Effect of anthropic disturbances on the activity pattern of two generalist mesocarnivores inhabiting Mediterranean forestry plantations

Humans have been altering the Mediterranean landscapes for millennia. To diminish the probability of encounters with domestic animals, humans and their activities, many species adjust their behavior to become more nocturnal. Even habitat-generalist species, such as red fox and stone marten that are somehow tolerant to environmental changes, might be affected by anthropic disturbances. Nevertheless, only a small number of studies were implemented in Iberia targeting these mesocarnivores’ activity patterns, and fewer have assessed the temporal ecology of these species in Eucalyptus plantations, the current main forest cover in Portugal. Based on camera traps, we aimed to analyze: 1) the temporal and spatio-temporal activity patterns of red fox and stone marten; and 2) how they are affected by distinct human disturbances (i.e., humans, livestock, dogs, plantations, and hunting). Foxes presented a higher crepuscular activity, while martens were entirely nocturnal, suggesting some avoidance behavior. Both mesocarnivores showed a higher overlap with dogs’ activity than with humans or livestock. Foxes’ activity patterns vary between seasons and habitats but were not influenced by the hunting period. Results suggest that both mesocarnivores, besides setting apart their activity from humans related disturbances, also show a tendency to temporally avoid each other. While the increase of nocturnality may indicate an anthropic disturbance impact, a reduction of activity overlap between mesocarnivores may be a strategy to reduce competition. These results may help support the sustainable management of landscapes by highlighting critical periods where activity overlaps may occur, and thus the anthropic impacts on wildlife are higher.info:eu-repo/semantics/publishedVersio

Spatio-temporal ecology of cervids in Eucalyptus plantations

Tese de mestrado, Biologia da Conservação, Universidade de Lisboa, Faculdade de Ciências, 2021Human population growth has led to an increase in demand for forest and agroforestry products (e.g., wood). Deforestation caused by the exploitation of these resources is partially compensated by planting of new production forests, as is the case with eucalyptus plantations. These anthropogenic environments often affect the occurrence of animal and plant species due to their biological, structural and management characteristics. In Portugal, eucalyptus plantations are widespread, occupying a quarter of the total forested area. The roe deer (Capreolus capreolus) and red deer (Cervus elaphus) are Cervidae species whose population has been growing in recent years in the country and as sympatric species they are ideal study models to understand how eucalyptus plantations change the spatial and temporal behavior of animals. In this study, using camera trapping methods, we analyzed the interaction between roe deer and red deer in eucalyptus plantations and areas of native vegetation and the occupancy and activity patterns exhibited by these species. We used conditional occupancy models of two species to obtain species interaction factors and to assess the spatial patterns we used single season, single species occupancy models. We calculated the temporal patterns using non-parametric kernel density estimator. The presence of eucalyptus plantations had a negative influence on the occupancy probability of both species. The species also have different interactions patterns in distinct eucalyptus plantations production stages, which indicates that the structure of the eucalyptus changes how the species use it. Anthropogenic disturbance has a major impact on the spatial and temporal ecology of these cervids. Human activity and infrastructures promote these species avoidance behavior, abandoning highly disturbed areas or altering their activity pattern, as with red deer that became more active during sunrise time to lower the chance of human encounter in Eucalyptus plantations. This study may serve as a reference for the spatial, temporal, and interspecies behavior of roe deer and red deer in the southwestern limit of their geographic range and how these species are affected by the presence of eucalyptus plantations. Therefore, we suggest measures to reduce the impact of Eucalyptus plantations on local deer population. Maintaning stands age heterogeneity and reducing work activities during the crepuscular hours to ensure normal deer behavior. Allowing small patches of native vegetation within plantation stands to provide food and refuge to roe and red deer. The knowledge generated by this study will be crucial for the sustainable management of these plantations and the populations of ungulates that inhabit them

Determinants of the relative abundance of rodents in landscapes dominated by Eucalyptus plantations

