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Creating and maintaining sustainable transportation systems depends in part on understanding and mitigating ecological impacts. Wildlife crossing structures (WCS) are often used to mitigate impacts on wildlife populations. WCS and existing structures may provide passage for multiple species, depending on their sensitivity to traffic disturbance and perception of the roadway. In a previous project, the research team found that traffic conditions and traffic noise could reduce WCS effectiveness in facilitating passage of diverse and sensitive species. In the current project, they expanded the geographic scope to 26 sites throughout California, including detailed measurements of vehicle noise and lighting impacts on wildlife use of structures. They investigated individual animal behavior as the animals approached structures as a possible mechanism for reducing species diversity due to traffic disturbance. In order to inform future WCS planning, placement and construction, the team studied traffic noise and light impacts on wildlife in the vicinity of the proposed Liberty Canyon wildlife over-crossing (over US 101), the first and largest of its kind in California. They improved a preliminary statistical model of the effects of traffic on WCS use of existing structures. The authors recommend strategies for transportation agencies to use in developing and modifying WCS to improve wildlife passage.View the NCST Project Webpage

This paper describes a generalizable planning and assessment process fortransportation planning adaptive to sea level rise (SLR). State Route 37(SR-37) is the California highway most vulnerable to temporary floodingand permanent inundation as a result of SLR. Like many other coastal highwaysin the United States, SR-37 is adjacent to protected coastal systems(e.g., beaches, tidal wetlands), meaning that any activity on the highway issubject to regulatory oversight. Both SR-37 and the surrounding marshesare vulnerable to the effects of SLR. Because of a combination of congestionand threats from SLR, planning for a new highway adaptive and resilientto SLR impacts was conducted in the context of stakeholder participationand Eco-Logical, a planning process developed by FHWA to better integratetransportation and environmental planning. To understand whichstretches of SR-37 might be most vulnerable to SLR and to what degree, amodel of potential inundation was developed with a recent, high-resolutionelevation assessment conducted using lidar. This model projects potentialinundation by comparing future daily and extreme tide levels with surroundingground elevations. The vulnerability of each segment was scoredaccording to its exposure to SLR effects, sensitivity to SLR, and adaptivecapacity (ability of other roadways to absorb traffic). The risk to each segmentfrom SLR was determined by estimating and aggregating impacts tocosts of improvement, recovery time (from impacts), public safety impacts,economic impacts, impacts on transit routes, proximity to communitiesof concern, and impacts on recreational activities.

Highways provide commuter traffic and goods movement among regions and cities through wild, protected areas. Wildlife-vehicle collisions (WVC) can occur frequently when wildlife are present, impacting drivers and animals. Because collisions are often avoidable with constructed mitigation and reduced speeds, transportation agencies often want to know where they can act most effectively and what kinds of mitigation are cost-effective. For this study, WVC occurrences were obtained from two sources: 1) highway agencies that monitor carcass retrieval and disposal by agency maintenance staff and 2) opportunistic observations of carcasses by participants in two statewide systems, the California Roadkill Observation System (CROS; http://wildlifecrossing.net/california) and the Maine Audubon Wildlife Road Watch (MAWRW; http://wildlifecrossing.net/maine). Between September, 2009 and December 31, 2014, >33,700 independent observations of >450 vertebrate species had been recorded in these online, form-based informatics systems by >1,300 observers. We asked whether or not WVC observations collected by these extensive, volunteer-science networks could be used to inform transportation-mitigation planning. Cluster analyses of volunteer-observed WVC were performed using spatial autocorrelation tests for parts or all of 34 state highways and interstates. Statistically-significant WVC hotspots were modeled using the Getis- Ord Gi* statistic. High density locations of WVC, that were not necessarily hotspots, were also visualized. Statistically-significant hotspots were identified along ~7,900 km of highways. These hotspots are shown to vary in position from year to year. For highways with frequent deer-vehicle collisions, annual costs fromcollisions ranged from US$0 to >US$30,000/km. Carcass clusters from volunteer data had very little or no overlap with similar findings from agency-collected WVC data, during a different time-range. We show that both state agency-collected and volunteer-collection of WVC observations could be useful in prioritizing mitigation action at US state-scales by state transportation agencies to protect biodiversity and driver safety. Because of the spatial extent and taxonomic accuracy at which volunteer observations can be collected, these may be the most important source of data for transportation agencies to protect drivers and wildlife.

