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The combustion of perennial grass biomass to generate electricity may be a promising renewable energy option. Switchgrass (Panicum virgatum) grown as a biofuel has the potential to provide a cash crop for farmers and quality nesting cover for grassland birds. In southwestern Wisconsin (near lat. 42 degrees 52', long. 90 degrees 08'), we investigated the impact of an August harvest of switchgrass for bioenergy on community composition and abundance of Wisconsin grassland bird species of management concern. Harvesting the switchgrass in August resulted in changes in vegetation structure and bird species composition the following nesting season. In harvested transects, residual vegetation was shorter and the litter...
We conducted a 2-year field experiment to determine whether archery and muzzleloading hunting seasons caused elk to move prematurely onto private land during late summer. The study site was divided into north and south areas, and each area received both an early- and late-opening treatment. Early-opening treatment was an archery season that opened 1 week earlier (23 Aug) than the historical opening, and late-opening treatment was an archery season that opened 2 weeks later (13 Sep), yielding a 21-day difference in opening dates. We relocated 80 radiocollared female elk, captured at random locations on summer ranges, approximately 2 times per week for a 3-month period surrounding early- and late-opening dates each...
Movement of Rocky Mountain elk (Cervus elaphus nelsoni) to private land in Colorado, USA, is problematic for population management because once on private land, elk are largely unavailable for harvest. We evaluated the relative effects of reducing hunter numbers and changes in opening dates of early-season hunting (archery) on elk movement to private land during a 4-year field experiment. Our study area was divided into north (NTA) and south (STA) treatment areas. Eighty adult female elk were captured and radiomarked during July 1996. From 1996 to 1999, we relocated radiomarked elk 2 times per week for a 2- to 3-month period surrounding archery season opening dates, and we classified each elk location as being on...
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The Randomized Shortest Path (RSP) raster delineates potential dispersal paths for male-mediated gene flow between grizzly bear (Ursus arctos) populations in the Greater Yellowstone Ecosystem (GYE) and the Northern Continental Divide Ecosystem (NCDE). A RSP algorithm was used to estimate the average number of net passages for all grid cells at a spatial resolution of 300 m in the study region which spans parts of Montana, Idaho, and Wyoming. RSP rasters identify potential movement paths for 3 levels of random deviation determined by the parameter Θ (i.e., Θ = 0.01, 0.001, and 0.0001) for bears moving from an origin to a destination node. Lower values of Θ result in greater exploration and more random deviation around...
Humpback chub (Gila cypha) are listed under the Endangered Species Act of 1973, as amended. In accordance with recovery goals finalized in 2002, a population estimate was completed for adult humpback chub in Westwater Canyon on the Colorado River. This population estimate was conducted from 1998 to 2000 with the objectives of obtaining population estimates for humpback chub and roundtail chub in Westwater Canyon. Sampling occurred during September and October throughout the three years of the study. Three passes were conducted annually with approximately one week between passes. The primary method of capture was via trammel netting with supplemental electrofishing on one pass per year. Population estimates were...
A visual impact evaluation method specifically designed to assess landscape alteration as a result of surface mining and quarrying would represent a fundamental aid for both those involved in the early stages of mine planning and design (mining companies) and those in charge of controlling and verifying environmental impacts (government authorities). This research is based on implementation of the visual impact indicator Lvi, which takes into account two parameters among those physically measurable: the extent of visible alteration in the landscape and the chromatic contrast between bare rock and the surrounding environment. Both parameters can be quantified by processing one or more digital images taken from the...
A visual impact evaluation method specifically designed to assess landscape alteration as a result of surface mining and quarrying would represent a fundamental aid for both those involved in the early stages of mine planning and design (mining companies) and those in charge of controlling and verifying environmental impacts (government authorities). This research is based on implementation of the visual impact indicator Lvi, which takes into account two parameters among those physically measurable: the extent of visible alteration in the landscape and the chromatic contrast between bare rock and the surrounding environment. Both parameters can be quantified by processing one or more digital images taken from the...
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288 adult and yearling female elk were captured on 22 Wyoming winter supplemental elk feedgrounds and monitored with GPS collars during the brucellosis risk period (February – July) from 2007 to 2015. There were 4 to 64 individual elk per feedground and each elk was monitored for 1 to 2 years. Here we provide the unique identifier for each individual elk, the GPS location of the elk, the date/time stamp of the GPS location, and the feedground the elk was captured on in Wyoming.
