Environmental fluctuations force animals to adjust glucocorticoids (GCs) secretion and release to current conditions. GCs are a widely used proxy of an individual stress level. While short‐term ...elevation in GCs is arguably beneficial for fitness components, previous studies have documented that the relationship between long‐term baseline GCs elevation and fitness components can vary according to ecological and individual factors and according to the life‐history of the species studied. Using longitudinal data on roe deer Capreolus capreolus from two populations facing markedly different environmental contexts, we tested whether baseline GC levels negatively correlate with body mass – a trait positively associated with demographic individual performance – on the short‐ to long‐term. In support, higher baseline GC concentrations were associated to lighter body mass, both measured during the same capture event, in adults of both populations. Overall, we showed that despite the marked environmental and demographic differences between populations and despite the between‐sex differences in life history (i.e. reproductive tactics), the relationship between body mass and GCs is consistent across environmental contexts, but might differ according to the life history stage of an individual. This work opens promising perspectives to further explore the relationship between GC and fitness‐related traits according to life history stages in free‐ranging mammals across seasonal and environmental contexts. The timing and context‐dependence of GC levels highlight the complexity of studying stress responses in the wild.
The aim of this study was to determine the change in the value of
morpho-metric parameters of antlers and the total trophy score in relation
to the age of roe deer (Capreolus capreolus L.). The study ...was conducted on
228 roe deer trophies from the "Barajevska reka" hunting ground in Serbia,
aged one to seven years. From the second to the fourth year, the growth of
antlers was the most intense, and the differences compared to one year old
animals were significant (P <0.001). The highest average length of the
branches was monitored in six years old animals (22.4 ? 2.05 cm), with
significant differences (P <0.001) compared to younger animals, except for
the three years old animals (P>0.05). From the second to the fifth year, a
gradual increase in antler weight (from 192.2 ? 30.41 g to 221.9 ? 61.86 g)
and antler volume (from 74 cm3 to 90 cm3) was observed, with the highest
values of antler weight (291.8 ? 58.43 g and 319.1 ? 98.89 g, respectively)
and antler volume (123.8 cm3 and 121.2 cm3) in six and seven year old
animals. Overall trophy scores increased from year one to year seven (42.6 ?
7.86 vs 97.4 ? 27.40), with differences in trophy scores for animals aged
six and seven years significantly greater than for animals aged one to five
years (P <0.001). The highest quality antlers have six and seven year olds,
at which time their hunting should be conducted.
Abstract
As climate change intensifies and demand for timber rises, forest disturbances are increasing. Disturbances in forests cause an abrupt loss in canopy cover and increase resource availability ...on the ground, which can have manifold effects on the habitat quality of forest‐dwelling species. One pathway through which disturbances influence habitat quality is by creating edges within forests. Disturbance‐created edges differ from edges to other land cover types in that they are transient, that is, they persist only for a limited period of time until canopy closes again. While the effects of permanent edges are well‐studied in ecology, the role of transient edges remains largely unclear.
Here, we investigated whether edges caused by forest disturbances affect the individual fitness of two contrasting ungulates by examining the body mass of 378,602 roe deer (
Capreolus capreolus
) and Alpine chamois (
Rupicapra rupicapra rupicapra
) yearlings collected between 1992 and 2019 in the Eastern Alps.
Transient edges had a significant positive effect on the body mass of both species. The effect size was larger for chamois than for roe deer, with yearling body mass increasing by up to 0.18 kg in female chamois for each 10 m ha
−1
increase in edge density. Elevation modulated the effect of edges on chamois body mass, with a weaker effect of transient edges in high‐elevation forests that are naturally more open. The effect duration of transient edges was longer for roe deer than for chamois, lasting for up to 9 years post‐disturbance.
The body mass effect of transient edges created by forest disturbances was an order of magnitude stronger than the effect of permanent edges between forests and other land cover types.
Synthesis and applications
: Increasing forest disturbances under climate change could improve the fitness of ungulates, potentially affecting forest recovery through browsing. Managers and hunting authorities should consider the effect of disturbances and dynamically changing carrying capacity of forest landscapes more explicitly when making decisions regarding habitat management and hunting policies. Such a dynamic perspective is an important element in balancing vital ungulate populations and healthy forest ecosystems.
