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1.
Proc Biol Sci ; 291(2015): 20231587, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38228177

RESUMO

Flexibility in activity timing may enable organisms to quickly adapt to environmental changes. Under global warming, diurnally adapted endotherms may achieve a better energy balance by shifting their activity towards cooler nocturnal hours. However, this shift may expose animals to new or increased environmental challenges (e.g. increased predation risk, reduced foraging efficiency). We analysed a large dataset of activity data from 47 ibex (Capra ibex) in two protected areas, characterized by varying levels of predation risk (presence versus absence of the wolf-Canis lupus). We found that ibex increased nocturnal activity following warmer days and during brighter nights. Despite the considerable sexual dimorphism typical of this species and the consequent different predation-risk perception, males and females demonstrated consistent responses to heat in both predator-present and predator-absent areas. This supports the hypothesis that shifting activity towards nighttime may be a common strategy adopted by diurnal endotherms in response to global warming. As nowadays different pressures are pushing mammals towards nocturnality, our findings emphasize the urgent need to integrate knowledge of temporal behavioural modifications into management and conservation planning.


Assuntos
Comportamento Predatório , Refúgio de Vida Selvagem , Animais , Masculino , Feminino , Mamíferos/fisiologia , Cabras/fisiologia , Resposta ao Choque Térmico
2.
Curr Zool ; 68(4): 371-380, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36090138

RESUMO

On a population level, individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes. However, a rigid reliance on photoperiodism can constraint such plastic responses in populations inhabiting temperate latitudes. The regulation of breeding season length may represent a further tool for populations facing changing environments. Nonetheless, this skill was reported only for equatorial, nonphotoperiodic populations. Our goal was to evaluate whether species living in temperate regions and relying on photoperiodism to trigger their reproduction may also be able to regulate breeding season length. During 10 years, we collected 2,500 female reproductive traits of a mammal model species (wild boar Sus scrofa) and applied a novel analytical approach to reproductive patterns in order to observe population-level variations of reproductive timing and synchrony under different weather and resources availability conditions. Under favorable conditions, breeding seasons were anticipated and population synchrony increased (i.e., shorter breeding seasons). Conversely, poor conditions induced delayed and less synchronous (i.e., longer) breeding seasons. The potential to regulate breeding season length depending on environmental conditions may entail a high resilience of the population reproductive patterns against environmental changes, as highlighted by the fact that almost all mature females were reproductive every year.

3.
Sci Rep ; 12(1): 5426, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361851

RESUMO

Settlements are usually shared at different times by semi-fossorial mammals. Porcupine reproductive pair shows high den-site fidelity, but no data are available on the spatio-temporal inhabitation of settlements. In this investigation, the spatio-temporal inhabitation of settlements by crested porcupine families was investigated using camera-trapping as well as the ethological factors affecting the settlements selection. The crested porcupine resulted to be the main inhabitant of settlements surveyed in the present study. Each settlement was inhabited exclusively by one porcupine family. Five out of six porcupine families, each alternatively and complementarily inhabited the same two settlements. In all the five monitored families, settlements selection doesn't follow a seasonal pattern. Settlement inhabitation of porcupines resulted positively affected by cohabitation with badger, while presence of porcupettes did not affect settlements selection. Long periods of settlement inhabitation were positively affected both by the presence of porcupettes and cohabitation with badger. The pattern of settlements inhabitation in relation to their availability and porcupine population density as well as factors promoting porcupine-badger cohabitation should be further investigated. New ethological knowledge obtained in this investigation could be involved in the evaluation of the ecological epidemiology of infectious diseases between porcupine and badger within a one health approach and may be a useful tool for a sustainable management of semi-fossorial mammals.


