Highway Underpasses Research Articles

Highway underpasses offer little fragmentation relief for desert bighorn sheep near Mojave National Preserve, CA

To improve wildlife connectivity across the U.S., managers need to identify and prioritize movement barriers in need of mitigation. Roadway barriers may be semi-permeable and allow some movement either at-grade or via non-wildlife underpasses, but permeability can depend on species-specific behaviors and underpass characteristics. We used a combination of trail cameras and GPS collars to monitor desert bighorn (Ovis canadensis nelsoni) movement near highways and use of non-wildlife underpasses along I-15 and I-40 near Mojave National Preserve, CA. After year 1, we installed guzzlers near target underpasses in a before-after-control-impact (BACI) framework to assess changes in desert bighorn detection over 2 years post-installation. GPS collar data confirmed that desert bighorn moved close enough to 10 of 11 focal underpasses to easily access and use these structures to cross I-15 and I-40. Trail cameras at five sites recorded desert bighorn using habitat very near underpasses and even resting in a culvert tunnel, but no data indicated desert bighorn used underpasses or culverts to cross either highway. Meanwhile, species including coyote (Canis latrans), bobcat (Lynx rufus), and feral burro (Equus asinus) regularly used monitored underpasses. Adding a novel water resource did not significantly increase desert bighorn detection rate on underpass cameras at impact sites relative to control sites after 2 years, and no images suggested bighorn used the installed guzzlers. Patterns of desert bighorn habitat use in the region and lack of observed highway crossings during the study indicate generally low permeability of I-15 and I-40 for this species and a mismatch between non-wildlife underpass locations, design, and desert bighorn behavior.

Establishing the necessary measures for carrying out the activity in security conditions during the execution of work on the Iernut - Chetani highway alignment, Mures county

The purpose of this work is to establish the regime of methane releases (explosive gas) following the execution of the underpass works of the Sibiu-Pitesti highway in the Curtea de Argeș-Pitesti sector. INSEMEX Petroșani executed during the period 01-04.11.2022 on-site measurements at four highway underpasses with a total length of 843m as well as in the areas adjacent to these underpasses, noting that these underpasses are from wells in operation and are connected to the SRM Merișani Station. Based on the measurements and observations made, the analysis of the elements taken into study, as well as the existing records and documentation, INSEMEX Petroșani made the present work.

Hybrid System Analysis for Surface Rainwater Drainage in Urban Highway Underpasses: The Case of Diyarbakir City

Dünyada meydana gelen birçok trafik kazalarındaki “boğulma ölümleri” genellikle karayollarının eğimli alt geçitlerinde veya çöküntülü bölümlerinde meydana gelmektedir. Bir kentsel alanda yer alan karayolu alt geçit noktalarından yağmur suyunun hızlı ve güvenli bir şekilde nasıl uzaklaştırılacağı konusunda artan bir endişe bulunmakla birlikte bu sorunun çözümleri de aranmaktadır. Bu çalışmada Diyarbakır- Şanlıurfa kent içi karayolu üzerinde bulunan altgeçit-köprülü kavşaklardan Doğum Hastanesi Köprülü Kavşağı uygulama alanı olarak seçilmiş olup hem güvenlik hem de hidrolik verimlilik açısından karayolu alt geçidi drenaj sistemini iyileştirmek için yeni bir hibrit sistem tasarımı araştırılmıştır. Bu çerçevede alt geçit drenaj tesisinin iki sistemden oluşması tavsiye edilmektedir. Bu ikili sistem; küçük fırtına olayını yerçekimi yoluyla toplamak için boyutlandırılmış bir yeraltı kanalizasyon hattı ve büyük bir fırtına olayı sırasında fazla suyu drene edecek bir pompa sisteminden oluşmaktadır. Pompa sistemi, acil durumlarda devreye girecek sabit bir istasyon veya hareketli bir birimden oluşmaktadır. Birden fazla fırtına olayı için böyle bir hibrit drenaj sisteminin tasarımında, kanalizasyon borularını ve karter pompalarını boyutlandırmak için sırasıyla kullanılan Rasyonel Metot ve önerilen sistemin performansını iki fırtına olayı altında doğrulamak için benimsenen EPA SWMM bilgisayar modeli olmak üzere iki hidrolojik yaklaşım kullanılmaktadır. Bu araştırmada seçilen alt geçit noktalarındaki hidrolik verimlilik analizleri için bu metotlarla tasarım senaryoları çalışılmıştır. Sonuçlar irdelendiğinde mevcut yağmur suyu drenaj sisteminin olası 5-100 yıllık tekerrür eden yağış olaylarında yetersiz kaldığı görülmüştür. Böylece yapılan simülasyon neticesinde mevcut yağmur suyu drenaj sisteminin kapasitesi artırılmış ve sisteme pompa entegrasyonu sağlanmasıyla yağmur suyu drenaj sistemi kapasitesinin yeterli bir seviyeye geldiği gözlemlenmiştir.

