Installation Of Fences Research Articles

Complex interactions of deer herbivory, soil chemistry, and competing vegetation explain oak–hickory forest tree regeneration in central Pennsylvania, USA

The root causes of forest tree regeneration failure are difficult to resolve, although numerous studies show ungulate herbivory, soil conditions, and competition from undesirable vegetation as likely contributors. To better understand the relative importance of each issue, we conducted a 7-year manipulative experiment to assess the interactive effects of white-tailed deer ( Odocoileus virginianus) herbivory, soil acidity, and competing vegetation on tree regeneration in oak–hickory forests of central Pennsylvania, USA. Outcomes depended on initial tree seedling abundance, and all three factors had significant interactions. At low initial seedling abundance, fencing resulted in the greatest increase, but all treatments had a positive effect on seedling growth and abundance. At higher initial seedling abundance, abundance failed to recover 7 years after herbicide treatment and soil pH was an important predictor. When soil pH was >4.6 from lime application, seedling growth and abundance in unfenced controls with high initial abundance was comparable to the fenced-only treatment. Competing vegetation, assumed to be a symptom of excessive, long-term deer herbivory, does not seem to be the primary factor limiting tree regeneration in our study area. Ameliorating acid deposition warrants greater consideration as a management action because it could provide long-lasting benefits compared to short-term fence installations.

Economic estimates of invasive wild ungulate damage to livestock producers in Hawai'i.

Invasive ungulates (hoofed mammals), including deer, feral pigs, feral goats, and feral sheep, are known to cause damage to agriculture, property, natural resources, and many other commodities. Most of the information regarding the economic impacts of wild ungulates is from North America, where some of these species are native. To evaluate invasive ungulate damage to livestock producers in the Hawaiian Islands, which have no native ungulates, a survey was distributed to livestock producers across the state. Survey results described how total annual costs are distributed among damage, control, and repairs for survey respondents, who represented a significant percentage of total ranchland acreage across the islands. The estimates, excluding fixed fence installation, revealed an annual cost to livestock producers who responded to the survey of US$1.42 million, which ranged from $3.6 million to $7.5 million when extrapolated to the entire state. The large cost contributors included damage to property, pastureland repair, control costs (excluding fencing), supplemental feed, and predation of calves by wild pigs. Additionally, producers reported spending more than $2 million in upfront fence installation costs. Most of these costs were reported by respondents on the islands of Hawai'i and Moloka'i. Study results revealed substantial damage to state livestock producers due to wild ungulates and are useful in determining an invasive ungulate management strategy that can appropriately aid the most impacted sectors of Hawai'i. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Odor Fences Have No Effect on Wild Boar Movement and Home Range Size.

Wild boars are an opportunistic wildlife species that has successfully colonized the human-modified landscape in Europe. However, the current population boom has negative consequences, which result in a rapid increase in human-wildlife conflicts and disease transmission, including African swine fever (ASF). The increasing frequency of conflicts requires adequate solutions for these issues through various measures. Application of deterrents is a common non-lethal measure whose effects have been insufficiently verified until recently. Thus, this study aims to evaluate the effectiveness of odor fences, often applied as a barrier against wild boar movement. For this purpose, 18 wild boars were marked with GPS collars. After 22 days of initial monitoring, 12 sections of odor fences were installed on their home ranges. The monitored wild boars crossed the area 20.5 ± 9.2 times during the pre-installation period and 19.9 ± 8.4 times after the odor fence installation. Moreover, the average home range varied between 377.9 ± 185.0 ha before and 378.1 ± 142.2 ha after the odor fence installation. Based on GPS telemetry results, we do not support using odor repellent lines for crop protection or for limiting wild boar movement to lessen ASF outbreaks.

