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Recent focus has been given on the effects of high-intensity infrasound (HII) exposure, and whether it induces changes in pancreatic morphology and glucose metabolism is still unknown. As such, we have studied the impact of HII exposure on glucose tolerance, insulin sensitivity, pancreatic islet morphology, muscle GLUT4 and plasma insulin and corticosterone levels. Normal and glucose intolerant wild-type Wistar rats were randomly divided in two groups: one group not exposed to HII and the other continuously exposed to HII. Animals were sacrificed at three timepoints of exposure (1, 6 or 12 weeks). An intraperitoneal glucose tolerance test was performed, blood samples were collected and the pancreas and the quadriceps femoris muscle were excised. Circulating insulin and corticosterone levels were determined and pancreatic and muscular tissue were routinely processed for histochemistry and immunohistochemistry with an anti-GLUT4 antibody. Animals exposed to HII had higher corticosterone levels than animals not exposed. No differences were found on insulin concerning HII exposure or glucose intolerance. Glucose intolerant animals had pancreatic islet fibrosis and no differences were found in GLUT4 ratio concerning HII exposure. In conclusion, we found that continuous exposure to HII increases stress hormone levels without inducing glucose intolerance in rats. [ABSTRACT FROM AUTHOR]

Hard coral coverage contributes to increasing the structural complexity of coral reefs, provides biological resources and drives biological and ecological interactions among reef organisms. Declines in the structural complexity and coral diversity of tropical reefs, due to the influence of anthropogenic activities, have been reported around the world in recent decades; however, coral reefs on the continental coast of Ecuador have been poorly studied. From September 2017 to April 2018, the method of permanent belt transects and quadrats was used to assess the status of coral (percentage of live, dead and fractured coral) to determine the contribution of derelict fishing gear to the process of coral fracture, which causes loss of structural complexity on two marginal coral-rocky reefs in the central coast of Manabi-Ecuador: Perpetuo Socorro and Ureles. Three geomorphological zones [crest (5–7 m depth), slope (7–10 m depth) and bottom (10–13 m depth)] were assessed. Results show that the crest zone in Ureles reef was highly affected by the entanglement of nets compared with Perpetuo Socorro, and identify derelict fishing gear as a key driver in the process of the fracturing and fragmentation of coral. Seasonal and site-associated factors also had a significant effect on the structural complexity of the reef studied. Destruction of coral in the crest zones drastically affects invertebrate and fish communities. We recommend a periodical assessment to measure the loss of structural complexity plus the implementation of a recovery program for the reefs studied that involves the education, active participation and collaboration of artisanal fishermen, governmental organizations and universities. [ABSTRACT FROM AUTHOR]

Monitoring European rabbit (Oryctolagus cuniculus) populations using suitable methods is crucial, especially in those areas in which endangered predators remain and rabbits occur at low densities. We first counted the number of rabbits, the number of scattered pellets, and the number of latrines counted within 16 plots established in areas of low rabbit density, showing that the number of rabbits counted inside the plots was more closely correlated with the number of pellets counted than with the number of latrines. In addition, no latrines were found in 8 plots. In 53 walking transects, the number of pellets m−2 and the number of latrines km−1 had a positive relationship, but no significant correlation was obtained between the two methods when only the transects with a low rabbit abundance were selected. These results suggest that although counting latrines can be useful to compare areas with different abundances, it may underestimate rabbit abundance at low abundances where counting scattered pellets is, therefore, the most accurate alternative. [ABSTRACT FROM AUTHOR]

