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Christopher S. Deperno - One of the best experts on this subject based on the ideXlab platform.
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White-tailed deer use of overstory hardwoods in longleaf pine woodlands
Forest Ecology and Management, 2020Co-Authors: Anthony J. Kroeger, Christopher E. Moorman, Marcus A. Lashley, M. Colter Chitwood, Craig A. Harper, Christopher S. DepernoAbstract:Abstract Restoration of the longleaf pine ecosystem is a conservation priority throughout the southeastern United States, but the role of hardwoods in providing food and cover for wildlife within this system is poorly understood. We investigated white-tailed deer (Odocoileus virginianus) movement and habitat selection relative to overstory hardwood distribution in a longleaf pine ecosystem at Fort Bragg Military Installation in the Sandhills physiographic region of North Carolina from March 2011–July 2013. We monitored GPS-collared female white-tailed deer and used generalized linear mixed models and step-selection functions to determine the influence of overstory composition and understory cover on seasonal white-tailed deer habitat selection. During fall and winter, deer selection increased with increasing upland hardwood overstory until reaching an upper threshold (12% and 7%; respectively) where increasing cover of upland hardwoods no longer increased selection. Also, in the fall and winter, deer selected areas with greater bottomland hardwood overstory until an upper threshold of 33% bottomland hardwood overstory was reached. In the spring, deer selected areas with
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survival and cause specific mortality of coyotes on a large Military Installation
Southeastern Naturalist, 2016Co-Authors: Elizabeth Rose Stevenson, Christopher E. Moorman, Marcus A. Lashley, Colter M Chitwood, Kenneth H Pollock, Morgan B Swingen, Christopher S. DepernoAbstract:Abstract Canis latrans (Coyote) recently expanded into the southeastern United States, creating ecologically novel interactions with other species. However, relatively few studies have examined vital rates of southeastern Coyotes or estimated vital rates where individuals are protected from hunting and trapping. In 2011, we captured and attached GPS radiocollars to 31 Coyotes at Fort Bragg Military Installation, NC, where Coyote harvest was restricted. We used a 12-month period (February 2011–January 2012) and known-fate modeling in Program MARK to estimate annual survival. Model-selection results indicated the time-varying model (S[t]) was the most parsimonious model, and. annual survival was 0.80 (95% CI = 0.60–0.91). We documented 7 mortalities, including 2 from vehicles, 2 from offsite trapping, and 3 from unknown causes. Estimated Coyote survival rates at Fort Bragg were similar to most other estimates from the southeastern US. Anthropogenic causes of mortality were important even though hunting and ...
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white tailed deer population dynamics and adult female survival in the presence of a novel predator
Journal of Wildlife Management, 2015Co-Authors: M. Colter Chitwood, Christopher E. Moorman, Marcus A. Lashley, John C Kilgo, Christopher S. DepernoAbstract:Recent localized declines in white-tailed deer (Odocoileus virginianus) populations in the southeastern United States have been linked to increasing predation pressure from coyotes (Canis latrans), a novel predator to the region. Studies have documented coyotes as the leading cause of mortality for neonates, and 1 study documented coyotes as a mortality factor for adult females. However, no study has used field-based vital rates to conduct sensitivity analyses or model deer population trajectories under potential harvest or predator removal strategies. We used low, medium, and high values of fawn survival, adult female survival, and fecundity data collected from Fort Bragg Military Installation, North Carolina to demonstrate the current declining population trajectory for deer (λ = 0.905; low λ = 0.788, high λ = 1.003). Consistent with other studies of ungulates, we determined adult female survival was the most sensitive and elastic vital rate. Further, for 3 potential management (“what if”) scenarios, we projected the population for 10 years using estimated vital rates. Reducing adult female harvest (λ = 0.935; low λ = 0.875, high λ = 1.002) and coyote removal (λ = 0.995; low λ = 0.898, high λ = 1.081) reduced the current population decline, whereas combining both approaches (λ = 1.024; low λ = 0.898, high λ = 1.141) resulted in population increases. Our data indicate that for low-density deer populations with heavy predation pressure on neonates, protecting adult females from harvest may not completely offset population declines. Coyote removal might be a necessary strategy because it could possibly increase very low fawn survival, which appears to be the most important vital rate influencing λ in our study. However, managers may have to start with reductions in adult female harvest because coyote removal would have to be continuous and consistently effective, making it an impractical management approach by itself. © 2015 The Wildlife Society.
