Bat response to differing fire severity in mixed-conifer forest California, USA

Wildlife response to natural disturbances such as fire is of conservation concern to managers, policy makers, and scientists, yet information is scant beyond a few well-studied groups (e.g., birds, small mammals). We examined the effects of wildfire severity on bats, a taxon of high conservation concern, at both the stand (<1 ha) and landscape scale in response to the 2002 McNally fire in the Sierra Nevada region of California, USA. One year after fire, we conducted surveys of echolocation activity at 14 survey locations, stratified in riparian and upland habitat, in mixed-conifer forest habitats spanning three levels of burn severity: unburned, moderate, and high. Bat activity in burned areas was either equivalent or higher than in unburned stands for all six phonic groups measured, with four groups having significantly greater activity in at least one burn severity level. Evidence of differentiation between fire severities was observed with some Myotis species having higher levels of activity in stands of high-severity burn. Larger-bodied bats, typically adapted to more open habitat, showed no response to fire. We found differential use of riparian and upland habitats among the phonic groups, yet no interaction of habitat type by fire severity was found. Extent of high-severity fire damage in the landscape had no effect on activity of bats in unburned sites suggesting no landscape effect of fire on foraging site selection and emphasizing stand-scale conditions driving bat activity. Results from this fire in mixed-conifer forests of California suggest that bats are resilient to landscape-scale fire and that some species are preferentially selecting burned areas for foraging, perhaps facilitated by reduced clutter and increased post-fire availability of prey and roost

Are Metropolitan Areas Primed for Success? A Prosperity Risk Index for Evaluating Economic Development Patterns

Urban areas differ greatly in their exposure to economic change, their trajectory toward recovery and growth, and the extent to which development and equity are paired. Some of this differentiation can be explained by regional dynamics, policies, and migration flows that influence the composition of economic activity, land use, and population characteristics. Simultaneously, the fortunes of center cities are known to often correlate with metropolitan characteristics, yet the interaction of socio-spatial conditions with multi-level governance and development processes - particularly with respect to how prosperity is shared across municipal lines and is distributed among communities - is under-researched. In this article, we use a GIS-based and quantitative approach to characterize such patterns and evaluate regional differences among 117 mid-sized metropolitan areas in the Eastern US with a population between 250,000 and 2,500,000. Our analysis rests on initial GIS-based inquiries to define city, urbanized area, county, and core-based statistical area-level measures of municipal fragmentation, geographic sprawl, racial segregation, economic inequality, and overall poverty. These five characteristics are combined to propose a prosperity risk index for each region. Further, indicators of economic performance such as job and population growth are inverted to create an economic vulnerability index. An interaction model is run to determine relationships among the indices to highlight both the regional differences in these characteristics that became noticeably significant in the analysis and the linkages of spatial patterns of economic growth and social equity. Analyzing these multi-scalar regional dynamics illuminates the socio-spatial patterns that deserve attention in urban economic development theory and, subsequently, offers a framework for evaluating public policy and development practices. We likewise offer two comparisons of outliers as a means of illustrating potential directions urban areas can take toward economic development. These findings are valuable for local economic development practitioners who may be seeking further contextual/comparative information on urban regions, or for others interested in understanding the dynamics behind urban planning that may drive regional competitiveness and prosperity

Whole Genomes Inform Genetic Rescue Strategy for Montane Red Foxes in North America.

A few iconic examples have proven the value of facilitated gene flow for counteracting inbreeding depression and staving off extinction; yet, the practice is often not implemented for fear of causing outbreeding depression. Using genomic sequencing, climatic niche modeling, and demographic reconstruction, we sought to assess the risks and benefits of using translocations as a tool for recovery of endangered montane red fox (Vulpes vulpes) populations in the western United States. We demonstrated elevated inbreeding and homozygosity of deleterious alleles across all populations, but especially those isolated in the Cascade and Sierra Nevada ranges. Consequently, translocations would be expected to increase population growth by masking deleterious recessive alleles. Demographic reconstructions further indicated shallow divergences of less than a few thousand years among montane populations, suggesting low risk of outbreeding depression. These genomic-guided findings set the stage for future management, the documentation of which will provide a roadmap for recovery of other data-deficient taxa

A burning question: what are the risks and benefits of mammalian torpor during and after fires?

