Comparison of environmental, biological and anthropogenic causes of wildlife–vehicle collisions among three large herbivore species

Animal-vehicle collisions during the COVID-19 lockdown in early 2020 in the Krakow metropolitan region, Poland

The interrelations between human activity and animal populations are of increasing interest due to the emergence of the novel COVID-19 and the consequent pandemic across the world. Anthropogenic impacts of the pandemic on animals in urban-suburban environments are largely unknown. In this study, the temporal and spatial patterns of urban animal response to the COVID-19 lockdown were assessed using animal-vehicle collisions (AVC) data. We collected AVC data over two 6-month periods in 2019 and 2020 (January to June) from the largest metropolis in southern Poland, which included lockdown months. Furthermore, we used traffic data to understand the impact of lockdown on AVC in the urban area. Our analysis of 1063 AVC incidents revealed that COVID-19 related lockdown decreased AVC rates in suburban areas. However, in the urban area, even though traffic volume had significantly reduced, AVC did not decrease significantly, suggesting that lockdown did not influence the collision rates in the urban area. Our results suggest that there is a need to focus on understanding the effects of changes in traffic volume on both human behaviour and wildlife space use on the resulting impacts on AVC in the urban area.

Analysis of Water Deer Roadkills Using Point Process Modeling in Chungcheongnamdo, South Korea

The expansion of road networks and increased traffic loads have resulted in an increase in the problem of wildlife roadkill, which has a serious impact on both human safety and the wildlife population. However, roadkill data are collected primarily from the incidental sighting, thus they often lack the true-absence information. This study aims to identify the factors associated with Korean water deer (Hydropotes inermis) roadkill in Korea using the point processing modeling (PPM) approach. Water deer roadkill point data were fitted with explanatory variables derived from forest cover type, topography, and human demography maps and an animal distribution survey. Water deer roadkill showed positive associations with road density, human population density, road width, and water deer detection point density. Slope and elevation showed negative associations with roadkill. The traffic volume and adjacent water deer population may be the major driving factors in roadkill events. The results also imply that the PPM can be a flexible tool for developing roadkill mitigation strategy, providing analytical advantages of roadkill data, such as clarification of model specification and interpretation, while avoiding issues derived from a lack of true-absence information.

Quantifying Landscape Degradation Following Construction of a Highway Using Landscape Metrics in Southern Iran

Rapid expansion of roads is among the strongest drivers of the loss and degradation of natural habitats. The goal of the present study is to quantify landscape fragmentation and degradation before and after the construction of the Isfahan-Shiraz highway in southern Iran. To this end, the ecological impacts of the highway on forests, rangelands, and protected areas were evaluated. Impacts of the construction of the highway were studied within a 1,000-m buffer around the road, which was then overlaid on maps of forests, rangelands, and protected areas. Class area, number of patches, largest patch index, edge density, landscape shape index, mean patch size, and patch cohesion index were used to gauge changes in the spatial configuration of the landscape; the ecological impacts of the highway were quantified using effective mesh size (MESH), division index, and splitting index. The results indicated that after the construction of the highway, 6,406.9 ha of forest habitat, 16,647.1 ha of rangeland habitat, and 912 of the Tang-e Bostanak Protected Area will be lost. The effective MESH metric showed that after the construction of the highway, the area of forest, rangeland habitats and protected area will decrease by 20,537, 49,149, and 71,822 ha, respectively. Our findings revealed drastic habitat loss and landscape fragmentation associated with construction of the highway, serving as references for conservation planning and development.

On this side of the fence: Functional responses to linear landscape features shape the home range of large herbivores

Understanding the consequences of global change for animal movement is a major issue for conservation and management. In particular, habitat fragmentation generates increased densities of linear landscape features that can impede movements. While the influence of these features on animal movements has been intensively investigated, they may also play a key role at broader spatial scales (e.g. the home range scale) as resources, cover from predators/humans, corridors/barriers, or landmarks. How space use respond to varying densities of linear features has been mostly overlooked in large herbivores, in contrast to studies done on predators. Focusing on large herbivores should provide additional insights to understand how animals solve the trade-off between energy acquisition and mortality risk. Here, we investigated the role of anthropogenic (roads and tracks) and natural (ridges, valley bottoms and forest edges) linear features on home range features in five large herbivores. We analysed an extensive GPS monitoring data base of 710 individuals across nine populations, ranging from mountain areas mostly divided by natural features to lowlands that were highly fragmented by anthropogenic features. Nearly all of the linear features studied were found at the home range periphery, suggesting that large herbivores primarily use them as landmarks to delimit their home range. In contrast, for mountain species, ridges often occurred in the core range, probably related to their functional role in terms of resources and refuge. When the density of linear features was high, they no longer occurred predominantly at the home range periphery, but instead were found across much of the home range. We suggest that, in highly fragmented landscapes, large herbivores are constrained by the costs of memorising the spatial location of key features, and by the requirement for a minimum area to satisfy their vital needs. These patterns were mostly consistent in both males and females and across species, suggesting that linear features have a preponderant influence on how large herbivores perceive and use the landscape.

