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Abstract Habitat selection is strongly scale‐dependent, and inferring the characteristic scale at which an organism responds to environmental variation is necessary to obtain reliable predictions. The occupancy framework is frequently used to model species distribution with the advantage of accounting for imperfect observation, but occupancy studies typically do not define the characteristic scale of the modelled variables. We used camera trap data from winter wildlife surveys in the Swiss part of the Jura Mountains to model occupancy of wild boar (Sus scrofa) and roe deer (Capreolus capreolus). We used a three‐step approach: (1) first, we identified factors influencing detectability; (2) second, we optimized the characteristic scale of each candidate explanatory variable; and (3) third, we fit multivariable, multiscale occupancy models in relation to land cover, human presence and topography. Wild boar occupancy was mainly influenced by the interaction between elevation within 2500 m and the proportion of forested areas within a 2500 m, with a nonsignificant additional effect of the interaction between ruggedness within 1900 m and the proportion of forested areas within 2500 m as well as the distance to urban areas. Roe deer occupancy was mainly associated with the interaction between ruggedness within 900 m and the proportion of open landscape within 900 m, with an additional nonsignificant effect of the interaction between elevation within 1500 m and the proportion of open landscape within 900 m as well as the distance to urban areas. Incorporating scale optimization in occupancy modelling of camera trap data can greatly improve the understanding of species‐environment relationships by combining the possibility of occupancy models to correct for detection bias and simultaneously allowing to infer the characteristic scale at which certain factors influence the distribution of the organisms studied.

Habitat selection is strongly scale‐dependent, and inferring the characteristic scale at which an organism responds to environmental variation is necessary to obtain reliable predictions. The occupancy framework is frequently used to model species distribution with the advantage of accounting for imperfect observation, but occupancy studies typically do not define the characteristic scale of the modelled variables. We used camera trap data from winter wildlife surveys in the Swiss part of the Jura Mountains to model occupancy of wild boar (Sus scrofa) and roe deer (Capreolus capreolus). We used a three‐step approach: (1) first, we identified factors influencing detectability; (2) second, we optimized the characteristic scale of each candidate explanatory variable; and (3) third, we fit multivariable, multiscale occupancy models in relation to land cover, human presence and topography. Wild boar occupancy was mainly influenced by the interaction between elevation within 2500 m and the proportion of forested areas within a 2500 m, with a nonsignificant additional effect of the interaction between ruggedness within 1900 m and the proportion of forested areas within 2500 m as well as the distance to urban areas. Roe deer occupancy was mainly associated with the interaction between ruggedness within 900 m and the proportion of open landscape within 900 m, with an additional nonsignificant effect of the interaction between elevation within 1500 m and the proportion of open landscape within 900 m as well as the distance to urban areas. Incorporating scale optimization in occupancy modelling of camera trap data can greatly improve the understanding of species‐environment relationships by combining the possibility of occupancy models to correct for detection bias and simultaneously allowing to infer the characteristic scale at which certain factors influence the distribution of the organisms studied. [ABSTRACT FROM AUTHOR]

Our knowledge of the impact of landscape fragmentation on gene flow patterns is mainly drawn from tropical and temperate ecosystems, where landscape features, such as the distance of a tree to the forest edge, drive connectivity and mating patterns. Yet, the structure of arid and semiarid plant communities – with open canopies and a scattered distribution of trees – differs greatly from those that are well‐characterized in the literature. As a result, we ignore whether the documented consequences of landscape fragmentation on plant mating and gene flow patterns also hold for native plant communities in arid and semiarid regions. We investigated the relative contribution of plant traits, pollinator activity, and individual neighbourhood in explaining variation in mating and gene flow patterns of an insect‐pollinated semiarid arborescent shrub, Ziziphus lotus, at three sites embedded in highly altered agriculture landscapes. We used 14 SSRs, seed paternity analyses, and individual mixed effect mating models (MEMMi) to estimate the individual mating variables and the pollen dispersal kernel at each site. Individual spatial location, flower density, and floral visitation rate explained most of the variation of mating variables. Unexpectedly, individual correlated paternity was very low and shrubs surrounded by the most degraded matrix exhibited an increased fraction of pollen immigration and a high effective number of pollen donors per mother shrub. Overall, our results reveal that an active pollinator assemblage ensures highly efficient mating, and maintains pollen‐mediated gene flow and notable connectivity levels, even in highly altered landscapes, potentially halting genetic isolation within and between distant sites. [ABSTRACT FROM AUTHOR]