Although wildfires are increasing globally, available information on how mammals respond behaviourally and physiologically to fires is scant. Despite a large number of ecological studies, often examining animal diversity and abundance before and after fires, the reasons as to why some species perform better than others remain obscure. We examine how especially small mammals, which generally have high rates of energy expenditure and food requirements, deal with fires and postfire conditions. We evaluate whether mammalian torpor, characterised by substantial reductions in body temperature, metabolic rate and water loss, plays a functional role in survival of mammals impacted by fires. Importantly, torpor permits small mammals to reduce their activity and foraging, and to survive on limited food. Torpid small mammals (marsupials and bats) can respond to smoke and arouse from torpor, which provides them with the possibility to evade direct exposure to fire, although their response is often slowed when ambient temperature is low. Post-fire conditions increase expression of torpor with a concomitant decrease in activity for free-ranging echidnas and small forest-dwelling marsupials, in response to reduced cover and reduced availability of terrestrial insects. Presence of charcoal and ash increases torpor use by captive small marsupials beyond food restriction alone, likely in anticipation of detrimental post-fire conditions. Interestingly, although volant bats use torpor on every day after fires, they respond by decreasing torpor duration, and increasing activity, perhaps because of the decrease in clutter and increase in foraging opportunities due to an increase in aerial insects. Our summary shows that torpor is an important tool for post-fire survival and, although the physiological and behavioural responses of small mammals to fire are complex, they seem to reflect energetic requirements and mode of foraging. We make recommendations on the conditions during management burns that are least likely to impact heterothermic mammals

A genome assembly of the American black bear, Ursus americanus, from California

The American black bear, Ursus americanus, is a widespread and ecologically important species in North America. In California, the black bear plays an important role in a variety of ecosystems and serves as an important species for recreational hunting. While research suggests that the populations in California are currently healthy, continued monitoring is critical, with genomic analyses providing an important surveillance tool. Here we report a high-quality, near chromosome-level genome assembly from a U. americanus sample from California. The primary assembly has a total length of 2.5 Gb contained in 316 scaffolds, a contig N50 of 58.9 Mb, a scaffold N50 of 67.6 Mb, and a BUSCO completeness score of 96%. This U. americanus genome assembly will provide an important resource for the targeted management of black bear populations in California, with the goal of achieving an appropriate balance between the recreational value of black bears and the maintenance of viable populations. The high quality of this genome assembly will also make it a valuable resource for comparative genomic analyses among black bear populations and among bear species

Bat Response to Differing Fire Severity in Mixed-Conifer Forest California, USA

Abstract Wildlife response to natural disturbances such as fire is of conservation concern to managers, policy makers, and scientists, yet information is scant beyond a few well-studied groups (e.g., birds, small mammals). We examined the effects of wildfire severity on bats, a taxon of high conservation concern, at both the stand (,1 ha) and landscape scale in response to the 2002 McNally fire in the Sierra Nevada region of California, USA. One year after fire, we conducted surveys of echolocation activity at 14 survey locations, stratified in riparian and upland habitat, in mixed-conifer forest habitats spanning three levels of burn severity: unburned, moderate, and high. Bat activity in burned areas was either equivalent or higher than in unburned stands for all six phonic groups measured, with four groups having significantly greater activity in at least one burn severity level. Evidence of differentiation between fire severities was observed with some Myotis species having higher levels of activity in stands of high-severity burn. Larger-bodied bats, typically adapted to more open habitat, showed no response to fire. We found differential use of riparian and upland habitats among the phonic groups, yet no interaction of habitat type by fire severity was found. Extent of high-severity fire damage in the landscape had no effect on activity of bats in unburned sites suggesting no landscape effect of fire on foraging site selection and emphasizing stand-scale conditions driving bat activity. Results from this fire in mixed-conifer forests of California suggest that bats are resilient to landscapescale fire and that some species are preferentially selecting burned areas for foraging, perhaps facilitated by reduced clutter and increased post-fire availability of prey and roosts

Repeatability in the contact calling system of Spix's disc-winged bat (Thyroptera tricolor)

