Adult Female Body Mass Research Articles

Correlating male white‐tailed deer antler size with female body mass across multiple spatial scales

AbstractManagers use morphometric data collected from harvested animals as indicators of nutritional condition. Antler or horn size often are considered in ungulates, but there are problems associated with biased and limited harvest data available from male animals in many populations. Adult female body mass also may be collected, but little information exists on how male antler size scales with female body mass. We evaluated the relationship between property‐specific mature male white‐tailed deer (Odocoileus virginianus) antler size and adult female body mass from harvest data collected at 2 spatial scales. Regression predicted a 4.4‐cm increase in average mature male antler size for every 1‐kg increase in female body mass from 31 properties across the eastern United States, 2015–2023. Adult female mass explained 64% of the variation in mature antler size, and including latitude as a covariate did not improve model fit. When we considered data from 174 properties in Mississippi, USA, 1991–1994, we predicted a 4.7‐cm increase in average mature male antler size for every 1‐kg increase in adult female body mass. Including soil resource region in the Mississippi model explained 48% of the variation in mature male antler size by accounting for differences in average sizes across regions. Our results indicate average female body mass correlates with mature male antler size at multiple spatial scales. We recommend managers collect body mass and age from harvested female deer, as female mass represents a useful metric to track management progress and predict changes in antler size.

Predictors of female American black bear body mass in an anthropogenic landscape

AbstractAnthropogenic pressure, such as urbanization and habitat loss, can wield many effects on wildlife that radiate through ecosystems. Large carnivores tend to experience these effects more severely than other species, diminishing their viability and altering ecosystem function by suppressing their role as an apex predator. Yet opportunistic carnivores that rely on an omnivorous diet can sometimes take advantage of anthropogenic food and improve their fitness prospects. We quantified the effect of phenotypic and ecological factors on female body mass of the American black bear (Ursus americanus) in New Jersey, USA. Habitat and reliable mast crops in New Jersey keep adult female black bear body mass and reproduction higher than many parts of the United States, and historically, female black bears in the mid‐Atlantic states tend to be larger than in other parts of their range. We used data collected from den surveys (n = 317) in northern New Jersey from 1984 to 2019 to examine the shared roles of climate, anthropogenic pressure (human food subsidies, harvest), habitat composition and configuration, natural food availability (hard mast production), and bear characteristics (age, history of human–black bear conflict) on female black bear body mass using generalized linear mixed models. Adult female body mass was heaviest with increased availability of cultivated crop and within low‐intensity developed land covers, suggesting anthropogenic food subsidies found in these 2 land cover types are contributing to female overall body mass. A history of conflict with humans explained heavier females, and a quadratic effect of age on body mass supported a senescent decline in adult female body mass later in life. Our results suggest that access to specific land cover types (i.e., crops, low‐intensity developments) that provide a diversity of food (e.g., corn, soft and hard mast) and support low human densities, explains female black bear body mass in a fragmented landscape.

Obstetric adaptation of the human pelvic inlet based on a sample of females and males matched for body size, and comparison with three species of primates that are sexually monomorphic in body size.

Human males are larger than females in body size; females are larger than males in pelvic size. Percentage pelvic sexual size dimorphism (sex with larger mean/sex with lower mean*100%) is used to infer selection for obstetric adaptation. As pelvic size is associated with body size, interpretation of percentage sexual size dimorphism necessitates control of body size. This study uses a larger sample of 221 females and 204 males to identify a subsample of females and males matched for femoral length, femoral head diameter, and clavicular length (25 females, 46 males). For five measures of the pelvic inlet, the human sample with control of body size is compared with three primate species that are sexually monomorphic in body size and give birth to newborns with higher relative body masses than those of humans: Aotus azarae (15 females, 19 males), Hylobates lar (29 females, 29 males), and Saguinus geoffroyi (28 females, 30 males). Results show that humans (112.0%) have the highest percentage sexual size dimorphism of pelvic inlet circumference: A. azarae (108.2%), H. lar (105.4%), and S. geoffroyi (103.3%). Humans have higher sexual size dimorphism of inlet circumference despite lower relative newborn body mass compared to the other species because human newborns are of larger body mass than predicted for an anthropoid with our adult female body mass. In humans, birthing of bigger babies than predicted for our body mass increases selection pressure on females for enlargement of the pelvic inlet.

