warms. However, the authors show here that as many species move to higher elevations they will enter areas of lower human footprint but potentially more constraining topography.

Protected areas (PAs) that span elevational gradients enhance protection for taxonomic and phylogenetic diversity and facilitate species range shifts under climate change. We quantified the global protection of elevational gradients by analyzing the elevational distributions of 44,155 PAs in 1,010 mountain ranges using the highest resolution digital elevation models available. We show that, on average, mountain ranges in Africa and Asia have the lowest elevational protection, ranges in Europe and South America have intermediate elevational protection, and ranges in North America and Oceania have the highest elevational protection. We use the Convention on Biological Diversity’s Aichi Target 11 to assess the proportion of elevational gradients meeting the 17% suggested minimum target and examine how different protection categories contribute to elevational protection. When considering only strict PAs [International Union for Conservation of Nature (IUCN) categories I–IV, n = 24,706], nearly 40% of ranges do not contain any PAs, roughly half fail to meet the 17% target at any elevation, and ∼75% fail to meet the target throughout ≥50% of the elevational gradient. Observed elevational protection is well below optimal, and frequently below a null model of elevational protection. Including less stringent PAs (IUCN categories V–VI and nondesignated PAs, n = 19,449) significantly enhances elevational protection for most continents, but several highly biodiverse ranges require new or expanded PAs to increase elevational protection. Ensuring conservation outcomes for PAs with lower IUCN designations as well as strategically placing PAs to better represent and connect elevational gradients will enhance ecological representation and facilitate species range shifts under climate change.

Climatic representation in protected areas—and not just the amount—is critical to safeguarding biodiversity under climate change., Protected areas (PAs) are essential to biodiversity conservation, but their static boundaries may undermine their potential for protecting species under climate change. We assessed how the climatic conditions within global terrestrial PAs may change over time. By 2070, protection is expected to decline in cold and warm climates and increase in cool and hot climates over a wide range of precipitation. Most countries are expected to fail to protect >90% of their available climate at current levels. The evenness of climatic representation under protection—not the amount of area protected—positively influenced the retention of climatic conditions under protection. On average, protection retention would increase by ~118% if countries doubled their climatic representativeness under protection or by ~102% if countries collectively reduced emissions in accordance with global targets. Therefore, alongside adoption of mitigation policies, adaptation policies that improve the complementarity of climatic conditions within PAs will help countries safeguard biodiversity.

Bark beetle outbreaks in the Rocky Mountains caused substantial tree mortality starting in the late 1990s, and continued into the 2000s, with the most severe mortality occurring from 2002 to 2012. Over the same time period, concentrations of dissolved copper in the Big Thompson River (BTR), Colorado, USA, increased significantly and are high enough to negatively affect aquatic life. We examined correlations between dissolved copper and tree mortality in the BTR. Two sites, one consisting of water from the western side of the continental divide and one consisting of water from the eastern side, demonstrated a positive relationship between percentage tree mortality and dissolved copper. The relationships were similar except that the best relationship occurred with a 3-year lag between tree mortality and subsequent dissolved copper levels at the eastern site and with a 5-year lag at the western site. The differential time lag is potentially the result of different levels of carbon in the soil in the watersheds associated with each site because carbon can affect copper mobility. Our results suggest that bark beetle-induced tree mortality may contribute significantly to dissolved copper levels in the BTR.

Ecological niche theory holds that species distributions are shaped by a large and complex suite of interacting factors. Species distribution models (SDMs) are increasingly used to describe species' niches and predict the effects of future environmental change, including climate change. Currently, SDMs often fail to capture the complexity of species' niches, resulting in predictions that are generally limited to climate-occupancy interactions. Here, we explore the potential impact of climate change on the American pika using a replicated place-based approach that incorporates climate, gene flow, habitat configuration, and microhabitat complexity into SDMs. Using contemporary presence-absence data from occupancy surveys, genetic data to infer connectivity between habitat patches, and 21 environmental niche variables, we built separate SDMs for pika populations inhabiting eight US National Park Service units representing the habitat and climatic breadth of the species across the western United States. We then predicted occurrence probability under current (1981-2010) and three future time periods (out to 2100). Occurrence probabilities and the relative importance of predictor variables varied widely among study areas, revealing important local-scale differences in the realized niche of the American pika. This variation resulted in diverse and - in some cases - highly divergent future potential occupancy patterns for pikas, ranging from complete extirpation in some study areas to stable occupancy patterns in others. Habitat composition and connectivity, which are rarely incorporated in SDM projections, were influential in predicting pika occupancy in all study areas and frequently outranked climate variables. Our findings illustrate the importance of a place-based approach to species distribution modeling that includes fine-scale factors when assessing current and future climate impacts on species' distributions, especially when predictions are intended to manage and conserve species of concern within individual protected areas.