David Levine - One of the best experts on this subject based on the ideXlab platform.
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a time for presidential power war time and the constrained executive
Michigan Law Review, 2013Co-Authors: David LevineAbstract:A TIME FOR PRESIDENTIAL POWER? WAR TIME AND THE CONSTRAINED EXECUTIVE WAR TIME: AN IDEA, ITS HISTORY, ITS CONSEQUENCES. By Mary L. Dudziak. Oxford and New York: Oxford University Press. 2012. Pp. 136. $24.95.INTRODUCTIONBetween 2002 and 2008 I served as an intelligence officer in the U.S. Air Force. Though I had been deployed overseas several times, my primary place of duty was in the United States. When I landed at Baghdad International Airport in June 2006, however, several things immediately changed for me as a result of Military regulations. I had to carry my sidearm and dog tags at all times. I could not eat anywhere other than a U.S. Military Installation. I could not drink alcohol. My pay was a bit higher. Personally, I was more vigilant, more aware of my surroundings. In other words, I was at war.Indeed, the U.S. government claimed wartime powers because thousands of others like me-members of the U.S. Military-were stationed in Iraq: the United States deployed large numbers of troops to provisional bases on foreign soil, those troops used lethal force, and they detained individuals without trial for using force in return. And while there was a reasonably clear beginning point for the exercise of these powers-found in an Authorization for the Use of Military Force ("AUMF") rather than a formal declaration of war1-from the vantage point of June 2006, it was unclear whether or when this authority would cease. There was no enemy that could surrender or sign a peace treaty, or give some other sign that "war" had ended; the forces that the United States was fighting-variously, Sunni tribesmen, Shia militias, and foreign extremists-had changed significantly since the 2003 invasion and would even change during my yearlong deployment. Although, as an officer in the U.S. Military, it was very clear for me when I was at war and when I was not, the temporal bounds of this "wartime" were actually quite murky for the U.S. government. That murkiness increased significantly when considering not only the war in Iraq but also the "Global War on Terror" writ large.Professor Mary L. Dudziak's important new book War Time2 confronts the murkiness between wartime and peacetime, investigating its history, present reality, and implications. Although the boundaries of the War on Terror are commonly perceived as shifting and uncertain, especially compared to relatively defined wars such as World War II, Dudziak argues that the murky boundaries of war are not a new phenomenon and highlights the corrosive effects that such uncertainty can have on the rule of law. She argues that this uncertainty will accelerate as the United States engages in increasingly amorphous armed conflicts. She likewise predicts that political leaders-particularly executive branch officials-will try to take advantage of wartime's uncertain boundaries while using the terminology of a more certain past.Dudziak contends that the increasing invocation of wartime as an argument for increased executive power runs counter to the conception of the United States as a nation of laws. She suggests that we need to understand the flawed rationale behind such invocations to effectively combat them. Part I of this Notice summarizes Dudziak's work, tracing the development of the modern concept of "wartime" from World War II to the present day. Parts II and III evaluate Dudziak's arguments in light of two of the most extraordinary powers that a state may claim in wartime-the power to detain and the power to project force. Part II argues that, for all of Dudziak's concerns about the diminishing barriers between peacetime and wartime, there still exist some hard limits on the power that the executive may claim, as evidenced by U.S. detention policies in Iraq. But while some limits may still apply, Part III also finds truth in Dudziak's premise that wartime's boundaries are eroding, using the recent U.S. intervention in Libya as an example. Part III also examines the limits to Dudziak's paradigm, under which wartime necessarily equals government power, against the backdrop of a president who has expanded his power by conspicuously avoiding "wartime. …
Robert H Melton - One of the best experts on this subject based on the ideXlab platform.