Priodontes maximus (Cingulata: Chlamyphoridae) using a highway wildlife underpass in a fragmented Cerrado landscape from Eastern Goias State, central Brazil

We monitored a stretch of the BR-050 highway in the State of Goias that crosses several natural environments used by the giant armadillo, a peculiar and endangered species whose survival is threatened by vehicle collisions. Here, we present the record of highway underpass use by Priodontes maximus in a fragmented Cerrado landscape in Ipameri, Goias. The finding confirms the use of highway underpasses by the giant armadillo and highlights that these structures should be promoted at points where P. maximus occurs in the habitats isolated by the BR-050.

Ground Settlement Law, Jacking Force Prediction, and Control Countermeasures for Large-Section Rectangular Pipe Jacking of National Highway Underpass

The rectangular pipe jacking method is an efficient, green, trenchless technology for constructing urban underground space. However, some problems, including the high jacking resistance, the instability of the tunneling face, and excessive ground settlement during the large-section rectangular pipe jacking for the underpass of national highways, seriously affect construction safety and traffic. Based on the engineering background of the large-section rectangular pipe jacking in constructing the subway entrance tunnel of Guangzhou Metro Line 7, this work adopts the methods of theoretical calculation, numerical simulation, and engineering application. Five kinds of mechanical models for pipe soil slurry interactions in rectangular pipe jacking are analyzed. An evaluation of the applicability of the jacking force prediction of the different models is conducted. Moreover, the ground settlement law for the large-section rectangular pipe jacking for the underpass of national highways under different influencing factors, including slurry sleeve thickness, grouting pressure, and earth chamber pressure, is revealed. The control countermeasures of the ground settlements, such as installing a waterproof rubber curtain for the tunnel portal, pipe jacking machine receiving techniques, thixotropic slurry for reducing friction resistance, and soil stability at the tunneling face, are carried out. The results show that there is no need to install an intermediate jacking station in the large-section rectangular pipe jacking project with a jacking distance of 63 m. The most reasonable thickness of the thixotropic slurry sleeve is about 150 mm. The most reasonable grouting pressure range is 600–700 kPa. An earth chamber pressure of about 153 kPa is more reasonable to control the soil stability of the tunneling face. The engineering practice shows that the maximum ground settlement of the national highway during jacking is 10 mm. The maintenance effect is excellent, and the traffic operates normally.

