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Levels of random genetic drift are influenced by demographic factors, such as mating system, sex ratio and age structure. The effective population size (N e ) is a useful measure for quantifying genetic drift. Evaluating relative contributions of different demographic factors to N e is therefore important to identify what makes a population vulnerable to loss of genetic variation. Until recently, models for estimating N e have required many simplifying assumptions, making them unsuitable for this task. Here, using data from a small, harvested moose population, we demonstrate the use of a stochastic demographic framework allowing for fluctuations in both population size and age distribution to estimate and decompose the total demographic variance and hence the ratio of effective to total population size (N e /N) into components originating from sex, age, survival and reproduction. We not only show which components contribute most to N e /N currently, but also which components have the greatest potential for changing N e /N. In this relatively long-lived polygynous system we show that N e /N is most sensitive to the demographic variance of older males, and that both reproductive autocorrelations (i.e., a tendency for the same individuals to be successful several years in a row) and covariance between survival and reproduction contribute to decreasing N e /N (increasing genetic drift). These conditions are common in nature and can be caused by common hunting strategies. Thus, the framework presented here has great potential to increase our understanding of the demographic processes that contribute to genetic drift and viability of populations, and to inform management decisions., (© 2019 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

In species with sexual size dimorphism, the offspring of the larger sex usually have greater energy requirements and may lead to greater fitness costs for parents. The effects of offspring sex on maternal longevity, however, have only been tested in humans. Human studies produced mixed results and considerable debate mainly owing to the difficulty of distinguishing the effects of sexual dimorphism from sociocultural factors. To advance this debate, we examined how the relative number of sons influenced maternal longevity in four species of free-living ungulates (Soay sheep Ovis aries; bighorn sheep, Ovis canadensis; red deer, Cervus elaphus; mountain goat, Oreamnos americanus), with high male-biased sexual size dimorphism but without complicating sociocultural variables. We found no evidence for a higher cumulative cost of sons than of daughters on maternal longevity. For a given number of offspring, most females with many sons in all four populations lived longer than females with few sons. The higher cost of sons over daughters on maternal lifespan reported by some human studies may be the exception rather than the rule in long-lived iteroparous species.

Many environmental factors, such as annual precipitation, temperature variations, and the embedded stochasticity of natural systems, affect resource availability from one region to the next, such that animal survival and reproduction rates differ by region. For species exhibiting phenotypic plasticity, embedding phenotypes in a model of population dynamics becomes important, as region-driven plastic responses play a significant role when estimating parameters values. In this paper, we discuss how to include observable characteristics and climate patterns in estimates of reproduction rates of whitetail deer (Odocoileus virginianus). Using many studies already available in the literature, we establish a strong correlation between reproduction rate and both body weight and USDA plant hardiness zone. We demonstrate the accuracy of the estimated whitetail deer fecundity rates for various geographical regions in North America and show that Bergmann's rule is necessary to maintain similar biological fitness between various spatial distributions of deer populations. We demonstrate that the standard deviation of the weight distribution has almost no effect on reproduction rate estimates for adult deer populations. However, statistical analysis reveals sensitivity of fawn reproduction rates to environmental stochasticity. We incorporate the reproduction function in a stage- and gender-based model and prove the existence of a stable solution. Finally, we demonstrate a possible application of the model using harvested deer weights, without collecting reproduction data directly., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

White-tailed deer farming is a growing industry in the United States, yet there is still a need to improve breeding practices in captive cervids. The objective of this study was to compare reproductive and somatic characteristics of white-tailed bucks early in the breeding season (September), at peak rut (December), and late breeding season (March). We hypothesized that reproductive parameters would improve at the peak of the breeding season. Young, mature bucks (n = 7-11, ages 2-3 yr) were anesthetized via projector with tiletamine-zolazepam and xylazine. Semen was collected by electroejaculation and evaluated for sperm output, motility, and morphology. The bulbourethral, vesicular, and prostate glands were measured by transrectal ultrasound. Body condition score, thoracic circumference, rump fat thickness, scrotal circumference, and testicular measurements were also recorded. Serum testosterone, estradiol, and IGF-I concentrations were measured. Body condition score and rump fat thickness were highest in September, intermediate in December, and lowest in March (p < 0.01), whereas thoracic circumference was lowest in September (p = 0.02). In September, serum IGF-I was highest (p < 0.01) and estradiol was lowest (p ≤ 0.02). Serum testosterone levels were lowest in March and highest in December (p < 0.01). Testicular volume and scrotal circumference were highest in September, intermediate in December, and lowest in March (p < 0.01). Bulbourethral gland length was greatest in March (p ≤ 0.05), whereas prostate length was greatest in September (p ≤ 0.02). Vesicular gland length and width were highest in December, intermediate in September, and lowest in March (p ≤ 0.02). Both overall and progressive sperm motilities were lowest in March (p < 0.01), but did not differ between September and December (p ≥ 0.12). In December, bucks had the highest percentage of normal sperm and lowest percentage of primary sperm defects (p ≤ 0.01). Collectively, our results demonstrated variation in reproductive and metabolic characteristics of white-tailed deer bucks throughout the breeding season at 40°N. The physiological variations described here will be useful for veterinarians and researchers performing reproductive evaluations in white-tailed deer bucks., (Published by Elsevier Inc.)

In nature, individual reproductive success is seldom independent from year to year, due to factors such as reproductive costs and individual heterogeneity. However, population projection models that incorporate temporal autocorrelations in individual reproduction can be difficult to parameterise, particularly when data are sparse. We therefore examine whether such models are necessary to avoid biased estimates of stochastic population growth and extinction risk, by comparing output from a matrix population model that incorporates reproductive autocorrelations to output from a standard age-structured matrix model that does not. We use a range of parameterisations, including a case study using moose data, treating probabilities of switching reproductive class as either fixed or fluctuating. Expected time to extinction from the two models is found to differ by only small amounts (under 10%) for most parameterisations, indicating that explicitly accounting for individual reproductive autocorrelations is in most cases not necessary to avoid bias in extinction estimates., (© 2017 John Wiley & Sons Ltd/CNRS.)

Knowledge of reproductive characteristics of wild populations is necessary to inform responsible management decisions that promote herd health. As management, goals, and free-ranging populations change over time and landscapes, updated knowledge of reproductive characteristics are needed to inform responsible management practices. We estimated reproductive characteristics of female white-tailed deer in Illinois, including pregnancy rate, litter size, fetal growth and fetal sex ratio. We found maternal age to have an important influence on several reproductive factors. Approximately 66% of tested females (n = 3884) were pregnant and pregnancy rates increased with increasing maternal age, from 20.5% in fawns to 85.8% in adult deer. Litter size ranged from 1 to 5 fetuses per pregnant female. The average litter size was 1.9 ± 0.54 fetuses per pregnant female and also increased with age, from 1.2 in fawns to 2.0 in adults, respectively. Breeding season peaked in November with the mean estimated conception dates of fetuses varying with maternal age. Fawns conceived fetuses later in the breeding season (December 2) compared to yearlings and adults (November 11 and 8, respectively). We measured the body mass index (BMI) of all fetuses and found that litter size and female age influence fetal size. We found no bias in fetal sex ratio (average 1.0:1.0, male:female) but we observed a sex bias in fetal size (mean BMI male = 0.71, female 0.67) across all maternal age classes. A comparison of the current study and previous reports indicate that variation in maternal age within a population is an important driver of reproductive metrics, likely because maternal age and body size or condition are related. Furthermore, variation in resource availability will influence reproductive rates, especially among fawn females., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Female ungulate reproductive success is dependent on the survival of their young, and affected by maternal resource selection, predator avoidance, and nutritional condition. However, potential hierarchical effects of these factors on reproductive success are largely unknown, especially in multi-predator landscapes. We expanded on previous research of neonatal white-tailed deer (Odocoileus virginianus) daily survival within home ranges to assess if resource use, integrated risk of 4 mammalian predators, maternal nutrition, winter severity, hiding cover, or interactions among these variables best explained landscape scale variation in daily or seasonal survival during the post-partum period. We hypothesized that reproductive success would be limited greater by predation risk at coarser spatiotemporal scales, but habitat use at finer scales. An additive model of daily non-ideal resource use and maternal nutrition explained the most (69%) variation in survival; though 65% of this variation was related to maternal nutrition. Strong support of maternal nutrition across spatiotemporal scales did not fully support our hypothesis, but suggested reproductive success was related to dam behaviors directed at increasing nutritional condition. These behaviors were especially important following severe winters, when dams produced smaller fawns with less probability of survival. To increase nutritional condition and decrease wolf (Canis lupus) predation risk, dams appeared to place fawns in isolated deciduous forest patches near roads. However, this resource selection represented non-ideal resources for fawns, which had greater predation risk that led to additive mortalities beyond those related to resources alone. Although the reproductive strategy of dams resulted in greater predation of fawns from alternative predators, it likely improved the life-long reproductive success of dams, as many were late-aged (>10 years old) and could have produced multiple litters of fawns. Our study emphasizes understanding the scale-dependent hierarchy of factors limiting reproductive success is essential to providing reliable knowledge for ungulate management.