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response of red cockaded woodpeckers to Military training operations
Wildlife Monographs, 2011Co-Authors: David K Delaney, Larry L. Pater, Lawrence D. Carlile, Eric W Spadgenske, Timothy A Beaty, Robert H MeltonAbstract:Military lands are a valuable resource in recovery of threatened, endangered, and at-risk species worldwide and have the highest density of threatened and endangered species of all major land management agencies in the United States. Many red-cockaded woodpeckers (Picoides borealis )t hat reside on federal lands occur on 15 Military Installations in the southeastern United States. This close association has increased concern over potential conflicts between conservation requirements of endangered species and the Military's mission of combat readiness. Our objectives were to 1) determine if Military training operations affect behavior, reproductive success, and productivity of red-cockaded woodpeckers; 2) develop a frequency-weighting function to assess woodpecker hearing sensitivity; 3) identify factors that affect woodpecker responses to Military training operations; 4) develop distance and dose-response thresholds for quantifying woodpecker responses to noise levels and stimulus distances; 5) characterize Military training operations through quantification of sound levels, source identification, distance from active woodpecker nests, frequency spectra, duration, and frequency of occurrence; and 6) document baseline woodpecker nesting behavior. We conducted our study on the Fort Stewart Military Installation located in southeast Georgia, USA. Downy woodpeckers, as surrogates for red-cockaded woodpeckers, had their best hearing sensitivity within the peak range of the power spectrum of both downy and red-cockaded woodpecker vocalizations, which is at a higher frequency than that of a typical passerine. Overall, woodpeckers had a reduced auditory sensitivity relative to human hearing sensitivity and other species of small birds, especially in the frequency range >4 kHz. Woodpeckers were most sensitive in the 1.5- to 4.0-kHz range. Sensitivity appeared to drop off quickly at frequencies 4.0 kHz. Overall, we did not find that the woodpecker-frequency-weighting function we developed provided a better predictor of woodpecker flush response compared with A-weighting. More research is needed to better understand the relationship between frequency-weighting functions and woodpecker response behavior. Potential breeding groups of woodpeckers across the population increased from 158 in 1997 to 181 in 2000, wheras nesting groups increased from 141 in 1998 to 170 in 2000, for overall increases of 14.6% and 20.6%, respectively, over the 3 years of this project. Fledging success rates for individual nests within the overall population remained consistent from 1998 to 2000, averaging 84.4%. Mean clutch sizes for woodpecker groups for 1998 to 2000 ranged from 2.75 to 3.01 eggs/nest, brood size ranged from 2.01 to 2.22 nestlings/nest, whereas the average number of young fledged ranged from 1.57 to 1.76 young/ occupied nest. We observed no difference in reproductive success or productivity between experimental and control-tested red-cockaded woodpecker groups. Overall, experimental test groups produced an average of 2.98 eggs/nest, 1.89 nestlings/nest, and 1.54 young/occupied nest from 1999 to 2000, compared with 2.73 eggs/nest, 1.91 nestlings/nest, and 1.57 young/occupied nest at control groups. We measured behavioral responses (nest attendance and arrivals and departures from the nest) of red-cockaded woodpeckers to Military training events through direct and indirect (i.e., video surveillance) observation of 464.5 hours of woodpecker nesting behavior before and after controlled experimental events while recording and characterizing Military-generated sound events using sound-recording equipment. We presented woodpeckers with actual 0.50- caliber blank machine gun fire and artillery simulators from controlled distances to develop distance and sound thresholds. We used video surveillance to document potential behavioral responses of woodpeckers primarily during nonexperimental Military training operations in areas that could not be safely monitored and to determine baseline woodpecker nesting behaviors. We recorded 2,846 nonexperimental Military noise events in 157 data sessions at 50 red-cockaded woodpecker groups from 1998 to 2000. We also recorded 206 experimental tests at 58 woodpecker groups during 1999 and 2000. Life-table analyses of flush response time showed