In their Letter, You et al. (1) raise concerns about the use of the World Database on Protected Areas (WDPA) (https://www.protectedplanet.net/) in conservation assessments and planning. Their concern arises from potential differences in protected area (PA) delineations and designations between the WDPA and alternate, national PA datasets, citing China’s National Nature Reserves (CNNR) as an example with apparent deviations. You et al. (1) highlight that using the CNNR in calculations of elevational protection yields results that contrast with those published in our original paper (2) using the WDPA. Several issues with You et al.’s (1) analysis prevent a straightforward comparison with … [↵][1]1To whom correspondence should be addressed. Email: pelsen{at}berkeley.edu. [1]: #xref-corresp-1-1

We evaluate the world terrestrial network of protected areas (PAs) for its partnership potential in responding to climate change. That is, if a PA engaged in collaborative, trans-boundary management of species, by investing in conservation partnerships with neighboring areas, what climate change adaptation benefits might accrue? We consider core tenets of conservation biology related to protecting large areas with high environmental heterogeneity and low climate change velocity and ask how a series of biodiversity adaptation indicators change across spatial scales encompassing potential PA and non-PA partners. Less than 1% of current world terrestrial PAs equal or exceed the size of established and successful conservation partnerships. Partnering at this scale would increase the biodiversity adaptation indicators by factors up to two orders of magnitude, compared to a null model in which each PA is isolated. Most partnership area surrounding PAs is comprised of non-PAs (70%), indicating the importance of looking beyond the current network of PAs when promoting climate change adaptation. Given monumental challenges with PA-based species conservation in the face of climate change, partnerships provide a logical and achievable strategy for helping areas adapt. Our findings identify where strategic partnering efforts in highly vulnerable areas of the world may prove critical in safeguarding biodiversity.

Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

North American bat populations face unprecedented threats from disease and rapid environmental change, requiring a commensurate strategic conservation response. Protected‐area networks have tremendous potential to support coordinated resource protection, disease surveillance, and population monitoring that could become a cornerstone of 21st‐century bat conservation. To motivate this idea, we develop a macroecological perspective about bat diversity and associated conservation challenges and opportunities on U.S. National Park Service (NPS) lands. We compared occurrence records from parks against published range maps. Only 55 (19%) of parks reported as present ≥90% of the bat species expected based on range maps, highlighting the information‐gap challenge. Discrepancies suggest substantial under‐reporting and under‐sampling of bats on NPS lands; inadequate range maps and habitat specificity are implicated for some species. Despite these discrepancies, 50 species, including several range‐restricted and endangered taxa, were reported in at least one park unit, including those in the Caribbean and tropical Pacific. Species richness increased with park area at a rate (z) of ~0.1, a pattern confounded by covariation with latitude, elevation, and habitat. When accounting for these factors, richness decreased predictably at higher latitudes and increased at mid‐elevations and with greater numbers of keystone underground habitat structures (caves and mines), reflecting a strong species–energy relationship. The inclusion of covariates that represented percentage of natural vs. human‐modified (converted) landscapes and elevation range—a proxy for environmental heterogeneity—was uninformative. White‐nose syndrome (WNS) presents a tremendous challenge to the NPS: All 12 species currently known to be affected by the disease or to host the causal fungus are represented in the NPS system. One hundred and twenty‐seven NPS parks are in counties currently or likely to become WNS‐positive by 2026. All parks are expected to experience increasing temperatures in coming decades; forecasted climate change velocity is particularly high (>1 SD) for 50 parks. Seventeen parks are in the vicinity of high (>1 SD) wind turbine density. Based on these biogeographic patterns, we suggest ways to prioritize NPS parks for additional inventories, monitoring, and resource protection. Our results demonstrate how macroecology and bioinformatics together can guide strategic conservation capacity‐building among protected areas.

NPS landscape dynamics monitoring project, NPScape; NASA-NPS Landscape Climate Change Vulnerability Project (NASA Applied Sciences program) [10-BIOCLIM10-0034]; United States Geological Survey [G14AC00405]

Forests in the eastern United States have a long history of change related to climate and land use. Eighteen thousand years ago, temperatures were considerably lower and glaciers covered much of the area where deciduous forests currently grow. As glaciers retreated and temperatures rose, tree species advanced from southern areas (Delcourt and Delcourt 1988) and may also have dispersed from low-density populations near the edge of the Laurentide ice sheet (McLachlan, Clark, and Manos 2005). A variety of other processes have also influenced the distribution of tree species. Derechos, tornadoes, and fires cause frequent, small- to intermediate-scale disturbances that are important influences on canopy structure and species composition, while larger disturbances, such as hurricanes, cause less frequent but more extensive changes (Dale et al. 2001).