Natal features (e.g. Julian birth date and birth mass) often have fitness consequences and can be influenced by endogenous responses by the mother to seasonal fluctuations in nutritional quality and photoperiodic cues. We sought to further understand the biological and environmental factors that influence the natal features of a polytocous species in an environment with constant nutritional resources and limited seasonal variation. During a 36-year study we assessed the influence of biological factors (maternal age and litter type [i.e., litter size and sexual composition]) and environmental factors (total precipitation and mean maximum temperature during months encompassing conception, the last trimester of gestation, and the entire length of gestation) on Julian birth date and birth mass using linear-mixed effects models. Linear and quadratic functions of maternal age influenced both natal features with earliest Julian birth dates and heaviest birth masses occurring at prime-age and older individuals, which ranged from 5-9 years of age. Litter type influenced Julian birth date and birth mass. Interestingly, environmental factors affected Julian birth date and birth mass even though mothers were continuously allowed access to a high-quality diet. Random effects revealed considerable variation among mothers and years. This study demonstrates that, in long-lived polytocous species, environmental factors may have a greater influence on natal features than previously supposed and the influence from biological factors is also complex. The documented responses to environmental influences provide unique insights into how mammalian seasonal reproductive dynamics may respond to current changes in climate.

Coyotes recently expanded into the eastern U.S. and potentially have caused localized white-tailed deer population declines. Research has focused on quantifying coyote predation on neonates, but little research has addressed the potential influence of bedsite characteristics on survival. In 2011 and 2012, we radiocollared 65 neonates, monitored them intensively for 16 weeks, and assigned mortality causes. We used Program MARK to estimate survival to 16 weeks and included biological covariates (i.e., sex, sibling status [whether or not it had a sibling], birth weight, and Julian date of birth). Survival to 16 weeks was 0.141 (95% CI = 0.075-0.249) and the top model included only sibling status, which indicated survival was lower for neonates that had a sibling. Predation was the leading cause of mortality (35 of 55; 64%) and coyotes were responsible for the majority of depredations (30 of 35; 86%). Additionally, we relocated neonates for the first 10 days of life and measured distance to firebreak, visual obstruction, and plant diversity at bedsites. Survival of predation to 10 days (0.726; 95% CI = 0.586-0.833) was weakly associated with plant diversity at bedsites but not related to visual obstruction. Our results indicate that neonate survival was low and coyote predation was an important source of mortality, which corroborates several recent studies from the region. Additionally, we detected only weak support for bedsite cover as a covariate to neonate survival, which indicates that mitigating effects of coyote predation on neonates may be more complicated than simply managing for increased hiding cover.

The evolutionary theories of senescence predict that investment in reproduction in early life should come at the cost of reduced somatic maintenance, and thus earlier or more rapid senescence. There is now growing support for such trade-offs in wild vertebrates, but these exclusively come from females. Here, we test this prediction in male red deer (Cervus elaphus) using detailed longitudinal data collected over a 40-year field study. We show that males which had larger harems and thereby allocated more resources to reproduction during early adulthood experienced higher rates of senescence in both harem size and rut duration. Males that carried antlers with more points during early life did not show more pronounced declines in reproductive traits in later life. Overall, we demonstrate that sexual competition shapes male reproductive senescence in wild red deer populations and provide rare empirical support for the disposable soma theory of ageing in males of polygynous vertebrate species., (© 2014 The Author(s) Published by the Royal Society. All rights reserved.)

Breeding dispersal, defined as the net movement between successive breeding sites, remains a poorly understood and seldom reported phenomenon in mammals, despite its importance for population dynamics and genetics. In large herbivores, females may be more mobile during the breeding season, undertaking short-term trips (excursions) outside their normal home range. If fertilisation occurs, leading to gene flow of the male genome, this behaviour could be considered a form of breeding dispersal from a genetic point of view. Here, we investigated ranging behaviour of 235 adult roe deer using intensive GPS monitoring in six populations across Europe within the EURODEER initiative. We show that excursions are common from June to August among females, with 41.8% (vs. 18.1% of males) making at least one excursion. Most individuals performed only one excursion per season and departure dates for females were concentrated in time, centred on the rutting period, suggesting a link with reproduction. The distance females travelled during excursions was significantly greater than the site-specific average diameter of a male home range, while travel speed decreased once they progressed beyond this diameter, indicating search behaviour or interaction with other male(s) outside the resident male's territory. Because adults are normally highly sedentary, the potential for mating with relatives is substantial; hence, we conclude that rut excursions could be an alternative tactic enabling females to avoid mating with a closely related male. To understand better the ultimate drivers at play, it will be crucial to explore the genetic causes and consequences of this behaviour.

Our objectives were to determine if success index of pampas deer females is related with females' age and if social rank makes any influence on reproductive performance. Female social rank was determined in 18 groups of animals composed of 1 male: 5-9 females (total=98 females). Date of parturition for each female and sex and birth weight of fawns were recorded for each birth. The females were categorized in three hierarchical ranks: low (<0.33) (group LR), medium (0.33-0.66) (group MR), and high (>0.66) (group HR). The success index increased with age in pampas deer females (P<0.001). Social rank had no effect on calving success, relative calving dates, sex ratio or body weight at birth. In this study, the success index was related with females' age, and the reproductive performance did not differ between females of different social ranks., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A challenge in animal ecology is to link animal movement to demography. In general, reproducing and non-reproducing animals may show different movement patterns. Dramatic changes in reproductive status, such as the loss of an offspring during the course of migration, might also affect movement. Studies linking movement speed to reproductive status require individual monitoring of life-history events and hence are rare. Here, we link movement data from 98 GPS-collared female moose (Alces alces) to field observations of reproductive status and calf survival. We show that reproductive females move more quickly during migration than non-reproductive females. Further, the loss of a calf over the course of migration triggered a decrease in speed of the female. This is in contrast to what might be expected for females no longer constrained by an accompanying offspring. The observed patterns demonstrate that females of different reproductive status may have distinct movement patterns, and that the underlying motivation to move may be altered by a change in reproductive status during migration., (© 2014 The Author(s) Published by the Royal Society. All rights reserved.)