Investigation of traffic noise attenuation potential of an urban highway underpass

Road traffic is the main contributor to noise in urban areas. A case of concern is urban highways, due to the intensity of the emitted noise. Acoustic barriers are one of the solutions usually adopted to reduce highway traffic noise in this case. However, they have a negative visual impact on the urban landscape. An underpass could be a solution that provides noise attenuation without introducing aesthetical problems to the urban area. This work investigates the noise attenuation of a highway underpass aiming to confirm its efficiency as a solution for the minimization of traffic noise and explores a variety of scenarios that could influence the noise propagation. Noise measurements and the collection of input data used in noise simulations were conducted at an urban highway located in the city of João Pessoa in Brazil. The investigation was focused on the highway underpass with an L-shaped top edge, which is acting as a parallel acoustic barrier to an adjacent residential area. In addition, simulations were performed using the software SoundPLAN. Five scenarios were simulated: the actual situation and four scenarios with different depths of the underpass and changes on its edge. It was found that the existing L-shape edge of the underpass is positively influential only at points at the immediate vicinity of the border and resulted in an additional average attenuation of 1.3 dB in this region. However, in general, the average attenuation due to the underpass for the points in the whole acoustic shadow zone was 10.6 dB with the actual L-shape edge, and 13.1 dB from simulations when the L-shaped edge was removed. From simulations involving changing the depth of the underpass, it was observed that there was no linear relationship between attenuation versus depth. The simulation results showed that adding an L-shape edge with its current length is not efficient regardless of the depth of the underpass. The results thus confirmed the underpass as an effective solution for the mitigation of highway traffic noise and provided additional insight on the role of the depth associated to changes on the geometry of the top of the underpass.

NOTES ON AN ARTIFICIAL ROOST OF Myotis albescens (CHIROPTERA, VESPERTILIONIDAE) IN SOUTHEASTERN BRAZIL

Myotis albescens has a wide distribution, occurring from southern Mexico to central Argentina and Uruguay, where it is usually caught near streams or flooded areas. M. albescens roosts during the day in cavities such as hollow logs, rock cavities, and buildings. Here, we describe a group of M. albescens roosting in a highway underpass in an Atlantic Forest area in Rancharia, southeastern Brazil. The group was found inside a culvert with a shallow stream passing through it. The animals left the roost and were mist-netted in the first hours of the night. The M. albescens group was composed of 18 individuals, eleven males and seven females. In October, all males had descended testes and two females were pregnant, as confirmed by abdominal palpation. Morphological characters of the specimens fell in the known variation for the species. Our data show that highway underpasses can be important day roosts for bats, especially if riparian areas are preserved

Mule Deer Migrations and Highway Underpass Usage in California, USA

ABSTRACTRoadways may pose barriers to long‐distance migrators such as some ungulates. Highway underpasses mitigate wildlife‐vehicle collisions and can be an important management tool for protecting migration corridors. In northern California, 3 underpasses were built on United States Route 395 (Route 395) in Hallelujah Junction Wildlife Area (HJWA) in the 1970s for a migratory mule deer (Odocoileus hemionus) herd that had been negatively affected by highway traffic. To determine whether these underpasses were still reducing mule deer mortalities >40 years after construction, we investigated deer use of the underpasses from 2006–2019 using cameras, global positioning system (GPS) collars, and roadkill records. We used occupancy models, approximations of GPS‐collared mule deer movement paths, and roadkill locations to estimate the highway crossing patterns of deer. From camera data, there was higher use of the underpasses by deer during migration (spring [Mar–Jun], fall [Oct–Dec]) than in summer (Jul–Sep), when only resident deer were present. Higher underpass usage occurred in the spring compared to fall migrations. Eleven of 21 GPS‐collared migrating mule deer crossed Route 395. We estimated 30% of the crossings (by 7 of the 11 deer) occurred south of the underpasses where deer could easily access the highway because of short (1‐m high) and deteriorating highway fencing. Roadkill data confirmed that deer‐vehicle collisions were occurring south of the underpasses and at the underpasses. This was likely due to deteriorating infrastructure at the underpasses that allows wildlife access to the highway. Overall, our study indicated that although underpasses can provide safe passage for migratory deer decades (>40 yr) after their construction, deteriorating infrastructure such as fencing and gates can lead to wildlife mortalities on highways near underpasses. © 2021 The Wildlife Society.