Only five years ago, Halofsky et al. (2011) wrote: “For climate change adaptation, there is no recipe, no road map, and yet no time to lose; science and management partners must tackle the climate change issue in a timely way, despite uncertainty.” Later that same year, the National Wildlife Federation, in partnership with authors from federal, state, university, and other nongovernmental organizations, published one piece of a road map: Scanning the Conservation Horizon: A Guide to Climate Change Vulnerability Assessment (Glick, Stein, and Edelson 2011). The four steps described in Scanning, introduced in chapter 2, are an excellent introduction to developing and using climate change vulnerability assessments in planning and management of public lands.

Thousands of years before Rocky Mountain National Park was established, people came to the area to experience its beauty and its wildlife and, for many, to re-create themselves. And it remains so today. How do we protect this special place so future generations may have the same opportunities?

The chapters of this book have delved into the timely and important topic of science and management of wildland ecosystems in the face of climate and land use change. The period of the book’s development (2011–2015) was one of rapid advancement in science, policy, agency infrastructure, and understanding of climate change adaptation (chaps. 2, 3, and 13). During this period, evidence of climate change and its consequences was ever more apparent. This was the warmest five-year period on record (http://www.ncdc.noaa.gov). Extreme climate events, such as droughts in California, Amazonia, and Australia, caused fundamental changes in allocating water to people and managing human risk from fire. Evidence of the ecological impacts of climate change became pervasive, including forest die-offs in many parts of the world and massive bleaching of coral ecosystems.

In this chapter, we examine how climate change will likely affect areas of the Great Northern Landscape Conservation Cooperative (Great Northern LCC), but rather than using a fine-filter approach that focuses on a particular species, as has been done in many of the other chapters (e.g., chaps. 9, 10, and 12), we have applied a coarse-filter approach with which we consider our conservation targets to be broader levels of biodiversity. A coarse-filter approach focuses not on an individual species but, rather, on the community that supports a species (Noss 1987) or even on the physical environments as “arenas” of biological activity (Hunter, Jacobson, and Webb 1988). More recently, coarse-filter conservation has been interpreted in a climate change context, in which coarse-filter strategies seek to conserve sites that are minimally affected by climate change (Tingley, Darling, and Wilcove 2014).

Species distribution models are commonly used to predict species responses to climate change. However, their usefulness in conservation planning and policy is controversial because they are difficult to validate across time and space. Here we capitalize on small mammal surveys repeated over a century in Yosemite National Park, USA, to assess accuracy of model predictions. Historical (1900-1940) climate, vegetation, and species occurrence data were used to develop single- and multi-species multivariate adaptive regression spline distribution models for three species of chipmunk. Models were projected onto the current (1980-2007) environmental surface and then tested against modern field resurveys of each species. We evaluated models both within and between time periods and found that even with the inclusion of biotic predictors, climate alone is the dominant predictor explaining the distribution of the study species within a time period. However, climate was not consistently an adequate predictor of the distributional change observed in all three species across time. For two of the three species, climate alone or climate and vegetation models showed good predictive performance across time. The stability of the distribution from the past to present observed in the third species, however, was not predicted by our modeling approach. Our results demonstrate that correlative distribution models are useful in understanding species' potential responses to environmental change, but also show how changes in species-environment correlations through time can limit the predictive performance of models.

In the face of environmental change, species can evolve new physiological tolerances to cope with altered climatic conditions or move spatially to maintain existing physiological associations with particular climates that define each species' climatic niche. When environmental change occurs over short temporal and large spatial scales, vagile species are expected to move geographically by tracking their climatic niches through time. Here, we test for evidence of niche tracking in bird species of the Sierra Nevada mountains of California, focusing on 53 species resurveyed nearly a century apart at 82 sites on four elevational transects. Changes in climate and bird distributions resulted in focal species shifting their average climatological range over time. By comparing the directions of these shifts relative to the centroids of species' range-wide climatic niches, we found that 48 species (90.6%) tracked their climatic niche. Analysis of niche sensitivity on an independent set of occurrence data significantly predicted the temperature and precipitation gradients tracked by species. Furthermore, in 50 species (94.3%), site-specific occupancy models showed that the position of each site relative to the climatic niche centroid explained colonization and extinction probabilities better than a null model with constant probabilities. Combined, our results indicate that the factors limiting a bird species' range in the Sierra Nevada in the early 20th century also tended to drive changes in distribution over time, suggesting that climatic models derived from niche theory might be used successfully to forecast where and how to conserve species in the face of climate change.