We examined the growth, reproduction, rutting behavior, and health status of sambar deer (Cervus unicolor brookei) in secondary Acacia mangium plantation. The data were collected over 11 years from a breeding herd of 21 stags and 33 hinds in Sabal Forest Reserve, Sarawak, Malaysia. Brody's growth model of the pooled data is Y t  = 148.56 (1 - 0.98e(-0.023t)), which estimates that maximum weights of adults are 184 and 115 kg for males and females respectively. Sambar deer are nonseasonal breeders with the breeding peak in February. Although the earliest age at which a female reached sexual maturity was 11 months, the mean age was 23 ± 7 months. Mean age of first fawning was 32 ± 8 months. Mean gestation period was 259 ± 12 days (n = 82). Stags shed antlers mostly between March and July. Velvet hardens at 103 ± 27 days (n = 23), and velvet harvesting is best at 7-9 weeks when antler length is 25-30 cm. Sambar deer are suitable as a farm species in forest plantations and have a vast potential to uplift rural living standards.

Bone accumulations faithfully record historical ecological data on animal communities, and owing to millennial-scale bone survival on high-latitude landscapes, have exceptional potential for extending records on arctic ecosystems. For the Porcupine Caribou Herd, maintaining access to calving grounds on the Arctic National Wildlife Refuge (ANWR, Alaska) is a central management concern. However, variability in calving ground geography over the 30+ years of monitoring suggests establishing the impacts of climate change and potential petroleum development on future calving success could benefit from extended temporal perspectives. Using accumulations of female antlers (shed within days of calving) and neonatal skeletons, we test if caribou calving grounds develop measureable and characteristic bone accumulations and if skeletal data may be helpful in establishing a fuller, historically integrated understanding of landscape and habitat needs. Bone surveys of an important ANWR calving area reveal abundant shed antlers (reaching 10(3) km(-2)) and high proportional abundance of newborn skeletal individuals (up to 60% neonate). Openly vegetated riparian terraces, which compose less than 10 per cent of ANWR calving grounds, yield significantly higher antler concentrations than more abundant habitats traditionally viewed as primary calving terrain. Differences between habitats appear robust to potential differences in bone visibility. The distribution of antler weathering stages mirrors known multi-decadal calving histories and highlights portions of the antler accumulation that probably significantly extends records of calving activity. Death assemblages offer historically integrated ecological data valuable for the management and conservation of faunas across polar latitudes.

The objectives of this study were to examine the effects of several factors affecting fawning rate, litter size, litter weight and neonatal fawn mortality in white-tailed deer inseminated either transcervically or by means of laparoscopy. Oestrus synchronisation with a controlled internal drug release (CIDR)-based protocol and fixed-time artificial insemination (FTAI) was conducted in 130 white-tailed deer (Odocoileus virginianus texanus) during three reproductive seasons (2007-2009; 271 services) in a game-hunting ranch in a hot-arid environment (26°4' N, 101°25' W). Ninety additional non-treated does were exposed to bucks for natural mating. Fawning rate did not differ between AI methods (40.0 vs 45.0% for transcervical and laparoscopic AI, respectively). Overall fawning rate (proportion of all does fawning after FTAI and a subsequent period of buck exposure) did not differ between transcervical (89.5%), laparoscopic (80.3%) or natural (88.9%) insemination. Litter size per fawning doe was higher (P<0.05) in naturally-served does (1.65±0.48) than in transcervically-inseminated does (1.40±0.51) or in laparoscopically-inseminated does (1.48±0.50). The main conclusion was that no enhancement of fawning rate or litter size occurred as a result of intrauterine deposition of semen by laparoscopy compared with the transcervical insemination technique.

The relative role of dynamic and fixed heterogeneity in shaping the individual heterogeneity observed in most life-history traits remains difficult to quantify. In a recent work, Tuljapurkar et al. (2009) suggested modeling individual heterogeneity in lifetime reproductive success by a null model building reproductive trajectories from a first-order Markov chain. According to this model, among-individual differences in reproductive trajectories would be generated by the stochastic transitions among reproductive states (such as breeder and non-breeder) due to dynamic heterogeneity. In this work, we analyze the individual variation in three reproductive metrics (reproductive status, fecundity, and reproductive success) in two populations of roe deer intensively monitored using Tuljapurkar et al. (2009)’s dynamic model. Moreover, we challenge the Tuljapurkar model previously used as a biological null model to test whether the observed distribution of reproductive success over the lifetime was generated by a stochastic process by modifying two steps of the previous model to build a full stochastic model. We show that a distribution generated by the full dynamic model proposed by Tuljapurkar et al. (2009) can be consistently interpreted as only generated from a stochastic biological process provided that the probabilities of transition among reproductive states used are independent of the current reproductive state and that the positive covariation that usually occurs between survival and reproduction among individuals is removed. Only the reproductive status of roe deer females could be restricted to a stochastic process described by the full stochastic model, probably because most females (>90%) were breeders in a given year. The fecundity of roe deer females could not be adequately described by the full dynamic and full stochastic model, and the observed distribution of female reproductive success differed from the one generated by a full dynamic model in which each individual reproductive trajectory was independent of the individual lifespan (second step of the full dynamic model changed). While there was clear evidence that dynamic heterogeneity occurred and accounted for a large part of the observed among-individual variation in reproductive trajectories of roe deer females, a stochastic process did not provide a suitable model for all reproductive metrics. Consequently, models including additional fixed and dynamic traits need to be built in order to separate the relative role of fixed and dynamic heterogeneities in generating reproductive trajectories.

Gonadotropin-releasing hormone is intermittently released from the hypothalamus in consistent patterns from before birth to final maturation of the hypothalamic-pituitary-gonadal axis at puberty. Disruption of this signaling via GnRH vaccination during the neonatal period can alter reproduction at maturity. The objective of this study was to investigate the long-term effects of GnRH-antibody exposure on reproductive maturation and function in elk calves passively exposed to high concentrations of GnRH antibodies immediately after birth. Fifteen elk calves (eight males and seven females) born to females treated with GnRH vaccine or sham vaccine during midgestation were divided into two groups based on the concentration of serum GnRH antibodies measured during the neonatal period. Those with robust (>15 pmol (125)I-GnRH bound per mL of serum) titers (N = 10; four females and six males) were designated as the exposed group, whereas those with undetectable titers (N = 5; three females and two males) were the unexposed group. Onset of puberty, reproductive development, and endocrine function in antibody-exposed and unexposed male and female elk calves were compared. Neonatal exposure to high concentrations of GnRH antibodies had no effect on body weight (P = 0.968), endocrine profiles (P > 0.05), or gametogenesis in either sex. Likewise, there were no differences between groups in gross or histologic structure of the hypothalamus, pituitary, testes, or ovaries. Pituitary stimulation with a GnRH analog before the second potential reproductive season induced substantial LH secretion in all experimental elk. All females became pregnant during their second reproductive season and all males exhibited similar mature secondary sexual characteristics. There were no differences between exposure groups in hypothalamic GnRH content (P = 0.979), pituitary gonadotropin content (P > 0.05) or gonadal structure. We concluded that suppressing GnRH signaling through immunoneutralization during the neonatal period likely does not alter long-term reproductive function in this species., (Published by Elsevier Inc.)

Social structure, limited dispersal, and spatial heterogeneity in resources are ubiquitous in wild vertebrate populations. As a result, relatives share environments as well as genes, and environmental and genetic sources of similarity between individuals are potentially confounded. Quantitative genetic studies in the wild therefore typically account for easily captured shared environmental effects (e.g., parent, nest, or region). Fine-scale spatial effects are likely to be just as important in wild vertebrates, but have been largely ignored. We used data from wild red deer to build "animal models" to estimate additive genetic variance and heritability in four female traits (spring and rut home range size, offspring birth weight, and lifetime breeding success). We then, separately, incorporated spatial autocorrelation and a matrix of home range overlap into these models to estimate the effect of location or shared habitat on phenotypic variation. These terms explained a substantial amount of variation in all traits and their inclusion resulted in reductions in heritability estimates, up to an order of magnitude up for home range size. Our results highlight the potential of multiple covariance matrices to dissect environmental, social, and genetic contributions to phenotypic variation, and the importance of considering fine-scale spatial processes in quantitative genetic studies., (© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.)