Understanding spatio-temporal patterns of deer-vehicle collisions to improve roadkill mitigation

Vehicles collide with hundreds of thousands of deer on European roads each year. This leads to animal deaths and suffering, economic damage and risks for human safety, making the reduction of road mortality a major field in conservation biology. In order to successfully reduce roadkill, we need improved knowledge regarding spatio-temporal patterns of deer-vehicle collisions (DVCs) on a landscape scale. Here, we analyzed >85,000 DVCs collected over 17 years in Denmark to investigate changes in the number of DVCs over time and to find spatio-temporal patterns of DVC occurrence. We used a use-availability design - originally developed for habitat selection analyses - to compare DVCs involving roe deer (Capreolus capreolus), red deer (Cervus elaphus) and fallow deer (Dama dama) with random road locations on a landscape scale. This approach enabled us to combine temporal (seasonal and diel variation), spatial (land cover, road density and type) and other relevant variables (deer population density, traffic, and deer activity) within the same analysis. We found that factors related to infrastructure and land cover were most important in explaining patterns of DVCs, but seasonal and diel changes, deer activity, and population density were also important in predicting the occurrence of DVCs. Importantly, patterns of DVCs were largely similar between the three deer species, with more DVCs occurring at intermediate traffic density, increasing forest cover, during dusk and dawn, and with increasing deer activity and population density. The strong and consistent patterns found here will allow the development of flexible mitigation measures. We propose that our findings could be used to develop a spatio-temporally flexible warning system for smartphones and navigation systems that is based on existing map providers, making it a widely available and cheap mitigation measure.

Strength of correlation between wildlife collision data and hunting bags varies among ungulate species and with management scale

Most European ungulate species are increasing in numbers and expanding their range. For the management and monitoring of these species, 64% of European countries rely on indirect proxies of abundance (e.g., hunting bag statistics). With increasing ungulate numbers, data on ungulate-vehicle collisions (UVC) may provide an important and inexpensive, complementary data source. Currently, it is unclear how bag statistics compare with UVC. A direct comparison of these two indices is important because both are used in ungulate management. We evaluated the relationship between UVC and ungulate hunting bags across bioclimatic, regional, and local scales, using five time lags (t−3 to t+1) for the five most common wild ungulate species in Sweden. For all species, hunting bags and UVC correlated positively, but correlation strength and time lags varied across scales and among species. The two indices correlated most strongly at the local management scale. Correlation between both indices was strong for the smaller deer species and wild boar, in particular, but much weaker for moose where we found the best fit using a 2-year time lag. For the other species, indices from the same year correlated best. We argue that the reason for moose data behaving differently is that, in Sweden, moose are formally managed using a 3-year time plan, while the other species are not. Accordingly, moose hunting bags are influenced more strongly by density-independent processes than bags of the other species. Consequently, the mismatch between the two indices may generate conflicting conclusions for management depending on the method applied.

Human-Wildlife Conflicts in Krakow City, Southern Poland

Simple Summary

Human conflicts with wildlife (HWC) are gradually increasing in urban areas with changing patterns of land-use and fragmentation. We investigated the occurrence of human-wildlife conflicts in Krakow city, southern Poland, based on recorded conflict incidents with wild animals in three categories, i.e., animal-vehicle collisions, intrusion to property, and damages. The three most common conflict species were red fox, roe deer and wild boar. We analysed the spatial and temporal distribution of the HWC. The results of the study can be used to identify locations of potential HWC hot spots in the city and provide information for mitigation actions.

Abstract

Efforts to reduce human-wildlife-conflict are integral to wildlife management and conservation in urban habitats. In our study, we identified the HWC situations in urban areas of Krakow city, based on animal-vehicle collisions, intrusion to property, and damages. Hot spot analysis and Moran’s Index were used to identify the location of maximum potential conflict. We analysed 2512 incidents in which animals (of which 85% included mammals and 15% birds) were involved in conflict situations between 2007 and 2013. A significant seasonal variation was observed among the animals. We also identified roe deer (50.23%), red fox (22.80%) and wild boar (11.40%), as the three prominent conflicted animals. Getis–Ord Gi* analysis was used to identify spatial clusters of conflict. A significant spatial association was found in the location of clusters of hot spots in specific land-use based on Moran’s Index. Hot spots of roe deer and wild boar were high in grasslands and in forest and for red fox in built-up area. The results underscore the notion that conservation and wildlife management efforts must take into account differences in the seasonality of HWC among species. This information can be used to inform mitigation strategies.