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We develop a novel spatial-dynamic model of landowners managing a disease in a perennial crop. We use the model to investigate the dynamic gains from cooperation to address the spatial externality resulting from disease vector dispersal. We find that solving for the complete time path of control decisions is important; cooperation leads to each landowner investing more in treatment in early years than in cases where one agent free rides on the other's control. Our model is based on Pierce's Disease of grapevines in California's Napa Valley but is applicable to a range of diseases in perennial crops.

Some have suggested that the US food stamp program (FSP) should be revised with a view to combating obesity among the poor. In this paper, we assess the likely impacts of allowing FSP participants to purchase only healthy foods when using food stamps. Our results indicate that FSP participants would probably increase their consumption of healthy food, but the implications for their purchases of unhealthy food are not clear. Market-wide consequences are even less clear, because changing what may be purchased using food stamps would lead to higher prices for healthy foods and lower prices for unhealthy foods and these price effects would feed back into consumer decisions, with adverse effects on consumption patterns of both participants and non-participants in the FSP. In addition, more restrictive rules on the use of food stamps would discourage participation in the FSP. We conclude that, while reforming the FSP may indeed to lead to better diets among participants, it is likely to be an ineffective and inefficient instrument for bringing about desired nutritional outcomes unless accompanied by additional policy instruments. © 2008 Elsevier Ltd. All rights reserved.

Wildlife must adapt to human presence to survive in the Anthropocene, so it is critical to understand species responses to humans in different contexts. We used camera trapping as a lens to view mammal responses to changes in human activity during the COVID-19 pandemic. Across 163 species sampled in 102 projects around the world, changes in the amount and timing of animal activity varied widely. Under higher human activity, mammals were less active in undeveloped areas but unexpectedly more active in developed areas while exhibiting greater nocturnality. Carnivores were most sensitive, showing the strongest decreases in activity and greatest increases in nocturnality. Wildlife managers must consider how habituation and uneven sensitivity across species may cause fundamental differences in human-wildlife interactions along gradients of human influence., (© 2024. The Author(s).)

Managing wildlife populations in the face of global change requires regular data on the abundance and distribution of wild animals, but acquiring these over appropriate spatial scales in a sustainable way has proven challenging. Here we present the data from Snapshot USA 2020, a second annual national mammal survey of the USA. This project involved 152 scientists setting camera traps in a standardized protocol at 1485 locations across 103 arrays in 43 states for a total of 52,710 trap-nights of survey effort. Most (58) of these arrays were also sampled during the same months (September and October) in 2019, providing a direct comparison of animal populations in 2 years that includes data from both during and before the COVID-19 pandemic. All data were managed by the eMammal system, with all species identifications checked by at least two reviewers. In total, we recorded 117,415 detections of 78 species of wild mammals, 9236 detections of at least 43 species of birds, 15,851 detections of six domestic animals and 23,825 detections of humans or their vehicles. Spatial differences across arrays explained more variation in the relative abundance than temporal variation across years for all 38 species modeled, although there are examples of significant site-level differences among years for many species. Temporal results show how species allocate their time and can be used to study species interactions, including between humans and wildlife. These data provide a snapshot of the mammal community of the USA for 2020 and will be useful for exploring the drivers of spatial and temporal changes in relative abundance and distribution, and the impacts of species interactions on daily activity patterns. There are no copyright restrictions, and please cite this paper when using these data, or a subset of these data, for publication., (© 2022 The Authors. Ecology © 2022 The Ecological Society of America.)

Homeothermy requires increased metabolic rates as temperatures decline below the thermoneutral zone, so homeotherms typically select microhabitats within or near their thermoneutral zones during periods of inactivity. However, many mammals and birds are heterotherms that relax internal controls on body temperature and go into torpor when maintaining a high, stable body temperature, which is energetically costly. Such heterotherms should be less tied to microhabitats near their thermoneutral zones and, because heterotherms spend more time in torpor and expend less energy at colder temperatures, heterotherms may even select microhabitats in which temperatures are well below their thermoneutral zones. We studied how temperature and daily torpor influence the selection of microhabitats (i.e., diurnal roosts) by a heterothermic bat (Myotis thysanodes). We (1) quantified the relationship between ambient temperature and daily duration of torpor, (2) simulated daily energy expenditure over a range of microhabitat temperatures, and (3) quantified the influence of microhabitat temperature on microhabitat selection. In addition, warm microhabitats substantially reduced the energy expenditure of simulated homeothermic bats, and heterothermic bats modulated their use of daily torpor to maintain a constant level of energy expenditure across microhabitats of different temperatures. Daily torpor expanded the range of energetically economical microhabitats, such that microhabitat selection was independent of microhabitat temperature. Our work adds to a growing literature documenting the functions of torpor beyond its historical conceptualization as a last-resort measure to save energy during periods of extended or acute energetic stress., (© 2022 The Authors. Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