Echoing Abundance: Public Art and Mutual Aid in Pandemic New Orleans

Echoing AbundancePublic Art and Mutual Aid in Pandemic New Orleans Gwen Dilworth (bio) New Orleans is a city of murals. The walls of the city—stores, abandoned buildings, electric utility boxes, warehouses, highway underpasses—are swathed in images, stories, and dreams for the city. Just as New Orleans has a distinct sound (to me, of trumpets, car horns, feet stomping, the roar under the elevated I-10 highway), it has a similar optical noise that encompasses the visual landscape. Public art tells the story of New Orleans and its people, at every turn. In the weeks after the initial COVID-19 stay-at-home order was issued in New Orleans, the city went quiet. Gone were the cacophonous sounds of Mardi Gras, replaced with an intense, reverberating quiet. Even Bourbon Street was empty; the city had transformed into a ghost town overnight. New Orleans was struggling. The virus was spreading rapidly across Louisiana, and cases in the city were some of the highest in the nation. The stark inequalities in New Orleans were painfully laid bare for all to see. The underfunded public health infrastructure in the city couldn’t support rising cases. COVID-19 was spreading at rapid speed in jails and prisons. Houseless individuals had no place to isolate. Hopelessness was leaking out everywhere, and the quiet in the city was resounding. Six months later, in December, driving down Washington Avenue near Cajun Seafood, a bright mural emerged in my line of sight. It stands a story high, covering the side of the Fast Stop Meat Market and overlooking an empty parking lot. Three bright fists—blue, purple, and pink—rise out of an alligator-occupied garden. Butterflies flit between the clenched fists, and beneath it, a banner waves, reading: “The People United Will Never Be Defeated” (Figure 1). Observing the mural, completed by artist Zac Maras in July, one can almost hear the echoes of the protests that wrapped through the streets this summer and fall. Following the horrific killing of George Floyd, [End Page 97] protests shattered the reverberating quiet in New Orleans, and residents poured into the streets to advocate for a city without policing, alongside protections for workers, accessible healthcare, and an end to evictions. The butterflies, darting between saturated fists, appear as a symbol of the transformation that might grow from the fertile ground of protest. Maras’s mural stands as a testament to the people of New Orleans coming together to envision and demand change, arms outstretched, united. Click for larger view View full resolution Figure 1. Zac Maras, The People United Will Never Be Defeated, 2020, mural, Washington Avenue, New Orleans. Photograph by the author. New Orleans is, of course, no stranger to catastrophe or hardship. Nor is it a stranger to the values that have kept the city afloat during difficult times: community, care, and connection. New Orleans has a long history of mutual aid, centered around historically Black Mutual Aid and Pleasure Clubs. As the pandemic has reinforced long-existing inequalities in the city, new systems of care have formed to support New Orleans’ most vulnerable residents. Since the pandemic began in March, mutual aid networks have erupted in New Orleans, filling the gaps in community needs and giving neighbors the tools to support one another. These networks have emerged as Facebook groups for individuals to offer or request aid, organizations making and distributing meals to houseless [End Page 98] individuals, and individuals sharing plants and seeds for others to grow their own food. Mutual aid is a political act, not a charitable one. Mutual aid is a project of community care and collective liberation, of working cooperatively to meet the needs of one’s community. Like in many cities across the nation, mutual aid in New Orleans has developed as a radical alternative to abandonment, hopelessness, and despair. Mutual aid operates on the principle that we have the skills and resources to care for one another even when our government can not or will not, and that these acts of care can serve to cultivate abundance and community. These projects begin the work of building a new world where everyone has enough. In New Orleans, public art...