Long-term variation in polar bear body condition and maternal investment relative to a changing environment

In the Arctic, warming air and ocean temperatures have resulted in substantial changes to sea ice, which is primary habitat for polar bears (Ursus maritimus). Reductions in extent, duration, and thickness have altered sea ice dynamics, which influences the ability of polar bears to reliably access marine mammal prey. Because nutritional condition is closely linked to population vital rates, a progressive decline in access to prey or an increase in the energetic cost of accessing prey has the potential to adversely affect polar bear population dynamics. We examined long-term (1983–2015) patterns of spring body condition (indexed using residual body mass) and maternal investment (i.e., litter mass of cubs-of-the-year and yearlings; COY and YRL) of polar bears from Alaska’s southern Beaufort Sea to evaluate potential relationships with regional- and circumpolar-scale sea ice conditions and atmospheric patterns. The length of the summer open-water (OW) season (i.e., the period of time the sea ice is mostly absent from the continental shelf) increased at a rate of 18 days decade-1 over the study period. However, the OW season duration was not a strong determinant of spring residual body mass or litter mass. Residual body mass of independent (i.e., subadults and adults) female bears varied relative to age class, reproductive status, and the strength of the prior winter’s Arctic Oscillation (i.e., a circumpolar-scale mode of climate variability driven by long-term atmospheric patterns). Spring residual mass of independent males varied with age class and variation in wind speed (i.e., regional-scale short-term atmospheric patterns) during the winter of the year preceding capture. Over the study period, mean annual body mass of adult females unaccompanied by COY declined by 4 kg/ decade-1, while no temporal trends were evident in the mean annual body mass of adult females with COY, adult males, and subadults. Litter mass of COY varied relative to capture date, maternal age class and mass, litter size, and year of capture. Litter mass of YRL varied with capture date, maternal age class and mass, litter size, variation in winter wind speed (the year of and year preceding capture), and the strength of the prior winter’s Arctic Oscillation. Mean annual litter mass of COY decreased at a rate of 2.6 kg decade-1 and declined 0.68 kg for every 10 kg reduction in maternal mass. No trend was evident in the mean annual litter mass of yearlings. These findings suggest a nuanced response of the southern Beaufort Sea polar bears to environmental change, where some demographic groups (e.g., adult males and subadults) are presently more resilient than others to changes in the Arctic marine ecosystem.

Long-term changes in occurrence, relative abundance, and reproductive fitness of bat species in relation to arrival of White-nose Syndrome in West Virginia, USA.

White‐nose syndrome (WNS) is a disease caused by the fungus Pseudogymnoascus destructans which has resulted in the deaths of millions of bats across eastern North America. To date, hibernacula counts have been the predominant means of tracking the spread and impact of this disease on bat populations. However, an understanding of the impacts of WNS on demographic parameters outside the winter season is critical to conservation and recovery of bat populations impacted by this disease. We used long‐term monitoring data to examine WNS‐related impacts to summer populations in West Virginia, where WNS has been documented since 2009. Using capture data from 290 mist‐net sites surveyed from 2003 to 2019 on the Monongahela National Forest, we estimated temporal patterns in presence and relative abundance for each bat species. For species that exhibited a population‐level response to WNS, we investigated post‐WNS changes in adult female reproductive state and body mass. Myotis lucifugus (little brown bat), M. septentrionalis (northern long‐eared bat), and Perimyotis subflavus (tri‐colored bat) all showed significant decreases in presence and relative abundance during and following the introduction of WNS, while Eptesicus fuscus (big brown bat) and Lasiurus borealis (eastern red bat) responded positively during the WNS invasion. Probability of being reproductively active was not significantly different for any species, though a shift to earlier reproduction was estimated for E. fuscus and M. septentrionalis. For some species, body mass appeared to be influenced by the WNS invasion, but the response differed by species and reproductive state. Results suggest that continued long‐term monitoring studies, additional research into impacts of this disease on the fitness of WNS survivors, and a focus on providing optimal nonwintering habitat may be valuable strategies for assessing and promoting recovery of WNS‐affected bat populations.

The effect of data provenance on estimates of gestation length in African and Asian colobines.