Diverse communities of large mammalian herbivores (LMH), once widespread, are now rare. LMH exert strong direct and indirect effects on community structure and ecosystem functions, and measuring these effects is important for testing ecological theory and for understanding past, current, and future environmental change. This in turn requires long-term experimental manipulations, owing to the slow and often nonlinear responses of populations and assemblages to LMH removal. Moreover, the effects of particular species or body-size classes within diverse LMH guilds are difficult to pinpoint, and the magnitude and even direction of these effects often depends on environmental context. Since 2008, we have maintained the Ungulate Herbivory Under Rainfall Uncertainty (UHURU) experiment, a series of size-selective LMH exclosures replicated across a rainfall/productivity gradient in a semiarid Kenyan savanna. The goals of the UHURU experiment are to measure the effects of removing successively smaller size classes of LMH (mimicking the process of size-biased extirpation) and to establish how these effects are shaped by spatial and temporal variation in rainfall. The UHURU experiment comprises three LMH-exclusion treatments and an unfenced control, applied to nine randomized blocks of contiguous 1-ha plots (n = 36). The fenced treatments are MEGA (exclusion of megaherbivores, elephant and giraffe), MESO (exclusion of herbivores ≥40 kg), and TOTAL (exclusion of herbivores ≥5 kg). Each block is replicated three times at three sites across the 20-km rainfall gradient, which has fluctuated over the course of the experiment. The first 5 years of data were published previously (Ecological Archives E095-064) and have been used in numerous studies. Since that publication, we have (1) continued to collect data following the original protocols, (2) improved the taxonomic resolution and accuracy of plant and small-mammal identifications, and (3) begun collecting several new data sets. Here, we present updated and extended raw data from the first 12 years of the UHURU experiment (2008-2019). Data include daily rainfall data throughout the experiment; annual surveys of understory plant communities; annual censuses of woody-plant communities; annual measurements of individually tagged woody plants; monthly monitoring of flowering and fruiting phenology; every-other-month small-mammal mark-recapture data; and quarterly large-mammal dung surveys. There are no copyright restrictions; notification of when and how data are used is appreciated and users of UHURU data should cite this data paper when using the data., (© 2022 The Authors. Ecology © 2022 The Ecological Society of America.)

The extinction of 80% of megaherbivore (>1,000 kg) species towards the end of the Pleistocene altered vegetation structure, fire dynamics and nutrient cycling world-wide. Ecologists have proposed (re)introducing megaherbivores or their ecological analogues to restore lost ecosystem functions and reinforce extant but declining megaherbivore populations. However, the effects of megaherbivores on smaller herbivores are poorly understood. We used long-term exclusion experiments and multispecies hierarchical models fitted to dung counts to test (a) the effect of megaherbivores (elephant and giraffe) on the occurrence (dung presence) and use intensity (dung pile density) of mesoherbivores (2-1,000 kg), and (b) the extent to which the responses of each mesoherbivore species was predictable based on their traits (diet and shoulder height) and phylogenetic relatedness. Megaherbivores increased the predicted occurrence and use intensity of zebras but reduced the occurrence and use intensity of several other mesoherbivore species. The negative effect of megaherbivores on mesoherbivore occurrence was stronger for shorter species, regardless of diet or relatedness. Megaherbivores substantially reduced the expected total use intensity (i.e. cumulative dung density of all species) of mesoherbivores, but only minimally reduced the expected species richness (i.e. cumulative predicted occurrence probabilities of all species) of mesoherbivores (by <1 species). Simulated extirpation of megaherbivores altered use intensity by mesoherbivores, which should be considered during (re)introductions of megaherbivores or their ecological proxies. Species' traits (in this case shoulder height) may be more reliable predictors of mesoherbivores' responses to megaherbivores than phylogenetic relatedness, and may be useful for predicting responses of data-limited species., (© 2021 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.)