Installation of a Pit Fence in Cramped Conditions

The construction of buildings and structures in cramped conditions requires a special approach from hydraulic engineers and builders, requiring the preservation of the surrounding development in a working condition. This circumstance requires a geotechnical forecast of deformations of objects falling into the zone of geotechnical influence of the construction of a building under construction at the design stage and then the organization and implementation of geotechnical monitoring of deformations as a result of construction and installation work. It should be noted that the objects of the surrounding development can be in different categories of technical condition. According this circumstance the permissible deformations may be different. In any geotechnical case, there is an urgent need to install excavation fences that perform a dual task: both ensuring the stability of the soil walls, and reducing the impact of the new construction object on existing buildings. The determination of the bearing capacity of the enclosing structures of the excavation, especially the retaining soil anchors themselves, is of great importance in modern geotechnical construction. The engineering method used in this article to determine the bearing capacity of drilling-injection anchors with sufficient accuracy for technical calculations showed the convergence of calculated and real values based on the results of static tests.

Large-Scale Performance Evaluation of Various Woven Silt Fence Installations under Nebraska Highway Conditions

Sediment barriers are used on construction sites to protect downstream waterbodies from the impacts of sediment-laden stormwater runoff. Although ubiquitous on construction sites, many sediment barrier practices lack performance-based testing to determine effectiveness and treatment mechanisms, with previous evaluations being limited to conditions local to the Southeastern U.S., with conditions in other regions remaining untested. Testing was conducted to determine the effectiveness of woven silt fence barriers and provide structural improvements to common installation methods. Testing was conducted using a large-scale sediment barrier testing apparatus at the Auburn University—Stormwater Research Facility. The results from testing indicate that Nebraska DOT standard silt fence installations can be improved to reduce the risk of structural failures such as undermining, complete installation failure, slow dewatering, and overtopping. To improve structural performance, four modifications (a 15.2 cm [6 in.] offset trench, wooden posts, a dewatering board with an overflow weir, and a dewatering board with an overflow weir with adjusted post spacing) were tested. On average, 83% of introduced sediment was retained behind the tested barriers. The water quality results across the testing of standard and modified installations indicated that stormwater treatment was due to sedimentation within the impoundment formed by silt fence installations and not filtration through geotextile fabric.

The design of removable railings in tunnel crossings on highways

During the operation of the tunnel crossing, to maintain its required technical condition, preventive and repair work is carried out, with the exception of track work, by forces and means of the track distance.When servicing tunnel crossings, compliance with safety regulations for people, as well as the established mode of train traffi c, must be ensured. To ensure the necessary conditions for the operation and repair of technological equipment, technological service platforms, mezzanines, stairs with non-removable railings are arranged at intersections. When using non-removable or bulky guards during maintenance and repair work at tunnel crossings on highways, the safe movement of vehicles and people is quite problematic.In cramped tunnel conditions, instead of fences having a welded structure, it is proposed to use a removable railing structure that will not interfere with the movement of railway transport and ensure the safety of work processes. The removable railing device includes: a fastening plate, a fastening bracket into which the railing plate is installed.The main parameters of removable railings are determined. The sequence of installation of a replaceable fence is described.The use of removable railings in the enclosing structures will ensure the passage of vehicles, taking into account the requirements for the safety of working processes at tunnel crossings without disturbing the train traffic.

Assessing mammal fence crossing and local fence management in relation to classical swine fever spread in Japan.

Infectious diseases at the wildlife-livestock-human interface have become a crucial issue, and evidence-based measures are growing increasingly important. One countermeasure against animal diseases in wildlife is using fencing to contain and reduce disease spread and transmission rates between wild populations; however, quantitative assessments on fencing are rare. Moreover, existing research on fencing has highlighted knowledge gaps on the social and ecological aspects relevant to the use and design of fences. To control the spread of classical swine fever, fences were installed from the east to west in Gifu Prefecture, Japan, by March 2019, with the aim of restricting wild boar movement. To clarify the process of installation and maintenance of the fences, we conducted semi-structured interviews with prefectural government officers in Gifu Prefecture. Additionally, we installed infrared-triggered cameras at fence locations with and without gaps to evaluate the fence permeability of mammals. We used a generalized linear mixed model to evaluate the relationship between the presence of gaps and the relative abundance and permeability of each mammal. Our findings showed that the occurrence of gaps was inevitable during the installation and management of wide-area perimeter fence in Japan, partly because of social factors. For example, fences could not be installed on roads that were frequently used by residents and were not adequately maintained owing to budgetary reasons in some cases. Analysis of footage from the infrared-triggered cameras revealed that several mammal species crossed the fence at gaps and even had the ability to cross the gapless parts of the fences. Wild boars crossed through the gaps regularly. It is possible that Sika deer, Japanese serows, raccoons, Japanese badgers, raccoon dogs, Japanese macaques, and feral cats crossed through fence gaps because their relative abundance was high at gap locations. In contrast, Japanese hares slipped through the fence mesh rather than crossing through the gaps. In conclusion, we suggest that coordination and collaboration among related parties, a sufficient supply of fence materials, and securing a budget for fence maintenance are important for fence installation and maintenance. Furthermore, as fence gaps are inevitable, technical development of countermeasures for these gaps could be effective.

