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1.
PLoS One ; 18(10): e0293062, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37856492

RESUMO

Respiratory disease is responsible for dramatic population declines in bighorn sheep (Ovis canadensis), and respiratory pathogen diagnostics contribute to the management of bighorn populations. To create a comprehensive and consistent approach to bighorn sheep respiratory diagnostics, we created a culture-independent assay to detect and strain type Mannheimia haemolytica, Bibersteinia trehalosi, Pasteurella multocida, and Mycoplasma ovipneumoniae. The assay also detects and characterizes the Pasteurellaceae leukotoxin A gene, and broadly assesses the bacterial composition of each sample based on 16S rRNA sequences. The assay is based on a three-step approach: 1) Multiplex PCR to amplify targets including eight loci for each bacterial species, the Pasteurellaceae lktA gene, and the 16S rRNA gene 2) Library preparation, barcoding, and short-read Illumina sequencing to determine the genetic sequences of each target, and 3) Bioinformatics in the form of automated software to analyze genetic sequences. The assay was designed to assess shared pathogens between domestic and bighorn sheep, but could be useful for many applications in bighorn sheep respiratory disease research and management.


Assuntos
Mannheimia haemolytica , Doenças Respiratórias , Doenças dos Ovinos , Carneiro da Montanha , Animais , Ovinos , Carneiro da Montanha/genética , Carneiro da Montanha/microbiologia , Carneiro Doméstico , Reação em Cadeia da Polimerase Multiplex , RNA Ribossômico 16S/genética , Doenças dos Ovinos/epidemiologia , Mannheimia haemolytica/genética , Biologia Computacional
2.
Ecol Evol ; 9(18): 10415-10431, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31632646

RESUMO

As human populations continue to expand across the world, the need to understand and manage wildlife populations within the wildland-urban interface is becoming commonplace. This is especially true for large carnivores as these species are not always tolerated by the public and can pose a risk to human safety. Unfortunately, information on wildlife species within the wildland-urban interface is sparse, and knowledge from wildland ecosystems does not always translate well to human-dominated systems. Across western North America, cougars (Puma concolor) are routinely utilizing wildland-urban habitats while human use of these areas for homes and recreation is increasing. From 2007 to 2015, we studied cougar resource selection, human-cougar interaction, and cougar conflict management within the wildland-urban landscape of the northern Front Range in Colorado, USA. Resource selection of cougars within this landscape was typical of cougars in more remote settings but cougar interactions with humans tended to occur in locations cougars typically selected against, especially those in proximity to human structures. Within higher housing density areas, 83% of cougar use occurred at night, suggesting cougars generally avoided human activity by partitioning time. Only 24% of monitored cougars were reported for some type of conflict behavior but 39% of cougars sampled during feeding site investigations of GPS collar data were found to consume domestic prey items. Aversive conditioning was difficult to implement and generally ineffective for altering cougar behaviors but was thought to potentially have long-term benefits of reinforcing fear of humans in cougars within human-dominated areas experiencing little cougar hunting pressure. Cougars are able to exploit wildland-urban landscapes effectively, and conflict is relatively uncommon compared with the proportion of cougar use. Individual characteristics and behaviors of cougars within these areas are highly varied; therefore, conflict management is unique to each situation and should target individual behaviors. The ability of individual cougars to learn to exploit these environments with minimal human-cougar interactions suggests that maintaining older age structures, especially females, and providing a matrix of habitats, including large connected open-space areas, would be beneficial to cougars and effectively reduce the potential for conflict.

3.
J Anim Ecol ; 87(3): 609-622, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29380374

RESUMO

Conflicts between large mammalian predators and humans present a challenge to conservation efforts, as these events drive human attitudes and policies concerning predator species. Unfortunately, generalities portrayed in many empirical carnivore landscape selection studies do not provide an explanation for a predator's occasional use of residential development preceding a carnivore-human conflict event. In some cases, predators may perceive residential development as a risk-reward trade-off. We examine whether state-dependent mortality risk-sensitive foraging can explain an apex carnivore's (Puma concolor) occasional utilization of residential areas. We assess whether puma balance the risk and rewards in a system characterized by a gradient of housing densities ranging from wildland to suburban. Puma GPS location data, characterized as hunting and feeding locations, were used to assess landscape variables governing hunting success and hunting site selection. Hunting site selection behaviour was then analysed conditional on indicators of hunger state. Residential development provided a high energetic reward to puma based on increases in prey availability and hunting success rates associated with increased housing density. Despite a higher energetic reward, hunting site selection analysis indicated that pumas generally avoided residential development, a landscape type attributed with higher puma mortality risk. However, when a puma experienced periods of extended hunger, risk avoidance behaviour towards housing waned. This study demonstrates that an apex carnivore faces a trade-off between acquiring energetic rewards and avoiding risks associated with human housing. Periods of hunger can help explain an apex predator's occasional use of developed landscapes and thus the rare conflicts in the wildland-urban interface. Apex carnivore movement behaviours in relation to human conflicts are best understood as a three-player community-level interaction incorporating wild prey distribution.


Assuntos
Aprendizagem da Esquiva , Fome , Puma/fisiologia , Animais , Colorado , Feminino , Masculino , Comportamento Predatório , Assunção de Riscos
4.
PLoS One ; 10(9): e0138915, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26398546

RESUMO

Animal space use studies using GPS collar technology are increasingly incorporating behavior based analysis of spatio-temporal data in order to expand inferences of resource use. GPS location cluster analysis is one such technique applied to large carnivores to identify the timing and location of feeding events. For logistical and financial reasons, researchers often implement predictive models for identifying these events. We present two separate improvements for predictive models that future practitioners can implement. Thus far, feeding prediction models have incorporated a small range of covariates, usually limited to spatio-temporal characteristics of the GPS data. Using GPS collared cougar (Puma concolor) we include activity sensor data as an additional covariate to increase prediction performance of feeding presence/absence. Integral to the predictive modeling of feeding events is a ground-truthing component, in which GPS location clusters are visited by human observers to confirm the presence or absence of feeding remains. Failing to account for sources of ground-truthing false-absences can bias the number of predicted feeding events to be low. Thus we account for some ground-truthing error sources directly in the model with covariates and when applying model predictions. Accounting for these errors resulted in a 10% increase in the number of clusters predicted to be feeding events. Using a double-observer design, we show that the ground-truthing false-absence rate is relatively low (4%) using a search delay of 2-60 days. Overall, we provide two separate improvements to the GPS cluster analysis techniques that can be expanded upon and implemented in future studies interested in identifying feeding behaviors of large carnivores.


Assuntos
Carnivoridade , Distribuição Animal , Animais , Análise por Conglomerados , Feminino , Sistemas de Informação Geográfica , Masculino , Puma , Melhoria de Qualidade
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