We describe a bilateral craniodorsal dislocation of the hip joint in a free-ranging young roe buck and the associated pathological changes in the ossa coxae and femora of the animal. The highly ...symmetrical dislocation, which is considered to have developed secondary to hip dysplasia, caused the formation of two false acetabula that each consist of several, partially fused bone portions. The femora exhibit symmetrical outgrowths that extend from the greater trochanter along the intertrochanteric crest to the lesser trochanter. Formation of these outgrowths is attributed to abnormal traction at muscle attachment sites due to the displacement of the femora. On radiographic examination, both femora show signs of avascular necrosis in their head regions and of fatty marrow necrosis in their shafts, which is attributed to the damage of the arterial blood supply of the femora that was associated with the dislocation. The fact that, according to the hunter who shot the buck, the animal’s locomotion was inconspicuous suggests that the false hip joints functioned quite well, thereby demonstrating a remarkable capacity of the musculoskeletal system for functional recovery.
The toxicity of lead has been known for a long time, and no safe uptake level can be derived for humans. Consumers' intake via food should therefore be kept as low as possible. Game meat can contain ...elevated levels of lead due to the use of lead ammunition for hunting. A risk assessment conducted in 2010 by the German Federal Institute for Risk Assessment including various consumption scenarios revealed a possible health risk for extreme consumers of game meat hunted with lead ammunition (i.e. hunters and members of hunters' households). Babies, infants, children and women of childbearing age were identified as vulnerable group with regards to the developmental neurotoxicity of lead. It was noted, that a sound data base was required in order to refine the assessment. Therefore, the research project "Safety of game meat obtained through hunting" (LEMISI) has been conducted in Germany, with the aims of determining the concentrations of lead (as well as of copper and zinc) brought into the edible parts of game meat (roe deer (Capreolus capreolus) and wild boar (Sus scrofa)) due to using either lead or non-lead hunting ammunition, whilst concurrently taking geogenic (i.e. "background") levels of lead into account. Compared to non-lead ammunition, lead ammunition significantly increased lead concentrations in the game meat. The use of both lead and non-lead ammunition deposited copper and zinc in the edible parts of game meat, and the concentrations were in the range of those detected regularly in meat of farm animals. For the average consumer of game meat in Germany the additional uptake of lead only makes a minor contribution to the average alimentary lead exposure. However, for consumers from hunters' households the resulting uptake of lead-due to lead ammunition-can be several times higher than the average alimentary lead exposure. Non-lead bullets in combination with suitable game meat hygienic measures are therefore recommended in order to ensure "state of the art consumer health protection".
Although several studies have focused on the influence of moonlight on deer–vehicle collisions, findings have been inconsistent. This may be due to neglect of the effects of cloud cover, a major ...impediment to moon illumination and circannual variation in both deer and human activity.
We assessed how median cloud cover interacted with the illuminated fraction of the moon in affecting daily roe deer (Capreolus capreolus) roadkill in Slovenia (Central Europe). Data included nationwide roadkill (n = 49,259), collected between 2010 and 2019 by hunters, as required by law.
Roadkill peaked under medium to high cloud cover and decreased during nights with low or extremely high cloudiness. This pattern was more pronounced on nights with a full moon. However, the effects of moon illumination and cloud cover had a lower predictive potential than circannual variation, as collisions clearly peaked in April/May, July and August/September.
Our results suggest that moonlight could influence roe deer movements through compensatory foraging. However, on nights with a full moon, collisions could also be affected by weather. On bright nights, roe deer might be less active due to increased human presence and sustained vehicular traffic. Then, with medium to high cloud cover and also rainfall, human presence in the environment may be low enough to increase deer movements, but vehicular traffic can still be intermediate, maximizing the risk of collisions. Finally, with overcast skies, widespread rainfall can reduce both traffic volume and human outdoor activity, decreasing the risk of collisions.
Moon illumination may indeed affect wildlife–vehicle collisions and roadkill, but its effects should be quantified as a function of cloud cover. Moreover, to make studies truly comparable, research about wildlife–vehicle collisions should also account for time of the year.
Policy implications. Because collisions with roe deer peak at particular periods of the year, signs should be installed seasonally. By doing so, they would warn drivers about the risk, improve drivers' awareness and increase their safety. Moreover, as collisions also increase on nights with a full moon and overcast skies, interactive warning signs that are activated by ground illumination should also be useful.
Izvleček
V preteklosti je bil vpliv mesečine na trke vozil s prostoživečimi prežvekovalci (predstavniki družine jelenov) večkrat proučevan, vendar so bile ugotovitve nekonsistentne. To je lahko posledica zanemarjanja učinka oblačnosti, ki pomembno vpliva na osvetlitev zaradi lune, in sezonske variabilnosti v aktivnosti tako predstavnikov družine jelenov kot tudi ljudi.
