Improving the success of reinforcement programs: effects of a two-week confinement in a field enclosure on the anti-predator behaviour of captive-bred European hamsters.

Captive breeding programs are an important pillar in biodiversity conservation, aiming to prevent the extinction of threatened species. However, the establishment of self-sustaining populations in the wild through the release of captive-bred animals is often hampered by a high mortality upon release. In this study, we investigated how a 2-week confinement period within a large field enclosure affected the anti-predator behaviour of 'naive' captive-bred hamsters and how potential modifications persisted over time.

Telomere length positively correlates with pace-of-life in a sex- and cohort-specific way and elongates with age in a wild mammal.

Understanding ageing and the diversity of life histories is a cornerstone in biology. Telomeres, the protecting caps of chromosomes, are thought to be involved in ageing, cancer risks and life-history strategies. They shorten with cell division and age in somatic tissues of most species, possibly limiting lifespan.

What is the impact on work of osteoporotic fractures in active patients? A retrospective fracture-liaison-service study-Optiwork 1.

Purpose: Osteoporotic fractures have economic consequences and can alter the quality of life. Nevertheless, the direct impact on work has been infrequently reported. Our objective was to estimate the proportion of working patients resuming paid employment within the 3 months following an osteoporotic fracture, and to assess the consequences on their productivity and quality of life.

Territorial scent-marking effects on vigilance behavior, space use, and stress in female Columbian ground squirrels.

Social environments can profoundly affect the behavior and stress physiology of group-living animals. In many territorial species, territory owners advertise territorial boundaries to conspecifics by scent marking. Several studies have investigated the information that scent marks convey about donors' characteristics (e.

Integrating Mortality Risk and the Adaptiveness of Hibernation.

Low mortality rate is often associated with slow life history, and so far, has mainly been assessed through examinations of specific adaptations and lifestyles that limit mortality risk. However, the organization of activity time budgets also needs to be considered, since some activities and the time afforded for performing them may expose animals to higher mortality risks such as increased predation and/or increased metabolic stress. We examined the extent of activity time budgets contribution to explaining variation in life history traits in mammals.

Consumption of red maple in anticipation of beech mast-seeding drives reproduction in eastern chipmunks.

Understanding the determinants of reproduction is a central question in evolutionary ecology. In pulsed-resource environments, the reproduction and population dynamics of seed consumers are driven by pulsed production of seeds by trees or mast-seeding. In Southern Québec, eastern chipmunks Tamias striatus exclusively reproduce during the summer before and the spring after a mast-seeding event of American beech.

Captive-reared European hamsters follow an offensive strategy during risk-assessment.

Understanding whether captive-reared animals destined to reintroduction are still able to discriminate predators has important implications for conservation biology. The endangered European hamster benefits from conservation programs throughout Europe, in which several thousand individuals are released into the wild every year. Despite this, the anti-predator strategy of hamsters and their ability to maintain predator discrimination in captivity remain to be investigated.

A focus on the European hamster to illustrate how to monitor endangered species.

Agriculture intensification, marked by the generalization of crop monoculture, by the increase in plot size and by the reduction of plant diversity, has led to huge decline in wildlife in European farmlands. In such habitat, research has long been biased towards birds and invertebrates, while very few studies have investigated the effect on small mammals. Considering the European hamster, Cricetus cricetus, we therefore review the different techniques that can be used to investigate the impact of environmental changes and conservation measures in small and endangered wild mammals.

Dietary proteins improve hibernation and subsequent reproduction in the European hamster, Cricetus cricetus.

The reproductive success of hibernators depends not only on food quality during reproduction but also on their body condition when emerging after hibernation, which, in turn, is highly dependent on the hibernation pattern. To date, no studies, to our knowledge, have fully investigated the role of macronutrients throughout the annual lifecycle of hibernators and the strong interdependency between its different phases. This study tested the effects of two diets with different lipid and protein composition on the prehibernation body condition, hibernation pattern, and reproduction of captive-reared European hamsters.

Monocultural sowing in mesocosms decreases the species richness of weeds and invertebrates and critically reduces the fitness of the endangered European hamster.

Intensive cereal monoculture is currently the main cause of biodiversity decline in Europe. However, it is difficult to disentangle the effects of intensive monoculture (e.g.

Diets derived from maize monoculture cause maternal infanticides in the endangered European hamster due to a vitamin B3 deficiency.

From 1735 to 1940, maize-based diets led to the death of hundreds of thousands of people from pellagra, a complex disease caused by tryptophan and vitamin B3 deficiencies. The current cereal monoculture trend restricts farmland animals to similarly monotonous diets. However, few studies have distinguished the effects of crop nutritional properties on the reproduction of these species from those of other detrimental factors such as pesticide toxicity or agricultural ploughing.

How maize monoculture and increasing winter rainfall have brought the hibernating European hamster to the verge of extinction.

Over the last decades, climate change and agricultural intensification have been identified as two major phenomena negatively affecting biodiversity. However, little is known about their effects on the life-history traits of hibernating species living in agro-ecosystems. The European hamster (Cricetus cricetus), once a common rodent on agricultural land, is now on the verge of extinction in France.

Maternal effects underlie ageing costs of growth in the zebra finch (Taeniopygia guttata).

Maternal effects provide a mechanism to adapt offspring phenotype and optimize the mother's fitness to current environmental conditions. Transferring steroids to the yolk is one way mothers can translate environmental information into potential adaptive signals for offspring. However, maternally-derived hormones might also have adverse effects for offspring.