Artificial light at night (ALAN) is increasing in extent and intensity across the globe. It has been shown to interfere with animal sensory systems, orientation and distribution, with the potential to cause significant ecological impacts. We analysed the locations of 102 mountain lions (Puma concolor) in a light-polluted region in California. We modelled their distribution relative to environmental and human-disturbance variables, including upward radiance (nearby lights), zenith brightness (sky glow) and natural illumination from moonlight. We found that mountain lion probability of presence was highly related to upward radiance, that is, related to lights within approximately 500 m. Despite a general pattern of avoidance of locations with high upward radiance, there were large differences in degree of avoidance among individuals. The amount of light from artificial sky glow was not influential when included together with upward radiance in the models, and illumination from moonlight was not influential at all. Our results suggest that changes in visibility associated with lunar cycles and sky glow are less important for mountain lions in their selection of light landscapes than avoiding potential interactions with humans represented by the presence of nearby lights on the ground. This article is part of the theme issue 'Light pollution in complex ecological systems'. [ABSTRACT FROM AUTHOR]

Abstract.--The eastern gray squirrel, Sciurus carolinensis (EGS) has been introduced to California and has expanded its geographic range since initial introductions. In this study we projected the potential future geographic [...]

This project included estimation of animal occurrence near and using structures (e.g., culverts, street, and RR crossing structures) to cross the Interstate-80 right-of-way in the Sierra Nevada, California. A combination of track plates near over-crossings and remote cameras at under-crossings was used to index wildlife occurrence and crossings. Diversity was relatively low in the highway right-of-way and at highway under-crossings. Across six highway under-crossings, only eight of 38 possible species were observed moving through these crossings from one side of the highway right-of-way to the other. Alpha diversity at highway crossings ranged widely for wildlife near street under and over-crossings, but was not related to nearby land development. Wildlife use of existing under-crossing structures was inversely proportional to the presence of humans and frequency of human use of the same structures. This has important implications for effectiveness of existing structures and purpose-built “wildlife crossings” to provide for wildlife movement.

The numerous effects roads have on the surrounding environment were investigated and geographically modeled. Several of these effects were then isolated and looked at in greater detail, developing a model that represents the various interactions between a road and the surrounding region. These road effects could be expressed in a GIS (geographic information system) environment, based on user-inputs. A traffic noise model was used to estimate the extent and intensity of this road effect. Environmental attributes were also summarized within the traffic noise effect zone as an example of evaluation of road effects useful during early transportation planning. The model was designed to be a proof-of-concept of a standalone tool for environmental and transportation planners in local and state agencies.

The Safe Passages project is a collaborationbetween scientists at UC Davis and nongovernmentalconservation organizations(Defenders of Wildlife, Conservation BiologyInstitute, and South Coast Wildlands), inconsultation with state agencies (CaliforniaDepartments of Transportation and Fish andGame), and is intended to encourage theinclusion of habitat connectivity planning andprotection in local and regional planning insupport of the State Wildlife Action Plan. It wasdesigned to be a model effort, with relevance toregions struggling with finding ways to conservewildlife and natural processes in the face ofdevelopment. One major ecological process atrisk is isolation of wildlife populations andreduction of the permeability of the landscapeto wildlife movement. The project draws uponcontemporary scientific understanding ofwildlife movement, physical connections onlandscapes, and land‐use and transportationplanning in order to better fit developmentpatterns to the needs of natural processes,especially wildlife movement.As its name implies, the projectaddresses the need for finding safe passage forwildlife movement through the diverse regionsof California. Two philosophical choices weremade in designing this project: 1) wildlifemovement is not limited to managed reservesand corridors, but may also occur in the nonnaturallandscape matrix, and 2) that local andregional planners can become aware of and beincluded in the process of conservingconnectivity. In the first case, the computermodeling that was done in this project wasbased on the idea that wildlife might originatetheir movement from anywhere and move inthe least‐costly direction. This results in asurface of possible wildlife movement based onhabitat preference and barriers to safe passage.In the second case, planners in the San JoaquinValley Blueprint process learned of our overallproject goals and methods and a number ofcities or counties expressed interest in workingwith us. We chose the city of Riverbank, in partbecause the community development directorshowed clear interest in using the products ofour work in the General Planning and SpecificPlanning processes.This project has evolved to includemore ideas and potential partners, including theCalifornia Department of Fish and Game (DFG),the Local Government Commission, and otheracademic researchers. This evolution hasextended our project horizon indefinitely with acombination of a DFG contract andcollaborative proposal development. Howeverthe main project goal of setting the standard forhow connectivity can be included in local andregional planning has stayed constant. Ourpartners will help us develop a sea change inthe recognition and protection of safe passagesfor wildlife movement throughout California’sSan Joaquin Valley and beyond.

