scholarly journals Urban fox squirrels exhibit habituation to humans but respond to stimuli from natural predators

2020 ◽  
Author(s):  
Anna Kittendorf ◽  
Ben Dantzer
Keyword(s):  
Urban Areas ◽  
Adaptive Response ◽  
Sciurus Niger ◽  
Bird Calls ◽  
Predatory Bird ◽  
Fox Squirrels ◽  
Natural Predator ◽  
Frequent Exposure ◽  
Urban Sites ◽  
Predator Behavior

AbstractAnimals in urban areas that experience frequent exposure to humans often behave differently than those in less urban areas, such as less vigilance or anti-predator behavior. These behavioral shifts may be an adaptive response to urbanization and caused by habituation to humans. A possible negative consequence is cross-habituation to natural predators where urban animals exhibit reduced anti-predator behavior in the presence of humans but also to their natural predators. We tested the hypothesis that habituation to humans in urban populations of fox squirrels (Sciurus niger) causes cross-habituation to stimuli from two possible predators (hawks and domestic dogs). We exposed squirrels in multiple urban and less urban sites to acoustic playbacks of a control stimulus (non-predatory bird calls), a natural predator (hawk), and dogs and recorded their vigilance and three different anti-predator behaviors when a human approached them while either broadcasting one of these three playbacks or no playbacks at all. In trials with no playbacks, urban squirrels exhibited reduced vigilance and anti-predator behavior compared to those in less urban areas but there was little evidence that urbanization altered the correlations among the different behaviors we quantified. Urban squirrels exhibited increased vigilance and anti-predator behavior when exposed to a human paired with hawk playbacks compared to the control playbacks. This indicates that urban squirrels did perceive and assess risk to the natural predator appropriately despite exhibiting habituation to humans. There is currently little evidence that habituation to humans causes animals to lose their fear of natural predators.

Identification of Potential Freight Parking Locations in Urban Areas

2021 ◽  
pp. 036119812110130
Author(s):  
Glenn Vorhes ◽  
Ernest Perry ◽  
Soyoung Ahn
Keyword(s):  
United States ◽  
Information System ◽  
Satellite Imagery ◽  
Urban Areas ◽  
The United States ◽  
Truck Drivers ◽  
Short List ◽  
Automated Processes ◽  
Parking Facilities ◽  
Urban Sites

Truck parking is a crucial element of the United States’ transportation system as it provides truckers with safe places to rest and stage for deliveries. Demand for truck parking spaces exceeds supply and shortages are especially common in and around urban areas. Freight operations are negatively affected as truck drivers are unable to park in logistically ideal locations. Drivers may resort to unsafe practices such as parking on ramps or in abandoned lots. This report seeks to examine the potential parking availability of vacant urban parcels by establishing a methodology to identify parcels and examining whether the identified parcels are suitable for truck parking. Previous research has demonstrated that affordable, accessible parcels are available to accommodate truck parking. When used in conjunction with other policies, adaptation of urban sites could help reduce the severity of truck parking shortages. Geographic information system parcel and roadway data were obtained for one urban area in each of the 10 Mid America Association of Transportation Officials region states. Area and proximity filters were applied followed by spectral analysis of satellite imagery to identify candidate parcels for truck parking facilities within urban areas. The automated processes created a ranked short list of potential parcels from which those best suited for truck parking could be efficiently identified for inspection by satellite imagery. This process resulted in a manageable number of parcels to be evaluated further by local knowledge metrics such as availability and cost, existing infrastructure and municipal connections, and safety.

Urban gardening and spatial justice from a mid-size city perspective: the case of Ortobello Urban Garden

2019 ◽  
pp. 74-90
Author(s):  
Giuseppe Aliperti ◽  
Silvia Sarti
Keyword(s):  
Urban Areas ◽  
Social Dynamics ◽  
Local Community ◽  
Metropolitan Areas ◽  
Participatory Planning ◽  
Spatial Justice ◽  
Urban Gardening ◽  
Negative Impacts ◽  
Urban Sites

The increasing number of metropolitan areas worldwide suggests to more in-depth investigate metropolitan neighbourhoods in order to explain the complex social dynamics emerging in these new contexts. As a matter of fact, the majority of the existing studies on spatial justice provided analyses and investigations focused on metropolitan settings. However, the issue of spatial justice also involves smaller urban areas and further research is needed in that sense. Our investigation analyses a case study of urban gardening that has been developed with the aim of valorising the central neighbourhood of an Italian mid-size city through proposing participatory planning interventions and requalification of urban sites. The urban gardening initiative has included several actors within the process of implementation. The investigated group of people potentially subjected to the spatial injustice is formed by the residents and the local retailers. A comparison between different stakeholders’ perspectives is provided in order to measure the positive and negative impacts of the initiative on the local community.

scholarly journals Spatial distribution of aerosol microphysical and optical properties and direct radiative effect from the China Aerosol Remote Sensing Network

2019 ◽  
Vol 19 (18) ◽  
pp. 11843-11864 ◽  
Author(s):  
Huizheng Che ◽  
Xiangao Xia ◽  
Hujia Zhao ◽  
Oleg Dubovik ◽  
Brent N. Holben ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Optical Properties ◽  
Urban Areas ◽  
Climate Modelling ◽  
Radiative Effect ◽  
Remote Sites ◽  
Fine Mode ◽  
Aerosol Remote Sensing ◽  
Rural Sites ◽  
Urban Sites