Forestry plantations have increased considerably over recent decades to fulfil human demand for wood, pulp and paper. Eucalyptus globulus Labill is one of the most abundant plantation species, particularly in Europe, where its largest presence is in Portugal. Furthermore, plantations in Mediterranean areas, such as Portugal, frequently suffer from forest fires, and thus it is crucial to understand their impacts on vertebrates. This is especially relevant for some species, like small mammals, that use landscapes at smaller scales for which even small changes in forest cover may have a profound effect. In this study, we evaluate the effects of several environmental, disturbance and habitat drivers on the relative abundance of rodents (Muridae) in Eucalyptus plantations in central Portugal. Specimen capture took place across two seasons and at eight study sites representing six different stages of Eucalyptus plantations and two native forests from 2019 to 2020. Using a structural equation modelling approach, we show that the relative abundance of rodents was promoted by recent wildfire events and was higher in areas where carnivores and wild boar were more abundant. By contrast, abundant deer and increased percentages of herbaceous or litter cover and bare soil limited the abundance of rodents. We did not detect a significant relationship between Eucalyptus plantations and the relative abundance of rodents. The presence of other species, either by direct contact (carnivores) or by inducing habitat changes (ungulates), and vegetation structure, likely linked to plantation management or fire regime, are the more important factors dictating the population dynamics of rodents across plantation forests in central Portugal.info:eu-repo/semantics/acceptedVersio

Eucalyptus plantations alter spatiotemporal relationships of wild ungulates

Eucalyptus plantations, the second most economically important exotic tree in Europe, cover circa 1,5 million hectares on this continent. However, little is known about their effect on the ecological patterns of widely distributed and increasing populations of wild ungulates. This lack of knowledge jeopardizes our ability to correctly manage these populations in increasingly ubiquitous exotic forests. We aimed to understand how exotic forestry plantations influence ungulates spatial and temporal dimensions of their niche and determine how the species interactions may be changed by these artificial systems. We used roe deer and red deer as wildlife models, the Portuguese Eucalyptus plantation as standards for forestry plantations, and camera-trapping, occupancy modeling, and kernel density estimators as tools to fulfill our goals. Eucalyptus plantations had a strong effect on roe deer and red deer spatial behavior when compared to areas dominated by native vegetation. Both species seem to avoid disturbed areas such as agricultural land and Eucalyptus plantations. Even when using plantations, they shift their activity to reduce human encounters. Furthermore, plantations are not a homogeneous landcover, and thus distinct production phases of Eucalyptus plantations affect species interactions and activity patterns differently. Our results show that the pre-harvesting phases seem to be the more critical period for deer. Thus, production forest managers must guarantee that plantation structure encompasses areas with different tree ages to minimize this effect and fulfill deer’s food and cover requirements. Forestry activities should avoid dawn and dusk, to minimize disturbance and to reduce the negative interaction between sympatric guild members, by allowing species to be sparsely distributed (and not clustered in the few undisturbed patches). Plantations should include dispersed native patches to which animals may move in search of food and refuge, therefore creating discontinuities within plantations.info:eu-repo/semantics/acceptedVersio

Drivers of occupancy patterns for the red fox, Vulpes vulpes, in Mediterranean Eucalyptus plantations

The replacement of natural areas with forestry plantations is a worldwide expanding process with direct consequences for biodiversity and ecosystem functionality. In the Mediterranean region, Eucalyptus spp. plantations are widespread, forming monospecific landscapes that in Portugal dominate most of its forested areas. The reduction in the availability of native habitats induces important challenges to native wildlife, namely changes in habitat use patterns and behavior. In this study, we evaluated the influence of Eucalyptus globulus exotic plantations on the occupancy patterns of the red fox (Vulpes vulpes L.), a mesocarnivore widely distributed in the Palearctic, and we examined potential drivers shaping those patterns. We conducted camera trapping surveys in Central Portugal (Southwestern Europe), in eight 16 km2 grids, and analyzed the resulting occurrence data accounting for imperfect detection. Our analysis revealed a preference of the red fox for native vegetation over non-native plantations and avoidance of areas with higher human disturbance. Our data suggest that the current structure of exotic plantations can have a negative impact on species occurrence, even for generalist and resilient species such as the red fox. By gaining insight into landscape structures that promotes fox occupancy, our research can contribute to the development and implementation of more integrative management measures aiming to promote the presence and conservation of mesocarnivores in Eucalyptus dominated landscapes while ensuring sustainable exploitation of these plantations.info:eu-repo/semantics/acceptedVersio