Assuntos
Mustelidae , Porcos-Espinhos , Animais , Humanos
4.
Sci Rep ; 11(1): 12300, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112859

RESUMO

The aoudad (Ammotragus lervia Pallas 1777) is an ungulate species, native to the mountain ranges of North Africa. In the second half of the twentieth century, it was successfully introduced in some European countries, mainly for hunting purposes, i.e. in Croatia, the Czech Republic, Italy, and Spain. We used neutral genetic markers, the mitochondrial DNA control region sequence and microsatellite loci, to characterize and compare genetic diversity and spatial pattern of genetic structure on different timeframes among all European aoudad populations. Four distinct control region haplotypes found in European aoudad populations indicate that the aoudad has been introduced in Europe from multiple genetic sources, with the population in the Sierra Espuña as the only population in which more than one haplotype was detected. The number of detected microsatellite alleles within all populations (< 3.61) and mean proportion of shared alleles within all analysed populations (< 0.55) indicates relatively low genetic variability, as expected for new populations funded by a small number of individuals. In STRUCTURE results with K = 2-4, Croatian and Czech populations cluster in the same genetic cluster, indicating joined origin. Among three populations from Spain, Almeria population shows as genetically distinct from others in results, while other Spanish populations diverge at K = 4. Maintenance of genetic diversity should be included in the management of populations to sustain their viability, specially for small Czech population with high proportion of shared alleles (0.85) and Croatian population that had the smallest estimated effective population size (Ne = 5.4).


Assuntos
Variação Genética/genética , Genética Populacional , Mamíferos/genética , Ruminantes/genética , Alelos , Animais , República Tcheca , DNA Mitocondrial/genética , Europa (Continente) , Haplótipos/genética , Repetições de Microssatélites/genética , Ruminantes/classificação , Espanha
5.
Neurotoxicology ; 78: 36-46, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32050087

RESUMO

The increased diffusion of the so-called novel psychoactive substances (NPS) and their continuous change in structure andconceivably activity has led to the need of a rapid screening method to detect their biological effects as early as possible after their appearance in the market. This problem is very felt in forensic pathology and toxicology, so the preclinical study is fundamental in the approach to clinical and autopsy cases of difficult interpretation intoxication. Zebrafish is a high-throughput suitable model to rapidly hypothesize potential aversive or beneficial effects of novel molecules. In the present study, we measured and compared the behavioral responses to two novel neuroactive drugs, namely APINAC, a new cannabimimetic drug, and methiopropamine (MPA), a methamphetamine-like compound, on zebrafish larvae (ZL) and adult mice. By using an innovative statistical approach (general additive models), it was found that the spontaneous locomotor activity was impaired by the two drugs in both species: the disruption extent varied in a dose-dependent and time-dependent manner. Sensorimotor function was also altered: i) the visual object response was reduced in mice treated with APINAC, whereas it was not after exposure to MPA; ii) the visual placing responses were reduced after treatment with both NPS in mice. Furthermore, the visual motor response detected in ZL showed a reduction after treatment with APINAC during light-dark and dark-light transition. The same pattern was found in the MPA exposed groups only at the dark-light transition, while at the transition from light to dark, the individuals showed an increased response. In conclusion, the present study highlighted the impairment of spontaneous motor and sensorimotor behavior induced by MPA and APINAC administration in both species, thus confirming the usefulness of ZL as a model for a rapid behavioural-based drug screening.


Assuntos
Comportamento Animal/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Toxicologia Forense/métodos , Psicotrópicos/toxicidade , Peixe-Zebra , Adamantano/análogos & derivados , Adamantano/toxicidade , Animais , Indazóis/toxicidade , Masculino , Metanfetamina/análogos & derivados , Metanfetamina/toxicidade , Camundongos Endogâmicos ICR , Tiofenos/toxicidade
6.
PLoS One ; 14(11): e0224788, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31693689

