Microhistology analyses are well-supported techniques useful for studying herbivore diet composition, but they involve the correct identification and validated relative quantification of the plant species consumed, as well as the knowledge of possible biases inherent to methods. We analyzed two methods for quantifying the relative frequency of plant cuticles using an experimental procedure from laboratory- prepared samples. The factors affecting the precision of quantification were analyzed, the minimum sampling effort to detect all plants in the experimental mixture was estimated and the practical application on a complex real sample discussed, in order to describe a simple, standardized, and reliable procedure for studies of herbivore diet composition in Mediterranean ecosystems. Ten random mixtures were prepared with combinations of 40 known plant species, in different number and dry weight percentages. A total of 100 microscopic fields, distributed across 5 slides per sample, were analyzed using both quantification methods. Statistical analysis concluded that the two methods differed significantly. Higher precision was achieved with the method based on annotating the presence/absence of each species in each microscopic field, instead of the total number of times each plant was detected in each field. The important predictors of accuracy were the complexity of the sample and the proportion of plant material in the mixtures. The number of slides and microscopic fields did not significantly impact the quantification results, and no additional species were identified beyond 25 fields in the most complex samples. Due to its greater reliability, shorter analysis time, and reduced visual effort, the first method proved to be more efficient. This method is validated and useful in diet studies of overabundant populations of deer and extensive and transhumant livestock to evaluate the impacts of herbivores on ecosystems and generate sustainable management criteria in the use of pastures toward environmental and economic sustainability. (c) 2024 The Society for Range Management. Published by Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Numerous studies focus on creating 3D-models of biological elements for geometric evaluation using CAD tools. A crucial aspect is to obtain accurate geometrical data that is easy to obtain and cost-effective for analysis. The main objective is to evaluate the geometrical accuracy of 3D-models obtained with three graphical techniques of three-dimensional geometrical documentation that characterise the fallow deer antlers in an accurate 3D-model, which is used as input data in biological analyses estimating hunting quality, asymmetry and volume. Three technologies are evaluated: structured light scanning, multi-image photogrammetry (SfM), Structure from Motion, and spatial photogrammetric restitution using two photographs in a CAD system. The geometric accuracy of the 3D-models obtained and the deviation between relevant points of the antler structure, in the main beam, in the main tines and palm, are estimated. Subsequently, the suitability of each 3D-model is studied according to the type of biological application for which it is intended. Based on the results, solid and axial 3D-models, the applicability of the three techniques for the study of biological parameters such as hunting quality, asymmetry and volume is discussed. It concludes on the most appropriate procedure to define the digital characterisation of the antler, depending on the type of biological study to be carried out in order to obtain accurate results. Characterising a geometrically complex structure such as the fallow deer antler in a 3D-model quickly and accurately can help to quantify various biomarkers in populations of specimens, making it possible to infer internal and external influencing factors.

In the field of biology, the ’biomarkers’ of the different animal species are of great relevance, as well as the relationships between them and the quality of the habitat. A study was proposed, analysing the antlers of the Iberian deer, to measure the bilateral asymmetry of its branches. The antlers are characterised in a 3D CAD model of their axial structure obtained via photogrammetric restitution from two photographs. This method quantifies the global and partial asymmetries of the antler’s structural features. The research evaluated 48 deer antlers from hunting days and taxidermy workshops. To quantify asymmetries, the measurements required are the same as those considered to assess the hunting quality of antlers. Bilateral deviations are estimated for each structural trait and the whole antler. Preliminary results showed a convergence between the values of global asymmetry and hunting quality. The methodology proved to be fast, inexpensive, and easy to implement, which facilitates its use in future asymmetry studies of other biological elements of animal or plant origin. It is only necessary that the starting data, which is the bilateral axial structure of the analysed element, is characterised in a 3D model.

The genus Cistus plays a crucial role in the Mediterranean ecosystems. However, studies on microhistological characters of its leaves are scarce, resulting in a knowledge gap. We focused here on all Cistus species in the eastern Sierra Morena, southern Iberian Peninsula: C. albidus, C. crispus, C. ladanifer, C. laurifolius, C. monspeliensis, C. populifolius and C. salviifolius, because these species are present in the diet of ruminant herbivores such as deer. Our study involved analysing, characterizing, and comparing trichomes, stomata and epidermal cells, with a total of 17 variables analysed. The results confirm the distinction of Cistus species based on microhistological characteristics. Understanding these structures facilitates taxonomic classification and analysis of wild ungulate diet and habitat selection using light microscopy. We generate a helpful resource for future micro-histological analysis studies applied to wild ungulate diets determination, botany, conservation biology and resources management.