Knowledge of the reproductive biology is critical for the development of management strategies of the species both in captivity and in the wild, and to address conservation concerns regarding the sustainable use of a species. The present report characterizes some aspects of the reproductive biology of the wild red brocket deer inhabiting the North-eastern Peruvian Amazon region, based on the anatomical and histological examination of the female reproductive organs of 89 wild adult females in different reproductive states. The red brocket deer female presented ovarian follicular waves involving the synchronous growth of a cohort of an average 25 follicles but only one follicle generally survived and continued development, reaching maturity at 4mm. Mean ovulation rate was 1.14 and litter size was 1 fetus. Females presented a low rate of reproductive wastage of 14.3% of embryos. Among the 89 adult females studied, 41 (46.1%) were pregnant and 48 (53.9%) were non-pregnant females. In the Northeastern Peruvian Amazon, conceptions occurred year-round in the red brocket deer but there were peaks in the rate of conception. Estimated yearly reproductive production was 0.76-0.82 young per adult female. Most pregnant females in advanced stage of pregnancy had at least one active CL, suggesting the persistence of CL throughout gestation., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Reproductive performance of 750 adult female Forest musk deer (FMD, Moschus berezovskii) was monitored (from 2005 to 2009) on two Forest musk deer farms in Sichuan province, China. The mean (± SEM) lengths of the estrous cycle, pregnancy, and consecutive fawning intervals were 17.5 ± 0.8 d (n = 64), 182.9 ± 0.8 d (n =190), and 363.2 ± 2.4 d (n = 120), respectively. Copulation occurred from the end of October to early March, with the majority (84.1 ± 1.9%) during November and December (P < 0.05). The fawning rate was 68.7 ± 2.2% in yearling hinds and 73.3 ± 1.3% in adult hinds. Fawning occurred from the end of April to early September, with the majority (88. 9 ± 2.2%) during May and June (P < 0.005), including a peak in May (52.0 ± 1.0%). Yearling hinds fawned later (7.3 ± 1.8 d) than adult hinds. Rates of premature delivery and dystocia were 2.7 ± 0.4 and 2.0 ± 0.3%, respectively. There was a 1.07:1 female-to-male ratio at birth (P > 0.05), with 67.7% twins, but only two cases of triplets and one set of quadruplets among 537 fawns. Birth weight averaged 518.7 ± 10.3 g, ranging from 304 to 775 g (n = 240), with male fawns slightly heavier than females (521.1 ± 14.8 vs 516.9 ± 14.3 g). Postnatal and pre-weaning mortality rates were 25.0 ± 1.2 and 17.9 ± 3.1%, respectively. Postnatal mortality and urinary calculus were much more common in male fawns (P < 0.01). The mortality rate due to suppuration and dyspepsia were different (P < 0.001) between postnatal and pre-weaning periods. Due to higher mortality of male fawns, the adult sex ratio was significantly female-biased. In conclusion, captive FMD had similar seasonal patterns of copulation and fawning as wild FMD and other musk deer species., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The cervids are a complex assemblage of taxa showing extreme diversity in morphology, physiology, ecology and geographical distribution. Reproductive strategies adopted by various species are also diverse, and include a range from highly seasonal to completely aseasonal birth patterns. The recent growth in knowledge on cervid reproduction is strongly biased towards the larger-bodied, gregarious mixed grazer-browser species that have adapted well to human management and commercialisation. These species tend to represent 'K-selected' climax species characterised by very productive annual breeding success, singleton births and long breeding life (10+ years). Conversely, we know relatively little about the reproductive patterns of the 'r-selected' smaller-bodied, solitary (and often highly territorial), forest-dwelling browser species, often characterised by great fecundity (twinning) and shorter breeding life (<10 years). This group includes many of the endangered cervid taxa. This review extends earlier reviews to include more recent work on cervid reproductive cycles, particularly in relation to environmental factors influencing gestation length., (Copyright © 2010 Elsevier B.V. All rights reserved.)

1. Trade-offs among life-history traits are common because individuals have to partition limited resources between multiple traits. Reproductive costs are generally assumed to be high, resulting in reduced survival and fecundity in the following year. However, it is common to find positive rather than negative correlations between life-history traits. 2. Here, we use a data set from the individual-based study of red deer on the Isle of Rum to examine how these costs vary between individuals and at different ages, using multi-state mark-recapture methodology. 3. Females that had reproduced frequently in the past incurred lower costs of reproduction in terms of survival in the following year and were more likely to reproduce in two consecutive years. Older individuals and those that had not reproduced frequently exhibited higher costs. 4. These results highlight the importance of considering heterogeneity and individual quality when examining trade-offs and demonstrate the effectiveness of using detailed long-term data sets to explore life-history strategies using multi-state mark-recapture models., (© 2010 The Authors. Journal of Animal Ecology © 2010 British Ecological Society.)

The births of brown brocket deer ( Mazama gouazoubira) in a secondary lower montane forest called "yunga" in northwestern Argentina were compared with rainfall. Analyses were performed with rainfall and flower-fruit fall in an attempt to determine the possible importance of these seasonal variables in birthing. The births were not directly correlated with rainfall, but rather with the flower and fruit fall of exotic plant species. This may be related to favor the development of fawns, which eat the new and more digestible plant parts, accessible one month after their births.The non-seasonal births observed around the year could be related to the selection by the deer of some plant species that have been introduced into the region (Prunus, Morus and Psidium), have a longer fruiting span than the scarce native plant species.

In polygynous species, adult mortality is generally higher in males than in females, and theory predicts that this should result in the evolution of faster rates of senescence in males. Detailed investigations of sex differences in patterns of aging across the many and varied phenotypic characteristics associated with successful reproduction in wild populations of polygynous vertebrates are currently lacking. Here, we use longitudinal data collected from a wild red deer population to compare aging patterns across a range of life-history, behavioral, and morphological traits in both sexes. While males showed more rapid age-related declines in annual breeding success than did females, there was evidence of variation in aging rates among traits within each sex. Traits associated with male breeding performance showed a rapid decline in old age, whereas the morphology and phenology of antlers, a key male secondary sexual characteristic, showed minimal senescence. Female reproductive traits associated with regulation of estrus and gestation showed delayed senescence relative to traits associated with investment in offspring growth during gestation and lactation. Our results suggest that either natural selection or physiological constraint has caused an uncoupling of senescence rates in different physiological systems and, thus, different reproductive traits in this wild vertebrate population.

Predators affect prey demography through direct predation and through the costs of antipredator behavioral responses, or risk effects. Experiments have shown that risk effects can comprise a substantial proportion of a predator's total effect on prey dynamics, but we know little about their strength in wild populations, or the physiological mechanisms that mediate them. When wolves are present, elk alter their grouping patterns, vigilance, foraging behavior, habitat selection, and diet. These responses are associated with decreased progesterone levels, decreased calf production, and reduced population size [Creel S, Christianson D, Liley S, Winnie JA (2007) Science 315:960]. Two general mechanisms for the effect of predation risk on reproduction have been proposed: the predation stress hypothesis and the predator-sensitive-food hypothesis. Here, we used enzyme immunoassay to measure fecal glucocorticoid metabolite concentrations for 1,205 samples collected from 4 elk populations over 4 winters to test the hypothesis that the effect of predation risk on elk reproduction is mediated by chronic stress. Across populations and years, fecal glucocorticoid concentrations were not related to predator-prey ratios, progesterone concentrations or calf-cow ratios. Overall, the effect of wolf presence on elk reproduction is better explained by changes in foraging patterns that carry nutritional costs than by changes in glucocorticoid concentrations.