Rabbits can successfully avoid their enemies by evaluating the risk of predation. They have various defensive strategies, such as morphological adaptations and behaviours patterns, which enable them to perceive their predators and thus reduce the risk of predation. It is well documented that rabbits recognise the scats of terrestrial predators and avoid those areas in which they are present. However, few studies show whether the prey species can recognise the presence of congeners in carnivores’ scats, which would allow them to identify their predators in a more efficient manner. We have carried out a comparative analysis of the use of space made by rabbits on plots on which a neutral odour (water) or the odours of the ferrets’ scats that had consumed either rabbit or another mammal (beef) were applied. Our results showed a lower number of rabbit pellets on those plots containing predator odours than on the control plots. During the first 6 days after applying the first odour, the number of rabbit pellets was lower on plots on which rabbit had been included in the diet when compared with scats obtained from a beef diet. However, no differences between the two experimental plots were recorded during the third visit (9 days after applying the first odour). Our results suggest that rabbits may be able to detect congeners in their predators’ scats, thus leading them to, in the short term, avoid areas in which their terrestrial predators’ diet is based on conspecifics, probably as the result of them perceiving a higher risk of predation. [ABSTRACT FROM AUTHOR]

European rabbit translocation is an extended practice in Spain, France, and Portugal, for both conservation and hunting purposes. Some of these translocations are carried out with the aim of reinforcing existing rabbit populations. In these cases, some of the new rabbits are released into warrens already occupied by resident conspecifics. This could have a negative impact upon both the released and the resident individuals owing to the “dear enemy” effect and the territoriality of the resident rabbits. In this study, we evaluated the effect of rabbit release into occupied warrens, in small areas populated by low-density resident rabbit populations. We observed negative effects at two different levels: the number of active entrances per recipient warren and the number of active warrens per reinforced plot, in addition to a general lack of increase in rabbit abundance in the area and, therefore, the failure of the reinforcement actions. Our results strongly suggest that the release of European rabbits into warrens occupied by resident rabbits is contraindicated if the objective is to recover rabbit populations in the area. [ABSTRACT FROM AUTHOR]

Hunting activities are responsible for the translocation and restocking of millions of animals throughout Europe, including the introduction of alien species. In a context of the growing use of game translocations and of increasing concern about the impact of biological invasions, our goal is to review the role of alien species introduced primarily for hunting purposes on the European scale. In particular, we explore: (1) the relative importance of game species in the context of alien species introductions; (2) the temporal evolution of the number of species introduced for hunting purposes; (3) the contribution of different taxa; (4) the pattern of introduced game species composition across countries (in terms of similarity), and (5) the underlying human demographic factors driving the diversity of introduced game species per country. According to our results, 24.3% of the mammals and 30.2% of the birds introduced into Europe during the last century were released primarily for hunting purposes, in total, 93 species (63 birds and 36 mammals), the most important taxa being Artiodactyls, Anseriformes and Galliformes. The species composition differed among countries, with a higher diversity of introduced game species in larger countries and in those with a higher human population density and proportion of hunters. This review stresses that hunting was a significant pathway for the introduction of invasive species into Europe in the last century. Since some of the game species introduced have had severe environmental impacts on many European regions, and introductions of non-native game species are still occurring, it is essential to improve regulations and increase public awareness regarding invasive game animals. This will help to preserve biodiversity and improve the sustainability of current hunting schemes in increasingly managed European ecosystems. [ABSTRACT FROM AUTHOR]

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The wild boar has, over the past few decades, undergone an expansion in Europe, which may have negatively affected ground-nesting bird populations and particularly those of wading birds. The aim of this study was to evaluate predation on waders' nests by wild boar in Sweden, where this species has been increasing since its reintroduction. This was done by placing artificial nests in seven different study areas. A comparison was then made of predation rates of the nests placed on control plots (areas in which no wild boar were present but other predators were) and plots containing different abundances of wild boar. Contrary to our expectations, the proportion of nests predated was significantly lower in those areas in which wild boar were present, with a predation rate of 54 %, whereas the predation rate was 87.5 % in the others. The wild boar was identified as the second most important nest predator in the plots in which it was present, accounting for 18 % of the predated nests. The main predator on both types of plots was the red fox, which was responsible for 28 and 38.5 % of the predated nests on plots with/without wild boar, respectively. Interestingly, predation by badgers occurred principally in areas in which the wild boar was absent (34.5 % of the predated nests), whereas only one nest was predated by this predator in areas containing wild boar. It is not, however, possible to state whether predation by badgers was lower because of the presence of wild boar or whether this was owing to the fact that badgers do not select those particular patches because of habitat features. [ABSTRACT FROM AUTHOR]