Use of unfenced highway underpasses by lowland tapirs and other medium and large mammals in central-western Brazil

Wildlife road mortality is a worldwide problem. In tropical developing countries, it is urgent to implement and test mitigation measures to reduce wildlife-vehicle collisions, especially because financial resources are limited and alternatives should be considered such as retrofitting of existing underpasses. We assessed herein the use of 12 unfenced crossing structures, including drainage culverts and cattle boxes, by medium and large mammals along a highway in the Brazilian Cerrado. Underpass usage was monitored for 3682 trapping nights from September 2017 to May 2018. We recorded 20 species of medium and large wild mammals in a total of 4212 events. The most frequent mammals were lowland tapirs (Tapirus terrestris, n=1154), followed by capybaras (Hydrochoerus hydrochaeris, n=910), and crab-eating foxes (Cerdocyon thous, n=271). Underpass usage did not differ between drainage culverts and cattle boxes, but species composition differed among the structures, suggesting that terrestrial mammals prefer cattle boxes while some semiaquatic species used only culverts. We identified 28 different individual tapirs using the underpasses and we estimated over 180 tons of tapir biomass crossing under the highway. Tapir underpass usage did not differ between cattle boxes and culverts, but it was negatively associated with the presence of pasture area around the structures. Our study suggests that, although underpasses show high mammal usage suggesting a satisfactory level of connectivity, combining this method with fencing would be critical to substantially decrease wildlife road mortality and increase human safety.

Hybrid Drainage Design for Highway Underpass

AbstractDrowning fatalities in traffic accidents often occur at roadway sag curves or depressed sections. An increasing concern is how to quickly and safely remove the stormwater from low points of...

Wildlife Interactions within Highway Underpasses

ABSTRACTHighway underpasses are a common management tool used to lessen wildlife‐vehicle collisions on roadways. Despite their widespread use, the effects of predator‐prey interactions and human disturbances on wildlife within underpasses have not been well studied. To understand the effect of species interactions and human disturbances on wildlife traveling through underpasses, we analyzed camera data from 3 underpasses in Hallelujah Junction Wildlife Area, Sierra County, California, USA, from June 2017 to December 2018. We recorded 3,589 detections, which were predominately mule deer (Odocoileus hemionus), rodents, lagomorphs, California quail (Callipepla californica), bobcats (Lynx rufus), mountain lions (Puma concolor), and coyotes (Canis latrans). We used occupancy modeling and daily activity estimates to analyze species' spatial and temporal activity within the underpasses. Predator‐prey interactions and human disturbances were among the most important factors that influenced wildlife travel through the underpasses. Mule deer avoided underpasses highly used by mountain lions, and mountain lions followed mule deer daily temporal activity patterns and seasonal activity patterns. These results indicate that predator‐prey interactions influenced deer and mountain lion use of the underpasses. Coyotes favored underpasses and seasons with higher rodent and lagomorph presence, suggesting that the presence of prey was also important to coyote use of the underpasses. Coyotes, mountain lions, and bobcats all exhibited either temporal or spatial avoidance of human activity within the underpasses. California quail avoided predators within the underpasses and favored underpasses and times with high human activity. Our study suggests that underpass managers need to closely monitor the effect of predator‐prey interactions and human activity on wildlife within underpasses to ensure these interactions do not discourage wildlife from using them. © 2019 The Wildlife Society.

Trans-national conservation and infrastructure development in the Heart of Borneo.

The Heart of Borneo initiative has promoted the integration of protected areas and sustainably-managed forests across Malaysia, Indonesia, and Brunei. Recently, however, member states of the Heart of Borneo have begun pursuing ambitious unilateral infrastructure-development schemes to accelerate economic growth, jeopardizing the underlying goal of trans-boundary integrated conservation. Focusing on Sabah, Malaysia, we highlight conflicts between its Pan-Borneo Highway scheme and the regional integration of protected areas, unprotected intact forests, and conservation-priority forests. Road developments in southern Sabah in particular would drastically reduce protected-area integration across the northern Heart of Borneo region. Such developments would separate two major clusters of protected areas that account for one-quarter of all protected areas within the Heart of Borneo complex. Sabah has proposed forest corridors and highway underpasses as means of retaining ecological connectivity in this context. Connectivity modelling identified numerous overlooked areas for connectivity rehabilitation among intact forest patches following planned road development. While such ‘linear-conservation planning’ might theoretically retain up to 85% of intact-forest connectivity and integrate half of the conservation-priority forests across Sabah, in reality it is very unlikely to achieve meaningful ecological integration. Moreover, such measure would be exceedingly costly if properly implemented–apparently beyond the operating budget of relevant Malaysian authorities. Unless critical road segments are cancelled, planned infrastructure will fragment important conservation landscapes with little recourse for mitigation. This likelihood reinforces earlier calls for the legal recognition of the Heart of Borneo region for conservation planning as well as for enhanced tri-lateral coordination of both conservation and development.