Predicting Suitable Areas for African Swine Fever Outbreaks in Wild Boars in South Korea and Their Implications for Managing High-Risk Pig Farms.

African swine fever (ASF) is a highly contagious disease affecting domestic pigs and wild boars, with no effective vaccine or treatment available. In South Korea, extensive measures have been implemented to prevent ASF transmission between wild boars and ASF spillover from wild boars to pig farm sectors, including the search for ASF-infected carcasses in mountainous forests and the installation of fences across wide areas of these forests. To determine the priority search range for infected carcasses and establish pig farm-centered quarantine measures, it is necessary to predict the specific path of ASF outbreaks in wild boars and identify pig farms at high risk of ASF spillover from wild boars. Here, we aimed to predict suitable areas and geographical paths for ASF outbreaks in wild boars using the MaxEnt model and shortest-path betweenness centrality analysis. The analysis identified a high frequency of ASF outbreaks in areas with a suitability value ≥0.4 on the suitability map and in areas within a 1.8 km range from the path on the shortest-path map, indicating these areas were high-risk zones for ASF outbreaks. Among the 5063 pig farms analyzed, 37 were in the high-risk zone on the suitability map, 499 were in the high-risk zone on the shortest-path map, and 9 were in both risk zones. Of the 51 pig farm sectors with a dense distribution of pig farms (kernel density ≥ 8), 25 sectors were in contact with or partially overlapped the high risk zone on the suitability map, 18 sectors were located within the high risk zone on the shortest-path map, and 14 sectors were located within both risk zones. These findings aided in determining the priority range for searches for wild boar carcasses and enabled the establishment of preemptive ASF prevention measures around the pig farming sectors that are at risk of ASF spillover from wild boars.

Hotspots and hotmoments of wildlife roadkills along a main highway in a high biodiversity area in Brazilian Amazonia

ABSTRACT Wildlife roadkills have become a concern in the Amazon biome due to the opening of major roads in recent decades. In this study, we aimed to describe wildlife roadkills in a 100-km stretch of the BR-163 highway, in western Pará state, determining which vertebrate groups are most affected and whether there are spatial (hotspots) and temporal (hotmoments) aggregations of roadkills. From July 2019 to June 2020, we carried out 25 surveys at 15-day intervals, from a vehicle at a maximum speed of 40 km h-1. We recorded 351 individuals at an observed rate of 0.14 ind km-1 day-1. Despite their lower detectability and faster carcass removal rate from the road due to small size, most recorded roadkills were amphibians (0.066 ind km-1 day-1). We mapped several hotspots along the study stretch considering the total number of animals recorded, and separately for amphibians and reptiles. Multiple linear regression analyses indicated that the number of roadkills of all vertebrates, amphibians and reptiles recorded are influenced by temperature and precipitation. Information on places with the highest incidence of roadkills can support actions such as the installation of underpasses and fences, aimed at reducing the impacts on wild vertebrates of this Amazonian highway.