It seems to be commonly accepted that gestation length within the subfamily Colobinae lasts several weeks longer in the African tribe (Colobini) than in the Asian tribe (Presbytini) even though closely related taxa of similar body mass should have similar life histories. Suspecting problems with data provenance to cause the difference, we revisited the published records expecting similar gestation lengths in both tribes if based on vetted, accurate data. We compiled published gestation length data for Colobini and Presbytini, labeling them as "unspecified" (n=16) if the primary reference could not be located, methods were not described, and/or conceptions, the beginning of gestation, were determined based on sporadic observations of mating. If conceptions were determined based on changing hormone levels or patterns of daily mating records, we labeled the data as "accurate" (n=12). We analyzed the ln transformed data in a phylogenetic framework in relation to adult female body mass. In the unspecified dataset, gestation length in the two tribes overlapped extensively and did not differ significantly. However, in the accurate dataset, gestation length was significantly shorter in Colobini (not longer, as previously assumed). Data provenance had a strong impact on the comparison, reversing the relationship in gestation length in the two sister tribes. It remains to be determined why gestation lengths differ, whether, relative to the other primates, Colobini have a shortened gestation or Presbytini a lengthened gestation, and whether similar differences exist in other closely related taxa. Addressing these questions will require additional, broader, comparative analyses.

Land cover and weather jointly predict biometric indicators of phenotypic quality in a large herbivore

Body size and body mass are key indicators of individual phenotypic quality and predictors of important life-history traits such as survival and reproductive success. In wild herbivores, individual responses to changing environmental conditions influence morphometric traits over temporal scales and between populations. However, little research has assessed joint effects of weather and land use on body size/mass at finer, intra-population scale. We used data collected on female and juvenile red deer Cervus elaphus shot over a 17-year period (2001–2017) along two sides of a mountainous ridge largely differing in land cover and habitat productivity, to investigate how fine-scale land use patterns and weather influenced multiple morphometric indicators of phenotypic quality. Accounting for weather, body mass of all sex/age classes increased with increasing proportion of cultivated areas in the landscape and, for young females and calves, that increase was stronger or occurred only in the “low-quality” site. Other biometric traits such as mandible length and hind foot length showed the same pattern in young and calves, suggesting that body mass/size reflects individual responses especially in the early life-stage. Accounting for land use, body mass of adult females and calves was enhanced by increasing rainfall and decreasing temperature in spring-summer, i.e. favourable conditions for vegetation growth. This result also supports late gestation- and lactation-mediated effects of vegetation productivity on offspring quality. Additionally, in male calves, body mass and several other traits increased with decreasing severity of the previous winter, suggesting that quality of male offspring - but not that of females - could depend on winter conditions experienced in utero, likely due to higher maternal costs. Our findings emphasise how land cover and weather jointly affect indicators of phenotypic quality in a large mammal, helping to predict size responses of herbivores under the ongoing climatic- and anthropogenic land use-changes.

Heavy decline of the largest European Arctic Skua Stercorarius parasiticus colony: interacting effects of food shortage and predation

ABSTRACT Capsule The number of breeding pairs of Europe’s largest Arctic Skua Stercorarius parasiticus colony at Slettnes, Norway, showed a dramatic decline of at least 50% over two decades, with food shortage in four years and increasing predation by Red Fox Vulpes vulpes leading to total breeding failure in five out of six recent study years. Aims To document the decline of Europe’s largest Arctic Skua colony and quantify bottom-up and top-down effects on reproduction. Methods We compared nest counts between 1997–1998 and 2014–2019 and collected data on egg size, clutch size and nest success for all years, and adult body mass, nest attendance, at-sea activity, aggressive nest defence, Red Fox Vulpes vulpes encounters, daily nest survival and adult survival for 2014–2019. We deployed nest cameras to identify predators in 2018–2019. In addition, we developed a demographic model to estimate the fecundity required for a stable population. Results A higher proportion of time spent at sea, small eggs, low adult female body mass and indirect assessment of foraging fish availability suggested food shortages in four of six recent study years. At the same time, nest predation by Red Foxes, the likely predator involved, increased during the six-year study. The combined effects of food shortage and nest predation led to total breeding failures in 2017–2019. Conclusion We provide evidence of both bottom-up (food shortage) and top-down (predation) effects on reproductive investment and hatching success in this colony. The reproductive output in recent years is far too low to sustain a stable population. The severe decline of the Arctic Skua colony at Slettnes fits reported trends for this species across most of its European breeding range, as well as for its important host species, the Arctic Tern Sterna paradisaea and the Black-legged Kittiwake Rissa tridactyla.

Gestational weight gain in low-income and middle-income countries: a modelling analysis using nationally representative data

IntroductionGestational weight gain (GWG) has important implications for maternal and child health and is an ideal modifiable factor for preconceptional and antenatal care. However, the average levels of GWG across...

Costly teeth? Gestation length in primates suggests that neonate dentition is not expensive to produce.

