Suchergebnisse

Basal metabolic rate (BMR) constitutes the lowest metabolic rate in a resting animal and is, therefore, considered to reflect the energetic cost of maintenance in endotherms. BMR is a reversible plastic trait that changes with environmental and ecological circumstances, albeit being heritable and susceptible to selection. Inter-individual variation within populations of small birds is substantial, and while many of the drivers of such variation have been identified, many remain unexplained. We studied winter BMR variation of juveniles over a 15-year period in a wild population of great tits Parus major at the northern border of their distribution. BMR during winter consistently changed between years, even after controlling for environmental factors, suggestive of a non-reversible developmental plasticity shaping the adult metabolic phenotype. BMR in cohorts of wintering great tits varied among winters as a response to minimum ambient temperatures experienced early in life, during the prehatching period. This developmental plasticity might be adaptive if temperatures experienced by growing embryos would metabolically prime them to an environment that they will likely encounter in future life. However, in line with a more unpredictable future climate, the risk of phenotype-environment mismatch is likely to lead to certain cohorts being poorly adapted to prevailing winter conditions, resulting in wider annual fluctuations in population size. ; Open access funding provided by Lund University. JB has been funded by the Andalucía Talent Hub Program launched by the Andalusian Knowledge Agency, co-funded by the European Union's Seventh Framework Program, Marie Skłodowska-Curie actions (COFUND—Grant Agreement no 291780) and the Ministry of Economy, Innovation, Science and Employment of the Junta de Andalucía. Supported by the Academy of Finland projects no. 102286 and 47195, and the Thule Institute of the University of Oulu (JB and EH) and by grants from the Swedish Research Council no. S-AA/F0 09677-311, B 650-19981108/2000, 629-2002-1893 and 621-2003-2912 (JÅN). ; Peer reviewed

Only one fifth of children aged 11–17 years are physically active for 60 min (min)/day. As physical activity (PA) levels track from childhood to adulthood, it is important to establish healthy PA behavior early in life. This study aims to evaluate whether daily school PA is associated with objectively measured PA independently of other socioecological factors. This study includes 209 children (120 boys) aged 9.8 ± 0.6 (mean ± SD) years from four government-funded schools in Sweden. One school including 113 children (70 boys) had 40 min of daily school PA (intervention) and three schools including 96 children (50 boys) had 60 min of school PA/week (control). PA was measured during four serial days with accelerometers. General PA (GPA) was defined as mean counts per minute (cpm). Socioecological factors were collected by questionnaires, and anthropometric traits by measurements. Analysis of covariance (ANCOVA) was used to test whether sex, age, relative age, body height, fat mass, lean mass, screen time activity, parental educational level, parental attitude towards PA, parental PA, sibling(s)' PA, living in a house or apartment, and whether the child was allocated to 40 min daily school PA or 60 min school PA/week, was independently associated with GPA. Daily GPA was found to be 686.9 ± 211.9 cpm. Independently of the other included factors, daily school PA was associated with +81.8 (15.7, 147.8) cpm compared with 60 min PA/week. This study infers that daily school PA is an appropriate strategy to promote PA in 10-year-old children, independently of different socioecological factors.

Only one fifth of children aged 11–17 years are physically active for 60 min (min)/day. As physical activity (PA) levels track from childhood to adulthood, it is important to establish healthy PA behavior early in life. This study aims to evaluate whether daily school PA is associated with objectively measured PA independently of other socioecological factors. This study includes 209 children (120 boys) aged 9.8 ± 0.6 (mean ± SD) years from four government-funded schools in Sweden. One school including 113 children (70 boys) had 40 min of daily school PA (intervention) and three schools including 96 children (50 boys) had 60 min of school PA/week (control). PA was measured during four serial days with accelerometers. General PA (GPA) was defined as mean counts per minute (cpm). Socioecological factors were collected by questionnaires, and anthropometric traits by measurements. Analysis of covariance (ANCOVA) was used to test whether sex, age, relative age, body height, fat mass, lean mass, screen time activity, parental educational level, parental attitude towards PA, parental PA, sibling(s)' PA, living in a house or apartment, and whether the child was allocated to 40 min daily school PA or 60 min school PA/week, was independently associated with GPA. Daily GPA was found to be 686.9 ± 211.9 cpm. Independently of the other included factors, daily school PA was associated with +81.8 (15.7, 147.8) cpm compared with 60 min PA/week. This study infers that daily school PA is an appropriate strategy to promote PA in 10-year-old children, independently of different socioecological factors.

Abstract
ContextUngulate prey can use increased vigilance to reduce their risk of predation, but little is known of the combined and interactive risk effects from humans and wolves in determining ungulate behaviour across time and space. Understanding the interplay between these risk effects is increasingly important, considering the recolonisation of several large carnivores to more human-dominated landscapes in Europe.
AimThe aim of the present study was to assess the vigilance behaviour expressed by red deer (Cervus elaphus) in response to both humans and wolves in the Polish Białowieża Forest.
MethodsUsing a camera-trap transect, the effect of distance to human settlements, hunting season, patterns of space use by wolves (Canis lupus), canopy openness, canopy height, time of day, as well as sex/age of individuals, on the vigilance behaviour observed in red deer was studied using a model-selection approach.
Key resultsWe did not find a clear effect of patterns of space use by wolves or distance to human settlements on red deer vigilance behaviour at the landscape scale. However, red deer showed increased vigilance during the hunting season and during the day outside of protected areas and reserves, because disturbance from human hunters is highest. Conversely, we also found that red deer were more vigilant at night within more protected areas, which is likely to be explained by the increased activity of wolves because human activity is strictly limited.
ConclusionsOur study showed that vigilance behaviour of red deer in Białowieża Primeval Forest is more driven by human hunting than by the frequency of wolf presence at a landscape scale. This could be explained by the higher temporal and spatial predictability of human hunting activities than wolf risk. We found that patterns of wolf space use, as opposed to the omnipresent fear effects from humans, had only localised effects by increasing vigilance levels during night hours in non-hunting areas of the forest. The reverse was observed outside of protected reserves. Understanding how prey species respond to this new combination of risk from natural predators and humans, is increasingly important in a landscape where human risk is becoming ever more potent and carnivores recolonise.