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Highways can fragment habitat and be a significant mortality source for mammals. Wildlife exclusion fencing has been shown to reduce wildlife-vehicle collisions, but can also prevent animals from escaping the highway corridor if they enter at access roads or at fence ends. Earthen escape ramps, or “jumpouts,” have been proposed as a possible solution but remain relatively untested. From 2012-2014, we used wildlife cameras to continuously document wildlife use of four jumpout ramps constructed as part of a 2.5-mile wildlife exclusion fence project along Highway 101 near San Luis Obispo, California. Mule deer occasionally used the jumpouts, but quantifying the rate of utilization was confounded by repeated visits by the same individuals. Male and female deer appeared to have different responses to the jumpouts, which warrants deeper investigation using additional data collected from further monitoring through mid-2017. The longer dataset will also better document how individual deer learn to use the jumpouts. Fenced highways can also reduce connectivity unless there is sufficient use of crossing structures. We documented mountain lion, bobcat, black bear, and mule deer used culverts and underpasses in and adjacent to the wildlife fence zone from 2012-2014. Mule deer used the large underpasses almost exclusively, and rarely if ever used culverts. Bear used a wider variety of structures, and bobcats were detected at almost every site and at a higher rate than the other taxa. Mountain lion detections were quite rare, likely due to lower population density in the study area. We propose a deeper multivariate analysis of the factors influencing these species’ use of culverts including culvert dimensionality, nearby habitat, and proximity to cover, based on an expanded dataset of up to five years of continual monitoring at certain sites. The goal of these analyses is to provide information that will help reduce wildlife-vehicle collisions while facilitating regional wildlife connectivity.

As professional secretory cells, β-cells require adaptable mRNA translation to facilitate a rapid synthesis of proteins, including insulin, in response to changing metabolic cues. Specialized mRNA translation programs are essential drivers of cellular development and differentiation. However, in the pancreatic β-cell, the majority of factors identified to promote growth and development function primarily at the level of transcription. Therefore, despite its importance, the regulatory role of mRNA translation in the formation and maintenance of functional β-cells is not well defined. In this study, we have identified a translational regulatory mechanism mediated by the specialized mRNA translation factor eukaryotic initiation factor 5A (eIF5A), which facilitates the maintenance of β-cell identity and function. The mRNA translation function of eIF5A is only active when it is posttranslationally modified (“hypusinated”) by the enzyme deoxyhypusine synthase (DHPS). We have discovered that the absence of β-cell DHPS in mice reduces the synthesis of proteins critical to β-cell identity and function at the stage of β-cell maturation, leading to a rapid and reproducible onset of diabetes. Therefore, our work has revealed a gatekeeper of specialized mRNA translation that permits the β-cell, a metabolically responsive secretory cell, to maintain the integrity of protein synthesis necessary during times of induced or increased demand. [ABSTRACT FROM AUTHOR]

This pair of papers examines and describes the state action necessary to make markets function as environmental policy instruments and as strategies of governance. They do this through a detailed look at the mechanics of environmental credit compliance markets in the US states of Oregon, Ohio, and North Carolina in which stream credits are privately created and sold to developers who have impacted protected stream systems. In this paper, we examine the tools, techniques, and people involved in the creation of a value-bearing stream credit out of a physical stream or river site. These observations reveal important principles of how science functions within governance, as well as where gaps and resistances appear that create unforeseen outcomes in market-led policy. We examine the construction and use of instruments that define natural processes as objects with value; these techniques and tools include databases and spreadsheets, algorithms, and field scoring tools that have been scavenged from a wide range of scientific and governance practices and are not themselves inherently capitalist or developed for capitalist purposes. In three different state settings, the move from measure to value is made in different ways that depend on the local institutional and social context. However, they all act to render a network of interacting ecological forces as a field of discrete ecosystem objects amenable to governance with markets. [ABSTRACT FROM AUTHOR]

This pair of papers examines and describes the state action necessary to make markets function as environmental policy instruments and as strategies of governance. We do this through a detailed look at the mechanics of environmental credit compliance markets in the US states of Oregon, Ohio, and North Carolina in which stream credits are privately created and sold to developers who have impacted protected stream systems. In this paper, we observe that the governance of streams as water resources requires the state to create a scalar hierarchy that fixes certain characteristics of streams at certain scales of state action. These fixes attempt to resolve, bracket, or ignore the temporal and spatial variability of streams that can confound governance; however, these variabilities are essential to the scientific study of streams. At each of the four distinct scales, four different operations crucial to market function were observed; at each scale, elements of natural variability were fixed or confined to be expressed only within the given scale. These observations reveal principles of how scale functions within environmental governance, as well as failures where gaps and resistances appear that create unforeseen outcomes in market-led policy. In three different state settings, the establishment of a fixed scale of governance is made in different ways that depend on the local institutional and social context. However, they all act to render an unruly set of temporal and spatial flows as instead occurring within certain fixed scalar boundaries, and thus amenable to governance with markets. [ABSTRACT FROM AUTHOR]

Context: A central problem in road ecology is the need to minimise roadkill without exacerbating fragmentation. The best current solution to this problem is wildlife-exclusion fencing combined with crossing structures. However, because species vary in their propensity to use crossing structures, optimising their design for a suite of species remains a challenge. Aims: We investigated medium- and large-mammal use of undercrossings along Highway 101 in the Central Coast of California. Specifically, we quantified how undercrossing size, surrounding habitat, and the presence of a wildlife-exclusion fence, influenced overall species richness, as well as use by black bear, mule deer, puma, and bobcat. Methods: Using wildlife cameras, we documented mammal use at 11 undercrossings in our study area. We calculated the openness index of each undercrossing and remotely measured habitat features, such as percentage tree cover, and distance to nearest stream. We determined the relative importance of these factors on overall species richness, and the activity of focal species, using generalised linear mixed models in an information-theoretic framework. Key results: Mesocarnivores used a wider variety of undercrossings, and used them more frequently, than did larger mammals. Species richness and bear activity were greater closer to streams, and there was more bear activity at undercrossings within the wildlife-exclusion fence zone than outside it. Deer activity was strongly and positively related to undercrossing openness. Our puma and bobcat analyses were uninformative, likely because we detected puma too infrequently, and because bobcats showed little variation in use across sites. Conclusions: Our results support previous research highlighting natural travel corridors (e.g. riparian areas) as important places for wildlife crossings, both for a diversity of medium–large mammals and a low-density large carnivore. Ungulates may be the most selective taxa in respect to undercrossing use. Implications: Large, open undercrossings along natural travel routes accommodate the greatest diversity of medium–large mammal species. Designing wildlife crossing structures for a suite of species remains a challenge. We monitored 11 crossings along a major highway in California from 2012 to 2017 and found that mammal species richness and black bear use were greater closer to streams, whereas mule deer almost exclusively used large undercrossings. Large undercrossings associated with natural corridors are likely to promote connectivity for the most species of medium–large mammals. Photograph by the authors. [ABSTRACT FROM AUTHOR]