Improving the Design and Performance of Double-Row Sediment Barriers Used During Highway Construction

Sediment barriers (SBs) are stormwater management devices often installed along the perimeter of a construction site to intercept and treat overland sediment-laden flow before discharge into the surrounding environment. Effective SB practices remove stormwater pollutants by creating a temporary impoundment upstream of the practice which facilitates sediment capture via sedimentation. Controlling agencies and design practitioners often specify the installation of two SB practices (i.e., primary and secondary SB) in areas where enhanced stormwater treatment is critical because of downstream environmental concerns (e.g., impaired waters). This study sought to identify the overall performance of a commonly specified double-row SB (i.e., double-row silt fence), as well as six alternative designs that utilized various secondary SB practices that could be easily paired with a primary silt fence SB. Small-scale experiments were conducted on each of these double-row design configurations to develop a comprehensive understanding of their performance capabilities. A statistical analysis conducted on 700 water quality data points suggests that all six alternative double-row designs significantly outperformed the double-row silt fence installation. Water quality improvements achieved using alternative secondary SBs ranged from 11% to 71% during the 30 min test period and 14% to 60% during the 90 min dewatering period. In comparison, the double-row silt fence installation only achieved 5% and 1%, respectively. Additionally, post-test observations of secondary SB cross sections indicate that, at best, only half of the matrix filter media within the secondary SB contacts sediment-laden flow. This observation suggests that alternative cross-sectional designs could improve media utilization.

Electrified fencing as a mitigation strategy for human-elephant conflict in Western Serengeti: Community perspectives

Human-wildlife conflict (HWC) is a serious threat to communities living proximal to wildlife areas. Understanding the attitudes of local communities toward HWC management is critical for planning and designing effective and sustainable mitigation strategies. Here we used quasi-structured questionnaires to assess local community attitudes toward the electrified fencing installed in the Western Corridor of the Serengeti Ecosystem to mitigate human-elephant conflict (HEC). We found that most of the respondents agreed that the installed electrified fence effectively mitigates HEC. In addition, fencing has been perceived as effective in controlling problematic or dangerous animals other than elephants, and therefore increasing harvest yields, improving the physical security of farms and properties, minimizing illegal hunting, and reducing interaction between domestic and wild animals. Furthermore, the local people in the surveyed area expect that human-wildlife coexistence will improve after the fence installation. As the area is famously known for the annual great wildebeest migration, we recommend further studies on the ecological impacts of the installed fence.

First biological data, associated fauna, and microclimate preferences of the enigmatic cave-dwelling beetle Dalyat mirabilis Mateu, 2002 (Coleoptera, Carabidae)

Dalyat mirabilisis an extraordinary troglobite carabid described in 2002 from the cave Simarrón II in the southeast of the Iberian Peninsula (Spain). A new subfamily Dalyatinae was erected to accommodate this species with remarkable morphological characters and adaptations to live underground. In addition to the former original descriptions, there is only one more study and it aimed to elucidate its evolutionary history. Its closest living relative belongs to the genusPromecognathusin North America and both groups seem to have diverged sometime in the late Jurassic to early Cretaceous. In this work, the phenology ofD. mirabilis, its associated invertebrate fauna and the environmental conditions of the cave Simarrón II were studied for a full year cycle. This carabid is not evenly distributed in the cave, in time or space. It is most abundant during the winter months, wet season, and it disappears from the top layer of the substrate in the summer. A positive correlation was found between the number of carabids captured per trap and the distance to the entrance of the cave; most specimens were captured in traps farthest from the entrance and located in the chamber known as Vias Salas Negras. Furthermore, several spatially-resolved analyses integrating relative humidity, temperature, and the number of captures per trap showed thatD. mirabilisprefers Vias Salas Negras for having a higher and more stable relative humidity than other chambers in the cave. Larvae were never captured, regardless of intense efforts to collect them for years. Finally, 30 other invertebrate species belonging to 12 different Orders were captured in the cave and are listed here, 25.8% are troglobites, 29.0% troglophiles and 45.2% troglexenes. The data from this study was used for an initiative to protect this cave and its remarkable fauna. Some of the measures taken by the Administration include the control of human visits to the cave, the installation of a perimetral fence surrounding the entrance, and the installation of an informative panel at the exterior of the cave describing the endemic entomological fauna it contains.

