scholarly journals Human-dominated land cover corresponds to spatial variation in Mourning Dove (Zenaida macroura) reproductive output across the United States

The Condor ◽  
2020 ◽  
Vol 122 (2) ◽  
Author(s):  
David Muñoz ◽  
David Miller

Abstract Studies examining impacts of land cover typically focus on abundance, distribution, and/or community richness, overlooking underlying demographic processes such as survival or reproduction. Here, we present findings from a unique dataset that allowed us to measure the relationship between land cover and reproductive output across the distribution of the Mourning Dove (Zenaida macroura). We used hunter-derived, Mourning Dove wing data across 1,271 counties in the United States from 2008 to 2014 to estimate spatially explicit age ratios (juveniles: adults), an index of local reproductive output. We also used raster imagery data to estimate relationships between reproductive output and land cover and crop cover. We found that low reproductive output occurs in regions where Mourning Dove declines have been steepest. Our findings reveal that impacts of land cover vary geographically, but even at a coarse resolution, small changes in the relative proportion of human-dominated landscapes can have a significant impact on the reproductive output of this generalist species. Maize and soybean systems correlate with up to a 57% reduction in Mourning Dove reproductive output in the eastern United States. In the western United States, developed areas correlate with a 41% increase in reproductive output. Across the United States, native habitats had neutral or negative relationships with age ratios. Our study contributes continental-scale evidence that Mourning Dove reproductive output is largely driven by human-dominated land cover including agricultural and residential areas. With Mourning Doves declining across the range, discerning more fine-scale land cover factors is critical for ensuring Mourning Dove populations persist into the future.

Author(s):  
Jonathan M Winter ◽  
Trevor F Partridge ◽  
Dorothy Wallace ◽  
Jonathan W Chipman ◽  
Matthew P Ayres ◽  
...  

Abstract The prevalence of Lyme disease and other tick-borne diseases is dramatically increasing across the United States. While the rapid rise in Lyme disease is clear, the causes of it are not. Modeling Ixodes scapularis Say (Acari: Ixodidae), the primary Lyme disease vector in the eastern United States, presents an opportunity to disentangle the drivers of increasing Lyme disease, including climate, land cover, and host populations. We improved upon a recently developed compartment model of ordinary differential equations that simulates I. scapularis growth, abundance, and infection with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) by adding land cover effects on host populations, refining the representation of growth stages, and evaluating output against observed data. We then applied this model to analyze the sensitivity of simulated I. scapularis dynamics across temperature and land cover in the northeastern United States. Specifically, we ran an ensemble of 232 simulations with temperature from Hanover, New Hampshire and Storrs, Connecticut, and land cover from Hanover and Cardigan in New Hampshire, and Windsor and Danielson in Connecticut. Consistent with observations, simulations of I. scapularis abundance are sensitive to temperature, with the warmer Storrs climate significantly increasing the number of questing I. scapularis at all growth stages. While there is some variation in modeled populations of I. scapularis infected with B. burgdorferi among land cover distributions, our analysis of I. scapularis response to land cover is limited by a lack of observations describing host populations, the proportion of hosts competent to serve as B. burgdorferi reservoirs, and I. scapularis abundance.


2021 ◽  
Vol 37 (1_suppl) ◽  
pp. 1626-1651
Author(s):  
John E Lens M.EERI ◽  
Mandar M Dewoolkar ◽  
Eric M Hernandez M.EERI

This article describes the approach, methods, and findings of a quantitative analysis of the seismic vulnerability in low-to-moderate seismic hazard regions of the Central and Eastern United States for system-wide assessment of typical multiple span bridges built in the 1950s through the 1960s. There is no national database on the status of seismic vulnerability of bridges, and thus no means to estimate the system-wide damage and retrofit costs for bridges. The study involved 380 nonlinear analyses using actual time-history records matched to four representative low-to-medium hazard target spectra corresponding with peak ground accelerations from approximately 0.06 to 0.3 g. Ground motions were obtained from soft and stiff site seismic classification locations and applied to models of four typical multiple-girder with concrete bent bridges. Multiple-girder bridges are the largest single category, comprising 55% of all multiple span bridges in the United States. Aging and deterioration effects were accounted for using reduced cross-sections representing fully spalled conditions and compared with pristine condition results. The research results indicate that there is an overall low likelihood of significant seismic damage to these typical bridges in such regions, with the caveat that certain bridge features such as more extensive deterioration, large skews, and varied bent heights require bridge-specific analysis. The analysis also excludes potential damage resulting from liquefaction, flow-spreading, or abutment slumping due to weak foundation or abutment soils.