Conservation implications for jaguars and other neotropical mammals using highway underpasses.

The Nuevo Xcan-Playa del Carmen highway in Quintana Roo, bisects the vegetation corridor connecting two Jaguar Conservation Units (JCUs): Yum Balaam (north) and Sian Ka´an (south). The project´s main goal was to describe differential use of available crossing structures (wildlife underpasses and culverts) by mammals present along this highway. We set 28 camera traps along the 54km stretch of the highway covering wildlife underpasses (10), and culverts such as box culverts (9) and pipes (9) from September 2016 until March 2017. A total of 24 jaguar crossings have been recorded exclusively using wildlife underpasses, including four males and two females. At least 18 other mammal species including five of the target priority species (protected by Mexican law) were documented, all of which were native except for two invasive species. In terms of species using the crossing structures, we identified 13 species using wildlife underpasses, nine using concrete box culverts and 10 using concrete pipes. Wildlife underpasses show higher diversity values (Shannon´s exponential index = 5.8 and Inverse Simpson´s index = 4.66) compared to culverts because they allow bigger species to cross. We recommend more highways along the jaguar´s distribution should develop mitigation measures to allow for wildlife connectivity. Wildlife underpasses, along with retrofitted culverts, could help secure not only the permanence of this species by facilitating the functional connectivity between populations but have positive impacts on other neotropical mammalian fauna as well.

Three-Dimensional Virtual Highway Model for Sight-Distance Evaluation of Highway Underpasses

When it comes to the safe design and operation of highways, sight distance is of utmost importance. The estimation of sight distance must be performed taking the three-dimensional (3D) nature of roadways and related features into account. Horizontal curves and crest vertical curves were the common sight restrictions considered in highway design. However, overhanging features may also affect sight distance. This paper presents a 3D virtual model for evaluating sight distance on sites where overpass structures restrict sight distance and for detecting sight-distance-related issues. The procedure and inputs for the computation of sight distance are described as are the results, which were validated and applied to a case study of an in-service highway underpass. Stopping sight distance and passing sight distance were evaluated for a section of highway with specific sight-distance characteristics of overpasses. The effect of the observer and target heights on sight distance for underpasses proved the opposite of those on horizontal curves and crests. Near an overpass, the heights should be switched from those used on curves and crests to evaluate stopping and passing sight distance according to operational and safety criteria. Finally, the currently existing passing zones were evaluated by means of the results obtained, revealing possible deficiencies in the establishment of passing zones.

Differential use of highway underpasses by bats

Roads can form barriers to movement for many species, and may reduce the ability of individuals to access foraging and breeding habitat. The impacts of roads on terrestrial fauna has been well studied, however little is known of the impact of roads on insectivorous bats. Wildlife crossing structures (e.g. fauna underpasses) may reduce the barrier impacts of roads and improve connectivity across roads. Use of underpasses by wildlife likely varies among species depending on their movement behaviour. In this study, we investigated whether the flight patterns of insectivorous bats influenced their use of underpasses. We monitored bat activity under and above 6 open-span bridges, 6 box culverts and 6 unmitigated sites along a major highway in Australia. We used Poisson regression models within a Bayesian framework of inference to compare the activity of 12 bat species (grouped into three guilds based on their flight patterns: clutter-adapted, edge-adapted, and open-adapted species) under the structures, over the road above the structures, above unmitigated segments of the highway, and in the vegetation adjacent to the roads. Bats were less active above the road than they were in the surrounding vegetation or under bridges. Two of the three guilds (i.e. seven species) crossed the highway more under bridges than they did under culverts or by going over the road, which suggests that bridges may reduce barrier effects of the road better than culverts. Installing bridges instead of culverts may better reduce the impacts of roads on multiple insectivorous bats species with a single structure type.

