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At least 91 records · Page 5Linked to original sources

USGS1997

Landscape characteristics of disturbed shrubsteppe habitats in southwestern Idaho (USA)

We compared 5 zones in shrubsteppe habitats of southwestern Idaho to determine the effect of differing disturbance combinations on landscapes that once shared historically similar disturbance regimes. The primary consequence of agriculture, wildfires, and extensive fires ignited by the military during training activities was loss of native shrubs from the landscape. Agriculture created large square blocks on the landscape, and the landscape contained fewer small patches and more large shrub patches than non-agricultural areas. In contrast, fires left a more fragmented landscape. Repeated fires did not change the distribution of patch sizes, but decreased the total area of remaining shrublands and increased the distance between remaining shrub patches that provide seed sources. Military training with tracked vehicles was associated with a landscape characterized by small, closely spaced, shrub patches. Our results support the general model hypothesized for conversion of shrublands to annual grasslands by disturbance. Larger shrub patches in our region, historically resistant to fire spread and large-scale fires because of a perennial bunchgrass understory, were more fragmented than small patches. Presence of cheatgrass (Bromus tectorum), an exotic annual, was positively related to landscape patchiness and negatively related to number of shrub cells. Thus, cheatgrass dominance can contribute to further fragmentation and loss of the shrub patch by facilitating spread of subsequent fires, carried by continuous fuels, through the patch. The synergistic processes of fragmentation of shrub patches by disturbance, invasion and subsequent dominance by exotic annuals, and fire are converting shrubsteppe in southwestern Idaho to a new state dominated by exotic annual grasslands and high fire frequencies.

Idaho↗

USGS2006

Importance of wetland landscape structure to shorebirds wintering in an agricultural valley

Only recently has the influence of landscape structure on habitat use been a research focus in wetland systems. During non-breeding periods when food can be locally limited, wetland spatial pattern across a landscape may be of great importance in determining wetland use. We studied the influence of landscape structure on abundances of wintering Dunlin (Calidris alpina) and Killdeer (Charadrius vociferus) observed on wetlands in the agricultural Willamette Valley of Oregon, USA, during two winters (1999a??2000, 2000a??2001) of differing rainfall. We examined (1) shorebird use within a sample of 100 km2 regions differing in landscape structure (hectares of shorebird habitat [wet, unvegetated]) and (2) use of sites differing in landscape context (area of shorebird habitat within a species-defined radius). For use of sites, we also assessed the influence of two local characteristics: percent of soil exposed and area of wet habitat. We analyzed data using linear regression and information-theoretic modeling. During the dry winter (2000a??2001), Dunlin were attracted to regions with more wetland habitat and their abundances at sites increased with greater area of shorebird habitat within both the site and the surrounding landscape. In contrast, Dunlin abundances at sites were related to availability of habitat at only a local scale during the wet winter (1999a??2000). Regional habitat availability was of little importance in predicting Killdeer distributions, and Killdeer site use appeared unrelated to habitat distributions at both landscape and local scales. Results suggest prioritizing sites for conservation that are located in areas with high wetland coverage.

Landscape Ecology↗

USGS2014

CO 2 and CH 4 emissions from streams in a lake-rich landscape: Patterns, controls, and regional significance

Aquatic ecosystems are important components of landscape carbon budgets. In lake-rich landscapes, both lakes and streams may be important sources of carbon gases (CO 2 and CH 4 ) to the atmosphere, but the processes that control gas concentrations and emissions in these interconnected landscapes have not been adequately addressed. We use multiple data sets that vary in their spatial and temporal extent during 2001–2012 to investigate the carbon gas source strength of streams in a lake-rich landscape and to determine the contribution of lakes, metabolism, and groundwater to stream CO 2 and CH 4 . We show that streams emit roughly the same mass of CO 2 (23.4 Gg C yr −1 ; 0.49 mol CO 2 m −2 d −1 ) as lakes at a regional scale (27 Gg C yr −1 ) and that stream CH 4 emissions (189 Mg C yr −1 ; 8.46 mmol CH 4 m −2 d −1 ) are an important component of the regional greenhouse gas balance. Gas transfer velocity variability (range = 0.34 to 13.5 m d −1 ) contributed to the variability of gas flux in this landscape. Groundwater inputs and in-stream metabolism control stream gas supersaturation at the landscape scale, while carbon cycling in lakes and deep groundwaters does not control downstream gas emissions. Our results indicate the need to consider connectivity of all aquatic ecosystems (lakes, streams, wetlands, and groundwater) in lake-rich landscapes and their connections with the terrestrial environment in order to understand the full nature of the carbon cycle.