We analyzed the relationship between population abundance and variability of western scrub-jays Aphelocoma californica based on 48 yr of Audubon Christmas Bird Counts and the resources on which they depend as indexed by the diversity and abundance of mast-producing oaks and pines and, for California, estimates of acorn production based on a statewide survey. In general, populations of A. c. californica along the Pacific coast were related to oaks, with populations being more abundant and more stable in areas with more oak species and greater oak abundance. In contrast, populations of A. c. woodhouseii in the Great Basin were correlated with pines/conifers, again with higher abundance and greater stability with increased number of pine species and greater abundance of pines/conifers. The presumed driver of these patterns is increased resource abundance with greater habitat abundance and increased resource stability with increasing species diversity due to asynchrony in seed production among different species of trees. Asynchrony in acorn production is particularly high among oaks that require different number of years to produce acorns, but we failed to confirm that populations with access to both types were more stable than those with access to only one type after controlling for oak diversity. However, we did find a strong positive correlation between overall mean scrub-jay abundance in California and overall acorn production one year earlier, suggesting that acorns benefit scrub-jay populations primarily by increasing reproductive success the following year. These patterns demonstrate the strong dependence between population dynamics and resource stability as well as how different these relationships can be within closely related taxa.

Our ability to accurately forecast species' geographical responses to climate change requires knowledge of the proximate and ultimate drivers of their distribution. Here, we consider the ecophysiological and demographic determinants of the distribution of a partial migrant, the North American field sparrow, Spizella pusilla . From 1940 to 1963, the field sparrow extended its winter northern range margin 222 km polewards. Such expansion was coincident with not only a geographical expansion into suitable breeding habitats, but also a decrease in mean abundance across sites occupied during the winter surveys. Combined, these trends suggest that declining populations along the expansion front either stopped migrating or altered their autumn migration. The poleward expansion was not coincident with climatically induced decreases in peak metabolic energy demand, but it did track increases in ecosystem net primary productivity. After 1963, the species' lower lethal temperature prevented further poleward movement. These findings show how different ecophysiological constraints can interact to change migration and distribution in a demographically declining species.

Empirical species distribution models are widely used to predict the effects of climate change on biodiversity distribution but rely on multiple assumptions about the certainty of the locality and climate data. Here, we assess the effect of historical climate data variability when forecasting geographic responses of California mammals to 20th century climate change. We first used two methods to derive gridded climate surfaces from weather station data (ANUSPLIN and PRISM) representing two sampling eras: historic (1900-1940) and current (1980-2005). We then used the two sources of climate data in conjunction with a maximum entropy algorithm (MAXENT) to predict both the historic and current distributions of all major mammal species vouchered historically in California. Results indicate that levels of disagreement between the two climate datasets are considerably greater in the historical era than in the current era. For the bioclimatic variables used in modeling historical mammal distributions, precipitation variables were less concordant than temperature variables. These discrepancies are reflected in the low agreement between historic mammal range predictions and further propagated when the historic models are projected to present day. Nonetheless, some common patterns exist across mammal species and climate estimates. Range stability is the most common prediction between the two eras, followed by expansion and contraction. Jepson ecoregions with relatively high levels of range stability include parts of the Great Central Valley and Sierra Nevada, while other parts of the Central Valley, the Sonoran desert, and Central- and Southwestern California yield predictions of range shifts. Historical species distribution modeling can greatly inform studies attempting to describe how species will continue to move geographically in response to future changes in climate. We suggest that alternative estimates of historical climate and their uncertainties are ultimately required in order to provide a quantitative measure of the confidence in predicted changes in distribution.

Wing loading, defined as the ratio of body mass to wing area, is a critical phenotype affecting flight. In the House Sparrow (Passer domesticus), wing loading is optimized, and both the mean and variation in body mass are inverse functions of ambient temperature. Combined, these relationships predict that climatically induced changes in body mass under optimized wing loading must be countered by directional and variance selection on wing area. Measuring multiple North American House Sparrow populations sampled throughout the 20th century, I show that observed sex-specific changes in the mean and variation in wing length (a close proxy of wing area) are related to changes in winter temperature and quantitatively predicted from a model where wing loading is optimized.

Key to understanding the implications of climate and land use change on biodiversity and natural resources is to incorporate the physiographic platform on which changes in ecological systems unfold. Here, we advance a detailed classification and high-resolution map of physiography, built by combining landforms and lithology (soil parent material) at multiple spatial scales. We used only relatively static abiotic variables (i.e., excluded climatic and biotic factors) to prevent confounding current ecological patterns and processes with enduring landscape features, and to make the physiographic classification more interpretable for climate adaptation planning. We generated novel spatial databases for 15 landform and 269 physiographic types across the conterminous United States of America. We examined their potential use by natural resource managers by placing them within a contemporary climate change adaptation framework, and found our physiographic databases could play key roles in four of seven general adaptation strategies. We also calculated correlations with common empirical measures of biodiversity to examine the degree to which the physiographic setting explains various aspects of current biodiversity patterns. Additionally, we evaluated the relationship between landform diversity and measures of climate change to explore how changes may unfold across a geophysical template. We found landform types are particularly sensitive to spatial scale, and so we recommend using high-resolution datasets when possible, as well as generating metrics using multiple neighborhood sizes to both minimize and characterize potential unknown biases. We illustrate how our work can inform current strategies for climate change adaptation. The analytical framework and classification of landforms and parent material are easily extendable to other geographies and may be used to promote climate change adaptation in other settings.