RESUMO

Forest development is a complex phenomenon which, for the number of actors involved and the response time expressed by forests, is difficult to understand and explore. Forests in Italy, as in several areas of Europe, are experiencing intensive management and recently, an increasing impact by ungulates. The effects on forest development of these two disturbances combined are difficult to predict, and consequently to be properly managed. We used a forest landscape change model, LANDIS-II, to simulate forest development as driven by forestry practices and roe deer impact for 200 years in a mountain forest of the Italian Apennines. We found that each disturbance alters forest tree species richness, forest type abundance and distribution, and forest structure. When considered combined, the two disturbances show additive behavior, enhancing or moderating each other's effects. Forest management has a negative effect on tree species richness. We expected roe deer to have a negative effect on harvest yields, but this result was significant only for two of seven harvesting treatments. On the other hand, roe deer presence had a positive effect on tree species richness. All the simulation scenarios returned some extent of forest loss. The amount of the forest loss is lowest in the scenario without disturbances, and greatest when both disturbances are considered. However, the two disturbances combined, with the magnitude modelled in our simulations, have relatively low effects on the forest dynamics we analyzed in our study area. LANDIS-II was an effective approach for simulating combined management and ungulate driven trends of forest development, and to help understand the dynamics that lay behind it.


Assuntos
Cervos/fisiologia , Monitorização de Parâmetros Ecológicos/métodos , Agricultura Florestal/métodos , Florestas , Árvores/fisiologia , Distribuição Animal , Animais , Mudança Climática , Simulação por Computador , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Política Ambiental , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/estatística & dados numéricos , Itália , Modelos Estatísticos , Dispersão Vegetal
7.
PLoS One ; 14(10): e0222349, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31600228

RESUMO

Roe deer (Capreolus capreolus) is the most abundant cervid in Europe and, as such, has a considerable impact over several human activities. Accurate roe deer population size estimates are useful to ensure their proper management. We tested 3 methods for estimating roe deer abundance (drive counts, pellet-group counts, and camera trapping) during two consecutive years (2012 and 2013) in the Apennines (Italy) in order to assess their precision and applicability. During the study period, population density estimates were: drive counts 21.89±12.74 roe deer/km2 and pellet-group counts 18.74±2.31 roe deer/km2 in 2012; drive counts 19.32±11.12 roe deer/km2 and camera trapping 29.05±7.48 roe deer/km2 in 2013. Precision of the density estimates differed widely among the 3 methods, with coefficients of variation ranging from 12% (pellet-group counts) to 58% (drive counts). Drive counts represented the most demanding method on account of the higher number of operators involved. Pellet-group counts yielded the most precise results and required a smaller number of operators, though the sampling effort was considerable. When compared to the other two methods, camera trapping resulted in an intermediate level of precision and required the lowest sampling effort. We also discussed field protocols of each method, considering that volunteers, rather than technicians, will more likely be appointed for these tasks in the near future. For this reason, we strongly suggest that for each method managers of population density monitoring projects take into account ease of use as well as the quality of the results obtained and the resources required.


Assuntos
Comportamento Animal/fisiologia , Cervos/fisiologia , Densidade Demográfica , Animais , Europa (Continente) , Feminino , Humanos , Itália
8.
Sci Rep ; 9(1): 3048, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816191

RESUMO

Avoiding hyperthermia entails considerable metabolic costs for endotherms. Such costs increase in warm conditions, when endotherms may trade food intake for cooler areas to avoid heat stress and maximize their energy balance. The need to reduce heat stress may involve the adoption of tactics affecting space use and foraging behaviour, which are important to understand and predict the effects of climate change and inform conservation. We used resource selection models to examine the behavioural response to heat stress in the Alpine ibex (Capra ibex), a cold-adapted endotherm particularly prone to overheating. Ibex avoided heat stress by selecting the space based on the maximum daily temperature rather than moving hourly to 'surf the heat wave', which minimised movement costs but prevented optimal foraging. By integrating these findings with new climate forecasts, we predict that rising temperatures will force mountain ungulates to move upward and overcrowd thermal refugia with reduced carrying capacity. Our approach helps in identifying priority areas for the conservation of mountain species.