Global Biogeochemical Cycles↗

USGS2018

Landscape genetics identifies streams and drainage infrastructure as dispersal corridors for an endangered wetland bird

Anthropogenic alterations to landscape structure and composition can have significant impacts on biodiversity, potentially leading to species extinctions. Population‐level impacts of landscape change are mediated by animal behaviors, in particular dispersal behavior. Little is known about the dispersal habits of rails (Rallidae) due to their cryptic behavior and tendency to occupy densely vegetated habitats. The effects of landscape structure on the movement behavior of waterbirds in general are poorly studied due to their reputation for having high dispersal abilities. We used a landscape genetic approach to test hypotheses of landscape effects on dispersal behavior of the Hawaiian gallinule ( Gallinula galeata sandvicensis ), an endangered subspecies endemic to the Hawaiian Islands. We created a suite of alternative resistance surfaces representing biologically plausible a priori hypotheses of how gallinules might navigate the landscape matrix and ranked these surfaces by their ability to explain observed patterns in genetic distance among 12 populations on the island of O`ahu. We modeled effective distance among wetland locations on all surfaces using both cumulative least‐cost‐path and resistance‐distance approaches and evaluated relative model performance using Mantel tests, a causal modeling approach, and the mixed‐model maximum‐likelihood population‐effects framework. Across all genetic markers, simulation methods, and model comparison metrics, surfaces that treated linear water features like streams, ditches, and canals as corridors for gallinule movement outperformed all other models. This is the first landscape genetic study on the movement behavior of any waterbird species to our knowledge. Our results indicate that lotic water features, including drainage infrastructure previously thought to be of minimal habitat value, contribute to habitat connectivity in this listed subspecies.

Hawai`i↗

USGS2008

Change in the forested and developed landscape of the Lake Tahoe basin, California and Nevada, USA, 1940-2002

The current ecological state of the Lake Tahoe basin has been shaped by significant landscape-altering human activity and management practices since the mid-1850s; first through widespread timber harvesting from the 1850s to 1920s followed by urban development from the 1950s to the present. Consequences of landscape change, both from development and forest management practices including fire suppression, have prompted rising levels of concern for the ecological integrity of the region. The impacts from these activities include decreased water quality, degraded biotic communities, and increased fire hazard. To establish an understanding of the Lake Tahoe basin's landscape change in the context of forest management and development we mapped, quantified, and described the spatial and temporal distribution and variability of historical changes in land use and land cover in the southern Lake Tahoe basin (279 km2) from 1940 to 2002. Our assessment relied on post-classification change detection of multi-temporal land-use/cover and impervious-surface-area data that were derived through manual interpretation, image processing, and GIS data integration for four dates of imagery: 1940, 1969, 1987, and 2002. The most significant land conversion during the 62-year study period was an increase in developed lands with a corresponding decrease in forests, wetlands, and shrublands. Forest stand densities increased throughout the 62-year study period, and modern thinning efforts resulted in localized stand density decreases in the latter part of the study period. Additionally forests were gained from succession, and towards the end of the study period extensive tree mortality occurred. The highest rates of change occurred between 1940 and 1969, corresponding with dramatic development, then rates declined through 2002 for all observed landscape changes except forest density decrease and tree mortality. Causes of landscape change included regional population growth, tourism demands, timber harvest for local use, fire suppression, bark beetle attack, and fuels reduction activities. Results from this study offer land managers within the Lake Tahoe basin and in similar regions a basis for making better informed land-use and management decisions to potentially minimize detrimental ecological impacts of landscape change. The perspective to be gained is based on quantitative retrospection of the effects of human-driven changes and the impacts of management action or inaction to the forested landscape. ?? 2008 Elsevier B.V. All rights reserved.