Predation is an important selective force on prey species, but avoiding predators can be costly. Efficient decisions on who to avoid (predator recognition) and when (situations with different predation risk) will determine the chances of prey survival. In coevolved predator-prey systems, detection of predator odours generally induces a response in potential prey to reduce predation risk. However, prey may not necessarily respond to odours of predators with which they have no previous experience, as predicted by the prey naïveté hypothesis. In turn, perceived predation risk may also modulate predator recognition and the intensity of antipredator responses. In this study, we investigate the responses of an introduced prey species, the European rabbit ( Oryctolagus cuniculus), to odours from coevolved and non-coevolved, sympatric and allopatric predators in situations of high and low numbers of predators in Australia. We used pellet counts to quantify rabbits' use of space on experimental plots treated with predator odours. Rabbit avoidance of plots scented with coevolved predator odours was strongest, but they also responded to non-coevolved, marsupial predators. Predator abundance did not affect predator recognition in rabbits, although responses were more intense in situations where perceived predation risk was low and the intensity of responses decreased over time. Our results suggest that rabbits may have learned to recognize novel marsupial predators after 150 years of exposure in their introduced range. [ABSTRACT FROM AUTHOR]

Increases in the deposition of nitrogen affect biodiversity and the composition of natural vegetation. A significant amount of this nitrogen may originate not only from intensive agricultural and livestock farming, but also from wild ungulates whose abundance and area of distribution are currently increasing in the Iberian Peninsula. In this study we have estimated the abundance of two species of wild ungulates (red deer and wild boar) and the amount of nitrogen contained in their droppings and in the grass. We have also recorded the herbaceous community. The results show that the density of these ungulates is positively correlated to an increase in the grass nitrogen, which adversely affects the percentage of leguminosae in pastures. These results suggest that high densities of ungulates may be affecting plant communities by increasing the amount of nitrogen as a result the deposition of droppings. The current system of big game management should therefore be reviewed to make it compatible with the conservation of plant communities and small herbivore species that may be negatively affected by changes in pasture quality and quantity. [ABSTRACT FROM AUTHOR]

Understanding how non-invasive indicators of diet quality, such as faecal nitrogen (FN), relate to population performance is a valuable asset when assessing the management of wild ungulates. However, the relationships between FN and protein intake may depend on the ingestion of less palatable plants containing high quantities of tannin (which is known to reduce degradable proteins) and management schemes (such as supplemental feeding). In order to describe the factors and potential use of FN as an indicator of diet quality, we selected a range of red deer ( Cervus elaphus) densities in Mediterranean habitats in South Central Spain, which were classified under different management regimens (with and without food supply). We specifically aimed to (i) identify the main population (management, density) and diet quality factors related to FN levels, (ii) assess the relationship between individual performance (body condition measured as kidney fat index, KFI) and FN and (iii) provide evidence of the modulating role that management may play in this relationship. FN was positively associated with the faecal tannin concentration and the density of deer. Interestingly, a positive correlation was observed between FN and nitrogen in plants on hunting estates with a supplemental food supply, whereas this relationship was not evident in the absence of supplemental feeding. Moreover, KFI was negatively associated with FN, and this negative association was more marked in the presence of supplemental feeding. This study exemplifies that caution is necessary when the interpretation of individual FN values is used to monitor the performance of red deer populations, particularly in high density contexts with a reduced quality of forage, and when supplemental food is provided. However, when FN is interpreted in concomitance with body condition, population parameters and diet quality, it has been proved to be a potentially simple, cost-effective and reliable indicator of biological performance and diet quality. [ABSTRACT FROM AUTHOR]