Numerical study on snow erosion and deposition around an embankment with a snow fence under snowfall conditions

Snow drift which usually occurs in conjunction with snowfall can significantly alter the distribution pattern of snow cover around roads creating travel hazards for vehicles. To study the snow distribution around a road and evaluate the snow prevention efficiency of snow fence, based on the theories of two-phase flow and snowdrift erosion and deposition, a numerical model is developed. The model includes snowfall during snow drift, spatial distribution characteristics of wind speed and snow phase volume fraction, and dynamic changes of snow drift shape on the ground during drifting. We simulate the distribution characteristics of snowdrift around an embankment without and with the protection of a snow fence and under the conditions of no snowfall and snowfall. The results indicate that snow deposition is greatest on the leeward side of the embankment in comparison to the windward side of the embankment and takes a longer time to reach equilibrium. On the leeward side of the embankment, the snow accumulation rate under the condition of snow falling is higher than that under the condition of no snow falling. Nonetheless, the two conditions both suggest that installation of the snow fence intercepts a large amount of snow behind the snow fence, decreases the snow phase volume fraction near the ground, and reduces the snowdrift accumulation on the leeward side of the embankment within a certain period.

A Nature-Based Solution for Coastal Protection: Wind Tunnel Investigations on the Influence of Sand-Trapping Fences on Sediment Accretion

Sand-trapping fences are a frequently used nature-based solution in coastal protection for initiating and facilitating coastal dune toe growth. However, only a few researchers have evaluated the trap efficiency of sand-trapping fences based on their porosity and height. Subsequently, the design of their properties has only been based on empirical knowledge, to date. However, for restoring and maintaining coastal beach–dune systems, exact knowledge of sand-trapping fence’s optimal properties is essential. Thus, we conducted physical model tests focusing on the most crucial parameters: fence height (h = 40, 80, 120 mm) and fence porosity (ε = 22.6, 41.6, and 56.5%). These tests were conducted in an indoor subsonic, blowing-sand wind tunnel equipped with a moveable sediment bed (d50 ∼ 212 µm). The experimental mean wind velocities were u1 = 6.1 m/s, u2 = 7.4 m/s, and u3 = 9.3 m/s. We used a hot-wire anemometer to measure the flow fields, a vertical mesh sand trap to determine the sediment fluxes, and a 2D laser scanner to record the sediment accretion around the sand-trapping fences over time. The study results provide substantial theoretical and practical support for the installation and configuration of trapping fences and improving their design. The fence porosity, for example, should be chosen depending on the installation purpose. While denser fence porosities (ε1 = 22.6% and ε2 = 41.6%) can be used for initiating and facilitating the dune toe growth, fences with higher porosity (ε3 = 56.5%) are more suitable to favor the sediment accretion between foredunes and white dunes as they allow further dune growth downwind.

Детский погребальный обряд казахов Юга Западной Сибири

The article considers for the first time the children's funeral rite of the Kazakh population in the south of Western Siberia. The study covers the period from the second half of the 20th century to the present. The materials obtained in the course of expeditionary work in the Omsk, Novosibirsk and Tyumen regions were used. A description of all stages of the funeral is given - from the death of a child to the commemoration and decoration of the grave. An analysis of children's graves, identified during expeditionary research of Kazakh cemeteries in the Omsk region, is carried out. The special role in the children's funeral rite of the age and circumstances of the child's death is considered. The transition to the adult burial variant is defined as variable. The onset of physiological maturity served as a milestone. Based on the studied sources, it is concluded that the children's funeral rite among the Kazakhs as a whole is a reflection of an adult, however, it has its own well-defined features. Three main sources of their formation are singled out: the traditions of Islam, pre-Islamic ideas and innovations. The Muslim tradition regulates in detail the treatment of the soul and body of a child, depending on his age and circumstances of death. The clearest gradation exists for newborns. The Muslim rite of burial with zhanaza is performed only for newborns born alive. The stillborn, according to Islamic norms, are given a name, washed, wrapped in a shroud, but they do not read the zhanaza. An unformed fruit is simply wrapped in cloth and buried in the ground. Pre-Islamic features can be traced back in the 20th century. in leaving cradles and cribs on children's graves. A peculiar return to pre-Islamic ideas at the beginning of the 21st century is noted. in the form of a tradition to leave toys at children's graves. A new trend was the installation of fences and memorial plaques with an epitaph on the graves of babies.