Forest Ecology and Management↗

USGS2018

Post-wildfire landscape change and erosional processes from repeat terrestrial lidar in a steep headwater catchment, Chiricahua Mountains, Arizona, USA

Flooding and erosion after wildfires present increasing hazard as climate warms, semi-arid lands become drier, population increases, and the urban interface encroaches farther into wildlands. We quantify post-wildfire erosion in a steep, initially unchannelized, 7.5 ha headwater catchment following the 2011 Horseshoe 2 Fire in the Chiricahua Mountains of southeastern Arizona. Using time-lapse cameras, rain gauges, and repeat surveys by terrestrial laser scanner, we quantify the response of a burned landscape to subsequent precipitation events. Repeat surveys provide detailed pre-and post-rainfall measurements of landscape form associated with a range of weather events. The first post-fire precipitation led to sediment delivery equivalent to 0.017 m of erosion from hillslopes and 0.12 m of erosion from colluvial hollows. Volumetrically, 69% of sediment yield was generated from hillslope erosion and 31% was generated from gully channel establishment in colluvial hollows. Processes on hillslopes included erosion by extensive shallow overland flow, formation of rills and gullies, and generation of sediment-laden flows and possibly debris flows. Subsequent smaller rain events caused ongoing hillslope erosion and local deposition and erosion in gullies. Winter freeze-thaw led to soil expansion, likely related to frost-heaving, causing a net centimeter-scale elevation increase across soil-mantled slopes. By characterizing landscape form, the properties of near-surface materials, and measuring both precipitation and landscape change, we can improve our empirical understanding of landscape response to environmental forcing. This detailed approach to studying landscape response to wildfires may be useful in the improvement of predictive models of flood, debris flow and sedimentation hazards used in post-wildfire response assessments and land management, and may help improve process-based models of landscape evolution.

Arizona↗

USGS2016

The evolution of a thermokarst-lake landscape: Late Quaternary permafrost degradation and stabilization in interior Alaska

Thermokarst processes characterize a variety of ice-rich permafrost terrains and often lead to lake formation. The long-term evolution of thermokarst landscapes and the stability and longevity of lakes depend upon climate, vegetation and ground conditions, including the volume of excess ground ice and its distribution. The current lake status of thermokarst-lake landscapes and their future trajectories under climate warming are better understood in the light of their long-term development. We studied the lake-rich southern marginal upland of the Yukon Flats (northern interior Alaska) using dated lake-sediment cores, observations of river-cut exposures, and remotely-sensed data. The region features thick (up to 40 m) Quaternary deposits (mainly loess) that contain massive ground ice. Two of three studied lakes formed ~ 11,000–12,000 cal yr BP through inferred thermokarst processes, and fire may have played a role in initiating thermokarst development. From ~ 9000 cal yr BP, all lakes exhibited steady sedimentation, and pollen stratigraphies are consistent with regional patterns. The current lake expansion rates are low (0 to < 7 cm yr − 1 shoreline retreat) compared with other regions (~ 30 cm yr − 1 or more). This thermokarst lake-rich region does not show evidence of extensive landscape lowering by lake drainage, nor of multiple lake generations within a basin. However, LiDAR images reveal linear “corrugations” (> 5 m amplitude), deep thermo-erosional gullies, and features resembling lake drainage channels, suggesting that highly dynamic surface processes have previously shaped the landscape. Evidently, widespread early Holocene permafrost degradation and thermokarst lake initiation were followed by lake longevity and landscape stabilization, the latter possibly related to establishment of dense forest cover. Partial or complete drainage of three lakes in 2013 reveals that there is some contemporary landscape dynamism. Holocene landscape evolution in the study area differs from that described from other thermokarst-affected regions; regional responses to future environmental change may be equally individualistic.

Alaska↗

USGS2009

Characteristics of vegetation phenology over the Alaskan landscape using AVHRR time-series data

Advanced Very High Resolution Radiometer (AVHRR) satellite data were acquired and composited into twice-a-month periods from 1 May 1991 to 15 October 1991 in order to map vegetation characteristics of the Alaskan landscape. Unique spatial and temporal qualities of the AVHRR data provide information that leads to a better understanding of regional biophysical characteristics of vegetation communities and patterns. These data provided synoptic views of the landscape and depicted phenological diversity, temporal vegetation phenology (green-up, peak of green, and senescence), photosynthetic activity, and regional landscape patterns. Products generated from the data included a phenological class map, phenological composite maps (onset, peak, and duration), and photosynthetic activity maps (mean and maximum greenness). The time-series data provide opportunities to study phenological processes at small landscape scales over time periods of weeks, months, and years. Regional patterns identified on some of the maps are unique to specific areas; others correspond to biophysical or ecoregional boundaries. The data provide new insights to landscape processes, ecology, and landscape physiognomy that allow scientists to look at landscapes in ways that were previously difficult to achieve.