Secondary tumours of the thyroid gland account for 1.25 to 3 % in clinical series and reach 24 % in autopsy series. Chondrosarcoma is a rare malignant mesenchymal tumour of chondrogenic nature; the mesenchymal variant represents less than 3 % of all chondrosarcomas, being therefore extremely rare. A mesenchymal chondrosarcoma metastasis in the thyroid is exceptional; to our knowledge, only three previous cases of chondrosarcoma metastasis in the thyroid have been reported to date but none of such cases corresponded to a mesenchymal chondrosarcoma. We present the first of such a case in a 27-year-old woman with a 4-year history of mesenchymal chondrosarcoma of the sacrum that was treated by surgery and chemotherapy. At the present admission, head and neck computed tomography revealed a well-defined nodule in the thyroid gland. The diagnosis of metastasis from the mesenchymal chondrosarcoma was made in the right lobectomy specimen. [ABSTRACT FROM AUTHOR]

Over the past few decades, the wild boar has been undergoing an expansion in Europe, which may have negatively affected small game populations and particularly red-legged partridges. We aim to evaluate the red-legged partridge nest predation by wild boar at high boar abundances by placing artificial nests in nine big game estates. Predation rates were compared between nests placed in fenced controlled plots with no wild boar access (but accessible to other predators) and open plots in which the wild boar gains access. The proportion of nests and eggs predated was significantly lower in wild boar exclusion areas, recording a predation rate of 50 % for the nests and 38 % for the eggs in these areas, whereas in the presence of wild boar, the predation rate was 80 % for the nests and 58 % for the eggs. Moreover, the wild boar was identified as the main nest predator in unfenced areas, accounting for 36 and 48 % of the predated nests and eggs respectively. This study sheds light on the wild boar predation on nests of the red-legged partridges. [ABSTRACT FROM AUTHOR]

About half a million rabbits are translocated in southwestern Europe every year for conservation and hunting purposes. However, the success of traditional rabbit restocking is generally extremely low, and this has been attributed to short-term predation by mammalian carnivores. Hence, recent recovery programs have tackled the problem of terrestrial predators with the use of exclusion fences, but no additional measures have been employed to avoid aerial predation. In this study, we have therefore conducted a field experiment to test the short-term effect of total predation exclusion in rabbit restocking enclosures, comparing rabbit abundance in plots which are only accessible to raptors (top-open plots) and plots which are accessible to neither carnivores nor raptors (top-closed plots). The results showed that the top-closed plots had higher rabbit abundance in the short term, and the highest difference in rabbit abundance between the two kinds of fences was attained in the first 2 weeks. We therefore conclude that the top-closed plots were an effective tool to increase rabbit abundance during the first weeks after release through the exclusion of raptor predation. [ABSTRACT FROM AUTHOR]

Olfactory signalling is widespread among mammal inter- and intra-specific communication systems. Social mammals use latrines (faecal accumulations) as a communication system, which address the needs of individuals both inside and outside the social group. Latrines are commonly used as olfactory and visual signals for the delimitation of territories, and the location of these signals may thus provide useful clues for the study of the marking animals' behaviour and the delimitation of a spatial framework for these studies. In this work, we have tested the application of indigestible faecal markers in order to define territorial boundaries marked by latrines in wild rabbit social groups. Different combinations of baits and markers were first tested on wild rabbits kept in captive conditions, and the best combinations were then applied to rabbits in semi-natural conditions in order to test their feasibility for use with wild populations. As one possible application of the method, Minimum Convex Polygons and Kernel density estimators were used to analyse the distribution of the latrines of three wild rabbit social groups in semi-natural conditions. The results of this showed that the marked bait method is a useful tool for exploring the territorial behaviour of social mammals that use latrines for communication. It can also provide useful information for the definition of spatial frameworks based on social structures, and is fast, straightforward, easy, cheap, and does not require specialised training. [ABSTRACT FROM AUTHOR]

