42 research outputs found

    Is there anybody out there? Occupancy of the carnivore guild in a temperate archipelago

    Get PDF
    Carnivores are important components of ecological communities with wide-ranging effects that vary with carnivore size, natural history, and hunting tactics. Researchers and managers should strive to understand both the presence and distribution of carnivores within their local environment. We studied the carnivore guild in the Apostle Islands, where the distribution and occupancy of carnivores was largely unknown. We monitored 19 islands with 160 functioning camera traps from 2014-2017, from which we collected 203,385 photographs across 49,280 trap nights. We documented 7,291 total wildlife events with 1,970 carnivore events, and detected 10 of the 12 terrestrial carnivores found in Wisconsin. Detection rates for species were generally higher in summer than winter, except for coyotes (Canis latrans) and red foxes (Vulpes vulpes). Finitesample occupancy estimates for carnivores varied across islands, with mean estimated occupancy across islands varying from a high of 0.73 for black bears to a low of 0.21 for gray wolves. Of the potential island biogeography explanatory variables for carnivore occupancy we considered, island size was the most important, followed by distance to the mainland, and then interisland distance. We estimated that terrestrial carnivore species varied in the number of islands they were detected on from 1 island for gray wolves to 13 islands for black bears. Estimated carnivore richness across islands (i.e., the number of carnivores occupying an island) also varied substantively from 1 species on Michigan Island to 10 species on Stockton Island. Island size and connectivity between islands appear important for the persistence of the carnivore community in the Apostle Islands

    Terrestrial habitat requirements of nesting freshwater turtles

    Get PDF
    Because particular life history traits affect species vulnerability to development pressures, cross-species summaries of life history traits are useful for generating management guidelines. Conservation of aquatic turtles, many members of which are regionally or globally imperiled, requires knowing the extent of upland habitat used for nesting. Therefore, we compiled distances that nests and gravid females had been observed from wetlands. Based on records of \u3e 8000 nests and gravid female records compiled for 31 species in the United States and Canada, the distances that encompass 95% of nests vary dramatically among genera and populations, from just 8 m for Malaclemys to nearly 1400 m for Trachemys. Widths of core areas to encompass varying fractions of nesting populations (based on mean maxima across all genera) were estimated as: 50% coverage = 93 m, 75% = 154 m, 90% = 198 m, 95% = 232 m, 100% = 942 m. Approximately 6–98 m is required to encompass each consecutive 10% segment of a nesting population up to 90% coverage; thereafter, ca. 424 m is required to encompass the remaining 10%. Many genera require modest terrestrial areas (\u3c200 m zones) for 95% nest coverage (Actinemys, Apalone, Chelydra, Chrysemys, Clemmys, Glyptemys, Graptemys, Macrochelys, Malaclemys, Pseudemys, Sternotherus), whereas other genera require larger zones (Deirochelys, Emydoidea, Kinosternon, Trachemys). Our results represent planning targets for conserving sufficient areas of uplands around wetlands to ensure protection of turtle nesting sites, migrating adult female turtles, and dispersing turtle hatchlings

    The Physics of Star Cluster Formation and Evolution

    Get PDF
    © 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00689-4.Star clusters form in dense, hierarchically collapsing gas clouds. Bulk kinetic energy is transformed to turbulence with stars forming from cores fed by filaments. In the most compact regions, stellar feedback is least effective in removing the gas and stars may form very efficiently. These are also the regions where, in high-mass clusters, ejecta from some kind of high-mass stars are effectively captured during the formation phase of some of the low mass stars and effectively channeled into the latter to form multiple populations. Star formation epochs in star clusters are generally set by gas flows that determine the abundance of gas in the cluster. We argue that there is likely only one star formation epoch after which clusters remain essentially clear of gas by cluster winds. Collisional dynamics is important in this phase leading to core collapse, expansion and eventual dispersion of every cluster. We review recent developments in the field with a focus on theoretical work.Peer reviewe

    Treatment of chancroid : a comparison of sulfamethoxazole and trimethoprim / sulfamethoxazole

    No full text
    Photocop
    corecore