Climate change will affect not only natural and cultural resources within protected areas but also tourism and visitation patterns. The U.S. National Park Service systematically collects data regarding its 270+ million annual recreation visits, and therefore provides an opportunity to examine how human visitation may respond to climate change from the tropics to the polar regions. To assess the relationship between climate and park visitation, we evaluated historical monthly mean air temperature and visitation data (1979–2013) at 340 parks and projected potential future visitation (2041–2060) based on two warming-climate scenarios and two visitation-growth scenarios. For the entire park system a third-order polynomial temperature model explained 69% of the variation in historical visitation trends. Visitation generally increased with increasing average monthly temperature, but decreased strongly with temperatures > 25°C. Linear to polynomial monthly temperature models also explained historical visitation at individual parks (R2 0.12-0.99, mean = 0.79, median = 0.87). Future visitation at almost all parks (95%) may change based on historical temperature, historical visitation, and future temperature projections. Warming-mediated increases in potential visitation are projected for most months in most parks (67–77% of months; range across future scenarios), resulting in future increases in total annual visits across the park system (8–23%) and expansion of the visitation season at individual parks (13–31 days). Although very warm months at some parks may see decreases in future visitation, this potential change represents a relatively small proportion of visitation across the national park system. A changing climate is likely to have cascading and complex effects on protected area visitation, management, and local economies. Results suggest that protected areas and neighboring communities that develop adaptation strategies for these changes may be able to both capitalize on opportunities and minimize detriment related to changing visitation.

The ultimate success of reintroduction programs for endangered species depends on the ability of reintroduced animals to breed in the wild. We studied the nesting success and breeding biology of a reintroduced population of Puaiohi (Myadestes palmeri) on the island of Kaua'i, Hawaii. Thirty-four captive-bred Puaiohi were released into the Alaka'i Swamp in 1999-2001 and monitored using radiotelemetry. Ten females and two males paired with wild and other released birds, including one polygynous trio. From March to September, 31 nests were built. Mean clutch size was 2.0 eggs, daily nest survival was 0.97 ± 0.01 (mean ± SE) and overall nest success was 0.40 ± 0.02. We confirmed predation, most probably by rats (Rattus spp.), as the greatest cause of nest failure, occurring at 38% of active nests with known fates, and causing the death of two nesting adult females. Ground-based rodent control proved ineffective at protecting nest attempts. Successful nests fledged an average of 1.4 young each (n = 10), and 85% of fledglings survived at least two weeks. Importantly, breeding behavior and success were comparable to those of wild Puaiohi. This is the first record of breeding in the wild from captive-bred endangered Hawaiian passerines. The ability of captive-bred Puaiohi to survive and breed successfully in the wild bodes well for future releases of this and other endangered passerines, but high predation rates on nests and nesting females highlights the importance of maintaining and restoring safe habitat for recovery. Biología y Éxito Reproductivo de una Población Reintroducida de Myadestes palmeri, una Especie en Peligro Crítico

Sudden oak death (SOD), a disease induced by the fungus-like pathogen Phytophthora ramorum , threatens to seriously reduce or eliminate several oak species endemic to the west coast of North America. We investigated how the disappearance of one of these species, coast live oak ( Quercus agrifolia ), may affect populations of five resident oak-affiliated California birds – acorn woodpecker ( Melanerpes formicivorus ), Nuttall’s woodpecker ( Picoides nuttallii ), Hutton’s vireo ( Vireo huttoni ), western scrub-jay ( Aphelocoma californica ), and oak titmouse ( Baeolophus inornatus ) – using geocoded data from Audubon Christmas Bird Counts, North American Breeding Bird Surveys, and the California Gap Analysis. Capitalizing on observed relationships between the focal bird species and both oak species diversity and areal extent, we modeled relative bird abundance while assuming complete loss of Q. agrifolia and complete, partial, or no loss of oak habitat following a disease sweep. Post-SOD projections of bird populations occurring within the range of coast live oak were on average 25–68% smaller and 13–49% more variable relative to pre-SOD estimates. SOD effects were greatest for habitats with low initial oak species diversity. Climatic SOD models predicted that the disease stands to negatively impact populations of all five focal bird species throughout 20% of California’s coast live oak habitats. This study provides the first spatially explicit insights into the potential effects of SOD on avian distribution and abundance. Results may be used to help prioritize conservation plans aimed at minimizing overall community level disturbances resulting from the disease.