Abstract. Multi-year observations of aerosol microphysical and optical properties, obtained through ground-based remote sensing at 50 China Aerosol Remote Sensing Network (CARSNET) sites, were used to characterize the aerosol climatology for representative remote, rural, and urban areas over China to assess effects on climate. The annual mean effective radii for total particles (ReffT) decreased from north to south and from rural to urban sites, and high total particle volumes were found at the urban sites. The aerosol optical depth at 440 nm (AOD440 nm) increased from remote and rural sites (0.12) to urban sites (0.79), and the extinction Ångström exponent (EAE440–870 nm) increased from 0.71 at the arid and semi-arid sites to 1.15 at the urban sites, presumably due to anthropogenic emissions. Single-scattering albedo (SSA440 nm) ranged from 0.88 to 0.92, indicating slightly to strongly absorbing aerosols. Absorption AOD440 nm values were 0.01 at the remote sites versus 0.07 at the urban sites. The average direct aerosol radiative effect (DARE) at the bottom of atmosphere increased from the sites in the remote areas (−24.40 W m−2) to the urban areas (−103.28 W m−2), indicating increased cooling at the latter. The DARE for the top of the atmosphere increased from −4.79 W m−2 at the remote sites to −30.05 W m−2 at the urban sites, indicating overall cooling effects for the Earth–atmosphere system. A classification method based on SSA440 nm, fine-mode fraction (FMF), and EAE440–870 nm showed that coarse-mode particles (mainly dust) were dominant at the rural sites near the northwestern deserts, while light-absorbing, fine-mode particles were important at most urban sites. This study will be important for understanding aerosol climate effects and regional environmental pollution, and the results will provide useful information for satellite validation and the improvement of climate modelling.

A COMPARISON OF PARASITIC HELMINTHS AND ARTHROPODS FROM TWO SUBSPECIES OF FOX SQUIRRELS (SCIURUS NIGER) IN FLORIDA

1996 ◽  
Vol 32 (3) ◽  
pp. 492-497 ◽  
Author(s):  
Donald F. Coyner ◽  
John B. Wooding ◽  
Donald J. Forrester
Keyword(s):  
Sciurus Niger ◽  
Parasitic Helminths ◽  
Fox Squirrels

scholarly journals Daily Activity and Nest Occupation Patterns of Fox Squirrels (Sciurus niger) throughout the Year

PLoS ONE ◽  
2016 ◽  
Vol 11 (3) ◽  
pp. e0151249 ◽  
Author(s):  
Thomas Wassmer ◽  
Roberto Refinetti
Keyword(s):  
Daily Activity ◽  
Sciurus Niger ◽  
Fox Squirrels

A Baylisascaris Outbreak in Fox Squirrels (Sciurus niger) and Subsequent Detection of Francisella tularensis in Kansas, USA

2020 ◽  
Vol 56 (2) ◽  
pp. 457
Author(s):  
Emily C. Vincent ◽  
Mark G. Ruder ◽  
Michael J. Yabsley ◽  
Vincent S. Hesting ◽  
M. Kevin Keel ◽  
...  
Keyword(s):  
Francisella Tularensis ◽  
Sciurus Niger ◽  
Fox Squirrels

scholarly journals Aerosol seasonal variations over urban sites in Ukraine and Belarus according to AERONET and POLDER measurements

2013 ◽  
Vol 6 (6) ◽  
pp. 10731-10759 ◽  
Author(s):  
G. Milinevsky ◽  
V. Danylevsky ◽  
V. Bovchaliuk ◽  
A. Bovchaliuk ◽  
Ph. Goloub ◽  
...  
Keyword(s):  
Optical Thickness ◽  
Seasonal Variations ◽  
Urban Areas ◽  
Late Summer ◽  
Single Scattering ◽  
Aerosol Optical Thickness ◽  
Saharan Dust ◽  
Coarse Mode ◽  
Modal Radius ◽  
Urban Sites

Abstract. The paper presents an investigation of aerosol seasonal variations in several urban sites in the East European region. Our analysis of seasonal variations of optical and physical aerosol parameters is based on the sun-photometer 2008–2012 data from three urban ground-based AERONET sites in Ukraine (Kyiv, Kyiv-AO, and Lugansk) and one site in Belarus (Minsk), as well as on satellite POLDER instrument data for urban areas in Ukraine. Aerosol amount and optical thickness values exhibit peaks in the spring (April–May) and late summer (August), whereas minimum values are seen in late autumn over the Kyiv and Minsk sites. The results show that aerosol fine mode particles are most frequently detected during the spring and late summer seasons. The seasonal variation similarity in the two regions points to the resemblance in basic aerosol sources which are closely related to properties of aerosol particles. However the aerosol amount and properties change noticeably from year to year and from region to region. The analysis of seasonal aerosol optical thickness variations over the urban sites in the eastern and western parts of Ukraine according to both ground-based and POLDER data exhibits the same traits. In particular, over Kyiv, the values of the Angstrom exponent are lower in April of 2011 than in 2009 and 2010, while aerosol optical thickness values are almost the same, which can be explained by an increase in the amount of coarse mode particles in the atmosphere, such as Saharan dust. Moreover, the coarse mode particles prevailed over suburbs and the center of Kyiv during a third of all available days of observation in 2012. In general, the fine and coarse mode particles' modal radii averaged over 2008–2012 range from 0.1 to 0.2 μm and 2 to 5 μm, respectively, during the period from April to September. The single scattering albedo and refractive index values of these particles correspond to a mix of urban-industrial, biomass burning, and dust aerosols. In addition, strongly absorbing particles were observed in the period from October to March, and the modal radius of fine and coarse mode particles changed from month to month widely.

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