Understanding and tracking the complexities of animal movement patterns is of paramount importance in wildlife management, conservation efforts, and the sustainable use of natural resources. An infinite number of factors influence the movement path of animals within their respective habitats, including: the structure of the habitat, the availability of resources, the presence of natural predators, social memory, the topographic attributes of the environment, etc. Numerous studies have attempted to delineate the spatial boundaries of animal habitats by elucidating the complexities of their movement dynamics. These investigations have highlighted the profound impact of factors such as environmental topography and the presence of natural impediments and other anthropogenic structures on animal mobility, but very few have analyzed topographic factors at a fine three-dimensional spatial scale. This research focuses on a novel methodology for identifying animal trajectories at a fine scale and evaluating the influence of topographic factors on these trajectories, specifically of deer herds in southern Spain. To understand movement patterns, transects recorded in the field due to continued use by deer are analyzed. Topographical information was obtained in two steps: first with a graphical analysis of orthophotos for the incorporation of the sufficient data set. Secondly, the veracity of this data was verified using Global Positioning System (GPS) tracking technology. The integration of data from multiple sources with Geographic Information Systems (GIS) allowed the analysis to be automated. Next a statistical linear regression model, based on both the ascent and descent lengths and the total length of the path traveled, was designed to infer the trajectories between two designated points within the study area. Using topographical variables obtained in the study environment, such as the slope, the elevation difference (cumulative vertical distance), and the 3D length of the transect paths, the influence of these variables on the movement decisions of animals within their habitat is established in order to facilitate their subsequent prediction. Analytical tests of the trajectories have shown that the movement behavior of cervids is predictable. The results demonstrate the usefulness of the methodology presented which, by providing and collect valuable topographic information on movement and transit areas, can guide sustainable management practices for deer populations and their habitats.

In this paper, we describe for the first time a finding of fetal maceration in a wild Iberian hind (Cervus elaphus hispanicus, Erxleben, 1777). Fetal maceration seems to occur in fetuses that have died and have not been expelled due to insufficient dilation of the cervix, but which allows the penetration and ascent of germs through the birth canal. It can occur at any stage of gestation, although it is more common in mid to late gestation. In our case, the stage of development and skeleton ossification and the degree of eruption of the premolar teeth of the mandible allow us to infer that the death of the fetus and the process of maceration occurred from the end of gestation. This discovery occurred during the butchering of a female hunted as part of the management programme to reduce the abundance of the population in Quintos de Mora, Spain. Although the female was in good body condition, she was selected because she had no calf and had an aged appearance. We describe the case in detail and draw attention to the interest of recording the rates of pregnancy losses and abortions in studies of fitness and population dynamics in wildlife.

Most European rewilding initiatives are based on the recovery of large herbivores, particularly European bison Bison bonasus, aiming at restoring ecosystem processes and increase trophic complexity. The growing support for the release of bison as a wild species, and change its legal status, in Spain, as an ecological analogue of the extinct steppe bison Bison priscus, makes it an excellent example to reflect the limits of a rewilding biogeographically advisable. We discuss if this initiative could be justified from ecological, biogeographical, ethical, and legal reasons. Besides remarkable taxonomic and functional differences between both bison species, the Mediterranean environment, under the present and future climatic scenarios, does not suit the European bison. Furthermore, there is no evidence to support the presumption that the European bison was ever present in the Iberian Peninsula, with legal implications. We expect that our approach will be inspirational for similar assessments on rewilding initiatives globally.

The use of tracking collars implemented with Global Positioning System (GPS) has allowed increasingly complex analyses of the movement and space use of tagged animals. Fundamental to these studies is the setting of parameters related to the technology itself. In this study we assessed the effect of the fix interval on certain ecological variables used to describe behavior, animal movement, home range size and habitat use through parameters such as path length, sinuosity, core area or minimum convex polygon. The aim of the study was to select the most reliable time interval in the study area in the northwest province of Jae & PRIME;n (Spain) for a subsequent use of the collars on wild ungulates. For this purpose, we designed and developed static and moving tests for evaluating 6 GNSS collars, one of them improved by using multi-costellation and multifrequency module, programmed with 5 different time intervals. The kinematic results suggest using caution when programming the collars since differences in the sampling interval leads to important differences in the real trajectories. Movement descriptors varied according to time interval, being longest and more winding with the shortest intervals. Similarly, home range approximations were closer to reality as more fixes were obtained. We progressively underestimated the use of the central core zone and the distance reached by the individual as we increased the time interval. However, there is a trade-off between time, autocorrelation and battery expenditure that is almost the only limiting factor. The experimental results show that a fixing interval of 30 min is an optimal and reliable value to studies focused on the estimation of path length or home range estimation. This value also involves a trade-off between high-resolution data and battery life.

Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological adaptations that allow them to penetrate the ground and live underground, through a system of galleries and permanent chambers that they build themselves. Among the morphological adaptations in this group, those of the skull stand out as it serves as the main excavation tool. Four basic skull shapes are recognized: rounded, keeled, shovel-shaped, and spade-shaped. The skull of L. microcephalum belongs to this last type, which is considered the most specialized. The species inhabits soils that are highly compacted and difficult to penetrate. Among the species of Leposternon present in South America, L. microcephalum has the widest distribution, being found in all Brazilian biomes and neighboring countries such as Bolivia, Argentina, Paraguay, and Uruguay. The analysis of the skull of this species was carried out using three-dimensional geometric morphometrics (3D-GMM), a technique that allows comparative analysis, through robust statistical methods, of shape and its variations, using Cartesian coordinate data from a configuration of homologous landmarks. The technique allows the size and shape components of a structure to be analyzed separately. From an ontogenetic point of view, this methodology had also been used to investigate variations in Cynisca leucura, a member of the Amphisbaenidae with a rounded head. Our hypothesis is that the patterns of morphological differentiation in the skull, mainly in the intermediate and occipital regions, are similar in different Amphisbaenia species. Therefore, the objective of this study was to analyze cranial morphological variations in an ontogenetic series of L. microcephalum using 3D-GMM. Computed Tomographic scans of 13 specimens were analyzed: juveniles (N = 8) and adults (N = 5), based on 20 landmarks that characterize the skull. Principal components and regression analyses between shape (dependent variable) and size (independent variable) showed a clear difference between the cranial morphological pattern of juvenile individuals and that of adults. For instance, young specimens tend to have a dorsoventrally tall neurocranium, with the tip of the snout more anteriorly oriented and its dorsal border subtly curved. Dorsally, the parietal region is thicker and smoothly dome-shaped in juveniles. As in C. leucura, the variation was strongly correlated with the size change from juvenile to adult, indicating a dominant role for ontogenetic allometry in determining skull shape.

Deer hunting has traditionally had great relevance due to the diversity of resources obtained from it, such as meat. Our aim has been to analyse the total post-mortem weight, dressed carcass weight and carcass yield, as well as their variations as a function of years, sex, age and hunting season (autumn vs. winter). Also, predictive equations for carcass weight from total weight were performed. A total of 947 red deer (Cervus elaphus hispanicus) of both sexes, hunted from 1989 to 1993 in the Quintos de Mora National Reserve, Spain, were analysed. Seasonal and interannual differences were detected in all weight measures and carcass yield, conditioned by sex, age and climatic factors such as temperature. In general, to obtain a higher meat yield deer extractions should be carried out in autumn. In addition, carcass weight variation (measured on cold carcasses dressed without head and feet, keeping skin, lateral diaphragm portions, fat deposits and legs) can be considered a good indicator of body condition that integrates seasonal nutritional gains and/or losses and long-term nutritional legacies. This index provides information on the animal's natural history and ecological environment conditions, making its standardized record an essential tool for monitoring wild game populations.

Natural events over time, and human interventions, influence the genetic structure of species. The red deer (Cervus elaphus) is widely distributed in Europe, with a large-scale genetic structure largely determined by Pleistocene climatic oscillations. The Iberian Peninsula acted as one of the main glacial refuges for many species; a particular red deer lineage remains on the peninsula and is subjected to special conservation policies. The mountain range of the Pyrenees might be a contact zone where Iberian red deer (Cervus elaphus hispanicus) could hybridize with other central European genetic lineages. In the late twentieth century, the natural distribution areas of red deer on both sides of the Pyrenees became closer because of restocking from central Iberia to areas south of the Pyrenees and from French populations to areas north of the Pyrenees. We analyzed the genetic structure of red deer populations in the Pyrenees to investigate the underlying processes of population contact and hybridization. The analysis of microsatellite genotypes showed 2 genetic clusters. One of these clusters associated with Iberian red deer, whereas the other presented European non-Iberian genetic composition. Migration and hybridization events occurred between both genetic clusters, mostly in the eastern part of the sampling area. The Pyrenees is currently a secondary contact zone caused by anthropogenic translocations, and a risky hybrid belt for red deer genetic conservation.