Female big free-tailed bats Nyctinomops macrotis have been captured over water in northern Arizona in high elevation (> 2,400 m) forests and low elevation (1,500 m) desert scrub vegetation. We hypothesized that roost sites were in vertical walls of cliffs that were up to 25 km away from capture sites given the flight capability of these bats. During summer 2005 we captured eight females over ponds and attached radio transmitters to locate day roosts. We also identified locations used during nightly movements from 1 to 6 nights of radio tracking. We found three day roosts for seven bats; average distance (� SE) from a capture site to a roost was 12.1 � 3.0 km. Roosts were small maternity colonies used by ? four N....
Humpback chub (Gila cypha) are listed under the Endangered Species Act of 1973, as amended. In accordance with recovery goals finalized in 2002, population estimates were completed for adult humpback chub in Cataract Canyon on the Colorado River. The sampling was conducted from 2003 to 2005 with the objective of obtaining annual point estimates for humpback in the canyon. Sampling occurred between mid September and early November each of the three years of the study. Three sites were sampled for two nights on three occasions each year with approximately one week between sampling occasion. Approximately 28% (1.9 river miles) of the available habitat in Cataract Canyon was sampled on each occasion. The primary method...
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Acoustic telemetry is a popular tool for the study of fish spatial ecology. In acoustic telemetry, fish are captured, surgically implanted with an acoustic transmitter or ‘tag’, and then released back into the environment. Networks of autonomous, stationary receivers then are used to track the movements of tagged individuals over long periods of time (> 1 year). Each acoustic receiver records the date, time, and unique transmitter code (or ID) for each acoustic tag detection. This data set contains detection data for 282 acoustic-tagged lake sturgeon that were captured and released into the Detroit River, St. Clair River, and Lake Huron between 2011 and 2015. Movements of acoustic-tagged individuals were tracked...
This study demonstratest he correlationo f an arrayo f ecological characteristicsw ith foraging mode in sit-and-wait foraging Crotalus cerastes and widely foraging Masticophis flagellum. Crotalus cerastes are chiefly nocturnal and spend most of their time on the surface either coiled on or partially buried in the sand waiting to ambush prey. Masticophis flagellum are strictly diurnal predators and cruise through the habitat searching for active and sedentary prey. In this study, C. cerastes averaged 7.2 ? 0.7 (SE) h/day on the surface, almost twice the time of M. flagellum (3.9 ? 0.9 h/day). Body temperatures (Tb's) of active M. flagellum, determined from surgically implanted radio transmitters, were significantly...
A visual impact evaluation method specifically designed to assess landscape alteration as a result of surface mining and quarrying would represent a fundamental aid for both those involved in the early stages of mine planning and design (mining companies) and those in charge of controlling and verifying environmental impacts (government authorities). This research is based on implementation of the visual impact indicator Lvi, which takes into account two parameters among those physically measurable: the extent of visible alteration in the landscape and the chromatic contrast between bare rock and the surrounding environment. Both parameters can be quantified by processing one or more digital images taken from the...
Understanding behavioral changes of prey and predators based on lunar illumination provides insight into important life history, behavioral ecology, and survival information. The objectives of this research were to determine if bobcat movement rates differed by period of day (dark, moon, crepuscular, day), lunar illumination (<10%, 10 - <50%, 50 - <90%, >90%), and moon phase (new, full). Bobcats had high movement rates during crepuscular and day periods and low movement rates during dark periods with highest nighttime rates at 10-<50% lunar illumination. Bobcats had highest movement rates during daytime when nighttime illumination was low (new moon) and higher movement rates during nighttime when lunar illumination...
    map background search result map search result map Acoustic telemetry detection data for acoustic-tagged lake sturgeon (Acipenser fulvescens) in the Lake Huron-to-Lake Erie corridor (20161122) Randomized shortest paths for Grizzly Bear dispersal between the GYE and NCDE Elk GPS collar data in southern GYE 2007-2015 Elk GPS collar data in southern GYE 2007-2015 Acoustic telemetry detection data for acoustic-tagged lake sturgeon (Acipenser fulvescens) in the Lake Huron-to-Lake Erie corridor (20161122) Randomized shortest paths for Grizzly Bear dispersal between the GYE and NCDE