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Dandy N.,Center for Human and Ecological science | Van Der Wal R.,University of Aberdeen
Landscape and Urban Planning | Year: 2011

Woodlands and forests perform multiple functions for contemporary society. Their management affects, and is affected by, numerous stakeholders each of which relate to and appreciate woodlands in distinct ways. Capturing these stakeholder preferences for inclusion within increasingly collaborative planning and management processes is recognised as an important task. This paper describes and analyses an innovative, strongly qualitative method (field-based interactive photo-elicitation) via which to achieve this. Small groups of research participants were taken to visit, and thus experience, three predominantly oak woodlands in the UK, representing different levels of deer browsing. The impact of large herbivores is strongly related to the functions that woodlands can perform, but their management can be particularly contentious and thus perhaps a key challenge to stakeholder collaboration. The participants' were encouraged to record this experience through taking photographs, and making notes. These photographs and notes formed the stimulus for group discussion, immediately following the field visits. Data analysis followed an inductive ('grounded') approach and identified seven key themes in the participants reported preferences for woodland landscapes. We conclude that the method advances the field of landscape preference assessment and can capture stakeholder preferences in a rich and cost-effective manner. The research identified substantial shared appreciation of woodland landscapes across 'professional' and 'lay' social groups, challenging several previous studies. © 2011. Source


Millon A.,University of Aberdeen | Millon A.,Aix - Marseille University | Petty S.J.,University of Aberdeen | Petty S.J.,Center for Human and Ecological science | And 2 more authors.
Journal of Animal Ecology | Year: 2011

Natal conditions and senescence are two major factors shaping life-history traits of wild animals. However, such factors have rarely been investigated together, and it remains largely unknown whether they interact to affect age-specific performance. We used 27years of longitudinal data collected on tawny owls with estimates of prey density (field voles) from Kielder Forest (UK) to investigate how prey density at birth affects ageing patterns in reproduction and survival. Natal conditions experienced by tawny owls, measured in terms of vole density, dramatically varied among cohorts and explained 87% of the deviance in first-year apparent survival (annual estimates ranging from 0·07 to 0·33). We found evidence for senescence in survival for females as well as for males. Model-averaged estimates showed that adult survival probability declined linearly with age for females from age1. In contrast, male survival probability, lower on average than for female, declined after a plateau at age1-3. We also found evidence for reproductive senescence (number of offspring). For females, reproductive performance increased until age9 then declined. Males showed an earlier decline in reproductive performance with an onset of senescence at age3. Long-lasting effects of natal environmental conditions were sex specific. Female reproductive performance was substantially related to natal conditions (difference of 0·24 fledgling per breeding event between females born in the first or third quartile of vole density), whereas male performance was not. We found no evidence for tawny owls born in years with low prey density having accelerated rates of senescence. Our results, combined with previous findings, suggest the way natal environmental conditions affect senescence varies not only across species but also within species according to gender and the demographic trait considered. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society. Source


O'Brien L.,Center for Human and Ecological science | Varley P.,University College West
Perspectives in Public Health | Year: 2012

Aims: This paper discusses the use of ethnographic approaches to explore how engagement with natural landscapes might benefit people's health. Methods: Drawing on a selected review of empirical research we identified 30 relevant research papers that utilised qualitative methods to explore health issues and engagement with nature. Three examples of 'alternative' - i.e. non-mainstream qualitative approaches - are used to illustrate how different methods can be used to explore people's experiences of engaging with nature for health. Results: While quantitative methods are dominant in health research, qualitative approaches are becoming more widely used. Approaches such as autoethnography can add value to nature and health studies by providing opportunities for researchers to be self-critical of their role as a researcher. Accompanied visits and visual ethnography can afford the researcher rich data about bodily movement, facial expressions and journeys, as well as dialogues associated with the meanings of nature for health. Conclusions: The paper concludes by suggesting that ethnographic methods can provide useful and important insights into why people engage with the natural environment and the range of health benefits they may gain from contact with nature. Copyright © 2012 Royal Society for Public Health. Source