1. A wide range of measures are used to quantify 'individual quality', with the term often used but not defined. 2. Here we use detailed data from a population of red deer (Cervus elaphus) to assess whether frequently used measures of individual quality are well correlated, and therefore likely to lead to comparable ecological and evolutionary insight in analyses. 3. Correlations between measures were usually small, indicating that individuals may be considered high quality for one trait, but low quality for another. 4. By using principal component analysis, we illustrate that there are potentially many varied individual life-history tactics within a population. 5. This variation in tactics makes it challenging to characterize individual quality as a simple scalar; measures of heterogeneity in ecological studies should therefore be both species and question specific.

1. Although life-history theory predicts substantial costs of reproduction, individuals often show positive correlations among life-history traits, rather than trade-offs. The apparent absence of reproductive costs may result from heterogeneity in individual quality. 2. Using detailed longitudinal data from three contrasted ungulate populations (mountain goats, Oreamnos americanus; bighorn sheep, Ovis canadensis; and roe deer, Capreolus capreolus), we assessed how individual quality affects the probability of detecting a cost of current reproduction on future reproduction for females. We used a composite measure of individual quality based on variations in longevity (all species), success in the last breeding opportunity before death (goats and sheep), adult mass (all species), and social rank (goats only). 3. In all species, high-quality females consistently had a higher probability of reproduction, irrespective of previous reproductive status. In mountain goats, we detected a cost of reproduction only after accounting for differences in individual quality. Only low-quality female goats were less likely to reproduce following years of breeding than of nonbreeding. Offspring survival was lower in bighorn ewes following years of successful breeding than after years when no lamb was produced, but only for low-quality females, suggesting that a cost of reproduction only occurred for low-quality females. 4. Because costs of reproduction differ among females, studies of life-history evolution must account for heterogeneity in individual quality.

We used long-term data on movements, survival, and reproduction of female red deer (Cervus elaphus Linnaeus) of the Isle of Rum, Scotland (1970-2001), to explain variation in life history (age at maturity) from a hind's access to habitat resources and exposure to local density, and cross-generational (maternal) effects on observed relationships. We described each hind's use of resources relative to availability in the study area from an individual-based resource selection function (RSF); we defined local density as the total number of hinds aged > or = 1 year within the subpopulation cluster to which an individual belonged. The likelihood of a hind producing her first calf in the period from birth to the end of the summer in which she turned age 3 was positively related to relative use of Agrostis/Festuca grasslands and other low-elevation communities, and inversely related to a hind's mean annual local density. However, when we considered both a daughter's RSF and exposure to local density and her mother's RSF and exposure to local density, maternal data alone most parsimoniously explained variation in age at maturity of daughters. Mothers were able to lower age at maturity in their daughters in two, non-mutually exclusive ways. First, birth mass of daughters was inversely related to age at maturity, and mothers that used relatively less uplands (Calluna-dominated heath and heather moorland) and occupied areas of lower density produced larger offspring. Second, mothers could establish a home range that enabled daughters to mature in areas with access to high quality Agrostis/Festuca grasslands at low density. Lifetime reproductive success was inversely associated with a hind's age at maturity via extension of the reproductive life span. Longevity did not change in association with age at maturity. Patterns in how animals use available habitat resources may depend on that of previous generations, especially at larger scales of resource selection.

The cost of reproduction can generate covariation between demographic rates that can potentially influence demography and population dynamics in long-lived iteroparous species. However, there has been relatively little work linking the survival cost of reproduction and population dynamics. The apparent scarcity of information on this important link is potentially due to covariation between vital rates, which can substantially influence fluctuations in population size. In this paper we examine the opportunity for survival costs of reproduction to leave a dynamic signature using a simulation model based broadly on an ungulate life history. We find that an increase in the cost delays the onset of reproduction and reduces reproductive rates of young, but not of prime-age, females. Accordingly, the number of offspring produced declines and the interval between reproductive events increases among young females experiencing high cost. These effects are translated to an age structure skewed toward young ages and reduced population density. These results suggest that, by delaying reproduction when conditions deteriorate, females protect their survival during the critical first three years of life, after which the negative effect of reproduction on survival declines. Unless conditions for reproduction are severe, it is not profitable to delay reproduction beyond age 3 years due to the high risk of death before having a chance to reproduce. We also demonstrate that lack of adjustment of reproductive strategies to elevated levels of the cost of reproduction, for example due to rapid changes in environmental conditions, results in lower average density and longevity compared to females that have sufficient time to adjust to changes in the cost. This suggests that even moderate costs of reproduction may have a major negative effect on population dynamics of ungulates.

An insular population of white-tailed deer Odocoileus virginianus introduced in 1896 to predator-free Anticosti Island, Quebec, has caused long-term changes in the plant community. Food quality declined as did body weight. Although different parameters of reproduction changed, overall reproductive rates remained similar, thus maintaining deer density and promoting further change in habitat. These results show (i) long-term feedbacks on carrying capacity, (ii) the mechanism for reduction of body mass, and (iii) the lack of strong reduction in reproductive rates to regulate the population at high density, a feature of Eutherians. They are relevant to mechanisms determining the evolution of vertebrate body sizes.

1. Increasing ungulate populations are affecting vegetation negatively in many areas, but few studies have assessed the long-term effects of overbrowsing on individual life-history traits of ungulates. 2. Using an insular population of white-tailed deer (Odocoileus virginianus Zimmermann; Anticosti, Québec, Canada) introduced in 1896, and whose density has remained high since the first evidence of severe browsing in the 1930s, we investigated potential feedbacks of long-term and heavy browsing on deer life-history traits. 3. We assessed whether chronic browsing contributed to a decline of the quality of deer diet in early autumn during the last 25 years, and evaluated the impacts of reduced diet quality on deer body condition and reproduction. 4. Rumen nitrogen content declined 22% between two time periods, 1977-79 and 2002-04, indicating a reduction in diet quality. 5. After accounting for the effects of year within the time period, age and date of harvest in autumn, peak body mass of both sexes declined between the two time periods. At the end of November, males were on average 12% heavier and adult does 6% heavier in 1977-79 than in 2002-04. Hind foot length did not vary between time periods. 6. The probability of conception increased 15% between the two time periods, but litter size at ovulation declined 7%, resulting in a similar total number of ovulations in 2002-04 and in 1977-79. 7. Our results suggest that following a decline in diet quality, white-tailed deer females modified their life-history strategies to maintain reproduction at the expense of growth. 8. Deer appear to tolerate drastic reductions in diet quality by modifying their life history traits, such as body mass and reproduction, before a reduction in density is observed. Such modifications may contribute to maintain high population density of large herbivores following population irruption.

The pampas deer (Ozotoceros bezoarticus) is a South American grazing deer which is in extreme danger of extinction. Very little is known about the biology of the pampas deer. Moreover, most information has not been published in peer-reviewed scientific journals, and is only available in local publications, theses, etc. Therefore, our aim was to update and summarize the available information regarding the reproductive biology of the pampas deer. Moreover, in most sections, we have also included new, unpublished information. Detailed descriptions are provided of the anatomy of both the female and the male reproductive tract, puberty onset, the oestrous cycle and gestational length. Birthing and the early postpartum period are described, as are maternal behaviour and early fawn development, seasonal distribution of births, seasonal changes in male reproduction and antler cycle, reproductive behaviour, semen collection, and cryopreservation. Finally, an overview is given and future directions of research are proposed.