Variation in the relationship between gestation length and body mass can arise because different types of tissue require varying amounts of energy to build, and not all species build such tissues in the same proportions. Given that a pregnant female has a finite amount of energy, trade-offs between investment in different tissues may occur. Here we examine if dental precocity accounts for variation in primate gestation length. If true, this could explain why folivorous species with precocial dentition have longer gestation lengths than predicted by neonatal brain and body mass. We compiled data on gestation length, neonate and adult female body and brain mass from the literature. We used published postcanine eruption schedules at 4 months of age and measured the total occlusal area as dental endowment to approximate dental precocity at birth. Species with embryonic delay in growth or altricial neonates were not considered because they represent grade shifts regarding gestation length. Consequently, our data were biased toward Simiiformes and Old World monkeys, specifically. We performed a phylogenetic generalized least squares regression (pGLS) of neonate brain mass in relation to neonate body mass, and a second pGLS with dental endowment as an additional predictor variable. Including dental endowment in the pGLS did not improve the model. Dental endowment did not systematically impact primate gestation length. Concordant with results from previous studies, this indicates that the energetically expensive period of tooth mineralization may occur postnatally. More data are required to examine if the results are typical across primates.

First evidence for a latitudinal body mass effect in extant Crocodylia and the relationships of their reproductive characters

AbstractRelationships between distribution patterns and body size have been documented in many endothermic taxa. However, the evidence for these trends in ectotherms generally is equivocal, and there have been no studies of effects in crocodylians specifically. Here, we examine the relationship between latitudinal distribution and body mass in 20 extant species of crocodylians, as well as the relationships between seven important reproductive variables. Using phylogenetically independent contrasts to inform generalized linear models, we provide the first evidence of a latitudinal effect on adult female body mass in crocodylians. In addition, we explore the relationships between reproductive variables including egg mass, hatchling mass and clutch size. We report no correlation between egg mass and clutch size, upholding previously reported within-species trends. We also find no evidence of a correlation between measures of latitudinal range and incubation temperature, contrasting with the trends found in turtles.

Subtle short-term physiological costs of an experimental augmentation of fleas in wild Columbian ground squirrels.

Parasites affect many aspects of host physiology and behavior, and thus are generally thought to negatively impact host fitness. However, changes in form of short-term parasite effects on host physiological markers have generally been overlooked in favor of fitness measures. Here, we studied flea (Oropsylla idahoensis and Oropsylla opisocroistis tuberculata) parasitism on a natural population of Columbian ground squirrels (Urocitellus columbianus) in Sheep River Provincial Park, AB, Canada. Fleas were experimentally added to adult female U. columbianus at physiologically demanding times, including birth, lactation and weaning of their young. The body mass of adult females, as well as their oxidative stress and immunity were recorded multiple times over the active season under flea-augmented and control conditions. We also measured the prevalence of an internal parasite (Trypanosoma otospermophili). Doubly labeled water (DLW) was intra-peritoneally injected at peak lactation to examine energy expenditure. Effects of parasites on oxidative stress were only observed after offspring were weaned. There was no direct effect of experimentally heightened flea prevalence on energy use. A short-term 24 h mass loss (-17 g) was detected briefly after parasite addition, likely due to U. columbianus preferentially allocating time for grooming. Our parasite augmentation did not strongly affect hosts and suggested that short-term physiological effects were unlikely to culminate in long-term fitness consequences. Columbian ground squirrels appear to rapidly manage parasite costs, probably through grooming.

Density has more influence than drought on spruce budworm (Choristoneura fumiferana) performance under outbreak conditions

Eruptive insect pests have significant impacts on the structure and function of forest ecosystems. Outbreaks of spruce budworm (Choristoneura fumiferana) (Clem.), for instance, occur approximately every 35–40 years, resulting in the loss of millions of hectares of spruce–fir forests in eastern North America. In addition to the density-dependent relationships that drive insect outbreaks, rising populations often coincide with drought events, which are expected to increase in both frequency and intensity in response to climate change. However, as populations approach the eruptive phase, consequences of intraspecific competition may outweigh the benefit of host water stress. The objective of our study was to quantify defoliation and insect performance responses to the interactive effects of drought and density of spruce budworm. To test for these interactions, we established a manipulative field experiment in a mature, balsam fir-dominated forest stand using a combination of single-tree rainout shelters and sleeve-caged insect larvae at four different densities: 0, 25, 50, or 100 individuals.Defoliation of 1-year old shoots, but not current-year shoots, significantly increased in response to higher insect densities. Density also had a significant, negative effect on budworm percent survival, although the total number of recovered adults remained highest in the high density treatment. Adult female body mass was significantly reduced in response to increased density, but only on droughted trees. Lastly, male wing length was significantly decreased in response to increased density. Overall, our results demonstrate that across a broad range of outbreak densities, rain exclusion had a minor impact. Accordingly, we anticipate that as insect pest populations approach epidemic levels, the influence of density on defoliation, insect survival, and body condition is likely to outweigh the impact of moderate drought stress.