We monitored the survival, dispersal, and home-range establishment of captive-bred, reintroduced puaiohi Myadestes palmeri , a critically endangered thrush endemic to the island of Kauai. Fourteen captive-bred, juvenile birds were released from hacktowers in January–February 1999 and monitored for 8–10 weeks using radiotelemetry. All 14 birds (100%) survived to 56 days post-release. Two birds (14.3%) dispersed greater than 3 km from release site within 1 day of release. The remaining birds settled within 1 week and established either temporary home-ranges (mean area=7.9±12.0 ha, range 0.4–31.9) or breeding home-ranges (mean area 1.2±0.34 ha, range 0.8–1.6). Temporary home ranges were abandonded by the beginning of the breeding season, and ultimately 6 of the 14 birds (43%) established breeding home ranges in the release area. The high survival rate bodes well for establishing additional populations through captive breeding and release; however, the 57% dispersal rate out of the target area means that several releases of birds may be necessary in order to repopulate a given drainage. Furthermore, observed dispersal and gene flow between the reintroduced and wild populations have important implications for management of the captive flock.

US national parks are challenged by climate and other forms of broad-scale environmental change that operate beyond administrative boundaries and in some instances are occurring at especially rapid rates. Here, we evaluate the climate change exposure of 289 natural resource parks administered by the US National Park Service (NPS), and ask which are presently (past 10 to 30 years) experiencing extreme (95th percentile) climates relative to their 1901-2012 historical range of variability (HRV). We consider parks in a landscape context (including surrounding 30 km) and evaluate both mean and inter-annual variation in 25 biologically relevant climate variables related to temperature, precipitation, frost and wet day frequencies, vapor pressure, cloud cover, and seasonality. We also consider sensitivity of findings to the moving time window of analysis (10, 20, and 30 year windows). Results show that parks are overwhelmingly at the extreme warm end of historical temperature distributions and this is true for several variables (e.g., annual mean temperature, minimum temperature of the coldest month, mean temperature of the warmest quarter). Precipitation and other moisture patterns are geographically more heterogeneous across parks and show greater variation among variables. Across climate variables, recent inter-annual variation is generally well within the range of variability observed since 1901. Moving window size has a measureable effect on these estimates, but parks with extreme climates also tend to exhibit low sensitivity to the time window of analysis. We highlight particular parks that illustrate different extremes and may facilitate understanding responses of park resources to ongoing climate change. We conclude with discussion of how results relate to anticipated future changes in climate, as well as how they can inform NPS and neighboring land management and planning in a new era of change.

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 degree 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 degrees-4.5 degrees 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.

Resource managers at parks and other protected areas are increasingly expected to factor climate change explicitly into their decision making frameworks. However, most protected areas are small relative to the geographic ranges of species being managed, so forecasts need to consider local adaptation and community dynamics that are correlated with climate and affect distributions inside protected area boundaries. Additionally, niche theory suggests that species' physiological capacities to respond to climate change may be underestimated when forecasts fail to consider the full breadth of climates occupied by the species rangewide. Here, using correlative species distribution models that contrast estimates of climatic sensitivity inferred from the two spatial extents, we quantify the response of limber pine (Pinus flexilis) to climate change in Rocky Mountain National Park (Colorado, USA). Models are trained locally within the park where limber pine is the community dominant tree species, a distinct structural-compositional vegetation class of interest to managers, and also rangewide, as suggested by niche theory. Model forecasts through 2100 under two representative concentration pathways (RCP 4.5 and 8.5 W/m(2)) show that the distribution of limber pine in the park is expected to move upslope in elevation, but changes in total and core patch area remain highly uncertain. Most of this uncertainty is biological, as magnitudes of projected change are considerably more variable between the two spatial extents used in model training than they are between RCPs, and novel future climates only affect local model predictions associated with RCP 8.5 after 2091. Combined, these results illustrate the importance of accounting for unknowns in species' climatic sensitivities when forecasting distributional scenarios that are used to inform management decisions. We discuss how our results for limber pine may be interpreted in the context of climate change vulnerability and used to help guide adaptive management.

Refugia have long been studied from paleontological and biogeographical perspectives to understand how populations persisted during past periods of unfavorable climate. Recently, researchers have applied the idea to contemporary landscapes to identify climate change refugia, here defined as areas relatively buffered from contemporary climate change over time that enable persistence of valued physical, ecological, and socio-cultural resources. We differentiate historical and contemporary views, and characterize physical and ecological processes that create and maintain climate change refugia. We then delineate how refugia can fit into existing decision support frameworks for climate adaptation and describe seven steps for managing them. Finally, we identify challenges and opportunities for operationalizing the concept of climate change refugia. Managing climate change refugia can be an important option for conservation in the face of ongoing climate change.