1. In large herbivores, the timing of breeding is important for females to hit peak plant protein levels. For males, the timing of reproductive effort is important to maximize the number of females they can mate during autumn rut in competition with other males. The latter depends on when most females are ovulating, but also on how other males with a different competitive ability are timing use of their capital (fat); it may pay younger males to invest more heavily later when prime aged males are exhausted. 2. Based on estimates of body mass loss, we quantify how much timing (start, peak and end dates) of male reproductive effort during rutting varies depending on male age, density and climate as well as timing of female ovulation. 3. Ovulation in adult females was delayed by 5 days from low to high density, and ovulation was also more synchronous at high density. The starting date of decline in male body mass was only later in yearlings than among other age groups. However, at low density, peak and end dates of rut became increasingly earlier and close to peak female ovulation with increasing age up to 7 years of age. Prime-aged males matched peak effort closely with peak rate of prime-aged female ovulation, while younger males were delayed. This is consistent with the view that younger males have a better chance when the prime-aged males are becoming exhausted. 4. Apart from yearlings, male age groups were synchronized in both the starting, peak and end dates of mass decline at high density. Thus, this partly follows change in female ovulation patterns, but also suggests that competition among males decreased with increasing density due probably to lower intensity of sexual selection. The lowered sexual selection may be due not only to more synchronous female ovulation, but also increasingly female-biased sex ratios and a younger male age structure with increasing density. 5. The onset of rutting is somewhat independent of male age (apart from the youngest males), but the peak and end of rutting effort is dependent strongly upon age, density and peak female ovulation. Male rutting phenology is thus best interpreted as a compromise between hitting peak female ovulation and intensity of sexual selection.

Because there is a paucity of information on the mineral requirements of free-ranging deer, data are needed from clinically healthy deer to provide a basis for the diagnosis of mineral deficiencies. To our knowledge, no reports are available on baseline hepatic mineral concentrations from sympatric white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) using different habitats in the Northern Great Plains. We assessed variation in hepatic minerals of female white-tailed deer (n = 42) and mule deer (n = 41). Deer were collected in February and August 2002 and 2003 from study areas in Custer and Pennington Counties, South Dakota, in and adjacent to a wildfire burn. Hepatic samples were tested for levels (parts per million; ppm) of aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), nickel (Ni), phosphorus (P), potassium (K), selenium (Se), sodium (Na), sulfur (S), thalium (Tl), and zinc (Zn). We predicted that variability in element concentrations would occur between burned and unburned habitat due to changes in plant communities and thereby forage availability. We determined that Zn, Cu, and Ba values differed (P

The relationship between individual performance and nonrandom use of habitat is fundamental to ecology; however, empirical tests of this relationship remain limited, especially for higher orders of selection like that of the home range. We quantified the association between lifetime reproductive success (LRS) and variables describing lifetime home ranges during the period of maternal care (spring to autumn) for 77 female roe deer (Capreolus capreolus) at Trois-Fontaines, Champagne-Ardenne, France (1976-2000). We maintained population growth rate (adjusted to account for removals of non-focal animals) near rmax, which enabled us to define the fitness-habitat relationship in the absence of density effects. Using a negative binomial model, we showed that a roe deer's incorporation into its home range of habitat components important to food, cover, and edge (meadows, thickets, and increased density of road allowances) was significantly related to LRS. Further, LRS decreased with increasing age of naturally reclaimed meadows at the time of a deer's birth, which may have reflected a cohort effect related to, but not entirely explained by, a decline in quality of meadows through time. Predictive capacity of the selected model, estimated as the median correlation (rs) between predicted and observed LRS among deer of cross-validation samples, was 0.55. The strength of this relationship suggests that processes like selection of the site of a home range during dispersal may play a more important role in determining fitness of individuals than previously thought. Individual fitness of highly sedentary income breeders with high reproductive output such as roe deer should be more dependent on home range quality during the period of maternal care compared to capital breeders with low reproductive output. Identification of the most important habitat attributes to survival and reproduction at low density (low levels of intraspecific competition) may prove useful for defining habitat value ("intrinsic habitat value").

1. Molar tooth wear is considered an important proximate mechanism driving patterns of senescence in ungulates but few studies have investigated the causes of variation in molar wear or their consequences for reproductive success. 2. In this study, we assessed molar tooth wear at death among red deer Cervus elaphus of known age on the Isle of Rum, Scotland. 3. First molar height showed a decelerating decline with age. In females, the rates of molar wear with age varied with location of home range and individuals experiencing low resource competition showed reduced molar wear. We suggest that this spatial variation in molar wear is related to differences in the availability of high-quality grazing habitat and levels of resource competition. 4. There was no evidence that females with more heavily worn molars had reduced reproductive performance late in life or that first molar height was associated with reproductive senescence.

Elk (Cervus elaphus) in the Greater Yellowstone Ecosystem alter patterns of aggregation, habitat selection, vigilance, and foraging in the presence of wolves (Canis lupus). Antipredator behaviors like these can reduce predation risk but are also likely to carry costs. Data from five elk populations studied for 16 site years showed that progesterone concentrations (from 1489 fecal samples) declined with the ratio of elk to wolves. In turn, progesterone concentrations were a good predictor of calf recruitment in the subsequent year. Together, these data suggest that wolves indirectly affect the reproductive physiology and the demography of elk through the costs of antipredator behavior.

This study investigates the validity of current theory for predicting ecological and allometric effects on space use, social structure and mating systems of poorly known solitary cervids, based on a comparative analysis of radio-telemetry data on hog deer Axis porcinus (N=32) and Indian muntjac Muntiacus muntjak (N=28). The larger and sexually size-dimorphic hog deer inhabit highly productive alluvial floodplains, where resource distribution is patchy and spatiotemporally unpredictable. As predicted for this species, site fidelity was low and range sizes varied among sex and age groups and among seasons. Hog deer were probably non-territorial, as home range sizes seemed too large to be exclusive when taking into account their high population density. Extensive movements of adult males during the rut implied "roaming" as a mating strategy. The smaller, forest-dwelling and sexually size-monomorphic muntjacs inhabit a more uniform and stable habitat. As predicted, muntjacs exhibited higher site fidelity than hog deer, and no seasonal variations in home range sizes. Adults exhibited relatively large home range overlap, both inter- and intrasexually. Hence, strict territoriality did not occur, but their well-defined home ranges and high site fidelity indicated some form of site-specific dominance. In conclusion, habitat characteristics were appropriate predictors of home range sizes and site fidelity. Body mass appeared to be a suitable predictor of intraspecific patterns in space use but a poor predictor of interspecific patterns, probably due to a confounding effect of habitat productivity.

The effects of vaginal implant transmitters for tissue damage after 11 wk in 13 captive adult elk (Cervus elaphus nelsoni) and subsequent reproductive performance in 38 free-ranging elk were evaluated. Vaginal implant transmitters are designed to be shed at parturition and are used to locate birth sites of wild ungulates; however, potential adverse effects of these transmitters on tissues associated with the vaginal walls or subsequent reproductive performance have not been assessed. Vaginal implant transmitters consist of a transmitter encased in inert acrylic with an antenna trailing out the distal end and wings at the proximal end to hold the transmitter in place. Using a laparoscope on sedated captive elk, necrosis or measurable differences in tissue trauma between designs with wing spans of 80 versus 150 mm over an 11-wk trial were not observed. After the captive elk trial, vaginal implant transmitters with 80-mm wings were placed into 38 pregnant wild elk, and 31 live births were documented. Fates of seven calves were not determined, because their transmitters were not shed at the birth site. We recaptured 36 of these cow elk again in fall 2003 or spring 2004, and 32 were pregnant. This study was unable to document any short- or long-term effects of vaginal implant transmitters on reproductive performance of cow elk in captive and free-range environments.