Modelirali smo, kako je oblačnost skupaj z lunarno fazo vplivala na povprečni dnevni povoz evropske srne/srnjadi (Capreolus capreolus) v Sloveniji (srednja Evropa). Podatki so vključevali celokupen povoz (tj. smrtnost na cestah) srnjadi v vseh loviščih Slovenije v obdobju 2010–2019 (n = 49.259), ki so ga glede na zakonsko obvezo sistematično registrirali lovci kot dobro usposobljeni ljubiteljski (državljanski) znanstveniki.
Povoz srnjadi je kulminiral pri srednji do izraziti oblačnosti, zmanjšal pa se je v nočeh z (izjemno) majhno oblačnostjo. Ta vzorec je bil bolj izrazit v nočeh s polno luno. Vendar so imeli učinki lunine osvetlitve in oblačnosti bistveno manjši napovedni potencial kot sezonska variabilnost, saj je imel povoz izrazite viške v treh obdobjih, tj. aprila/maja, julija in avgusta/septembra.
Rezultati kažejo, da bi lahko mesečina vplivala na prostorsko vedenje srnjadi preko povečane aktivnosti (npr. kompenzacijskega prehranjevanja). Vendar na pogostnost trkov ob polni luni vpliva tudi vreme. V jasnih nočeh je morda srnjad manj aktivna zaradi večje prisotnosti ljudi v naravi in/ali povečanega prometa. V delno oblačnih in zmerno deževnih nočeh je prisotnost ljudi v okolju verjetno manjša, kar lahko povzroči večjo aktivnost/premike živali, a je tedaj gostota prometa še vedno tako velika, da povečuje tveganje za trke. Nasprotno pa lahko v povsem oblačnih nočeh intenzivne padavine zmanjšajo gostoto prometa in aktivnosti ljudi v naravi, posledično pa tudi tveganje za trke.
Lunarna faza oz. osvetlitev lahko vpliva na pogostnost trkov s prostoživečimi živalmi oz. smrtnost le‐teh na cestah, vendar pa je treba njene učinke količinsko opredeliti v odvisnosti od oblačnosti. Da bi bile različne študije medsebojno resnično primerljive, bi morale raziskave o trkih s prostoživečimi živalmi upoštevati tudi sezonsko variabilnost v številu trkov oz. bi morale temeljiti na analizi časovnih vrst.
Pomen za implikacijo. Trki s srnjadjo so najpogostejši v točno določenih obdobjih leta, zato bi lahko postavitev sezonske opozorilne signalizacije, ki bi voznike opozarjala na tveganje za nalet srnjadi, izboljšala pozornost voznikov in povečala njihovo varnost. Tveganje za trke se poveča v nočeh s polno luno in oblačnim nebom, zato bi lahko bila koristna tudi namestitev interaktivnih opozorilnih znakov, ki bi se aktivirali glede na stopnjo osvetlitve tal.
Because collisions with roe deer peak at particular periods of the year, signs should be installed seasonally. By doing so, they would warn drivers about the risk, improve drivers' awareness and increase their safety. Moreover, as collisions also increase on nights with a full moon and overcast skies, interactive warning signs that are activated by ground illumination should also be useful.
The use of species detection rates gathered from motion‐sensitive cameras as relative abundance indices (RAIs) could be a cost‐effective tool to monitor wildlife populations; however, validations ...based on comparisons with reference methods are necessary. We considered 3 ungulates, wild boar (Sus scrofa), roe deer (Capreolus capreolus), and fallow deer (Dama dama), and compared 2 different RAIs with independent indices of density obtained through feces counts across 3 summers (2019–2021) in a protected area of central Italy. We estimated the number of detections per day (RAIevents), and the number of individuals per day (RAIindividuals) from remote camera videos. Both indices were correlated with density estimates, yet only RAIindividuals correctly ranked interspecific densities. Values of RAIevents for the most abundant and gregarious ungulate (i.e., wild boar) were biased low and were lower than those of fallow deer. The uncertainty of RAIs was acceptable for the 2 most abundant study species (CVs ≤ 25%) but was greater for roe deer. At the intra‐specific level, density estimates and RAIs showed comparable but slight inter‐annual variation. Our results support the use of RAIs derived from motion‐sensitive cameras as a promising and cost‐effective tool to monitor ungulate populations, and researchers should incorporate group size into monitoring. We advocate the necessity of field tests based on comparison with locally reliable reference methods to validate the use of motion‐sensitive cameras.