that at short ranges (15-30 m) the flush response was stronger for artillery simulator blasts than for blank fire in both the incubation and the nestling phases. In contrast, at medium distances (45-60 m) blank fire tended to produce more flush responses than artillery fire in both incubation and nestling phases. At longer distances (>60 m), blank fire and artillery produced similar flush responses in the incubation phase, whereas flush response was stronger for blank fire than for artillery in the nestling phase. In general, most animals that responded to Military activity flushed within 5 seconds of the stimulus event. Woodpeckers returned to nests within an average of 4.4 minutes after being flushed by artillery simulators and 6.3 minutes after 0.50-caliber blank-fire tests. Woodpecker flush response rates increased as stimulus distance decreased and sound levels increased, regardless of stimulus type or year. Woodpeckers did not flush from nests when 0.50-caliber blank machine gun fire and artillery simulators were >152 m away and sound-exposure levels (decibels (dB)) were <68 dBW (woodpecker-based frequency-weighting curve) and <65 dBW, respectively. We found that blast treatments reduced arrival rates of adults at the nest, with the amount of reduction dependent on the type of blast stimulus and number of helpers at the nest. On the other hand, blast treatments had no detectable effects on nest attendance. The effect of blank fire on incubation- phase arrivals over a 30-minute interval (about 40% reduction) was nearly twice that of artillery simulator fire (about a 20% reduction). There was no evidence supporting any effect of stimulus type on arrivals during the nestling phase. Blast stimuli during incubation reduced arrivals by 40% when no helpers were present, but the strength of this effect decreased to 28% when one helper was present, and was only 6% for nests with � 2 helpers. Distance of the blast from the nest did not affect the response of arrival rates to blast treatments. Infrequent, short-duration Military training exercises, as measured, did not appear to substantially impact red-cockaded woodpecker reproductive success and productivity on the Fort Stewart Military Installation. Our results may be applicable to other Military Installations where similar training activities and intensity levels occur. Additional research is needed to address possible habituation or sensitization of red-cockaded woodpeckers to human activities in proximity to active nest sites. Although we attempted to monitor woodpecker response to a number of Military training activities, other types of Military training operations or human-based activities with louder noise, longer duration, increased human presence, and greater frequency of occurrence could more negatively influence woodpecker nesting behavior and need to be investigated. Our results do not support the hypothesis that Military
Anthony J. Kroeger - One of the best experts on this subject based on the ideXlab platform.
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White-tailed deer use of overstory hardwoods in longleaf pine woodlands
Forest Ecology and Management, 2020Co-Authors: Anthony J. Kroeger, Christopher E. Moorman, Marcus A. Lashley, M. Colter Chitwood, Craig A. Harper, Christopher S. DepernoAbstract:Abstract Restoration of the longleaf pine ecosystem is a conservation priority throughout the southeastern United States, but the role of hardwoods in providing food and cover for wildlife within this system is poorly understood. We investigated white-tailed deer (Odocoileus virginianus) movement and habitat selection relative to overstory hardwood distribution in a longleaf pine ecosystem at Fort Bragg Military Installation in the Sandhills physiographic region of North Carolina from March 2011–July 2013. We monitored GPS-collared female white-tailed deer and used generalized linear mixed models and step-selection functions to determine the influence of overstory composition and understory cover on seasonal white-tailed deer habitat selection. During fall and winter, deer selection increased with increasing upland hardwood overstory until reaching an upper threshold (12% and 7%; respectively) where increasing cover of upland hardwoods no longer increased selection. Also, in the fall and winter, deer selected areas with greater bottomland hardwood overstory until an upper threshold of 33% bottomland hardwood overstory was reached. In the spring, deer selected areas with
Marcus A. Lashley - One of the best experts on this subject based on the ideXlab platform.