The present research aims to determine the age at which red deer (Cervus elaphus) specimens died by examining their upper dentition. We analyzed eighty free-ranging individuals from southern Spain to establish a reference database for age calculation. The age of these individuals was identified by the mandibular teeth inferred from their known death years and the maxillary teeth were evaluated relative to them. As a result, we have provided three non-destructive methods: a description of the eruption sequence and dental replacement, a referential code for occlusal wear stages, and a regression analysis considering the height of the cusps in both upper and lower dentition. These methods offer the possibility of estimating the age at which the animals died and categorizing them into specific age groups. To evaluate the practicality of this method, we applied it to the Middle Paleolithic archaeological site of Abric Romaní. All the proposed methods allow us to approximate the age at death of red deer individuals. The most accurate results, whenever feasible, are obtained by combining these different methods. This study facilitates the inclusion of upper dentition fossils that have traditionally been omitted from the analysis in archaeological sites, allowing a better adjustment of the quantitative methods used to calculate the number of skeletal elements and the number of individuals. This, in turn, enables a more accurate construction of the anatomical and mortality profiles.

The use of global navigation satellite systems (GNSS) technology within the fields of ecology and biology has increased over recent years. With Global Positioning System, GLObalnaya NAvigatsionnaya Sputnikovaya Sistema, Galileo, and BeiDou systems fully deployed, >140 navigation satellites are currently available for navigation and high precision positioning applications. The technological improvements in GNSS devices, mainly due to the multi-frequency capability, reduce signal acquisition time and increase the reliability, the continuity, and the accuracy of the estimated position, especially in complex environments like forests or areas with a steep topography. This study aims to test experimentally the influence of multi-constellation multi-frequency modules on the performance of the GNSS collars used to monitor wildlife. We applied static and kinematic tests designed to assess and compare the performance of GNSS collars equipped with a single-frequency versus a multi-frequency chipset. We evaluated the availability and continuity of solutions, number of satellites used, dilution of precision, precision, accuracy, and repeatability of these quality parameters for GNSS devices in southeastern Spain from February 2021 to June 2022. The results confirmed that the multi-constellation multi-frequency GNSS collar showed a stable and good performance in terms of the number of satellites used (>10), horizontal dilution of precision (<1.3), fix success rate (100%), mean location error (<1.5 m), and circular error probability (CEP), which was better by approximately one order of magnitude than the single-frequency collar (1-10 m). The use of reliable and accurate GNSS devices will expand our knowledge of animal behavior and the interactions between species. Multi-frequency GNSS collars allow collection of accurate locations, providing fine-scale information about animal behavior (e.g., feeding strategies, competition for resources), whereas the single-frequency GNSS collars can used for broad-scale studies (e.g., home ranges, habitat use).

Extraction and mineral processing, as well as the waste generated by old abandoned mining sites, are the main sources of contamination of water bodies and lands by potentially toxic elements (PTEs). The common carp (Cyprinus carpio Linnaeus 1758) has been reported to be a good ecological indicator of environmental pollution in water bodies. Hence, we evaluated the concentration of eleven PTEs (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in different tissues of common carp in two reservoirs of the province of Jaén, southern Spain: El Tranco de Beas (S1) and La Fernandina (S2). We also assessed the concentration of PTEs in water and sediment samples. We used inductively coupled plasma mass spectrometry for all the collected samples. We found high concentrations of As and Fe in water in the S2 reservoir, above the maximum limits allowed by the sanitary criteria in Spain; however, the analysis of sediments indicated low ecological risk in S1 and moderate ecological risk for As in S2. The concentration of PTEs in common carp was higher in the S2 reservoir, exceeding the permissible limits in the case of As, Cd, Pb, and Zn. As and Cd showed higher concentrations in the kidney; Cu, Fe, and Zn showed higher concentrations in the liver; and Pb and Mn presented higher concentrations in the gill and gill bone. There was a good correlation between the concentrations found in water/sediment samples and those in common carp, corroborating its usefulness as a good ecological indicator, allowing the detection of environmental pollution and inferring previous or current anthropogenic activities such as mining.