Alaska↗

USGS2002

Does bird community structure vary with landscape patchiness? A Chihuahuan Desert perspective

During the springs of 1995-1997, we studied birds and landscapes at 70 sites in the Chihuahuan Desert to assess relations between bird community structure and landscape patchiness. Within each of two spatial extents (1-kin and 2-km-radius areas centered on each site), we measured the number of patches of individual land-cover types and the total number of patches of all land-cover types. Mean bird richness, and the mean abundance and probability of occurrence of most bird species were significantly correlated with one or more of these variables. Contrary to evidence from other systems, positive association with landscape patchiness did not increase with the degree to which species were habitat generalists, was not negatively related to body size, and did not differ between neotropical migrants and nonmigrants. For the communities' primary constituent species as a group, the strength of positive and negative associations with patchiness did not differ between landscape extents. Within the 1-km but not the 2-km extent, habitat specialists were more positively and negatively associated with patchiness than were habitat generalists. In general, however, neither habitat breadth, body size, nor migratory status seemed to be responsible for associations with landscape patchiness. Mean richness, and the mean abundance and probability of occurrence of most species were significantly correlated with patchiness within one or both extents, and patchiness of all of the most extensive land-cover types was influential. The simplest explanation for most of the bird-patchiness relations we found is that the associations reflected species-specific habitat needs. Through effects on avian richness, abundance, and occurrence, landscape patchiness affected bird community structure. A more complete understanding of the effects of landscape patchiness on bird community structure is likely to emerge when ecologists study the patchiness of major land-cover types at various spatial extents.

Oikos↗

USGS2018

Heterogeneity of a landscape influences size of home range in a North American cervid

In the northeastern United States, chronic wasting disease has recently been detected in white-tailed deer ( Odocoileus virginianus ) populations, and understanding the relationship between landscape configuration and home range may improve disease surveillance and containment efforts. The objectives of our study were to compare size of home range for deer occupying a continuum of forested landscapes and to investigate relationships between size of home range and measures of landscape configuration. We used a movement-based kernel density estimator to estimate home range at five spatial scales among deer across study areas. We developed 7 linear regression models that used measures of the configuration of the forested landscape to explain size of home range. We observed differences in size of home range between sexes among areas that differed based on landscape configuration. We documented size of home range changed with various metrics that identifying connectivity of forested patches. Generally, size of home range increased with an increasing proportion of homogenous forest. Our results suggest that deer in our region occupy a landscape at hierarchically-nested scales that is controlled by the connectivity of the forested landscape across local or broad geographical regions.

Pennsylvania↗

USGS2016

Do geographically isolated wetlands influence landscape functions?

Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bodies to create spatial and temporal heterogeneity in the timing, flow paths, and magnitude of network connectivity. These attributes signal a critical role for GIWs in sustaining a portfolio of landscape functions, but legal protections remain weak despite preferential loss from many landscapes. GIWs lack persistent surface water connections, but this condition does not imply the absence of hydrological, biogeochemical, and biological exchanges with nearby and downstream waters. Although hydrological and biogeochemical connectivity is often episodic or slow (e.g., via groundwater), hydrologic continuity and limited evaporative solute enrichment suggest both flow generation and solute and sediment retention. Similarly, whereas biological connectivity usually requires overland dispersal, numerous organisms, including many rare or threatened species, use both GIWs and downstream waters at different times or life stages, suggesting that GIWs are critical elements of landscape habitat mosaics. Indeed, weaker hydrologic connectivity with downstream waters and constrained biological connectivity with other landscape elements are precisely what enhances some GIW functions and enables others. Based on analysis of wetland geography and synthesis of wetland functions, we argue that sustaining landscape functions requires conserving the entire continuum of wetland connectivity, including GIWs.