Developments in development: What have we learned from primate locomotor ontogeny?

The importance of locomotion to evolutionary fitness has led to extensive study of primate locomotor behavior, morphology and ecology. Most previous research has focused on adult primates, but in the last few decades, increased attention to locomotor development has provided new insights toward our broader understanding of primate adaptation and evolution. Here, we review the contributions of this body of work from three basic perspectives. First, we assess possible determinants on the timing of locomotor independence, an important life history event. Significant influences on timing of locomotor independence include adult female body mass, age at weaning, and especially relative brain size, a significant predictor of other primate life history variables. Additionally, we found significant phylogenetic differences in the timing of locomotor independence, even accounting for these influences. Second, we discuss how structural aspects of primate growth may enhance the locomotor performance and safety of young primates, despite their inherent neuromotor and musculoskeletal limitations. For example, compared to adults, growing primates have greater muscle mechanical advantage, greater bone robusticity, and larger extremities with relatively long digits. Third, focusing on primate quadrupedalism, we provide examples that illustrate how ontogenetic transitions in morphology and locomotion can serve as a model system for testing broader principles underlying primate locomotor biomechanics. This approach has led to a better understanding of the key features that contribute to primates' stride characteristics, gait patterns, limb force distribution, and limb postures. We have learned a great deal from the study of locomotor ontogeny, but there is much left to explore. We conclude by offering guidelines for future research, both in the laboratory and the field.

Breeding biology of an endemic Bornean turdid, the Fruithunter (Chlamydochaera jefferyi), and life history comparisons withTurdusspecies of the world

ABSTRACT We present the first description of the breeding biology for the Fruithunter (Chlamydochaera jefferyi), a member of the cosmopolitan family Turdidae, and a montane endemic to the tropical Asian island of Borneo. We also compile breeding biology traits from the literature to make comparisons between the Fruithunter and the thrush genus Turdus. Our comparisons indicate that Fruithunters exhibit a slower life history strategy than both tropical and north temperate Turdus. We located and monitored 42 nests in 7 years in Kinabalu Park, Sabah, Malaysia. The mean clutch size was 1.89 ± 0.08 eggs, and the modal clutch size was 2 eggs. Mean fresh egg mass was 6.15 ± 0.13 g, representing 9.5% of adult female body mass. Average lengths of incubation and nestling periods were 14.56 ± 0.24 and 17.83 ± 0.31 days respectively. Only the female incubated and brooded the eggs and nestlings, but both the male and female fed nestlings. Female attentiveness during incubation was high throughout, reaching an asymptote...

Maternal winter body mass and not spring phenology determine annual calf production in an Arctic herbivore

Warming of the Arctic has resulted in earlier snowmelt and green‐up of plants in spring, potentially disrupting the synchrony between plant phenology and breeding phenology in herbivores. A negative relationship between offspring survival in West Greenland caribou and the timing of vegetation emergence was the first finding of such a mismatch in Arctic mammals. However, other studies indicate that the energy for foetal growth and early lactation is predominantly drawn from stored energy reserves typical of ‘capital’ breeders, suggesting that conditions well before spring influence calf production more than the timing of spring onset. Here we use 20 years of observations of marked Svalbard reindeer to evaluate determinants of annual recruitment, as measured by the presence of a calf at foot in mid‐summer. Spring temperatures and the enhanced vegetation index were used as proxies for spring onset, while data on body mass and pregnancy rates in late winter allowed us to determine maternal condition and the reproductive status before spring. Pregnancy rate, offspring survival and annual recruitment were all strongly correlated with average late winter adult female body mass (r = 0.87; r = 0.83; r = 0.92, respectively). Contrary to the findings in West Greenland, neither early calf survival nor annual recruitment were correlated with the two measures of annual variation in spring phenology (r = – 0.07, p = 0.8 and r = – 0.15, p = 0.6, respectively). We also revisit the Greenland data and reveal that the pattern of covariance between early and late measures of fecundity, as well as between early measures of fecundity and offspring survival, correspond with the results from Svalbard. Our results emphasize that conditions affecting maternal body mass during winter explain close to all the variation in recruitment, questioning the importance of the role of a mismatch between plant phenology and calving date.