Background In the mid 20th century, Ernst Mayr and Theodosius Dobzhansky championed the significance of circular overlaps or ring species as the perfect demonstration of speciation, yet in the over 50 years since, only a handful of such taxa are known. We developed a topographic model to evaluate whether the geographic barriers that favor processes leading to ring species are common or rare, and to predict where other candidate ring barriers might be found. Results Of the 952,147 geographic barriers identified on the planet, only about 1% are topographically similar to barriers associated with known ring taxa, with most of the likely candidates occurring in under-studied parts of the world (for example, marine environments, tropical latitudes). Predicted barriers separate into two distinct categories: (i) single cohesive barriers (< 50,000 km2), associated with taxa that differentiate at smaller spatial scales (salamander: Ensatina eschscholtzii; tree: Acacia karroo); and (ii) composite barriers - formed by groups of barriers (each 184,000 to 1.7 million km2) in close geographic proximity (totaling 1.9 to 2.3 million km2) - associated with taxa that differentiate at larger spatial scales (birds: Phylloscopus trochiloides and Larus (sp. argentatus and fuscus)). When evaluated globally, we find a large number of cohesive barriers that are topographically similar to those associated with known ring taxa. Yet, compared to cohesive barriers, an order of magnitude fewer composite barriers are similar to those that favor ring divergence in species with higher dispersal. Conclusions While these findings confirm that the topographic conditions that favor evolutionary processes leading to ring speciation are, in fact, rare, they also suggest that many understudied natural systems could provide valuable demonstrations of continuous divergence towards the formation of new species. Distinct advantages of the model are that it (i) requires no a priori information on the relative importance of features that define barriers, (ii) can be replicated using any kind of continuously distributed environmental variable, and (iii) generates spatially explicit hypotheses of geographic species formation. The methods developed here - combined with study of the geographical ecology and genetics of taxa in their environments - should enable recognition of ring species phenomena throughout the world.

The mission of the United States (US) National Park Service (NPS) is to “conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations” (NPS, 1916). NPS currently manages 397 parks covering about 358,200 km2, or approximately 4% of all US states and territories. The National Park system includes approximately 300 parks that are considered to contain significant natural resources. These parks are key components of a larger network of protected areas that anchor the conservation of natural resources in the US. They also afford direct protection for a number of important and defining resources in the US, including 421 species of threatened or endangered plants and animals, nearly two-thirds of native fishes in the 50 states (Lawrence et al., 2011), the highest point in North America (Mt. McKinley in Denali National Park, 6,194 m), the longest cave system in the world (Mammoth Cave National Park with more than 587 mapped km of caves), the country’s deepest lake (Crater Lake in Crater Lake National Park, 589 m), the lowest terrestrial point in the western hemisphere (Badwater Basin in Death Valley National Park at 86 m below sea level), and – within these extremes – many other natural resources that are significant at local, regional, and national scales.

The ability of species to respond to novel future climates is determined in part by their physiological capacity to tolerate climate change and the degree to which they have reached and continue to maintain distributional equilibrium with the environment. While broad-scale correlative climatic measurements of a species’ niche are often described as estimating the fundamental niche, it is unclear how well these occupied portions actually approximate the fundamental niche per se, versus the fundamental niche that exists in environmental space, and what fitness values bounding the niche are necessary to maintain distributional equilibrium. Here, we investigate these questions by comparing physiological and correlative estimates of the thermal niche in the introduced North American house sparrow (Passer domesticus). Our results indicate that occupied portions of the fundamental niche derived from temperature correlations closely approximate the centroid of the existing fundamental niche calculated on a fitness threshold of 50% population mortality. Using these niche measures, a 75-year time series analysis (1930–2004) further shows that: (i) existing fundamental and occupied niche centroids did not undergo directional change, (ii) interannual changes in the two niche centroids were correlated, (iii) temperatures in North America moved through niche space in a net centripetal fashion, and consequently, (iv) most areas throughout the range of the house sparrow tracked the existing fundamental niche centroid with respect to at least one temperature gradient. Following introduction to a new continent, the house sparrow rapidly tracked its thermal niche and established continent-wide distributional equilibrium with respect to major temperature gradients. These dynamics were mediated in large part by the species’ broad thermal physiological tolerances, high dispersal potential, competitive advantage in human-dominated landscapes, and climatically induced changes to the realized environmental space. Such insights may be used to conceptualize mechanistic climatic niche models in birds and other taxa.