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White-tailed deer use of overstory hardwoods in longleaf pine woodlands
Forest Ecology and Management, 2020Co-Authors: Anthony J. Kroeger, Christopher E. Moorman, Marcus A. Lashley, M. Colter Chitwood, Craig A. Harper, Christopher S. DepernoAbstract:Abstract Restoration of the longleaf pine ecosystem is a conservation priority throughout the southeastern United States, but the role of hardwoods in providing food and cover for wildlife within this system is poorly understood. We investigated white-tailed deer (Odocoileus virginianus) movement and habitat selection relative to overstory hardwood distribution in a longleaf pine ecosystem at Fort Bragg Military Installation in the Sandhills physiographic region of North Carolina from March 2011–July 2013. We monitored GPS-collared female white-tailed deer and used generalized linear mixed models and step-selection functions to determine the influence of overstory composition and understory cover on seasonal white-tailed deer habitat selection. During fall and winter, deer selection increased with increasing upland hardwood overstory until reaching an upper threshold (12% and 7%; respectively) where increasing cover of upland hardwoods no longer increased selection. Also, in the fall and winter, deer selected areas with greater bottomland hardwood overstory until an upper threshold of 33% bottomland hardwood overstory was reached. In the spring, deer selected areas with
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survival and cause specific mortality of coyotes on a large Military Installation
Southeastern Naturalist, 2016Co-Authors: Elizabeth Rose Stevenson, Christopher E. Moorman, Marcus A. Lashley, Colter M Chitwood, Kenneth H Pollock, Morgan B Swingen, Christopher S. DepernoAbstract:Abstract Canis latrans (Coyote) recently expanded into the southeastern United States, creating ecologically novel interactions with other species. However, relatively few studies have examined vital rates of southeastern Coyotes or estimated vital rates where individuals are protected from hunting and trapping. In 2011, we captured and attached GPS radiocollars to 31 Coyotes at Fort Bragg Military Installation, NC, where Coyote harvest was restricted. We used a 12-month period (February 2011–January 2012) and known-fate modeling in Program MARK to estimate annual survival. Model-selection results indicated the time-varying model (S[t]) was the most parsimonious model, and. annual survival was 0.80 (95% CI = 0.60–0.91). We documented 7 mortalities, including 2 from vehicles, 2 from offsite trapping, and 3 from unknown causes. Estimated Coyote survival rates at Fort Bragg were similar to most other estimates from the southeastern US. Anthropogenic causes of mortality were important even though hunting and ...
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white tailed deer population dynamics and adult female survival in the presence of a novel predator
Journal of Wildlife Management, 2015Co-Authors: M. Colter Chitwood, Christopher E. Moorman, Marcus A. Lashley, John C Kilgo, Christopher S. DepernoAbstract:Recent localized declines in white-tailed deer (Odocoileus virginianus) populations in the southeastern United States have been linked to increasing predation pressure from coyotes (Canis latrans), a novel predator to the region. Studies have documented coyotes as the leading cause of mortality for neonates, and 1 study documented coyotes as a mortality factor for adult females. However, no study has used field-based vital rates to conduct sensitivity analyses or model deer population trajectories under potential harvest or predator removal strategies. We used low, medium, and high values of fawn survival, adult female survival, and fecundity data collected from Fort Bragg Military Installation, North Carolina to demonstrate the current declining population trajectory for deer (λ = 0.905; low λ = 0.788, high λ = 1.003). Consistent with other studies of ungulates, we determined adult female survival was the most sensitive and elastic vital rate. Further, for 3 potential management (“what if”) scenarios, we projected the population for 10 years using estimated vital rates. Reducing adult female harvest (λ = 0.935; low λ = 0.875, high λ = 1.002) and coyote removal (λ = 0.995; low λ = 0.898, high λ = 1.081) reduced the current population decline, whereas combining both approaches (λ = 1.024; low λ = 0.898, high λ = 1.141) resulted in population increases. Our data indicate that for low-density deer populations with heavy predation pressure on neonates, protecting adult females from harvest may not completely offset population declines. Coyote removal might be a necessary strategy because it could possibly increase very low fawn survival, which appears to be the most important vital rate influencing λ in our study. However, managers may have to start with reductions in adult female harvest because coyote removal would have to be continuous and consistently effective, making it an impractical management approach by itself. © 2015 The Wildlife Society.