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3.
Oecologia ; 198(1): 91-98, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34981219

RESUMO

Fear of the human 'super predator' has been demonstrated to so alter the feeding behavior of large carnivores as to cause trophic cascades. It has yet to be experimentally tested if fear of humans has comparably large effects on the feeding behavior of large herbivores. We conducted a predator playback experiment exposing white-tailed deer to the vocalizations of humans, extant or locally extirpated non-human predators (coyotes, cougars, dogs, wolves), or non-predator controls (birds), at supplemental food patches to measure the relative impacts on deer feeding behavior. Deer were more than twice as likely to flee upon hearing humans than other predators, and hearing humans was matched only by hearing wolves in reducing overall feeding time gaged by visits to the food patch in the following hour. Combined with previous, site-specific research linking deer fecundity to predator abundance, this study reveals that fear of humans has the potential to induce a larger effect on ungulate reproduction than has ever been reported. By demonstrating that deer most fear the human 'super predator', our results point to the fear humans induce in large ungulates having population- and community-level impacts comparable to those caused by the fear humans induce in large carnivores.


Assuntos
Carnívoros , Cervos , Lobos , Animais , Cães , Cadeia Alimentar , Herbivoria , Humanos , Comportamento Predatório
4.
Ecology ; 103(10): e3583, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34767254

RESUMO

Studies of animal abundance and distribution are often conducted independently of research on movement, despite the important links between processes. Movement can cause rapid changes in spatial variation in density, and movement influences detection probability and therefore estimates of abundance from inferential methods such as spatial capture-recapture (SCR). Technological developments including camera traps and GPS telemetry have opened new opportunities for studying animal demography and movement, yet statistical models for these two data types have largely developed along parallel tracks. We present a hierarchical model in which both datasets are conditioned on a movement process for a clearly defined population. We fitted the model to data from 60 camera traps and 23,572 GPS telemetry locations collected on 17 male white-tailed deer in the Big Cypress National Preserve, Florida, USA during July 2015. Telemetry data were collected on a 3-4 h acquisition schedule, and we modeled the movement paths of all individuals in the region with a Ornstein-Uhlenbeck process that included individual-specific random effects. Two of the 17 deer with GPS collars were detected on cameras. An additional 20 male deer without collars were detected on cameras and individually identified based on their unique antler characteristics. Abundance was 126 (95% CI: 88-177) in the 228 km2 region, only slightly higher than estimated using a standard SCR model: 119 (84-168). The standard SCR model, however, was unable to describe individual heterogeneity in movement rates and space use as revealed by the joint model. Joint modeling allowed the telemetry data to inform the movement model and the SCR encounter model, while leveraging information in the camera data to inform abundance, distribution and movement. Unlike most existing methods for population-level inference on movement, the joint SCR-movement model can yield unbiased inferences even if non-uniform sampling is used to deploy transmitters. Potential extensions of the model include the addition of resource selection parameters, and relaxation of the closure assumption when interest lies in survival and recruitment. These developments would contribute to the emerging holistic framework for the study of animal ecology, one that uses modern technology and spatio-temporal statistics to learn about interactions between behavior and demography.


Assuntos
Cervos , Animais , Ecologia/métodos , Masculino , Modelos Estatísticos , Movimento , Telemetria/veterinária
5.
Ecol Evol ; 9(6): 3264-3275, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30962891

RESUMO

Fear of predators can behaviorally mediate prey population dynamics, particularly when predation risk influences reproductive investment. However, the costs of reproductive investment may mitigate predation risk aversion relative to periods when the link between reproductive output and prey behavior is weaker.We posit that intensity of reproductive investment in ungulates may predict their response to predation risk such that the sexes increase risk exposure during biological seasons that are pivotal to reproductive success, such as the fawn-rearing and breeding seasons for females and males, respectively.We examined the activity patterns of sympatric white-tailed deer (Odocoileus virginianus), a sexually segregated polygynous ungulate, and Florida panthers (Puma concolor coryi) in the context of the "risky times - risky places hypothesis" and the reproductive strategy hypothesis. We compared detection rates and diel activity overlap of both species using motion-triggered camera traps positioned on (n = 120) and off (n = 60) anthropogenic trails across five reproductive seasons.Florida panthers were nocturnal and primarily observed on-trail providing an experimental framework with risky times and risky places. Contrary to studies in other taxa inversely correlating prey reproductive investment to predation risk, the sexes of deer were more risk prone during sex-specific seasons associated with intense reproductive investment.Our results suggest spatiotemporally variable predation risk influences sex-specific behavioral decision-making in deer such that reproductive success is maximized.

6.
Vasc Endovascular Surg ; 52(8): 669-673, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30058451

RESUMO

Patent foramen ovale (PFO) is a common heart condition in adults. Closure with a septal occluder device is a safe, well-established treatment option with excellent clinical outcomes. One rare complication of percutaneous PFO closure is embolization of the device to the heart chambers or distal vasculature. Most device migrations are recognized during or shortly after implantation. While many endovascular retrievals of migrated devices are successful, there are still a high percentage of surgical interventions performed. We report a case of a septal occluder device that embolized to the abdominal aorta and was discovered 7 days after implantation. Endovascular techniques with a snare and endobronchial forceps were used to retrieve the device safely.


Assuntos
Aorta Abdominal , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Remoção de Dispositivo/métodos , Procedimentos Endovasculares , Forame Oval Patente/terapia , Migração de Corpo Estranho/terapia , Dispositivo para Oclusão Septal/efeitos adversos , Adulto , Aorta Abdominal/diagnóstico por imagem , Aortografia/métodos , Angiografia por Tomografia Computadorizada , Migração de Corpo Estranho/diagnóstico por imagem , Humanos , Masculino , Resultado do Tratamento
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