Proceedings of the National Academy of Sciences of↗

USGS2013

Circuit theory and model-based inference for landscape connectivity

Circuit theory has seen extensive recent use in the field of ecology, where it is often applied to study functional connectivity. The landscape is typically represented by a network of nodes and resistors, with the resistance between nodes a function of landscape characteristics. The effective distance between two locations on a landscape is represented by the resistance distance between the nodes in the network. Circuit theory has been applied to many other scientific fields for exploratory analyses, but parametric models for circuits are not common in the scientific literature. To model circuits explicitly, we demonstrate a link between Gaussian Markov random fields and contemporary circuit theory using a covariance structure that induces the necessary resistance distance. This provides a parametric model for second-order observations from such a system. In the landscape ecology setting, the proposed model provides a simple framework where inference can be obtained for effects that landscape features have on functional connectivity. We illustrate the approach through a landscape genetics study linking gene flow in alpine chamois (Rupicapra rupicapra) to the underlying landscape.

Journal of the American Statistical Association↗

USGS2002

A landscape ecology approach to assessing development impacts in the tropics: A geothermal energy example in Hawaii

Geographic information systems (GIS) are increasingly being used in environmental impact assessments (EIA) because GIS is useful for analysing spatial impacts of various development scenarios. Spatially representing these impacts provides another tool for landscape ecology in environmental and geographical investigations by facilitating analysis of the effects of landscape patterns on ecological processes and examining change over time. Landscape ecological principles are applied in this study to a hypothetical geothermal development project on the Island of Hawaii. Some common landscape pattern metrics were used to analyse dispersed versus condensed development scenarios and their effect on landscape pattern. Indices of fragmentation and patch shape did not appreciably change with additional development. The amount of forest to open edge, however, greatly increased with the dispersed development scenario. In addition, landscape metrics showed that a human disturbance had a greater simplifying effect on patch shape and also increased fragmentation than a natural disturbance. The use of these landscape pattern metrics can advance the methodology of applying GIS to EIA.

Singapore Journal of Tropical Geography↗

USGS2026

Landscape connectivity and wildlife access to water across an international border: Barriers and opportunities for facilitating transboundary movement

Rapid global acceleration in the construction of physical barriers along international borders has greatly influenced biodiversity and animal movement. Physical barriers can fragment landscapes, hinder access to essential resources, impact long-distance migrations, and inhibit dispersal and gene flow. The effects of physical barriers on animal movement and landscape connectivity can be exacerbated in dryland environments where access to water is a limiting factor. In recent decades, the construction of border barrier infrastructure has accelerated along the international boundary between the United States and Mexico. Here, we used a landscape connectivity model to investigate the effects of barriers on wildlife access to the river in the Lower Rio Grande Valley. We used a modified omnidirectional connectivity model to compare access to the river for three large, terrestrial mammal species across three border barrier scenarios: (1) a landscape without border barriers; (2) a landscape with the existing barrier system; and (3) a potential future landscape with a continuous barrier system. The existing barrier system includes many discrete sections of barrier within tracts of the Lower Rio Grande Valley National Wildlife Refuge or on lands associated with the region's flood control system. Our results indicate that the existing border barriers can impede connectivity and wildlife access to the river in some areas, while some existing gaps between border barrier sections can serve as conduits for wildlife movement and river access. Our future scenario results show how a potential continuous border barrier system could further impede wildlife access to the river. We discuss management and landscape conservation options for enhancing wildlife access to water and riverine habitats. Collectively, our results illustrate the potential effects of border barriers on wildlife movement and access to water, providing information that can be used to better anticipate and lessen the ecological impacts of transboundary barriers.

Tamaulipas, Texas↗

USGS2004

Landscape context moderates edge effects: Nesting success of wood thrushes in Central New York

Despite two decades of research into the effects of habitat fragmentation and edges on nesting birds, critical information about how edges affect the success of natural nests of Neotropical migratory songbirds breeding in heterogeneous landscapes is still missing. We studied abundance and nesting success in Wood Thrushes (Hylocichla mustelina) breeding across a heterogeneous landscape in central New York from 1998 to 2000 to test the hypothesis that edge effects on nesting passerines are stronger in fragmented than contiguous landscapes. We monitored nests to estimate nesting success in edge and interior habitats in both fragmented and contiguously forested landscapes. In contiguous landscapes, daily survival rate did not differ between edge nests (0.963) and interior nests (0.968) (??2 = 0.19, p = 0.66). In contrast, in fragmented landscapes, daily survival estimates were higher in interior (0.971) than edge (0.953) nests (??2 = 3.1, p = 0.08). Our study supports the hypothesis that landscape composition moderates edge effects on actual nests of birds but does not determine the mechanisms causing these patterns.

