Wildlife accident prevention
Traffic accidents involving game have long been a risk to road safety. Contrary to the fundamental trend of declining accident numbers, the number of statistically recorded, serious wildlife accidents remains at roughly the same level. The number of accidents involving damage to property and damage caused by wildlife accidents is on the rise. In addition to the risk to road safety, wildlife accidents could threat the population of endangered species and are an expression of the barrier effect of roads.
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For the prevention of wildlife accidents, there is currently an increasing use of wildlife crossing traffic signs, wildlife fences, wildlife warning systems and wildlife warning modules (auditory, olfactory, visual). However, there is only limited evidence on the effectiveness of these and other measures.
In June 2017, a full-day expert workshop was held at the BASt on the concepts and effects of measures to prevent wildlife accidents. The main topic was the presentation of the results of a first research project on the analysis of the effects of different optical wildlife warning modules.
Together with BASt experts from the fields of environmental protection, road traffic technology, traffic psychology, road operation, vehicle safety and automated driving, more than 40 experts from Germany and Austria exchanged their experiences with regard to international wildlife accident research.
The constant risk for road safety and the hitherto incomplete state of knowledge on the conception and effect of measures for wildlife accident prevention justify a complex and consolidated series of studies on the causes of wildlife accidents and measures for prevention.
The BASt focuses on the following topics in this area:
Identification of traffic safety deficits and provision of a data source for further analyses
In the federal accident statistics, wildlife accidents are recorded along with serious personal injury or fatalities. The vast majority of traffic accidents involving game are "minor accidents" which are not recorded by the police in every federal state. For example, it is often not known on which road sections there are frequent wildlife accident sites. A uniform standard and data transparency in the recording of wildlife accidents are required for the effective control of wildlife accident prevention measures. An inventory of the accident recording modalities and a supplementation and, if necessary, upgrading of other data sources, such as animal find registers and game reports, can considerably improve the database on wild game accidents and form the basis for further analyses.
Analyses with Geographical Information Systems (GIS)
Wildlife accident prevention measures are intended to defuse accident black spots. For this reason, it is first necessary to evaluate the number of wildlife accidents on federal highways in all federal states and to determine the focal points of wildlife accidents. The accident black spots are to be processed in a GIS analysis in such a way that ecological causes for accident accumulations can be identified and scientifically substantiated indications for suitable prevention measures can be given on road sections with increased wildlife accident potential.
Influencing the game to avoid conflicts
Little is known about the behaviour of wild animals on roads in Germany. A study on the perception of the road and road traffic by deer using GPS-supported spatial observation confirms a large variance in the behaviour of animals in road space. Deer that have integrated roads into their habitat and have adapted to road space and traffic rarely avoid roads even during the day.
Possibilities of influencing (smell, noise, etc.)
In order to keep the wild animals away from the road, various methods have been developed. In particular, scent barriers, reflectors as well as acoustic wildlife warning and combination products are attached to roads by hunters and some road construction authorities. Statements about the effectiveness of the measures could not be reliably derived so far, because either the investigation framework or the applied methods were not used scientifically flawlessly. Research and surveys are currently being carried out by various institutions in which statistical evaluations of changes in accident frequencies are to be used to determine the influence of scent barriers and wildlife warnings on game.
Mode of action Wildlife warning reflectors
The light-technical operating principle of optical wildlife warning devices has already been investigated. Overall, the results led to the conclusion that wildlife warning reflectors cannot generate sufficient optical stimuli for wild animals that could reliably induce a change in the behaviour of the animals. However, it cannot be ruled out that retroreflective wildlife warning reflectors represent an indication stimulus for drivers (see Human Factor).
Influencing road users in the event of impending conflicts with wildlife
There is evidence that, in some cases, the number of accidents on routes equipped with reflectors will fall at least temporarily. Since wildlife warning reflectors are not expected to have a reliable influence on wildlife, the question arises whether and to what extent wildlife warning reflectors have an effect on the behaviour of road users. A survey on the knowledge of wildlife warning reflectors suggests that road users are aware of wildlife warning reflectors and their intended use and may change their driving behaviour on appropriately equipped routes. The effect and limits of the use of static indications of possible conflicts with wildlife to locally influence road users shall be investigated.
Effect of wildlife warning systems
The use of wildlife warning systems requires the existence of a multi-lane, flat road with game protection fencing on both sides. The functionality of electronic wildlife warning systems on federal highways is based on a permeable area about 50 metres wide within a wildlife fence several kilometres long, through which wild animals can cross a federal highway. If animals are detected within the detection field in the permeable area, this is indicated on variable traffic signs together with a speed limit. In order to increase the reliability and effectiveness of a wild animal warning system, further investigations must be carried out.
Effects of automated driving
Automated driver assistance systems contribute to road safety by compensating driving errors and relieving the strain on the driver. The transmission of relevant information by vehicle sensors and infrastructurally installed sensors enables animal crossings at wildlife warning systems to be displayed directly in the vehicle. Sensors in the vehicle can also react to obstacles in the road side area.
Infrastructure factor (agricultural/roads)
Avoidance of conflict situations Wildlife / traffic
In order to avoid accidents, wildlife fences are used in particular on highly frequented federal highways. In application of the Wildlife Protection Fence Directive (WSchZR, 1985), for example, considerable funds are being invested in protection systems to increase traffic safety. However, it is not yet known which protection systems are how efficient, thus how biologically effective and economically suitable for large-scale use.
Further investigations are necessary to improve the efficiency of wildlife fences and to further develop the underlying regulations and adapt them to newer requirements.
The food supply for wildlife has changed in recent decades as a result of changes in agricultural structures, emissions and climate change. Animal populations relevant for the planning of wildlife fences have often increased. The separating effect of roads between resting and food habitats simultaneously leads to conflicts. For this reason, it is necessary to investigate the influence of agricultural use or the use of compensation areas on roads with a focus on wildlife accidents on the frequency of wildlife accidents and how this can be quantified.
Habitats / Networking
Wildlife habitats in Germany are fragmented by the dense traffic network and the increasing volume of traffic. These land losses reduce and isolate animal habitats. The high volume of traffic leads to animal losses, which can threaten the population of endangered species. Disturbances caused by people's leisure behaviour also lead to changes in the use of habitats. By networking these areas by means of green bridges and the establishment of rest zones, fragmented areas can be connected and the number of wildlife accidents reduced.