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Browsing by Author "Conner, L. Mike"

Now showing 1 - 4 of 4
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    Balancing carnivore conservation and sustainable hunting of a key prey species: A case study on the Florida panther and white-tailed deer
    Bled, Florent; Cherry, Michael J.; Garrison, Elina P.; Miller, Karl, V; Conner, L. Mike; Abernathy, Heather N.; Ellsworth, W. Hunter; Margenau, Lydia L. S.; Crawford, Daniel A.; Engebretsen, Kristin N.; Kelly, Brian D.; Shindle, David B.; Chandler, Richard B. (Wiley, 2022-08)
    Large carnivore restoration programs are often promoted as capable of providing ecosystem services. However, these programs rarely measure effects of successful restoration on other economically and ecologically important species. In South Florida, while the endangered Florida panther Puma concolor coryi population has increased in recent years due to conservation efforts, the population of its main prey, the white-tailed deer Odocoileus virginianus, has declined in some regions. The extent to which panther predation has affected deer populations has been difficult to assess because several other factors have changed during this period, including hydrology and hunting regulations. We collected known-fate survival data on 241 GPS-collared adult deer (156 females and 85 males) from 2015 to 2018 in the Florida Panther National Wildlife Refuge and the Big Cypress National Preserve in Florida, USA, to assess effects of panther predation on the deer population, while also evaluating the impacts of hunting and hydrology. Predation was the primary cause of death (110 of 134 mortalities), and 87% of predation events were attributed to panthers, a much greater rate than reported by studies conducted before the panther genetic restoration effort initiated in 1995. One deer was legally harvested, and two were likely killed by poachers. Increasing water depth decreased female survival but had little impact on male survival, and drowning was never a cause of mortality. Females had greater survival probability than males, except during fawning season. From 2015 to 2018, annual survival rates increased from 0.61 (0.52-0.70) to 0.86 (0.79-0.91) for females, and from 0.45 (95% CI: 0.33-0.58) to 0.79 (0.69-0.86) for males. Synthesis and applications. High predation rates, coupled with previous evidence of low recruitment of deer in South Florida, suggest that it will be challenging to meet society's competing demands for large predator restoration and sustainable deer harvest. Deer hunting in the area must remain tightly controlled, for now, if it is to be sustainable, and managers should seek to mitigate effects of high waters and improve deer habitat quality to increase deer population viability. Future work should closely monitor the deer population to assess if management actions can increase vital rates and abundance in the context of high predation rates.
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    Behavioral response of white-tailed deer to coyote predation risk
    Gulsby, William D.; Cherry, Michael J.; Johnson, James T.; Conner, L. Mike; Miller, Karl V. (Ecological Society of America, 2018-03)
    Behavioral responses of prey to predation risk can affect lower trophic levels. White-tailed deer (Odocoileus virginianus; hereafter deer) increase vigilance in response to coyote (Canis latrans) presence, but vigilance responses to spatiotemporal variation in coyote abundance are unknown. Therefore, we examined the relationship between deer foraging behavior and coyote abundance on two 2000-ha study areas in Georgia, USA, during 2010-2013. We used baited camera traps during fall and winter to quantify deer behavior (i.e., feeding or vigilant) and estimated coyote abundance using fecal genotyping to noninvasively mark and recapture individuals. During 2011 and 2012, coyote removals were implemented on each study area. Coyote abundance (i.e., predation risk) varied spatiotemporally and was a predictor of foraging behavior during at least one season for all sex-age classes of deer except juveniles. Adult males were more sensitive to predation risk in winter, after the breeding season, whereas adult females were sensitive to predation risk during both seasons, but more so during fall when offspring are at greater risk. Yearling males were more sensitive to predation risk than adult males, and juveniles were least sensitive to predation risk, likely because of inexperience and high energetic demands. Reproductive chronology explained sex-specific and seasonal antipredator responses to predation risk, but there was a non-linear relationship between indirect predator effects and direct predation risk for some sex-age classes. Our results suggest deer detect and respond behaviorally to variation in coyote abundance. Due to the widespread distribution of deer and their interactions at multiple trophic levels, the ecological implications of this finding may be wide-reaching.
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    Fire-mediated foraging trade-offs in white-tailed deer
    Cherry, Michael J.; Warren, Robert J.; Conner, L. Mike (Wiley, 2017-03-14)
    Predation risk can induce individual prey to express behavioral, physiological, and morphological traits that can influence population-level processes. Maternal care is an intuitive link between predator-mediated traits of individuals and population-level processes because maternal investment can decrease with predation risk, and often influences processes such as neonatal growth, survival, and recruitment. During fawn-rearing, many ungulate species restrict space use to a fraction of their home range. Selection of and within these areas can influence the quality of concealment cover for fawns and forage availability during early lactation which is the peak of maternal investment. Fire influences the distribution of food resources and cover for prey and their predators. In frequently burned systems, ungulates typically move into recently burned areas to exploit increased forage quality and detection of predators that use cover to stalk their prey. We investigated the effects of time since fire on the selection of and within fawnrearing areas and foraging behavior in white-tailed deer in a frequently burned pine savanna. White-tailed deer selected woodlands with greater time since fire and avoided recently burned areas, likely sacrificing forage quality for concealment cover during fawn-rearing. We then used camera data to test the effects of time since fire on foraging behavior and found that with increased time since fire female white-tailed deer are more likely to be feeding while foraging at concentrated resources of standardized quality and quantity. By combining these data, we revealed that the counterintuitive avoidance of high-quality forage in recently burned areas can be explained by predation risk. We documented fire effects on proactive (i.e., avoidance of recent burns) and reactive (decreased vigilance with increasing time since fire) antipredator behaviors in white-tailed deer during the fawning season. Our results suggest that fire can spatially and temporally alter a landscape causing dynamic predation risk to which prey must respond to maximize fitness.
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    Habitat selection and diurnal refugia of gray foxes in southwestern Georgia, USA
    Deuel, Nicholas R.; Conner, L. Mike; Miller, Karl V.; Chamberlain, Michael J.; Cherry, Michael J.; Tannenbaum, Larry V. (PLOS, 2017-10-17)
    Understanding habitat selection of gray foxes (Urocyon cinereoargenteus) is essential to evaluate their potential response to changes in land use and predator communities. Few studies have evaluated temporal habitat selection or explicitly identified habitats used by gray foxes for diurnal refugia. We used GPS collars to obtain location data for 34 gray foxes (20 males and 14 females) from February 2014 to December 2015 to evaluate temporal (seasonal and diel) habitat selection and selection of diurnal refugia in southwestern Georgia, USA. We analyzed habitat selection at 2 levels, selection of a core area within the home range and selection of locations within the home range. Habitat selection was non-random (P < 0.001) but consistent among seasons, between day and night, and between sexes (P > 0.05). Hardwoods, human use (i.e., areas associated with regular human activity such as buildings, lawns, parking areas, etc.), and roads were selected (P < 0.05), whereas pine dominated stands were used randomly (P > 0.05). Selection of habitats for diurnal refugia did not vary seasonally or by sex (P > 0.05), with foxes selecting (P < 0.05) areas near hardwood forests, roads, agriculture, human use, pastures/food plots, and shrub scrub habitats. Gray foxes were observed on the ground while resting, and we found no evidence of gray foxes diurnally resting in trees. Our results suggest that on our study area, gray foxes are an edge species that prefer forests with a hardwood component in areas near human use and roads.