Spix's disc-winged bat (Thyroptera tricolor) forms cohesive groups despite using an extremely ephemeral roost, partly due to the use of two acoustic signals that help individuals locate roost sites and group embers. While the calls that aid in group cohesion are commonly used, some bats rarely or never produce them. Here, we examine whether the differences observed in the contact calling behaviour of T. tricolor are repeatable; that is, whether individual differences are consistent. We recorded contact calls of individuals in the field and rates and patterns of vocalization. To determine whether measured variables were consistent within individuals, we estimated repeatability (R), which compares within-individual to among-individual variance in behavioural traits. Our results show that repeatability for call variables was moderate but significant, and that repeatability was highest for the average number of calls produced (R=0.46–0.49). Our results demonstrate important individual differences in the contact calling behaviour of T. tricolor; we discuss how these could be the result of mechanisms such as frequency-dependent selection that favour groups composed of individuals with diverse vocal strategies. Future work should address whether changes in social environment, specifically group membership and social status, affect vocal behaviour.UCR::Sedes Regionales::Sede del Su

Tax Credits and Health Insurance for the Self-Employed

This paper will look at how tax credits can help increase the affordability of health insurance among the self-employed in this country. Two of the problems involving health insurance are having enough and being able to afford it. These issues are especially true if you are part of the self-employed population in this country. Many of the self-employed have dropped health coverage or reduced it in the past few years due to rising costs About 24 million of American small business employees and their families are uninsured according to a study by the Kaiser Family Foundation. The research shows that if the self-employed could afford health insurance for their employees the number of uninsured would decrease. The government needs to step in to help make health insurance affordable for the working uninsured. The government has made some proposals that would help lower the costs of health insurance such as, Health Savings Account’s, Flexible Spending Accounts (FSA’s), and President Bush’s Tax Credit Proposal. In my paper I will look at theses as options for helping the self-employed afford health insurance and give my recommendation for a tax credit proposal. Trying to find a way to make health insurance affordable for the self-employed interests me because I have relatives who are self-employed. These relatives pay a high premium for health insurance that is not nearly as comprehensive a plan that you would get from an employer-sponsored plan. Why should someone be subjected to unfair pricing just because they have decided to work for themselves? Many of these countries corporations started out as self-employed entrepreneurs that grew. Offering the self-employed segment of the population a way to afford quality health insurance can only be done with the government’s help

Michael Buchalski's Quick Files

The Quick Files feature was discontinued and it’s files were migrated into this Project on March 11, 2022. The file URL’s will still resolve properly, and the Quick Files logs are available in the Project’s Recent Activity

The Impact Of Redox Stress In Primary Hyperoxaluria Type 1

Primary Hyperoxaluria (PH) is a family of three inborn errors of glyoxylate metabolism resulting in endogenous oxalate overproduction. PH1 is the most common and most severe form of the disorder when compared to PH2 and PH3. PH1 can result in systemic oxalosis or end stage renal disease, and there is currently no cure for this disorder. The only curative treatment is combined liver/kidney transplant. The difficulty in defining a cure for the disorder arises from poor knowledge of the sources of endogenous oxalate and a lack of understanding in the underlying pathophysiology of the disorder. For these reasons, we have focused on two approaches to investigate the gaps in knowledge of this disorder. The first, involved targeting the hydroxyproline metabolic pathway, a known source of oxalate, as a therapeutic option for limiting endogenous oxalate production. To investigate this pathway, we developed a hydroxyproline dehydrogenase (HYPDH) KO mouse, along with CHO.HYPDH liver derived cell lines that we have characterized in respect to responses to hydroxyproline exposure. Second, we performed a global proteomics study on PH1 mouse model liver to investigate the underlying pathophysiology of PH1, which is characterized by a loss of activity mutation of alanine: glyoxylate aminotransferase (Agxt). A rigorous study on the effects on absence of Agxt in the liver had previously not yet been performed. The liver is not classically considered an organ of interest in PH1 as there is no phenotypic difference between a PH1 liver and a healthy liver. However, in contrast, we observed significant differences in the Agxt liver proteome including a subtle perturbation in the redox proteome supported by transcriptomic data and GSH measurements. A global proteomics approach combined with more traditional oxidative stress methods revealed previously unappreciated chronic, low level oxidative stress in the PH1 mouse that either method alone would have missed. These findings represent new options for therapeutic treatment of PH1 that could increase the quality of life for PH1 patients