In the area of zoology, it is of great interest to determine the degree of asymmetry existing in the different animal structures in order to establish it as a variable (biomarker). In this study, a new methodology is proposed for obtaining this variable 'Asymmetry Index'. Forty-eight Iberian red deer antlers (Cervus elaphus hispanicus) from hunting reserves in the province of Jaen (Spain) have been used. The degree of asymmetry of their antlers between homologous points considered in the two right and left sides of each antler was obtained. The methodology is applied within a parametric Computer-Aided Design system from the photogrammetric restitution of the antler from two photographs. The procedure compares the degree of asymmetry in which the points of each of the right and left sides of the antler are found by means of lengths and angles with respect to an established reference plane based on the geometry of the specimen's skull. As a result of the study, it has been observed that the Asymmetry Index obtained is lower in those specimens that have a high score in their hunting valuation, so it is considered that this factor can be taken into account as an objective and quantifiable indicator (biomarker).

Teeth root morphology and integrity are essential to provide appropriate attachment, allowing for continuous and functional movement, with implications for adequate food processing, animal performance, and longevity. We studied the occurrence of supernumerary roots in mandibular molariform teeth of red deer ( Cervus elaphus Linnaeus, 1758) from seven separate populations spanning a range of latitudes in the Iberian Peninsula. We analyzed the influence of several factors, including sex, origin (native vs. reintroduced), lineage, and habitat, to assess extra root prevalence variations. The highest prevalence in deciduous teeth was found in pm 3 (14%) and in permanent teeth in M 1 (3%). We found significant differences between areas, lineages, and soil type; however, no significant relationships were found with the origin or the sex of individuals. We speculate that the high prevalence of supernumerary roots in M 1 might be related to increased wear in grazers. Furthermore, we suggest that this high prevalence in deciduous teeth might be associated with a hard diet, dry climatic conditions, and a harsh weaning period, which indicate that supernumerary roots might have an adaptive value.

Trichinellosis is a notifiable zoonotic disease caused by parasitic nematode larvae belonging to the genus Trichinella. Domestic pig and wild boar are important hosts within the natural cycle of T. spiralis, the last one being an animal whose populations have experienced an important growth. Therefore, this paper studies the prevalence of Trichinella infection in wild boar in Spain, as well as its relation with hunting and its impact on public health during the period 2006–2019. For this purpose, different sources of information were consulted and analyzed depending on the autonomous communities of Spain and years. During the fourteen years of study, the number of wild boars hunted and the number of cases of Trichinella infection in them increased (from 172 cases in 2006 to 421 in 2019), although prevalence values remained low as the number of animals analyzed also increased. On the other hand, trichinellosis in humans tended to decrease (from a peak of 107 cases in 2007 to 11 cases in 2019). Nevertheless, the numbers of both wild boars and humans infected with Trichinella in Spain are among the highest in Europe, and this emphasizes the importance of food safety, sanitary controls of game meat and citizen awareness campaigns, which prevent the spread of Trichinella through the human population.

The aim of this study was to obtain an effective tool for sex determination in Eurasian Eagle Owls (Bubo bubo), a species without marked sexual dimorphism, by taking external body and bone measurements. Thirty-one individuals were used for this purpose, 16 males and 15 females, and 42 measurements were obtained: 19 external and 23 bone measurements. Three discriminant analyses were carried out: the first with external measurements only, a second one with bone measurements only, and a third combining both. The validation of the classification was performed by cross-validation. The first analysis led to a discrimination function with five external measures, with a Wilk’s Lambda of 0.064 and 100% of the individuals classified correctly. The second analysis led to a discrimination function with two bone measures, with a Wilk’s Lambda of 0.282 and 90% of individuals correctly classified. The third analysis led to a discrimination function with six external and two bone measures, with a Wilk’s Lambda of 0.022 and 100% of individuals classified correctly. The study has shown that external measurements are more efficient than bone measurements, and likely sufficient for sexing. Nevertheless, bone measurements can provide complementary information, although alone they are insufficient for sexing owls, given that the length of the ulna and the nose bones were the only useful bone measurements. It can be generalized that this work provides an optimal sexing method, useful in ornithological ecology, clinical and forensic medicine, as well as in archaeozoological studies.