Assuntos
Migração Animal/fisiologia , Animais Selvagens/fisiologia , Aquecimento Global , Resposta ao Choque Térmico/fisiologia , Ruminantes/fisiologia , Aclimatação/fisiologia , Animais , Conservação dos Recursos Naturais , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Metabolismo Energético/fisiologia , Previsões , Temperatura Alta , Locomoção/fisiologia , Masculino , Estações do Ano , Análise Espaço-Temporal
9.
PLoS One ; 10(6): e0130957, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26111118

RESUMO

The importance of capturing wild animals for research and conservation projects is widely shared. As this activity continues to become more common, the need to assess its negative effects increases so as to ensure ethical standards and the validity of research results. Increasing evidence has revealed that indirect (physiological and behavioural) effects of capture are as important as direct risks (death or injury) and that different capture methodologies can cause heterogeneous effects. We investigated the influence of chemical immobilisation on Alpine ibex (Capra ibex): during the days following the capture we collected data on spatial behaviour, activity levels of both males and females, and male hormone levels. Moreover, we recorded the reproductive status of each marked female during the breeding seasons of 15 years. Then, by several a priori models we investigated the effects of the capture taking into account biological factors and changes in environmental conditions. Our results showed that chemical immobilisation did not affect either spatial behaviour (for both males and females) or male hormone levels, though both sexes showed reduced activity levels up to two days after the capture. The capture did not significantly affect the likelihood for a female to give birth in the following summer. Our findings highlighted the scarce impact of chemical immobilisation on ibex biology, as we detected alteration of activity levels only immediately after the capture if compared to the following days (i.e., baseline situation). Hence, the comparison of our findings with previous research showed that our methodology is one of the less invasive procedures to capture large mammals. Nonetheless, in areas characterised by high predator density, we suggest that animals released be carefully monitored for some hours after the capture. Moreover, researchers should avoid considering data collected during the first days after the manipulation in order to avoid biased information.


Assuntos
Comportamento Animal/efeitos dos fármacos , Imobilização/métodos , Ketamina/administração & dosagem , Relaxantes Musculares Centrais/administração & dosagem , Xilazina/administração & dosagem , Animais , Animais Selvagens , Feminino , Cabras , Imobilização/efeitos adversos , Masculino , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Comportamento Espacial/efeitos dos fármacos , Comportamento Espacial/fisiologia , Testosterona/sangue
10.
Oecologia ; 178(1): 187-95, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25556530

RESUMO

Although numerous studies have reported reproductive senescence in wild animal populations, we still know very little on inter-individual differences in rates of ageing and on the factors accounting for these differences. To investigate age-related variation in breeding success in a natural population of Alpine chamois (Rupicapra rupicapra), we used 15 years of data obtained by monitoring individual ear-tagged females. Analyses at the population level confirmed the occurrence of a decline in female breeding success, which is most noticeable from 9 years of age onward. Using an age-reverse approach, we showed that senescence in female breeding success occurs at the same age, since only very old individuals (older than 16 years) showed a decline in breeding success in the years preceding death. Interestingly, we also found evidence that 'success comes from success', as females that gave birth in a given year were more likely to procreate again in the following year. Moreover, results showed that discrepancies between successful and unsuccessful individuals tend to become more relevant in the oldest age classes. There was no evidence of a terminal allocation. These results emphasize the importance of age-dependent effects and individual quality in shaping reproductive senescence in a wild long-lived ungulate.


Assuntos
Envelhecimento/fisiologia , Cruzamento , Reprodução , Rupicapra/fisiologia , Fatores Etários , Animais , Animais Selvagens , Feminino , Gravidez
11.
Chronobiol Int ; 30(6): 772-85, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23738905