2003 ◽  
Vol 13 (1) ◽  
pp. 63-70 ◽  
Author(s):  
Zhiqiang Gao ◽  
Jiyuan Liu ◽  
Xiangzheng Deng

2016 ◽  
Vol 13 (5) ◽  
pp. 456-476 ◽  
Author(s):  
Lauren Copley Sabon

In response to increasing Latino new destination migration in the United States, Latino sex trafficking networks have emerged in many of these areas. This article examines victimization experiences of Latina immigrants trafficked by a regional network operating in the Eastern United States drawn from law enforcement records and interviews with legal actors involved in the criminal case. The stories shared with law enforcement by the Latina victims gives insight into their lives, experiences in prostitution, and the operation of a trafficking/prostitution network (all lacking in the literature). Through the analytical frame of social constructionism, this research highlights how strict interpretation of force, fraud, coercion, and agency used to define “severe forms of trafficking” in the TVPA limits its ability to recognize many victimization experiences in trafficking situations at the hands of traffickers. The forms of coercion used in the criminal enterprise under study highlights the numerous ways it can be wielded (even without a physical presence) and its malleability as a concept despite legal definitional rigidity. The lack of legal recognition of the plurality of lived experiences in which agency and choice can be mitigated by social forces, structural violence, intersectional vulnerabilities, and the actions of others contributes to the scholarly critique of issues prosecuting trafficking cases under the TVPA and its strict legal definitions.


1998 ◽  
Vol 78 (1) ◽  
pp. 155-165 ◽  
Author(s):  
Suzanne I. Warwick ◽  
David A. Wall

A review of biological information is provided for Erucastrum gallicum (Willd.) O.E. Schulz. A European native, it was introduced into Canada and the United States in the early 1900s and spread rapidly along the railroads. The species occurs in all the provinces and the Northwest Territories and is particularly abundant in the Prairie provinces and mid-western United States. It is a summer annual, rarely a winter annual or biennial species, and is characterized by high reproductive output. Plants occur most commonly on waste ground and along roadsides and railroads, followed by agricultural fields. Erucastrum gallicum is of allopolyploid origins (n = 15, 7 + 8 chromosomes), and contains a single multi-locus isozyme genotype. The species is a close relative of Brassica and is capable of limited genetic exchange with the canola species, B. rapa and B. napus. The possible transfer of genes from transgenic canola varieties to Erucastrum gallicum poses a remote, but potential, environmental risk. Populations of Erucastrum gallicum, including both Old World and North American populations, constitute a valuable germplasm resource as potential sources of beneficial agronomic traits, such as disease resistance for canola crop improvement. Key words: Dog mustard, Erucastrum gallicum, weed biology, risk assessment, germplasm, canola


1981 ◽  
Vol 71 (1) ◽  
pp. 321-334
Author(s):  
Robin K. McGuire ◽  
Theodore P. Barnhard

abstract The accuracy of stationary mathematical models of seismicity for calculating probabilities of damaging shaking is examined using the history of earthquakes in China from 1350 A.D. to 1949 A.D. During this time, rates of seismic activity varied periodically by a factor of 10. Probabilities of damaging shaking are calculated in 62 cities in North China using 50 yr of earthquake data to estimate seismicity parameters; the probabilities are compared to statistics of damaging shaking in the same cities for 50 yr following the data window. These comparisons indicate that the seismic hazard analysis is accurate if: (1) the maximum possible earthquake size in each seismogenic zone is determined from the entire seismic history rather than from a short-time window; and (2) the future seismic activity can be estimated accurately. The first condition emphasizes the importance of realistically estimating the maximum possible size of earthquakes on faults. The second indicates the need to understand possible trends in seismic activity where these exist, or to develop an earthquake prediction capability with which to estimate future activity. Without the capability of estimating future seismicity, stationary models provide less accurate but generally conservative indications of seismic ground-shaking hazard. In the United States, the available earthquake history is brief but gives no indication of changing rates of activity. The rate of seismic strain release in the Central and Eastern United States has been constant over the last 180 yr, and the geological record of earthquakes on the southern San Andreas Fault indicates no temporal trend for large shocks over the last 15 centuries. Both observations imply that seismic activity is either stationary or of such a long period that it may be treated as stationary for seismic hazard analyses in the United States.


2018 ◽  
Vol 374 (1763) ◽  
pp. 20170394 ◽  
Author(s):  
Daniel S. Park ◽  
Ian Breckheimer ◽  
Alex C. Williams ◽  
Edith Law ◽  
Aaron M. Ellison ◽  
...  

Phenology is a key biological trait that can determine an organism's survival and provides one of the clearest indicators of the effects of recent climatic change. Long time-series observations of plant phenology collected at continental scales could clarify latitudinal and regional patterns of plant responses and illuminate drivers of that variation, but few such datasets exist. Here, we use the web tool CrowdCurio to crowdsource phenological data from over 7000 herbarium specimens representing 30 diverse flowering plant species distributed across the eastern United States. Our results, spanning 120 years and generated from over 2000 crowdsourcers, illustrate numerous aspects of continental-scale plant reproductive phenology. First, they support prior studies that found plant reproductive phenology significantly advances in response to warming, especially for early-flowering species. Second, they reveal that fruiting in populations from warmer, lower latitudes is significantly more phenologically sensitive to temperature than that for populations from colder, higher-latitude regions. Last, we found that variation in phenological sensitivities to climate within species between regions was of similar magnitude to variation between species. Overall, our results suggest that phenological responses to anthropogenic climate change will be heterogeneous within communities and across regions, with large amounts of regional variability driven by local adaptation, phenotypic plasticity and differences in species assemblages. As millions of imaged herbarium specimens become available online, they will play an increasingly critical role in revealing large-scale patterns within assemblages and across continents that ultimately can improve forecasts of the impacts of climatic change on the structure and function of ecosystems. This article is part of the theme issue ‘Biological collections for understanding biodiversity in the Anthropocene’.


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