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We quantified the repeatability of .900 individual measures of hind foot length from 2 French populations of roe deer (Capreolus capreolus) monitored by capture-recapture. We found a high repeatability (i.e., high intra-class correlation, 0.76, 95% CI = 0.72- 0.83 and 0.92, 95% CI = 0.91-0.95) in both populations. We also found that inexperienced observers reached a high level of intra- (1.00, 95% CI = 0.96-1.00) and inter-observer repeatability (0.99, 95% CI = 0.98-1.00) when measuring hind foot length of harvested animals with a tool specifically designed for this task. Managers should pay particular attention to limit measurement errors because unreliable measurements require an increased sample size to assess individual variation and can mask biological patterns. [ABSTRACT FROM AUTHOR]

1. Environmental conditions shape population growth through their impact on demographic parameters. While knowledge has accumulated concerning the effects of population density and climatic conditions, a topical question now concerns how predation and harvest influence demographic parameters and population growth (λ). 2. We performed a comparative demographic analysis based on projection matrix models for female roe deer. Population-specific matrices were parameterized based on longitudinal data from five intensively monitored populations in Norway and France, spanning a large variability in environmental characteristics such as densities of large predators, hunter harvest and seasonality. 3. As expected for a large iteroparous vertebrate, temporal variation was invariably higher in recruitment than in adult survival, and the elasticity of adult survival was consistently higher than that of recruitment. However, the relative difference in elasticity of λ to recruitment and adult survival varied strongly across populations, and was closely correlated with adult survival. 4. Different traits accounted for most of the variance in λ in different ecological settings. Adult survival generally contributed more in populations with low mean adult survival and low mean growth rate during the study period. Hunters and predators (Eurasian lynx and red foxes) occurred in two of our study populations and contributed substantially to the variance in λ, accounting for a total of 35% and 70% in the two populations respectively. 5. Across populations, we did not find any evidence that roe deer increased their reproductive output when faced with harsh conditions, resulting in some populations having negative growth rates. 6. Generation time, a measure of the speed of the life-history cycle, increased from less than 4 years in the most productive population (‘roe deer heaven’) to more than 6 years in declining populations facing predation from lynx, red fox and hunters (‘roe deer hell’), and was tightly and inversely correlated with λ. Such a deceleration of the life cycle in declining populations might be a general feature in large herbivores. 7. Our results shows that the plethora of environmental conditions faced by populations of large herbivores also induce high intraspecific variation in their ranking along the ‘fast–slow’ continuum of life-history tactics. [ABSTRACT FROM AUTHOR]

We tested the influence of population density and of drought intensity (measured as the Gaussen Index in spring and summer of the year of birth) on winter body mass, hind foot length, and body condition of roe deer fawns. Body mass decreased with increasing density and increased with increasing Gaussen Index in summer, in a similar way for both males and females. Hind foot length of males showed the same response. On the other hand, hind foot length of females decreased with increasing density only after dry summers, hence when environmental conditions were very harsh. Body condition was affected neither by density nor by drought intensity. Our results indicate that body mass and size are much better indicators of phenotypic quality than body condition in roe deer. The sex-specific responses of body size to environmental conditions could correspond to a differential allocation in favour of daughters by heavier than average roe deer mothers. [ABSTRACT FROM AUTHOR]

We analyzed spatial variations in movements and survival in a roe deer (Capreolus capreolus) population (Chizé, western France) by using recent developments of multistate Capture-mark-recapture modeling in order to estimate transition and survival probabilities of individuals living in three habitats of contrasting quality. Irrespective of both population density and sex, habitat quality did not influence survivorship of prime-age or senescent roe deer. Likewise, habitat quality did not influence fawn survival at low density. On the other hand, fawn survival at high density was 20% higher in the resource-rich hornbeam-dominant coppices than in the other poorer habitats. We found, as expected, that fawns were mobile, whereas adults of both sexes were highly sedentary. Movements of roe deer among habitats were markedly influenced by habitat quality. Transition probabilities of individuals from the rich hornbeam coppices toward other habitats were lower than transition probabilities of individuals from the poor beech stand or from the medium-quality maple dominant coppices toward the rich hornbeam coppices. [ABSTRACT FROM AUTHOR]

In most species of vertebrates, teeth play a central role in the long-term performance of individuals. However, patterns of tooth development have been little investigated as an indicator of animal performance. We filled this gap using data collected during long-term capture-mark-recapture monitoring of 1152 roe deer fawns at Chizé, western France. This population fluctuated greatly in size during the 27 years of monitoring, offering a unique opportunity to assess how the eruption patterns of front teeth perform as indicator of animal performance. We used three indices of the eruption of permanent front teeth, the simplest being whether or not incisor I2 has erupted, and the most complex being a 12-level factor distinguishing the different stages of tooth eruption. We also assessed the relevance of these indices as compared to fawn body mass, a widely used indicator of animal performance of deer populations. Dental indices and body mass were positively correlated (all r > 0.62). Similarly to body mass, all indices based on tooth eruption patterns responded to changes of population size and can be reliably used to assess the relationship between roe deer and their environment. We found a linear decrease in body mass with increasing population size (r² = 0.54) and a simultaneous delay in tooth development (r² = 0.48-0.55 from the least to the most accurate indicator). However, tooth development would be not further delayed in years with the highest densities (>15 adult roe deer/100 ha). A path analysis supported the population density effect on tooth eruption patterns being mainly determined by the effect of population size on body mass. Our study provides managers with simple indices (e.g., presence-absence of I2) that provide a technically more easy way to standardize measurements of deer density-dependent responses over large geographical and temporal scales than would be possible with body mass. [ABSTRACT FROM AUTHOR]