Native Wildlife Use Of Highway Underpasses In A Desert Environment

Abstract While highway underpasses and culverts are often identified in conservation planning as wildlife corridors, their success at facilitating connectivity in deserts has rarely been tested. We evaluated wildlife use of seven, pre-existing highway underpass structures and four associated canyon sites over 29 mo to identify spatial and temporal wildlife use patterns and to assess factors that may constrain wildlife use, particularly for native carnivore species. Our results indicate that a wide diversity of wildlife species utilize the underpass structures including rodents, lagomorphs, deer, and carnivores. Structural attributes of the underpasses have a minor influence on use by most observed species, although structural characteristics and human activity both contributed to determining bobcat (Lynx rufus) usage. Wildlife and human diel patterns differed between the underpass sites and their associated canyons. We suggest that providing a range of underpass structures to support use by a diversity of...

Weather conditions associated with autumn migration by mule deer in Wyoming.

Maintaining ecological integrity necessitates a proactive approach of identifying and acquiring lands to conserve unfragmented landscapes, as well as evaluating existing mitigation strategies to increase connectivity in fragmented landscapes. The increased use of highway underpasses and overpasses to restore connectivity for wildlife species offers clear conservation benefits, yet also presents a unique opportunity to understand how weather conditions may impact movement of wildlife species. We used remote camera observations (19,480) from an existing wildlife highway underpass in Wyoming and daily meteorological observations to quantify weather conditions associated with autumn migration of mule deer in 2009 and 2010. We identified minimal daily temperature and snow depth as proximate cues associated with mule deer migration to winter range. These weather cues were consistent across does and bucks, but differed slightly by year. Additionally, extreme early season snow depth or cold temperature events appear to be associated with onset of migration. This information will assist wildlife managers and transportation officials as they plan future projects to maintain and enhance migration routes for mule deer.

Ephemeral Gods and Billboard Saints: Don DeLillo'sUnderworldand Urban Apparitions

In this essay, I examine the hyper-modern apparition with which Don DeLillo concludesUnderworldalongside a “real-life” image, said to look like the Virgin Mary, which appeared in April 2005 in Chicago on the wall of a highway underpass. I argue that discussing these two apparitions together highlights how both images transform urban surfaces and waste, creating new sites around which collectivities take shape. The pairing also illustrates the mode of perception that the apparitions engender, one that makes urban realities of class dispossession and minority displacement visible. Drawing upon Walter Benjamin's notion of the wish image and Merleau-Ponty's concept of “perceptual faith,” I argue that these apparitions evoke the otherworldly but ultimately insist upon the material dimensions of urban life.

Use of highway underpasses by bandicoots over a 7-year period that encompassed road widening

Roads may create filters or barriers to animal movement and adversely affect population processes. Underpasses are now commonly installed during highway construction to mitigate barrier effects and link habitat patches. We used sand-tracking to investigate use of six underpasses by bandicoots along a section of the Pacific Highway in northern New South Wales before, during and after road duplication (i.e. expansion from two to four lanes). Trapping revealed that the northern brown bandicoot (Isoodon macrourus) and the long-nosed bandicoot (Perameles nasuta) were equally abundant prior to highway expansion. Five years before highway widening, bandicoots frequently used 18-m-long underpasses (>1 traverses per day). Twelve months before road widening, underpass use by bandicoots declined to ~0.5 traverses per day and continued near this level during construction. This declined to 0.03 traverses per day after duplication with underpasses extended to ≥49 m in length. Few crossings were recorded after expansion of the road corridor, which may indicate a shift from regular foraging traverses before duplication to infrequent dispersal movements after duplication.