Various methods have been used to estimate rabbit abundance, but comparisons of standard methods are still lacking, and thus, results remain roughly comparable across studies. Ideally, a method should be applicable over a wide range of situations, such as differing abundances or habitat types. Comparisons of methods are required to evaluate the benefits of each of them, and survey methods should be validated for the conditions in which they will be used. In this study, we compare the performance of direct methods (kilometric abundance index and distance sampling) in two seasons and at two times of day (dusk and night) for estimating wild rabbit abundances in agricultural landscapes. Estimates based on direct methods were highly correlated and detected similar seasonal population changes. Night counts provided better estimates than did dusk counts and exhibited more precision. Results are discussed within the context of rabbit behaviour and their implications for rabbit population surveys. [ABSTRACT FROM AUTHOR]

The study of blood chemistry provides important information about many aspects of the biology and physiology of animals. It is known that many factors can influence the results of such analyses. A proper knowledge of these effects is necessary to correctly interpret the results. In this paper, we analyzed the daily variations of blood biochemical parameters of 32 captive red-legged partridges ( Alectoris rufa) of both sexes to test the effect of the daily cycle on these parameters. We found daily variation in glucose, cholesterol, uric acid, triglycerides, and calcium, but not in total protein and creatinine. A sex effect was only significant in uric acid. The most reliable data were those obtained from blood samples collected in midday hours. Hence, this time is suggested for blood-sampling in future studies. [ABSTRACT FROM AUTHOR]

The Cabo Cope Unit, which outcrops east of Aguilas (Murcia), belongs to the Maláguide tectonic Complex (Betic Internal Zone) and displays stratigraphic characteristics of particular interest, including Triassic bioclastic carbonate beds which are not common in the Maláguide units. Biostratigrafic fossils have been found in these beds and may correlate with Triassic alpine biofacies. Alpine fauna fossils only appeared in those palaeogeographic units of the Internal Zone of the Cordillera referred to as Alpujárride units, while the influence of the Sephardic faunal province is evident in almost all the cordillera. For these reasons it is noteworthy that new alpine fauna fossils have been found in an Internal Zone unit in which relevant fossils rarely appear. The Triassic succession of the unit studied in this paper can be subdivided into two members: a lower one, which is clastic and contains thick gypsum beds, and an upper one, consisting of carbonate rocks. The lower member has been interpreted as a fluvial-coastal deposit. The upper member is interpreted as a sequence of carbonate ramp deposits. This ramp evolved into a shallow platform with tidal flats typical of a coastal zone. The bivalve fossils Daonella cf. lommeli (Wissmann) and “ Posidonia” sp. have been found in the carbonate member, along with the conodont Sephardiella mungoensis (Diebel). These fossils are of the Late Ladinian age and have been found only in this outcroup of the Betic Cordillera. The presence of this fossil assemblage, which belongs to the alpine faunal province, indicates a connection during the Late Ladinian between the Tethys sea and this area of the Maláguide palaeogeographic domain. The palaeogeographic location of the Cabo Cope Unit during the Middle Triassic was at the south-easternmost part of the Betic Basin, implying that the connection between the Tethys and the Betic Basin was established in the easternmost domains of the basin. [ABSTRACT FROM AUTHOR]

The nesting environment is known to significantly affect the breeding success of sea turtles. Sandy beach habitats, where sea turtles nest, are frequently affected by high tides and waves on Ecuadorian beaches during windy events. The objectives of this study were: i) to determine the variables that affect nest site selection by two sea turtle species, Eretmochelys imbricata and Chelonia mydas in Ecuador, ii) to compare features of the nesting places of successful vs. failed clutches and iii) to quantify the changes in the intensity and frequency of the tide and its relation to the loss of eggs for the last 10 years. We monitored 15 hawksbill and 26 green turtle nests for two years on five beaches on the mainland coast of Ecuador. The results show that the presence of a dune scarps negatively affected successful nesting, while the proportion of eggs lost was positively associated with road distance, sea distance and nest depth. In addition, the results showed that the loss of eggs was greater for the green turtle, the presence of dune scarps and tides. Finally, using the data available on hatching success over the last 10 years we found a significant relationship between the intensity of the tides and the loss of eggs during this period. We conclude that nest site selection and hatching success vary with beach microhabitats and therefore local information is needed to protect suitable habitats. [ABSTRACT FROM AUTHOR]