Background Reproductive isolation (RI) is widely accepted as an important "check point" in the diversification process, since it defines irreversible evolutionary trajectories. Much less consensus exists about the processes that might drive RI. Here, we employ a formal quantitative analysis of genetic interactions at several stages of divergence within the ring species complex Ensatina eschscholtzii in order to assess the relative contribution of genetic and ecological divergence for the development of RI. Results By augmenting previous genetic datasets and adding new ecological data, we quantify levels of genetic and ecological divergence between populations and test how they correlate with a restriction of genetic admixture upon secondary contact. Our results indicate that the isolated effect of ecological divergence between parental populations does not result in reproductively isolated taxa, even when genetic transitions between parental taxa are narrow. Instead, processes associated with overall genetic divergence are the best predictors of reproductive isolation, and when parental taxa diverge in nuclear markers we observe a complete cessation of hybridization, even to sympatric occurrence of distinct evolutionary lineages. Although every parental population has diverged in mitochondrial DNA, its degree of divergence does not predict the extent of RI. Conclusions These results show that in Ensatina, the evolutionary outcomes of ecological divergence differ from those of genetic divergence. While evident properties of taxa may emerge via ecological divergence, such as adaptation to local environment, RI is likely to be a byproduct of processes that contribute to overall genetic divergence, such as time in geographic isolation, rather than being a direct outcome of local adaptation.

Niche theory is central to understanding how species respond geographically to climate change. It defines a species' realized niche in a biological community, its fundamental niche as determined by physiology, and its potential niche--the fundamental niche in a given environment or geographic space. However, most predictions of the effects of climate change on species' distributions are limited to correlative models of the realized niche, which assume that species are in distributional equilibrium with respect to the variables or gradients included in the model. Here, I present a mechanistic niche model that measures species' responses to major seasonal temperature gradients that interact with the physiology of the organism. I then use lethal physiological temperatures to parameterize the model for bird species in North and South America and show that most focal bird species are not in direct physiological equilibrium with the gradients. Results also show that most focal bird species possess broad thermal tolerances encompassing novel climates that could become available with climate change. I conclude with discussion of how mechanistic niche models may be used to (i) gain insights into the processes that cause species to respond to climate change and (ii) build more accurate correlative distribution models in birds and other species.

Understanding how hybridization may affect extant and emerging taxa requires knowledge of the origins, viability, and breeding tendencies of hybrid individuals. We examined the geographic and environmental underpinnings of invasion and hybridization among native North American members of the genus Strix. In the early 20th century, the Barred Owl (S. varia) started expanding westward through southern Canada. Since 1973, the species has been invading habitats of the Spotted Owl (S. occidentalism usually displacing but occasionally hybridizing with two Spotted Owl subspecies (S. o. occidentalis and S. o. caurina) to yield viable offspring that often disperse long distances before breeding. Given the high dispersal capabilities of the hybrids, questions remain as to whether hybrid offspring are preferentially colonizing environments that are characteristically different from their natal territories. Further questions surround the proximate origins of the Barred Owl range expansion. We show that the westward range expansion of the Barred Owl was spatiotemporally concomitant with historical increases in summer temperature and that the expansion corridor was positioned at relatively high latitudes because of habitat restrictions. These results provide quantitative support to previous claims that that the Barred Owl range expansion was largely shaped by natural processes. We also show that first filial Barred x Spotted hybrid owls occupy similar environments before and after postnatal dispersal and are randomly distributed both geographically and climatically with respect to parentals. We discuss the climatic mechanisms that may be influencing these dynamics, and conclude with implications for conservation of Strix spp. Received 5 July 2006, accepted 5 February 2007. Resumen.Para entender como la hibridacion puede afectar a taxones existentes y emergentes, se necesita conocer los origenes, la viabilidad y las tendencias de apareamiento de los individuos hibridos. En este trabajo, examinamos las bases geograficas y ambientales de la invasion e hibridacion entre miembros del genero Strix, nativos de Norte America. A principios del siglo 20, S. varia comenzo a expandirse desde el oeste hacia el sur de Canada. Desde 1973, la especie ha invadido habitats de S. occidentalis, generalmente desplazandolo, aunque ocasionalmente hibridando con dos de sus subespecies (S. o. occidentalis y S. o. caurina) y produciendo una progenie viable que normalmente se dispersa a grandes distancias antes de reproducirse. Dada la gran capacidad de dispersion de los hibridos, nos preguntamos si su descendencia coloniza preferentemente ambientes distintos de sus territorios de origen. Cabe tambien preguntarse por el origen de la expansion del rango de S. varia. Nuestros resultados muestran que la expansion de su rango hacia el oeste esta relacionada historicamente con un aumento de las temperaturas estivales; ademas, el corredor de la expansion se localizo a latitudes altas, esto debido a restricciones en el habitat. Estos resultados apoyan cuantitativamente las hipotesis de que la expansion del rango de distribucion de S. varia estuvo determinada por procesos naturales. Ademas, mostramos que los hibridos descendientes del cruce S. varia x S. occidentalis ocupan ambientes similares, tanto climatica como geograficamente, al de los parentales, presentando, ademas, una distribucion aleatoria. Discutimos los mecanismos climaticos que podrian estar influenciando estas dinamicas y concluimos con implicaciones para la conservacion de Strix. 1 E-mail: monahan@berkeley.edu 2Present address: International Rice Research Institute, DAPO 7777, Manila, Philippines.