18 research outputs found

    Do Multi-Paddock Systems Increase Evenness of Grazing at the Paddock Scale?

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    There is ongoing debate about the benefits of multi-paddock rotationally grazed systems compared to continuous grazing (Briske et al. 2008). One of the purported benefits of high density short duration grazing is more spatially uniform defoliation. A commercial-scale trial in northern Australia (Hunt et al. 2013) compared continuously grazed paddocks to cell grazed and wet season spelled systems in newly developed paddocks. This paper reports the effect of grazing system on defoliation with distance to water through time

    Estimated age at death for owl ring recoveries, and recruitment of breeders into the owl population

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    Data were collected in the field using methods described in the manuscript. No abbreviations used

    Data from: Age and sex-selective predation as moderators of the overall impact of predation

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    Currently, there is no general agreement about the extent to which predatorsā€™ impact prey population dynamics, as it is often poorly predicted by predation rates and species abundances. This could in part be caused by variation in the type of selective predation occurring. Notably, if predation is selective on categories of individuals that contribute little to future generations, it may moderate the impact of predation on prey population dynamics. However, despite its prevalence, selective predation has seldom been studied in this context. Using recoveries of ringed tawny owls (Strix aluco) predated by ā€˜superpredatorsā€™, northern goshawks (Accipiter gentilis) as they colonised the area, we investigated the extent to which predation was sex and age-selective. Predation of juvenile owls was disproportionately high. Amongst adults, predation was strongly biased towards females and predation risk appeared to increase with age. This implies age-selective predation may shape the decline in survival with age, observed in tawny owls. To determine whether selective predation can modulate the overall impact of predation, age-based population matrix models were used to simulate the overall impact of five different patterns of age-selective predation, including the pattern actually observed in the study site. The impact on owl population size varied by up to 50%, depending on the pattern of selective predation. The simulation of the observed pattern of predation had a relatively small impact on population size, close to the least harmful scenario, predation on juveniles only. The actual changes in owl population size and structure, observed during goshawk colonisation were also analysed. Owl population size and immigration were unrelated to goshawk abundance. However, goshawk abundance appeared to interact with owl food availability to have a delayed effect on recruitment into the population. This study provides strong evidence to suggest that predation of other predators is both age and sex-selective and that selective predation of individuals with a low reproductive value may mitigate the overall impact of predators on prey population dynamics. Consequently, our results highlight how accounting for the type of selective predation occurring is likely to improve future predictions of the overall impact of predation

    Self-Concept, Product Involvement, and Responses to Self-Congruent Advertising

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    This study examines the influence of self-congruity and product involvement on advertising responses. In addition to three traditional advertising responses, attitude-toward-the-ad, brand interest, and purchase intention, this study also examines participants\u27 affective responses (arousal and valence) and their relationships with other advertising responses. The results indicated that while a higher degree of product involvement generated more positive responses toward the product information, within the same product category participants reported more positive emotional responses, more positive attitude-toward-the-ad, stronger brand interest, and stronger purchase intention toward self-congruent brands. Valence and arousal were found to be significantly correlated with attitude-toward-the-ad, brand interest, and purchase intention
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