Individuals are predicted to maximize lifetime reproductive success (LRS) through selective use of resources; however, a wide range of ecological and social processes may prevent individuals from always using the highest-quality resources available. Resource selection functions (RSFs) estimate the relative amount of time an individual spends using a resource as a function of the proportional availability of that resource. We quantified the association between LRS and coefficients of individual-based RSFs describing lifetime resource selection for 267 female red deer (Cervus elaphus) of the Isle of Rum, Scotland, from 1970 to 2001. LRS was significantly related to first- and second-order effects of selection for Agrostis/Festuca grassland and proximity to the sea coast (quality of forage within Agrostis/Festuca grassland was highest nearest the coast (ratio of short:long grassland)). The benefits of selecting for quality in Agrostis/Festuca grassland, however, traded-off with increases in LRS gained by avoiding conspecific density. LRS was inversely associated with local density, which was highest along the coast, and reproductive benefits of selecting Agrostis/Festuca grassland diminished with increasing density. We discuss the relevance of these results to our understanding of the spatial distribution of red deer abundance, and potential applications of our approach to evolutionary and applied ecology.

Calving date in many mammals is matched to the time of greatest food availability. Out of season calving results in heavy penalties in terms of own and offspring survival or body condition. This study examined whether gestation length is affected by advancing fertilisation. Thirty-six red deer hinds (of the Iberian and Scottish subspecies) were subjected to a synchronisation treatment of oestrus, ovulation, and artificial insemination on three dates, with remaining non-pregnant females mated with an intact male in a last group. Gestation was longer the more the fertilisation was advanced; gestation lasted 241.5+/-1.3 days (d) in the first group, 237.4+/-1.2 d in the second, 235.1+/-1.3 d in the third, and 231.2+/-1.6 d in the last. Mean gestation lasted 234.2+/-0.7 d. Hinds gained less weight during gestation the more the fertilisation was advanced. The difference was due at least in part to net body weight of the hind after calving compared to that at mating, and calves did not differ in birth weight. As early born calves suffer greater mortality in the field, this enlargening of gestation might be a compensatory response of the hinds to match calving with food availability. Under natural conditions, similar small modifications of gestation length may help hinds to overcome short-term adverse conditions for calving. Because calf mortality is correlated with birth weight, hinds may have kept calf birth weight constant at the expense of greater body weight loss.

North American farmed elk (Cervus elaphus) producers were surveyed to determine period specific rates of calving, abortion, and dystocia, and to examine the effect of reproduction-related mortality on the productivity of farmed elk. The overall calving rate was 86.3% and the calving rate for adult cows was found to be significantly higher than that for heifers. Abortions were seen on 7.6% of farms and the overall abortion rate was approximately 0.6%. Dystocia was experienced in 5.9% of births. Neonatal mortality, summer mortality, weaning mortality, and postweaning mortality rates were calculated and compared. Failure to produce a live neonate was responsible for 64% of the total reproductive loss and calf mortalities from birth to 1 year of age accounted for 36%. Failure to produce a live neonate had a more significant effect on productivity than did mortalities from birth to 1 year of age, suggesting that reproduction has a greater economic effect on elk farms than neonatal mortality.

In this study, a commercial enzyme immunoassay (EIA) was validated in detecting glucocorticoids in Pampas deer feces, in order to investigate the influence of several factors on the adrenocortical function. Fecal samples, behavioral data and information concerning male grouping and antlers status were collected at a monthly basis during a 1 year period from free-ranging stags living at Emas National Park, Brazil (18 degrees S/52 degrees W). The results revealed that concentrations of fecal glucocorticoids in winter were significantly higher than those corresponding to spring and summer. In addition, dry season data presented higher levels than during the wet season. Significant difference was found between fecal levels of breeding stags in summer and nonbreeding stags, whereas no difference was observed between breeding stags in winter and nonbreeding stags. On the other hand, males from areas with frequent human disturbance exhibited higher glucocorticoid concentrations and flight distances than individuals from areas of lower human activity. Males with antlers in velvet had elevated levels compared with animals in hard antler or antler casting. Also, we found that glucocorticoid levels were higher in groups with three or more males than in groups with only one male. The flight distances showed positive correlation with fecal glucocorticoid. These data indicate that fecal glucocorticoid provides a useful approach in the evaluation of physiological effects of environment, inter-individuals relationship and human-induced stressors on free-ranging Pampas deer stags.

Low reproductive productivity of young red deer (Cervus elaphus) hinds on New Zealand deer farms appears to reflect high incidences of puberty failure at 16 months of age. This is despite the general attainment of average liveweights 15-25 kg in excess of the accepted minimum threshold for puberty in subspecies of western European origin (scoticus, elaphus and hippelaphus) that form the basis of the national herd. The present study tests the hypotheses that introgression of the larger North American wapiti subspecies (nelsoni, manitobensis and roosevelti) into breeding herds (1) can be assessed from morphological features of individuals, (2) that there is a relationship between the level of wapiti parentage and non-pregnancy rate at 18 months of age (a proxy for puberty failure) and (3) that minimum liveweight thresholds for puberty increase with increasing levels of wapiti parentage. A total of 4329 18-month-old hinds across four "red" deer farms in southern New Zealand were scanned for pregnancy status. Each hind was assigned a wapiti score (WS) as a subjective assessment of the obviousness of wapiti features. Various body measurements were additionally recorded for each hind. A hair sample was collected for DNA analysis (14 markers) to objectively assign subspecies pedigree (i.e. "Elkmeter") on a subset of 1258 individuals. A total of 506 (11.7%) hinds were not pregnant at 18 months of age with rates varying between 4.1 and 37.3% between farms and years. Mean WS differed significantly between farms and reflected the genetic management policy of each farm. WS was positively correlated to Elkmeter for each farm/year (<0.05) although regression slopes varied significantly. WS was able to be adjusted for these differences to assign a corrected WS (CWS) for all 4329 individuals that estimated the proportion wapiti parentage. Discriminant analysis of morphological variables relative to Elkmeter supported the first hypothesis and showed that shoulder height and body length were good indicators of the degree of wapiti parentage within individuals. This enabled the development of an objective estimate of wapiti parentage (EWP). The actual level of such parentage within herds ranged from <5 to >55%. There was a significant negative association between wapiti parentage and pregnancy, which was strongly influenced by liveweight, supporting the second and third hypotheses. This was manifest as marked displacement of pregnancy probability curves in relation to liveweight between genotype groups, particularly for those groups with >20% wapiti parentage. For example, predicted threshold liveweights required to achieve a 90% pregnancy rate for EWP values that represent 0, 10, 20, 30, 40 and 50% wapiti parentage were 81, 81, 85, 106, 127 and approximately 137 kg, respectively. Within the study herds, the majority of hinds of 0-20% wapiti parentage exceeded the predicted 90% threshold liveweights for their genotype cohort. However, hinds with higher levels of wapiti parentage generally fell below the predicted threshold for their genotype group. The data strongly suggest that under liveweight performance levels measured for red deer, hinds with >20% wapiti parentage are at high risk of puberty failure.

The purpose of this study was to validate noninvasive endocrine monitoring techniques for Pampas deer and to evaluate seasonal changes in testicular steroidogenic activity and their correlation to reproductive behavior, antler cycle and group size. Thus, fecal samples, behavioral data and observations of antler status were collected at monthly intervals during 1 year from free-ranging Pampas deer stags (three radio-collared individuals and 15 random individuals) living in Emas National Park, Brazil (18 degrees S latitude). Fecal steroids were extracted using 80% methanol and steroid concentrations were quantified by a commercial enzyme immunoassay (EIA). Fecal testosterone concentrations peaked in December-January (summer), March (early autumn) and in August-September (winter-spring), with minimal values from April-July. Reproductive behavior had two peaks, the first in December-January, characterized by predominately anogenital sniffing, flehmen, urine sniffing, chasing and mounting behavior, and the second peak in July-September (behavior primarily related to gland marking). There were significant correlations between fecal testosterone and reproductive behavior (r=0.490), and between fecal testosterone and antler phases (r=0.239). Antler casting and regrowth occurred under low testosterone concentrations, whereas velvet shedding was associated with high concentrations of testosterone. We inferred that Pampas deer stags exhibited a seasonal cycle that modulated sexual behavior and the antler cycle, and we concluded that fecal steroid analysis was a practical and reliable non-invasive method for the evaluation of the endocrine status of free-ranging Pampas deer.

