Mitigating Bighorn Sheep–Vehicle Collisions and Habitat Fragmentation with Overpasses and Adaptive Mitigation

As transportation infrastructure expands to accommodate increasing human population growth, wildlife–vehicle conflicts (WVCs) are a growing concern for motorist safety and wildlife populations. In the case of large ungulates, minimal information exists on successful mitigation of WVCs involving bighorn sheep (Ovis canadensis) and habitat fragmentation. Too address this void, we evaluated the effectiveness of 3 new wildlife overpasses, 3 culverts, 2 bridges, and ungulate exclusionary fencing as potential desert bighorn sheep (O. c. nelsoni; sheep) crossing opportunities along US Highway 93 in Arizona, USA. We evaluated sheep movements using global positioning system (GPS) radio-transmitter collars and remote cameras for 4 years from March 2011 to March 2015 and sheep–vehicle collision data collected from 2011 to 2020. Although GPS determined pre- and post-mitigation passage rates of sheep that crossed US Highway 93 were initially similar, they increased every year and were on average 217% higher following inclusion of wildlife crossings and by year 4 had ultimately increased 633% from pre-construction rates. Cameras recorded 6,936 crossings by a dozen wildlife species with sheep accounting for 95% of all crossings. Sheep used the 3 overpasses (90% of all sheep crossings) disproportionately more than the 3 culverts and 2 underpasses (10% of all sheep crossings) in the same area, and use of the 3 overpasses increased 905% in the first year. Sheep initially used the 30-m-wide overpasses at 83% and 175% higher passage rates than 2 15-m-wide structures; however, by year 4 passage rates were similar across overpasses. From February 2011 through February 2020, we documented 0.8 sheep–vehicle collisions/year for an overall 93.3% reduction from the 12 collisions per year previously documented. Most of the collisions occurred immediately following completion of the project and gradually reduced as sheep access points were identified and addressed through an adaptive mitigation process to iteratively improve success. Overpasses appear to be the preferred wildlife crossing type for sheep and when properly located and linked with ungulate exclusion fencing successfully reduced collisions and habitat fragmentation. These findings add to our knowledge base of effective roadway mitigation for different species. Long-term monitoring informs species learning curves, preference of wildlife crossing structure type, and adaptive mitigation opportunities to increase effectiveness of mitigation measures on current and future projects

Research priorities to fill knowledge gaps in wild boar management measures that could improve the control of African swine fever in wild boar populations

The European Commission asked EFSA to provide study designs for the investigation of four research domains (RDs) according to major gaps in knowledge identified by EFSA in a report published in 2019: (RD 1) African swine fever (ASF) epidemiology in wild boar; (RD 2) ASF transmission by vectors; (RD 3) African swine fever virus (ASFV) survival in the environment, and (RD 4) the patterns of seasonality of ASF in wild boar and domestic pigs in the EU. In this Scientific Opinion, the second RD on ASF epidemiology in wild boar is addressed. Twenty-nine research objectives were proposed by the working group and broader ASF expert networks and 23 of these research objectives met a prespecified inclusion criterion. Fourteen of these 23 research objectives met the predefined threshold for selection and so were prioritised based on the following set of criteria: (1) the impact on ASF management; (2) the feasibility or practicality to carry out the study; (3) the potential implementation of study results in practice; (4) a possible short time-frame study (< 1 year); (5) the novelty of the study; and (6) if it was a priority for risk managers. Finally, after further elimination of three of the proposed research objectives due to overlapping scope of studies published during the development of this opinion, 11 research priorities were elaborated into short research proposals, considering the potential impact on ASF management and the period of one year for the research activities.info:eu-repo/semantics/publishedVersio

Localism\u27s Ecology: Protecting and Restoring Habitat in the Suburban Nation

There is wide agreement among conservation activists and scientists alike that loss and alteration of habitat are the leading threats to biodiversity in America. Suburbs and exurbs, though, are only beginning to acknowledge that they are the problem in the struggle to stem the tide of “sprawl” and other economic processes producing ecosystem-wide habitat degradation today. A recent resurgence in academic and activist attention to local governments in America is reconsidering them as viable solutions to this problem. But most of this dialogue is being based upon a mistaken conception of local governance. Much of the legal scholarship on local environmentalism has ignored the reality of our localism and its role in the creation of the ever-expanding built landscape in America. This paper argues that this lack of realism in the current debate about local environmental law renders it blind to the vices of local governments and some of their sham conservation measures, but also to their counterintuitive virtues and possibilities for real conservation progress. Local government’s deep connection to private property entrepreneurialism is what has made it so practically powerful in resisting so many state and federal environmental initiatives. But it may well be this dimension of our localism that renders it uniquely fit to the tasks of real habitat protection and restoration in the twenty-first century