Cameras could be used to estimate relative abundance indices (RAIs) as cost‐effective tools to monitor wildlife populations, but validation tests based on comparisons with reference methods are necessary. For 3 ungulate species, we found that RAIs based on species' group size correlated with independent estimates better than traditional RAIs based on the raw count of species' detections. For gregarious species, RAIs based on camera detections should consider group size.
In Europe, genetically distinct ecotypes of the tick-vectored bacterium Anaplasma phagocytophilum circulate among mammals in three discrete enzootic cycles. To date, potential ecological factors that ...contributed to the emergence of these divergent ecotypes have been poorly studied. Here, we show that the ecotype that predominantly infects roe deer (Capreolus capreolus) is evolutionarily derived. Its divergence from a host generalist ancestor occurred after the last glacial maximum as mammal populations, including roe deer, recolonized the European mainland from southern refugia. We also provide evidence that this host specialist ecotype's effective population size (
) has tracked changes in the population of its roe deer host. Specifically, both host and bacterium have undergone substantial increases in
over the past 1,500 years. In contrast, we show that while it appears to have undergone a major population expansion starting ~3,500 years ago, in the past 500 years, the contemporary host generalist ecotype has experienced a substantial reduction in genetic diversity levels, possibly as a result of reduced opportunities for transmission between competent hosts.
The findings of this study reveal specific events important for the evolution of host specialization in a naturally occurring, obligately intracellular bacterial pathogen. Specifically, they show that host range shifts and the emergence of host specialization may occur during periods of population growth in a generalist ancestor. Our results also demonstrate the close correlation between demographic patterns in host and pathogen for a specialist system. These findings have important relevance for understanding the evolution of host range diversity. They may inform future work on host range dynamics, and they provide insights for understanding the emergence of pathogens that have human and veterinary health implications.
Radiocarbon dates for the ancient drawings in the Chauvet-Pont d’Arc Cave revealed ages much older than expected. These early ages and nature of this Paleolithic art make this United Nations ...Educational, Scientific and Cultural Organization (UNESCO) site indisputably unique. A large, multidisciplinary dating program has recently mapped the anthropological evolution associated with the cave. More than 350 dates (by 14C, U-Th, TL and 36Cl)were obtained over the last 15 y. They include 259 radiocarbon dates, mainly related to the rock art and human activity in the cave. We present heremore than 80 previously unpublished dates. All of the dates were integrated into a high-precision Bayesian model based on archaeological evidence to securely reconstruct the complete history of the Chauvet-Pont d’Arc Cave on an absolute timescale. It shows that there were two distinct periods of human activity in the cave, one from 37 to 33,500 y ago, and the other from 31 to 28,000 y ago. Cave bears also took refuge in the cave until 33,000 y ago.
Among ungulates, capital breeding males, especially in highly dimorphic species, support higher reproductive costs than females. Roe deer, a relatively monomorphic species, is defined as an ‘income ...breeder’, using a concurrent intake of energy from forage to pay for a reproductive attempt. In a Northern Apennines (Arezzo province, Tuscany, Central Italy) population, we detected sexual dimorphism in adult roe deer according to average body mass (males 11% heavier than females), mandible size (male mandibles are 2% longer than female ones), and tooth measurements (first lower molar 10% higher and mandible cheek teeth row 4% longer in males than in females, providing males with a larger surface for chewing). In our study, body mass and body condition of roe deer males decreased with increasing tooth wear as in females. However, males started losing weight at a lower tooth wear level than females; after losing about 15% (~3.2 kg) of body mass they had greater probability of death than females. For low‐dimorphic species like roe deer, these findings raise new considerations about the role of sexual dimorphism in feed intake efficiency.
In a Northern Apennines (Italy) population, we detected sexual dimorphism in adult roe deer according to body mass, mandible size, and tooth measurements. Moreover, we evaluated the role of tooth wear in causing senescence. Body mass and body condition of roe deer males decreased with increasing tooth wear. However, once they reached tooth wear values half of those of females, they were no longer able to support the intake of a necessary amount of energy, suggesting that chewing capacity in males has been compromised. Males also wear down a larger proportion of teeth than females over their lifetime; after losing about 15% of body mass, they have a greater probability of death than females. These data open up new questions for low‐dimorphic species like roe deer, that is, exploring sexual dimorphism in relation to feed intake efficiency among different populations.
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