Factors influencing the spatial patterns of vertebrate roadkill in South Africa: The Greater Mapungubwe Transfrontier Conservation Area as a case study

Abstract

Few studies have investigated the factors that influence roadkill occurrence in developing countries. In 2013, we monitored a 100‐km section of the road (comprising the R572 and R521 regional highways and the D2662) that pass through the Greater Mapungubwe Transfrontier Conservation Area in South Africa, to assess the possible factors influencing roadkill. Over a period of 120 days, and across the three ecological seasons, we recorded 981 roadkills (rate = 0.08 roadkill/km/day) from four vertebrate taxonomic groups. We generated predictive models of roadkill from one combined data set that considered eight variables identified from the literature as potential correlates of roadkill. The model that included the distance of the fence from the road, habitat type adjacent to the road, and the presence of a hill in the road (i.e., elevation) or a bank on the side of the road best explained roadkill occurrence. More roadkill was predicted to occur in both open and dense mopane and dense mixed bushveld habitats, on a hill, when there was a bank on the side of the road, and as the distance between the road verge and a fence decreased. Our model provides some insight into the significant predictors of roadkill occurrence and is therefore a valuable tool in identifying sites of high‐potential roadkill frequency and formulating mitigation measures for reducing road mortalities.

Wildlife roadkill in the Tsavo Ecosystem, Kenya: identifying hotspots, potential drivers, and affected species

“…In terms of numbers, small to medium-sized mammals were the most abundant roadkill (53%), followed by birds (32%), reptiles (10%), and lastly large mammals (5%). These findings contrast those from Tarangire-Manyara ecosystem and Mapungubwe Transfrontier conservation area in South Africa, where birds were the most common roadkill at 50% and mammals (large and small to medium-sized combined) came second at 27–30% ( Kioko et al., 2015 ; Collinson et al., 2019 ). The deviation in taxon composition represented in roadkill across studies may also be influenced by data collection protocols such as the timing of surveillance, and speed of the drive during monitoring.…”

“…These projects will crisscross the continent passing through remote regions and key ecosystems that sustain high levels of biodiversity. There are limited studies on the ecological impacts of roads in the African tropics (But see: Caro et al., 2014 ; Kioko et al., 2015 ; Nyirenda et al., 2017 ; Collinson et al., 2019 ), where road infrastructure development is projected to grow rapidly into pristine environments and protected areas ( Laurance et al., 2015 ; Alamgir et al., 2017 ). Most road ecology studies have focused on understanding impacts of roads on wildlife in developed countries and temperate biomes ( Dean et al., 2019 ).…”

Stay home, stay safe? High habitat suitability and environmental connectivity increases road mortality in a colonizing mesocarnivore

“…Predictive modelling approaches provide strong support in the investigation of the environmental factors affecting roadkill risk, thus enabling researchers to relate roadkill events to road-related characteristics (e.g., Malo et al 2004;Green-Barber and Old 2019;Collinson et al 2019), as well as to predict areas where roadkill risk is higher, integrating data on habitat suitability and connectivity (Girardet et al 2015;Fabrizio et al 2019a, b;Russo et al 2020). Such studies provide important information that can be used by road managers to develop adequate road designs through the implementation of mitigation measures (Malo et al 2004;Plante et al 2019).…”

Decreased traffic volume during COVID-19 did not reduce roadkill on fenced highway network in Japan

“…Studies have identified the factors that have the strongest effect on WVCs (Bencin et al 2019 ; Williams et al 2019 ). Some factors for roadkill occurrence are known; land use (Fillus et al 2020), road characteristics and fencing (Collinson et al 2019 ), ecology of species (Williams et al 2019 ) and population size (Grilio et al 2020). Traffic volume and vehicle speed are the two most important factors affecting the location and numbers of roadkill (Farmer and Brooks 2012 ; Lin 2016 ; Zhang et al 2018 ; Filius et al 2020 ).…”