Fertilin, a sperm protein of the metalloprotease/disintegrin/cysteine-rich (MDC) family, plays a critical role in sperm-egg binding in mammals. Peptides corresponding to the disintegrin domain of fertilin and antibodies against fertilin have been shown to inhibit mammalian sperm-egg binding and fusion. A protein from the same family, xMDC16, was recently cloned from frog (Xenopus laevis) testis and was found to be involved in frog sperm-egg binding. Here we report that xMDC16 is localized predominantly on the posterior surface of egg jelly-activated sperm, and peptides from the disintegrin domain of this protein activate eggs when applied near the egg surface. Egg activation was dependent on (1) specific amino acid residues (KTX); (2) the presence of divalent cations, but not external [Ca.sup.2+] alone; and (3) voltage across the egg plasma membrane. This is the first demonstration of egg activation in vertebrates by the surface application of a peptide derived from a sperm surface protein, supporting a model for egg activation that involves a signal transducing receptor for sperm in the egg's plasma membrane. Key Words: fertilization; disintegrin; integrin; frog; egg activation.

Proteins containing a membrane-anchored metalloprotease domain, a disintegrin domain, and a cysteine-rich region (MDC proteins) are thought to play an important role in mammalian fertilization, as well as in somatic cell-cell interactions. We have identified PCR sequence tags encoding the disintegrin domain of five distinct MDC proteins from Xenopus laevis testis cDNA. Four of these sequence tags (xMDC9, xMDC11.1, xMDC11.2, and xMDC13) showed strong similarity to known mammalian MDC proteins, whereas the fifth (xMDC16) apparently represents a novel family member. Northern blot analysis revealed that the mRNA for xMDC16 was only expressed in testis, and not in heart, muscle, liver, ovaries, or eggs, whereas the mRNAs corresponding to the four other PCR products were expressed in testis and in some or all somatic tissues tested. The xMDC16 protein sequence, as predicted from the full-length cDNA, contains a metalloprotease domain with the active-site sequence HEXXH, a disintegrin domain, a cysteine-rich region, an EGF repeat, a transmembrane domain, and a short cytoplasmic tail. To study a potential role for these xMDC proteins in fertilization, peptides corresponding to the predicted integrin-binding domain of each protein were tested for their ability to inhibit X. laevis fertilization. Cyclic and linear xMDC16 peptides inhibited fertilization in a concentration-dependent manner, whereas xMDC16 peptides that were scrambled or had certain amino acid replacements in the predicted integrin-binding domain did not affect fertilization. Cyclic and linear xMDC9 peptides and linear xMDC13 peptides also inhibited fertilization similarly to xMDC16 peptides, whereas peptides corresponding to the predicted integrin-binding site of xMDC11.1 and xMDC11.2 did not. These results are discussed in the context of a model in which multiple MDC protein-receptor interactions are necessary for fertilization to occur.

The capacity of exogenously involved tyrosine kinase and G-protein coupled receptors to mimic processes of fertilization was analyzed to explore likely pathways for egg activation at fertilization in starfish Asterina miniata. Starfish eggs probably contain elements of a signaling pathway with phospholipase C-gamma and a G-protein and phospholipase C-beta.