Preliminary Experimental Trial of Effects of Lattice Fence Installation on Honey Bee Flight Height as Implications for Urban Beekeeping Regulations

Urban beekeeping has gained salience because of its significance in biodiversity conservation and community building. Despite this, beekeeping practices in urban areas have received negative perceptions from residents, which stem from public safety concerns. There is, therefore, a need to enhance and/or work on appropriate rules for maximizing the profits while minimizing the risks. Amongst the present regulations, the installation of barriers and setbacks is the most common rule for public safety. However, only a limited number of empirical studies have reported on their effective location and height. Thus, in this study, an experimental apiary was set up with different types of barriers installed with varying distances to observe and measure flyway patterns of honey bees. We used a 3D laser scanner, which obtained 8529 points of highly accurate flight location data in about five hours. Results showed that the heights (1.8 and 0.9 m) of the barriers installed were effective in increasing the flight altitudes. The distance of the fence, which was installed as close as 1 m from the hives, was effective as well. These findings, which showed that barriers and setbacks are effective, can have regulatory implications in designing apiaries in urban spaces, where location is often restricted.

Preventive effect of on-farm biosecurity practices against highly pathogenic avian influenza (HPAI) H5N6 infection on commercial layer farms in the Republic of Korea during the 2016-17 epidemic: A case-control study

Highly pathogenic avian influenza virus (HPAIv) H5N6 has destructive consequences on the global poultry production system. Recently, a growing number of layer farms have been heavily damaged from the HPAIv epidemic due to the increased virulence of the virus and the intensification of the production system. Therefore, stakeholders should implement effective preventive practices at the farm level that are aligned with contingency measures at the national level to minimize poultry losses. However, numerous biosecurity protocols for layer farm workers to follow have been developed, impeding efficient prevention and control. Furthermore, the effectiveness of biosecurity practices varies with the geographical condition and inter-farm contact structures. Hence, the objective of our study was to examine the preventive effect of five biosecurity actions commonly practiced at layer farms in the Republic of Korea against HPAIv H5N6: (i) fence installation around a farm, ii) rodent control inside a farm; iii) disinfection booth for visitors for disinfection protocols, iv) an anterior room in the sheds before entering the bird area and v) boots changes when moving between sheds in the same farm. We conducted a case-control study on 114 layer case farms and 129 layer control farms during the 2016-17 HPAI epidemic. The odds ratios for five on-farm biosecurity practices implemented in those study groups were estimated as a preventive effect on the HPAI infection with covariates, including seven geographical conditions and three network metrics using Bayesian hierarchical logistic regression and geographical location weighted logistic regression. The results showed that the use of a disinfection booth for personnel reduced the odds of HPAIv H5N6 infection (adjusted odds ratio [AOR] = 0.002, 95 % credible interval [CrI] = 0.00007 - 0.025) with relatively small spatial variation (minimum AOR – maximum AOR: 0.084−0.263). Changing boots between sheds on the same farm reduced the odds of HPAIv H5N6 infection (AOR = 0.160, 95 % CrI = 0.024−0.852) with relatively wide spatial variation (minimum AOR – maximum AOR = 0.270−0.688). Therefore, enhanced personnel biosecurity protocols at the farm of entry for layer farms is recommended to effectively prevent and respond to HPAIv H5N6 infection under different local condition. Our study provides an important message for layer farmers to effectively implement on-farm biosecurity actions against HPAIv H5N6 infection at their farms by setting priorities based on their spatial condition and network position.

Can virtual fences reduce wombat road mortalities?