With the accelerating pace of global change, it is imperative that we obtain rapid inventories of the status and distribution of wildlife for ecological inferences and conservation planning. To address this challenge, we launched the SNAPSHOT USA project, a collaborative survey of terrestrial wildlife populations using camera traps across the United States. For our first annual survey, we compiled data across all 50 states during a 14-week period (17 August-24 November of 2019). We sampled wildlife at 1,509 camera trap sites from 110 camera trap arrays covering 12 different ecoregions across four development zones. This effort resulted in 166,036 unique detections of 83 species of mammals and 17 species of birds. All images were processed through the Smithsonian's eMammal camera trap data repository and included an expert review phase to ensure taxonomic accuracy of data, resulting in each picture being reviewed at least twice. The results represent a timely and standardized camera trap survey of the United States. All of the 2019 survey data are made available herein. We are currently repeating surveys in fall 2020, opening up the opportunity to other institutions and cooperators to expand coverage of all the urban-wild gradients and ecophysiographic regions of the country. Future data will be available as the database is updated at eMammal.si.edu/snapshot-usa, as will future data paper submissions. These data will be useful for local and macroecological research including the examination of community assembly, effects of environmental and anthropogenic landscape variables, effects of fragmentation and extinction debt dynamics, as well as species-specific population dynamics and conservation action plans. There are no copyright restrictions; please cite this paper when using the data for publication., (© 2021 The Authors. Ecology © 2021 The Ecological Society of America.)

In this article we use an economic model to link markets for agricultural commodities to food-product markets, and to trace the effects of agricultural policies on prices of food products and, consequently, on food consumption and calorie intake. Contrary to common claims, US agricultural policies have had generally modest and mixed effects on prices and quantities of farm commodities, with negligible effects on the prices paid by consumers for food, and thus a negligible influence on dietary patterns and obesity., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Many commentators have speculated that agricultural policies have contributed to increased obesity rates in the United States, yet such claims are often made without any analysis of the complex links between real-world farm commodity support programs, prices and consumption of foods, and caloric intake. This article carefully studies the effects of US agricultural policies on prices and quantities of 10 agricultural commodities and nine food categories in the United States over time. Using a detailed multimarket model, we simulate the counterfactual removal of measures of support applied to US agricultural commodities in 1992, 1997, and 2002 and quantify the effects on US food consumption and caloric intake. To parameterize the simulations, we calculate three alternative measures of consumer support (the implicit consumer subsidy from policies that support producers) for the 10 agricultural commodities using information about government expenditures on agricultural commodities from various sources. Our results indicate that-holding all other policies constant-removing US subsidies on grains and oilseeds in the three periods would have caused caloric consumption to decrease minimally whereas removal of all US agricultural policies (including barriers against imports of sugar and dairy products) would have caused total caloric intake to increase. Our results also indicate that the influence of agricultural policies on caloric intake has diminished over time., (Copyright © 2012 John Wiley & Sons, Ltd.)

Adolf Weil defined the disease as a clinical entity in 1886, and Leptospira ictero-haemorrhagiae was found to be the causative organism in 1915 by Inada et al. in Japan, and confirmed by Hübener and Reiter in Germany. The infection has been found in most countries, and recently there has been a great increase in the number of instances reported.In most parts of the world rats and other small rodents harbour the organism and excrete it in the urine. This is almost always the direct or indirect source of infection of man, but natural infection of dogs and foxes takes place, and is at least a potential danger to human beings. Infection is usually related to occupation in coal-mines, field work of all sorts, sewers, fish-cleaning, and to bathing in fresh water.The organism quickly dies in an acid medium, in strong sunlight and in salt water. These facts accord with the presence of the disease in certain situations.The route of infection of man is usually by contact of the abraded or sodden skin with infected mud or water, but it may be by inhalation of water and by bites of rats, dogs, and ferrets.Men are much more exposed to infection than women, but in fish-cleaners the incidence is equal in the sexes. Children are sometimes infected by bathing and in houses.The incubation time may be four to nineteen days, and is usually seven to thirteen days.By serological methods many unjaundiced and subclinical infections can be detected among people who are often at risk, and these correct the rather high fatality rates which are derived from jaundiced cases only.During the last three and a half years 142 authenticated instances of the disease in an obvious clinical form have been reported in the British Isles. Twenty-one occupations or circumstances were involved, and the case fatality rate was 15 per cent.

From its known properties "soframycin" appears to be valuable for intestinal antisepsis since it has a broad spectrum. The intestinal bacteria are sensitive to it, it acts rapidly, is poorly absorbed from the gastrointestinal tract, and is well tolerated by mouth.