RESUMO

We investigated the activity patterns of a European roe deer (Capreolus capreolus) population living in a forested Apennine area in central Italy, in order to shed light on the environmental and biological factors that were expected to account for the observed activity patterns on daily and yearly bases. Daily and seasonal activity patterns of 31 radio-collared roe deer were assessed through sessions of radio tracking for a total period of 18 consecutive months. Roe deer showed bimodal activity patterns throughout the year, with the two highest peaks of activity recorded at dawn and dusk. Activity patterns of males and females differed during the territorial period (from early spring to late summer), whereas they did not during the nonterritorial period. Most likely, behavioral thermoregulation can be held responsible for variation of daily activity patterns in different seasons. In winter, for instance, activity during the dawn period was significantly higher than in other seasons and daylight activity was significantly higher than at night. Nocturnal activity was highest in summer and lowest in winter. During the hunting season, moreover, roe deer showed lower activity levels than during the rest of the year. The prediction that roe deer would show lower activity levels during full moon nights, when the predation risk was assumed to be higher, was not confirmed by our data. Activity rhythms in roe deer were thus subjected to both endogenous and environmental factors, the latter working as exogenous synchronization cues. Accordingly, in changing environmental and ecological conditions, a circadian cycle of activity could be seen as the result of complex interactions among daily behavioral rhythm, digestive physiology, and external modifying factors.


Assuntos
Comportamento Animal , Relógios Biológicos , Cervos/fisiologia , Estações do Ano , Animais , Tamanho Corporal , Temperatura Corporal , Ritmo Circadiano , Ecologia , Meio Ambiente , Feminino , Itália , Masculino , Tecnologia de Sensoriamento Remoto , Semicondutores , Fatores Sexuais , Árvores
12.
Behav Processes ; 98: 44-50, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23669063

RESUMO

Alternative mating tactics (AMTs) are intrasexual variants in mating behaviour of several species ranging from arthropods to mammals. Male AMTs coexist between and within populations. In particular, male ungulates rarely adopt just one tactic throughout their lifetime. Tactics commonly change according to internal factors (age, body size, condition) and external conditions (weather, resources, predation, animal density). However, the influence of weather has not yet been investigated in upper vertebrates. Such influence may be relevant in species whose rutting period occurs late in fall or in winter, when environmental conditions and the snow cover in particular may vary considerably. We detected two AMTs in Alpine ibex (Capra ibex) males: older and full-grown males mainly adopted the tending tactic, while younger males usually pursued an alternative one (coursing tactic). Weather was found to influence the use of AMTs by males: in snowy mating seasons, the coursing tactic was no longer used due to difficulties in moving through deep snow. In snowy rutting periods, males appeared to delay or even avoid mating activities and a decrease of births was reported in the second part of the following birth season. Snow cover may have a negative effect on population dynamics by reducing the recruitment and on population genetic variability, as a consequence of poorer mating opportunities. Studies on factors affecting mating behaviour and leading to a reduced availability of mates and a decrease in female productivity are especially relevant in species, like Alpine ibex, whose genetic variability is low.


Assuntos
Altitude , Cabras/fisiologia , Reprodução/fisiologia , Estações do Ano , Comportamento Sexual Animal/fisiologia , Neve , Animais , Feminino , Masculino , Dinâmica Populacional
13.
Behav Processes ; 77(3): 408-12, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18029113

RESUMO

Observations of the flight response in mammals are commonly used to test the behavioural response to predation risk. Such a response is likely to be stronger in more sensitive individuals such as females, and females with offspring in particular, as well as during such periods as the birth season. From August 2005 to July 2006 we recorded the flight distances of different mouflon group types in a natural population in Sardinia. The comparison of the flight distances of the groups (n groups=375, n mouflons=1303) provided evidence for the key role of lamb presence. Female groups with lambs fled at greater distances than male groups and female groups without lambs. This difference was linked to the females' priority to secure the survival of their offspring. Indeed, the uniformity of the flight distances of males and non-reproductive females was in contrast to the general expectations regarding ungulate species. In fact, smaller females were expected to be more sensitive to predation risk than larger males. The absence of major differences is probably due to the low sexual dimorphism of mouflon. Flight distances were shorter during the rut than during the lambing season, arguably because during the mating less time and energies were available for anti-predator behaviour. However, during the rut females with lambs still fled at greater distances than females without lambs, arguably because mothers took it as a priority to protect their parental investment rather then to find a potential mate.


Assuntos
Reação de Fuga/fisiologia , Comportamento Materno/fisiologia , Ovinos/fisiologia , Animais , Feminino , Masculino , Comportamento de Massa , Fatores Sexuais
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