Seasonal Dynamics of Mourning Dove (Zenaida macroura) Body Mass and Primary Molt

ABSTRACT Mourning Doves (Zenaida macroura) are common throughout much of North America and have been extensively studied. Seasonal changes in body mass are largely unreported and have not been examined in relation to replacement of primary flight feathers. We studied changes in body mass in relation to primary molt of doves captured in southeastern Arizona during 2000 through 2012. Body mass for adult males and females averaged 116.3 g (SE = 0.16) and 109.0 g (SE = 0.18), respectively. The distribution of body mass was similar for all months and was normally distributed. Body mass of adult males was lowest in August and September, and highest in November through January. Body mass of adult females was lowest in June through October and increased from October through March. Changes in body mass of adults generally tracked breeding and nesting activities and to a lesser extent timing of primary feather replacement. Body mass of juvenile doves increased linearly with replacement of juvenal primaries from pri...

The meaning of weaning in wild Phayre's leaf monkeys: Last nipple contact, survival, and independence

In primates and other mammals, weaning is an equivocal concept, as is reflected in the numerous ways it is measured: a) first intake of solid food, b) conflict over access to the nipple, c) ability to survive without mother, d) maternal resumption of cycling, or e) the cessation of nipple contact. The lack of a consistent definition means that weaning age, although it falls between gestation (fetal growth) and age at first reproduction (most energy diverted from growth), is currently not a reliable life history variable capturing offspring independence. Using data for wild Phayre's leaf monkeys (Trachypithecus phayrei crepusculus) at Phu Khieo Wildlife Sanctuary, Thailand (51 offspring, four groups), we asked whether the end of nipple contact indicates offspring independence as measured by survival to 3 years. To establish a baseline for the onset of independence, we assessed the youngest age at which individuals were orphaned (15-17 months) but then survived to 3 years. Next we determined that offspring age at last nipple contact (19.0 months) was comparable to two other independently calculated measures: offspring age at mother's first postpartum ovulation (11.5 months), and age at mother's re-conception (15.6 months). Using these separate "starting points," we arrived at similar ages for nipple contact cessation (18.4 and 19.2 months, respectively). Overall, in wild (but not in provisioned) Asian colobines, age at last nipple contact was allometrically related to adult female body mass, supporting its designation as a life history variable. Future comparisons need to show if this holds for other taxa.

DECREAsE IN THE BODY MAss OF WILD RINGTAILED LEMURs AT BERENTY REsERVE IN MADAGAsCAR WITH ENVIRONMENTAL CHANGEs

We measured the body mass of 76 (in 2006) and 73 (in 2011) wild ringtailed lemurs (Lemur catta) inhabiting the Berenty Reserve in Madagascar. Compared with the data recorded in 1999 (Koyama et al., 2008), the mean body mass of the adults had decreased significantly. In 2006, the adult females had decreased from 2.27 kg to 1.98 kg, and the adult males from 2.22 kg to 2.03 kg. In 2011, the body mass of both adult males and females was still 1.99 kg. In 2011, the group variations in body mass may have expanded. No sexual difference was observed in body mass, similar to the data from 1999. Despite their reduced body mass, adult females maintained a high birth rate (73.0% annually), but infant mortality was very high (86.2%) from 2006 to 2011. We discuss these phenomena with reference to environmental changes in this reserve .

Variation in adult body mass of roe deer: early environmental conditions influence early and late body growth of females

There is increasing evidence that environmental conditions experienced early in life can markedly affect an organism's life history, but the pathways by which early environment influences adult phenotype are poorly known. We used long-term data from two roe deer (Capreolus capreolus) populations (Chizé and Trois-Fontaines, France) to investigate the direct and indirect (operating through fawn body mass) effects of environmental conditions during early life on adult body mass. We found that environmental conditions (population size and spring temperatures) around birth influenced body mass of adult females through both direct and indirect effects in both populations. The occurrence of direct effects means that, for a given fawn body mass, adult female mass decreases with adverse conditions in early life. In contrast, we found no evidence for direct effects of early-life conditions on adult body mass of males, suggesting the existence of sex-specific long-term responses of body mass to stressful early conditions. Our results provide evidence that early environmental conditions influence the adult phenotype through persistent effects over the body development in wild mammal populations.