Drought-induced episodes of forest die-off are being reported world-wide, and recent evidence shows that increases in temperature due to climate change are contributing to this decline. Several ecological mechanisms have been invoked at the plant level to explain the vulnerability of trees to this widespread drought-induced mortality., Apart from ecological factors, some genetic factors might also influence population responses to disturbances: it has been reported, for example, that genetic diversity enhances population resilience through genotypic complementarity, whereas genetic relatedness between conspecific individuals exerts a negative influence on variations in fecundity. However, we lack empirical data that prove any functional relationship between levels of individual inbreeding or kinship and patterns of drought-induced forest die-off resulting from field conditions., Here, we investigated the role of ecological, phenotypic and genetic factors in determining the response of trees to prolonged drought conditions. We focused on populations of the small tree Juniperus phoenicea L. that recently experienced severe drought-induced die-off in semi-arid woodlands from central Spain., We correlated mean individual inbreeding ( f) and mean kinship between individuals within a plot ( f ij) with remaining green plant canopy and crop size. We found that f was negatively correlated with plant performance, whereas f ij was not. Healthier canopy also tended to correspond with large plants and neighbourhoods dominated by trees and shrubs, suggesting a role for facilitative interactions and microsite heterogeneity. Accordingly, the probability of severe damage increased linearly with f, and individuals growing in open habitats with f values > 0·625 only had 15% chance of remaining unaffected after a period of prolonged drought., We show that both vegetative and reproductive responses to prolonged drought episodes are determined by multiple factors, including individual inbreeding. Therefore, any fuller understanding of phenomena such as drought-induced forest die-off needs to incorporate the contribution of individual genetic variations in conjunction with plant-plant interactions. [ABSTRACT FROM AUTHOR]

The mutual reinforcement of multiple drivers of global change erodes ecosystem services and accelerates plant population decline worldwide. This is particularly the case for island ecosystems where anthropogenic activity has imperilled insular floras for centuries. Different hypotheses have put forward the combined effects of environmental shifts and genetic factors in driving fecundity decline in threatened populations. In this study, we combined population genetic tools and structural equation models to test the eco-genetic mediation hypothesis, that the environmental conditions influence genetic variation, which in turn affects plant fitness. Our study species is Juniperus cedrus , an endangered juniper species endemic to the Canary Islands. Juniper woodlands have been depleted since the arrival of human inhabitants confined extant populations to marginal lands. More recently, long-distance dispersers have been extirpated from the study area, potentially eliminating connectivity among fragmented populations. We expected strong intrapopulation subdivision and high levels of inbreeding and kinship that should negatively affect individual fitness. We found evidence of population subdivision into several mating neighbourhoods ( K = 13), some of them highly inbred. However, contrary to our expectations, neither inbreeding nor mean kinship mediated a population response to environmental factors. Our results suggest three remedial actions to reverse the declining demographic trends: (i) re-establish native vegetation to ameliorate local environmental conditions; (ii) restore dispersal services to increase connectivity; and (iii) monitor fitness decline to identify lagged effects associated with deforestation. Overall, this study shows that structural equation models combined with population genetic techniques are suitable tools to identify high-order effects among multiple drivers of global change that underlie forest decline. [ABSTRACT FROM AUTHOR]

Highlights: [•] A secondary succession model based on Ellenberg indicator values is proposed. [•] For each tree its actual vigour and height are calculated within annual time steps. [•] Each tree is appointed with the ecological neighbourhood, represented by a circle. [•] If two neighbourhoods intersect the tree with lower vigour eventually dies. [•] Tree competition triggers the changes in the species composition. [Copyright &y& Elsevier]

The focal species approach to nature conservation provides a method for identifying management actions required to meet the needs of the most vulnerable species in a landscape with respect to the threatening processes responsible for their decline. For each threat, a focal species is identified as the one with the most critical requirement pertaining to the threat. With multiple threats, the resulting suite of focal species can be regarded as a “focal community”, whose combined needs are used to address a range of management actions. In this paper, the critical requirements of a focal community of resident land birds are identified with respect to the threats arising from the loss, fragmentation and degradation of habitat in the central wheat-belt of Western Australia. This knowledge of their critical requirements is then used to guide a landscape design procedure for the enhancement of bird habitat in the Gabbi Quoi Quoi sub-catchment of Western Australia. The landscape design procedure is framed against the concept of the ecological neighbourhood, where the necessary size, spatial arrangement, area of influence and connectivity of existing landscape elements are used as a starting point for habitat restoration and re-vegetation. [Copyright &y& Elsevier]

The population are of flowering shoots of the perennial herb, Saxifraga hirculus, reaches a max. of 134 m and an overall density of flowers/m of 11.4. The flower is mainly visited by a syrphid sp., Eurimyia lineata, and to a lesser extent by another syrphid Neoscia tenur, a moth, Zygaena trifolii, and a fungus gnat, Asindulum nigrum. The distribution of the interfloral flight distance is leptokurtic. The mean flight distance of the visitors is 101 cm. 10% of the flights are much longer (2-8 m: cross-flower patch, and about 20 m: cross-population flights). If they are not included, the mean of flights (<1.7 m) becomes 28 cm. These flights become shorter with increasing flower density. The visitors do not have a nearest-neighbour foraging pattern. They visit on average the 8th nearest neighbour. The distribution of flight directions is uniform. Seed dispersal distances have a leptokurtic distribution and a mean dispersal distance of 13 cm. The ecological neighbourhood area is 66.4 m and 64.9 m assuming normality and allowing for leptokurtosis. Z. trifolii with its large proportion of long flights increases the size of the neighbourhood area considerably. The mean flight distance (<1.7 m) is correlated with neighbourhood area. The evolutionary impact of moths and butterflies to plant population structure is stressed. [ABSTRACT FROM AUTHOR]