Conservation Biology↗

USGS2000

Using new video mapping technology in landscape ecology

Biological and ecological monitoring continues to play an important role in the conservation of species, natural communities, and landscapes ( Spellerberg 1991 ). Although resource-monitoring programs have advanced knowledge about natural ecosystems, weaknesses persist in our ability to rapidly transfer landscape-scale information to the public. Ecologists continue to search for new technologies to address this problem and to communicate natural resource information quickly and effectively. New video mapping technology may provide much-needed help. Ecologists realize that only a small portion of large nature reserves can be monitored because of cost and logistical constraints. However, plant and animal populations are usually patchily distributed in subpopulations scattered throughout heterogeneous landscapes, and they are often associated with rare habitats. These subpopulations and rare habitats may respond differently to climate change, land use, and management practices such as grazing, fire suppression, prescribed burning, or invasion of exotic species ( Stohlgren et al. 1997b ). In many national parks, monuments, and wildlife reserves, a few long-term monitoring plots are used to infer the status and trends of natural resources in much larger areas. To make defensible inferences about populations, habitats, and landscapes, it is necessary to extrapolate from a few monitoring plots (local scale) to the larger, unsampled landscape with known levels of accuracy and precision. Recent technological developments have given population biologists and landscape ecologists a unique tool for bridging the data gap between small, intensively sampled monitoring plots and the greater landscape and for transferring this information quickly to resource managers and the public. In this article, we briefly describe this tool, a hand-held video mapping system linked to a geographic information system (GIS). We provide examples of its use in quantifying patterns of native and exotic plant species and cryptobiotic crusts in the new Grand Staircase–Escalante National Monument, Utah, and in surveying aspen clones and regeneration in Rocky Mountain National Park, Colorado.

BioScience↗

USGS2000

Habitat and landscape correlates of presence, density, and species richness of birds wintering in forest fragments in Ohio

We investigated the distribution of wintering woodland bird species in 47 very small, isolated, woodland fragments (0.54-6.01 ha) within an agricultural landscape in north-central Ohio. Our objectives were to determine correlations between temporal, habitat, and landscape variables and avian presence, density, and species richness within the smallest woodlots occupied by such species. Our results suggest that even common species are sensitive to variation in habitat, landscape, and season. Woodlot area explained the most variation in presence, density, and species richness. Shrub cover was also an important predictor variable for presence of the smallest resident birds. Shrub cover might function as both a refuge from predators and as a windbreak, reducing thermal costs in a flat, open landscape. Landscape factors related to isolation and connectedness were also correlated with species presence and density. The species composition of the community changed through the winter, as did the density of individual species, suggesting that the winter season may play an important role in determining the distributions of bird populations across woodlots. The models presented here for Ohio birds in this specific landscape may have biological inference for other species in similar landscapes.

Ohio↗

USGS2005

Linking demographic effects of habitat fragmentation across landscapes to continental source-sink dynamics

Forest fragmentation may cause increased brood parasitism and nest predation of breeding birds. In North America, nest parasitism and predation are expected to increase closer to forest edges because the brood-parasitic Brown-headed Cowbird (Molothrus ater) and generalist nest predators often enter the forest from adjoining developed (largely agricultural) habitats. Yet the abundance of brood parasites and nest predators at the patch scale may be strongly constrained by the total area of developed habitat at landscape scales. The scale and extent of landscape effects are unclear, however, because past studies were mostly conducted within local landscapes rather than across independent landscapes. We report replicated studies from 30 independent landscapes across 17 states of the United States that show that nest parasitism is strongly affected by fragmentation at a 20 km radius scale, equivalent to the maximum foraging range of cowbirds. Nest predation is influenced by both edge and landscape effects, and increases with fragmentation at a 10 km radius scale. Predation is additive to parasitism mortality, and the two together yield decreased population growth potential with increasing forest fragmentation at a 10 km radius scale for 20 of 22 bird species. Mapping of population growth potential across continental landscapes displays broad impacts of fragmentation on population viability and allows geographic prioritization for conservation.

Ecological Applications↗