In all western states, domestic animal and wildlife populations are increasing as well as the vehicular traffic volumes. Consequently, increases in animal-vehicle collisions have been reported by many states. The purpose of this report is to provide a synthesis of animal-vehicle collision mitigation measures utilized by other states and to provide a cost-effective recommendation for ADOT to further reduce animal-vehicle collisions. Preparation for this report included assembling documented studies currently underway and existing reports, and conducting a survey among selected states and countries to learn what practices have been used for solving or alleviating animal-vehicle collisions.

NCHRP synthesis 370 examines the extent to which data from animal-vehicle collision accident reports and animal carcass counts are collected, analyzed, and used throughout the United States and Canada.

This report reviews 39 mitigation measures that reduce animal vehicle collisions and that provide habitat connectivity for wildlife across highways. The overview is restricted to mitigation measures aimed at large terrestrial mammals (deer size and larger). However, this report also includes information regarding how such measures may affect or benefit federally endangered or threatened species in Montana, regardless of their size. In addition to the detailed information for each mitigation measure, a summary table is provided that provides at a glance information on the costs and benefits of the individual mitigation measures for which such data were available. Furthermore, the report graphically illustrates which measures have the best monetary balance (the difference between benefits and costs) and which measures reduce animal vehicle collisions and associated costs best. Based on the results, the authors of this report identified wildlife fencing, with or without wildlife underpasses or a combination of wildlife underpasses and overpasses, and animal detection systems with wildlife fencing, as the most cost effective mitigation measures. Animal detection systems without wildlife fences or wildlife fences with a high density of wildlife overpasses are also cost effective, but more data on system effectiveness are needed before these systems are recommended for implementation rather than further study. The final section of the report provides suggestions on the implementation or study for each of the 39 mitigation measures.

TRB¿s National Cooperative Highway Research Program (NCHRP) Report 615: Evaluation of the Use and Effectiveness of Wildlife Crossings explores development of an interactive, web-based decision guide protocol for the selection, configuration, and location of wildlife crossings.

The US 93 reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife sensitive highway design efforts to occur in the continental United States. The reconstruction will include installations of 42 fish and wildlife crossing structures and approximately 15 mi (24 km) of wildlife exclusion fencing for a total investment of over 9 million dollars. This report documents the success of using a context sensitive approach to collaboratively redesign a rural highway within a multiple use landscape that accommodates the needs and concerns of different institutions, cultures and priorities. Further, this report introduces baseline field data collection methods and results that are being used to evaluate how the wildlife crossing structures and wildlife fencing affect deer and bear vehicle collisions and movements in a multiple use rural landscape. The preconstruction data summarized here, and in combination with complementary post construction data, will address the following goals of the evaluation study: (1) determine what effect US 93 wildlife crossing structures and fencing have on the frequency of animal vehicle collisions and successful animal highway crossings; (2) document the design decision making processes and lessons learned as a case study; and (3) identify best management practices and further research. These issues are addressed via a literature review of important considerations related to locating, designing, and evaluating the effectiveness of wildlife crossings and exclusion fencing; a case study and project history; summary and synthesis of field data collection efforts; overview of other relevant and repeatable field studies; and a discussion about the measures of effectiveness and post-construction data collection recommendations. The ultimate value of the information in this report will be realized when the reconstruction is complete and post construction field data is collected to comparatively assess the effect of the wildlife mitigation on the parameters of interest identified in the goals. Perhaps one of the most important insights gained from the preconstruction research is that, due to the myriad sources of unquantifiable variation in the environment, many years of monitoring are necessary to make valid inferences. Given the paucity of long term, before after field studies assessing the effects of wildlife exclusion fencing and crossing structures on wildlife and driver safety, the US 93 wildlife mitigation evaluation, when completed, will provide useful results, lessons learned, and best management practices to guide other wildlife mitigation efforts in the future.

Animal-vehicle collisions (AVCs) have a growing impact in the United States in terms of safety, economic loss, and species conservation. According to estimates from insurance claims, Virginia has consistently ranked as one of the top seven states for deer-vehicle collisions (DVCs) since 2002. Of the state's estimated 43,500 to 47,700 DVCs in 2006, less than 14% were reported to the police and stored in the Virginia Department of Transportation's (VDOT) accident database. Virginia has no standardized method of sufficiently tracking AVC occurrences and locations, creating difficulty in researching and implementing mitigation efforts to reduce accidents. Valuable AVC data can be obtained from documenting the instances and locations of animal carcasses from the roadway, but most transportation organizations do not systematically record these removals. This project entailed testing a personal data assistant (PDA) enabled with a global positioning system (GPS) receiver for the collection and analyses of animal carcass removals (CRs) from the roadway. Using GPS-enabled PDAs and software developed by Western Transportation Institute, maintenance personnel from a VDOT area headquarters in Rockbridge County collected 8 months of spatially accurate CR data. Rockbridge County DVC estimates derived from the CR data collected for this study were more than 9 times greater than the number of AVCs reported in police records. These spatial data can be easily used for density analyses to determine "hotspots" of AVCs. Implementing mitigation at these areas can ultimately lead to fewer AVCs and associated reductions of human deaths, injuries, and financial losses; improved traffic operations; a reduction in maintenance costs related to carcass removal and disposal; and wildlife conservation. VDOT is currently undergoing changes to its method of documenting roadway maintenance activities, including the deployment of GPS-enabled PDAs to all area headquarters. These PDAs provide a mechanism for collecting spatially accurate and standardized CR data, but collecting and reporting CRs are currently not requirements. Given the PDA's ease of use and the benefits these data would provide, the study recommends that this procedure be integrated into regular practice by VDOT area headquarters. As VDOT is receiving added regulatory pressure to implement measures to reduce AVCs, improving CR data collection using the technology described in this report can help provide an objective method for deciding whether and where mitigation is needed.