Roadkill is a worldwide issue that can cause local population extinctions. In Australia numerous species are affected, however the bare-nosed wombat (Vombatus ursinus) is particularly vulnerable due to its preference for disturbed habitats. Collisions with motor vehicles causes significant damage to the vehicle and sometimes the driver, as well as wounding or killing the wombat. Virtual fences are light and sound-based devices, originally developed in Austria that can be used to reduce roadkill through mitigation. They have had mixed results. In this study a virtual fence was installed along a 1.5 km stretch of road in semi-rural NSW, Australia, with the aim of reducing wombat roadkill through the use of this form of mitigation strategy. The number of roadkilled wombats was counted before and after the fence was installed in March 2020. Prior to the fence being installed 23 wombats were killed and after the fence was installed six wombats were killed. Along Old Bega Road, outside of the fenced area 64 wombats were killed pre-fence installation and 17 post fence installation. Bare-nosed wombats are semi-fossorial ecosystem engineers with an important role in the ecosystem and despite being listed as Least Concern are readily impacted by roadkill. Virtual fencing implemented in regions that have high wombat roadkill rates may aid in reducing road deaths and species conservation. However, we recommend that more research is required to assess virtual fencing, as a roadkill mitigation strategy, including an investigation into a larger number of species in a range of different habitats.

Virtual fencing as a wildlife-vehicle collision mitigation measure: technical function, wildlife response and considerations for installation in an urban environment

ABSTRACT Virtual wildlife fencing presents as a cost-effective measure for roadkill mitigation, which aids in reducing fragmentation of wildlife populations by facilitating safer movement of wildlife across the landscape. In this study, we conducted an audit of a virtual fence installation in south-east Queensland, Australia. We assessed its reliability in flows of traffic and the effect that installation parameters and site conditions had on its effective operation in an urban setting. We made observations on the behavioural response of Eastern Grey Kangaroos Macropus giganteus to the acoustic signals produced by the fence. We found that the fencing activated consistently in response to headlights at dusk and dawn, and when traffic flows were dense, despite considerable variations in the range of installation parameters. However, we identified that the response of the virtual fence to headlights was affected by road curvature and we identified inconsistencies in the timing and pattern of activation in response to traffic. Behavioural observations showed a significant increase in kangaroo vigilance in response to the acoustic signal of the fence when resting or grazing, and kangaroos detected the acoustic signal up to 50 m away. While virtual fencing operates effectively and is a low-cost roadkill mitigation option that can be applied to the urban environment, more research is needed to better understand the effect of its acoustic and visual signals on wildlife behaviour and efficacy in busy urban environments.

Evaluating the construction and effectiveness of slash walls at the perimeter of regeneration harvests to exclude deer

Deer impacts on forest vegetation have complicated attempts at forest regeneration in many parts of the Northeast, Mid-Atlantic States, and other regions. Deer overabundance limits the success of forest regeneration. One strategy is to reduce deer browsing by temporarily excluding them from regeneration harvests. Because of the costs of fence installation, maintenance, and removal, we developed and tested the feasibility and effectiveness of slash walls. In 2017, 4 regeneration harvests ranging from 4.5 to 30 ha were cut. Slash and trees of marginal value proximate to the perimeter were piled into a slash wall that averaged 3.7 m to the tallest branch and 7.2 m wide. Slash walls occupied from 0.5 to 1.5 ha of the harvest area and used approximately 28,000 kg of slash and low-grade logs per 30 m section. The rate of construction depended on topography along with access to slash and low-grade trees. Construction rates for slash walls varied from 32 m/hr to 77 m/hr. The average cost of construction was $4.82/m ($1.47/ft) based on machine and operator costs of $200 (US)/hr for a weighted average cost of $541/ha ($219/ac). Fence installation can cost 3–4 times as much as slash wall construction, plus additional costs for maintenance and removal. The cost to monitor and maintain slash walls was negligible. Slash wall heights slumped approximately 8–14% per year, which reduced slash wall height by 37 cm per year. Four years after creating the slash walls, the heights of tagged seedlings of palatable species remained significantly greater inside the slash wall where deer were excluded than in adjacent control areas that were accessible to deer. We recommend slash walls minimally be constructed 3.1 m tall to the highest 5-cm-diameter branch, 7 m wide at the base, and sufficiently dense to prevent deer from being able to crawl through. This study is the first documentation of slash walls as a feasible and effective technique during regeneration harvesting to exclude deer from impacting forest vegetation. Subsequent to this study, multiple logging crews have created additional slash walls in CT, MA, NH, NY, and RI as part of commercial harvests.