Millon A.,CNRS Mediterranean Institute for Biodiversity and Ecology Marine and Continental | Millon A.,University of Aberdeen | Petty S.J.,University of Aberdeen | Petty S.J.,Center for Human and Ecological science | And 4 more authors.
Global Change Biology | Year: 2014

Predicting the dynamics of animal populations with different life histories requires careful understanding of demographic responses to multifaceted aspects of global changes, such as climate and trophic interactions. Continent-scale dampening of vole population cycles, keystone herbivores in many ecosystems, has been recently documented across Europe. However, its impact on guilds of vole-eating predators remains unknown. To quantify this impact, we used a 27-year study of an avian predator (tawny owl) and its main prey (field vole) collected in Kielder Forest (UK) where vole dynamics shifted from a high- to a low-amplitude fluctuation regime in the mid-1990s. We measured the functional responses of four demographic rates to changes in prey dynamics and winter climate, characterized by wintertime North Atlantic Oscillation (wNAO). First-year and adult survival were positively affected by vole density in autumn but relatively insensitive to wNAO. The probability of breeding and number of fledglings were higher in years with high spring vole densities and negative wNAO (i.e. colder and drier winters). These functional responses were incorporated into a stochastic population model. The size of the predator population was projected under scenarios combining prey dynamics and winter climate to test whether climate buffers or alternatively magnifies the impact of changes in prey dynamics. We found the observed dampening vole cycles, characterized by low spring densities, drastically reduced the breeding probability of predators. Our results illustrate that (i) change in trophic interactions can override direct climate change effect; and (ii) the demographic resilience entailed by longevity and the occurrence of a floater stage may be insufficient to buffer hypothesized environmental changes. Ultimately, dampened prey cycles would drive our owl local population towards extinction, with winter climate regimes only altering persistence time. These results suggest that other vole-eating predators are likely to be threatened by dampening vole cycles throughout Europe. © 2014 The Authors. Global Change Biology Published by John Wiley & Sons Ltd. Source


Millon A.,University of Aberdeen | Petty S.J.,University of Aberdeen | Petty S.J.,Center for Human and Ecological science | Lambin X.,University of Aberdeen
Journal of Animal Ecology | Year: 2010

1. According to life-history theory, environmental variability and costs of reproduction account for the prevalence of delayed reproduction in many taxa. Empirical estimates of the fitness consequences of different ages at first breeding in a variable environment are few however such that the contributions of environmental and individual variability remains poorly known. 2. Our objectives were to elucidate processes that underpin variation in delayed reproduction and to assess lifetime consequences of the age of first breeding in a site-faithful predator, the tawny owl Strix aluco L. subjected to fluctuating selection linked to cyclical variation in vole density (typically 3-year cycles with low, increasing and decreasing vole densities in successive years). 3. Amultistate capture-recapture model revealed that owl cohorts had strikingly different juvenile survival prospects, with estimates ranging from 0·08 to 0·33 respectively for birds born in Decrease and Increase phases of the vole cycle. This resulted in a highly skewed population structure with >75% of local recruits being reared during Increase years. In contrast, adult survival remained constant throughout a vole cycle. The probability of commencing reproduction was lower at age 1 than at older ages, and especially so for females. From age 2 onwards, pre-breeders had high probabilities of entering the breeding population. 4. Variation in lifetime reproductive success was driven by the phase of the vole cycle in which female owls started their breeding career (26-47% of variance explained, whether based on the number of local recruits or fledglings), more than by age at first breeding or by conditions experienced at birth. Females who postponed reproduction to breed for the first time at age 3 during an Increase phase, produced more recruits, even when accounting for birds that may have died before reproduction. No such effects were detected for males. 5. Sex-specific costs of early reproduction may have accounted for females being more prone to delay reproduction. Contrary to expectations from a best-of-a-bad job strategy, early-hatched, hence potentially higher-quality females were more likely to breed at age 1, but then experienced rapidly declining food resources and so seemed caught in a life-history trap set by the multiannual vole cycle. ©2009 The Authors. Journal compilation ©2009 British Ecological Society. Source

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