The present study aimed to relate feed intake of red deer hinds in the later stages of gestating wapitixred deer crossbred foetuses on dam body condition, gestation length, birth weight and calf growth. Multiparous hinds (N=18) conceiving at known dates to either wapiti (n=12) or red deer (n=6) sires were housed in individual pens from days 150-220 of pregnancy, during which time they were offered either ad libitum access to pelletised rations (n=6 crossbred-bearing hinds [HH] and n=6 red deer-bearing hinds [RH]) or a restricted offer (n=6 crossbred-bearing hinds [HL]) set at 70% of the average ad libitum intake of HH hind in the previous week. Hinds were returned to pasture at day 220 and calving was closely monitored. Liveweights, body condition score (BCS), and lactation score (LS) of hinds were recorded weekly from day 130 of pregnancy until calves were weaned at 12 weeks of age. Calves were tagged and weighed at birth, and subsequently weighed at 7 and 12 weeks of age. HH and RH hinds exhibited similar patterns and levels of MEI/kg0.75, which peaked at 7.8 MJME/kg0.75 at day 220. HL hinds peaked at approximately 5 MJME/kg0.75 and showed significantly lower rates of liveweight gain during pregnancy. Interestingly, both crossbred-bearing groups initiated mammary development in advance of the RH hinds. While there were significant effects of foetal genotype on mean gestation length (239 days versus 234 days for crossbred versus red deer) and mean birth weight (14.5 kg versus 10 kg), the nutritional contrast for gestation length of crossbred-bearing hinds (i.e. HH versus HL) was not significant but approached significance for birth weight (14.5 kg versus 11.9 kg; P=0.06). Regression analysis revealed weak relationships between changes in hind liveweight and gestation length (P>0.05) but a significant relationship with birth weight (P<0.05). However, change in hind BCS was significantly related to both gestation length and birth weight. Crossbred calves reared by HH hinds were 30% heavier at 7 and 12 weeks of age than the red deer calves. However, those reared by HL hinds were significantly lighter than their genotype contemporaries and only marginally heavier than the red deer calves. These results generally contrast with the previous studies on red deer hinds gestating red deer foetuses [Asher, G.W., Mulley, R.C., O'Neill, K.T., Scott, I.C., Jopson, N.B., Littlejohn, R. 2004. Influence of level of nutrition during late pregnancy on reproductive productivity of red deer, (1) Adult and primiparous hinds gestating red deer calves. Anim. Reprod. Sci., in press] and indicate that the genetically determined higher growth requirements of crossbred foetuses may override any mechanism of compensatory control of gestation length at the expense of calf birth weight. Furthermore, there were marked carryover effects of late gestational feeding on crossbred calf growth and their dam's BCS that highlight the high nutritional demands of lactation.

The present study aimed to relate feed intake of red deer hinds during late pregnancy to dam body condition, foetal development and calf growth. Across 3 years, multiparous (n=33) or primiparous (n=18) hinds with known conception dates were housed in individual pens from days 150-220 of pregnancy, during which time they were each offered one of three daily allowances of pelletised rations (11 MJME/kg DM; 16% CP): high (H; ad libitum), medium (M; approximately 30% less; multiparous hinds only) and low (L; approximately 50% less). Restricted intake levels were retrospectively calculated from the mean intake of H hinds in the previous week. Hinds were returned to pasture at day 220 and calving was closely monitored. Liveweights, body condition score (BCS), and lactation score (LS) of hinds were recorded weekly from day 130 of pregnancy until calves were weaned at 12 weeks of age. Calves were tagged and weighed at birth, and subsequently weighed at 7 and 12 weeks of age. Additionally, hinds in the first year of study underwent CT scans on days 150 and 215 of pregnancy to assess compositional changes of the dam and conceptus. Mean daily ad libitum intakes of H hinds increased from 1.8 to 2.0 kg DM (0.6-0.7 MJME/kg0.75) at around day 150 to 2.8-3.2 kg DM (0.8-0.9 MJME/kg0.75) by day 220. Those of M and L hinds peaked at 1.8 and 1.6 kg DM, respectively, by day 220. This was reflected in significant treatment effects on liveweight gain and change in BCS and LS by the time of calving. CT scans indicated a significant treatment effect by day 215 on the mass of hind tissues (fat and lean) and a non-significant trend on conceptus/foetal weights. Despite apparent differences in foetal growth trajectories, there were no discernable treatment effects on sex-adjusted birth weights. However, there was an unexpectedly wide spread in calving dates that reflected considerable variation in gestation length. Furthermore, gestation length was negatively correlated with change in hind liveweight (but not BCS) between days 150 and 220 of pregnancy for all groups of hinds (P<0.05). Of three neonatal calf mortalities, none were related to overweight (dystocia) or underweight (non-viability) calves. Subsequent growth rates (g/day) of surviving calves did not reflect prior treatment of their dams, although variation in birth date influenced weights on specific dates. It is concluded from this study that while variation in nutrition to hinds during the last trimester may strongly influence foetal development, under conditions of modest feed imbalance, variation in gestation length compensates to ensure optimisation of birth weight.

Winter severity is a primary factor influencing deer survival and reproduction in northern climates. Prolonged, harsh winters can adversely affect body condition of does, resulting in depressed morphologic development of neonates. In this study, we captured 59 white-tailed deer (Odocoileus virginianus) neonates (28 in 2001 and 31 in 2002), following two distinctly different winters, one severe and the other historically mild. Vaginal implant transmitters allowed exact age to be determined for 73% of the neonates; new hoof growth was used to estimate age (days) of the other 27%. Birthdate and morphologic measurements of neonates (i.e., birth mass, new hoof growth, hoof length) were compared by sex and capture year. For known-age neonates (n=43), there was a year-by-sex interaction effect (P=0.01) on birthdate, being later for females during spring 2001 compared with 2002, which was consistent with a significant (P=0.03) year-by-sex interaction for total hoof length (22.3 mm [SE=0.9] and 20.3 [SE=0.8] for females and males in 2001; 19.9 [SE=1.0] and 22.1 [SE=1.0] for females and males in 2002). Interestingly, there was no effect of year on birth mass or birthdate of known-age neonates. A year-by-sex interaction (P=0.04) was determined for birthdates of estimated age (5 yr old were born later (P<0.01) than fawns born to dams

Observations on individually marked fallow deer (Dama dama) in central Italy were performed over 2 years in order to analyse time budgets of four age and sex classes. The aim was to test whether feeding activity was influenced by mating activity, forage quality or physiological constraints during the rut. Only adult males (bucks) completely ceased feeding during the rutting season, well before the actual start of mating behaviour and concurrently with the phenomenon of scent-urination, and spending most of their daily time completely inactive. All other age and sex classes were unaffected in their feeding behaviour by the rutting season. Indeed, females and young males showed a marked increase in grazing in response to an improvement in forage quality from summer to autumn. These results seem to confirm the hypothesis that hypophagia, displayed only by bucks, may be of no adaptive value in itself. On the other hand, it may be a by-product of other physiological processes occurring during the rut, inducing scent-urination, which plays an important role in intraspecific recognition and sexual attraction.