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With habitat loss and fragmentation having become two of the major threats to the viability of species, the question of how to manage landscapes for species conservation has attracted much attention. In this context, the planning of stepping stones has been proposed to increase connectivity in fragmented landscapes. We present a simulation study with a neutral landscape approach to assess the effects of stepping stones on colonization success. To that end, we used a spatially explicit, calibrated population model of the European lynx (Lynx lynx) coupled with structured landscapes, in which we could control the landscape parameters of dispersal habitat coverage and contagion, as well as the number and size of stepping stones available for breeding. In general, we found that colonization success increased with increasing habitat coverage but decreased with increasing habitat contagion, while the introduction of stepping stones had significant effects in critical situations. Especially at low to medium dispersal habitat coverage and high disperser mortality, stepping stones had a positive effect on colonization success when they were large enough to produce new dispersers, but negative effects when they were small and located in a way that dispersers would be distracted from more suitable breeding habitat patches. The latter clearly constituted a shading effect and argues for a thorough consideration of the trade-offs related to stepping stone size and location when implementing stepping stones as a conservation measure, especially when the number of individuals of conservation concern is low.

Animal response to landscape heterogeneity directs dispersal and affects connectivity between populations. Topographical heterogeneity is a major source of landscape heterogeneity, which is rarely studied in the contexts of movement, dispersal, or connectivity. The current study aims at characterizing and quantifying the impacts of topography on landscape connectivity. We focus on ‘hilltopping’ behavior in butterflies, a dispersal-like behavior where males and virgin females ascend to mountain summits and mate there. Our approach integrates three elements: an individual-based model for simulating animal movements across topographically heterogeneous landscapes; a formula for the accessibility of patches in homogenous landscapes; and a graphical analysis of the plots of the simulation-based vs. the formula-based accessibility values. We characterize the functional relationship between accessibility values and landscape structure (referred to as ‘accessibility patterns’) and analyze the influence of two factors: the intensity of the individuals’ response to topography, and the level of topographical noise. We show that, despite the diversity of topographical landscapes, animal response to topography results in the formation of two, quantifiable accessibility patterns. We term them ‘effectively homogeneous’ and ‘effectively channeled’. The latter, in which individuals move toward a single summit, prevails over a wide range of behavioral and spatial parameters. Therefore, ‘channeled’ accessibilities may occur in a variety of landscapes and contexts. Our work provides novel tools for understanding and predicting accessibility patterns in heterogeneous landscapes. These tools are essential for linking movement behavior, movement patterns and connectivity. We also present new insights into the practical value of ecologically scaled landscape indices.

Metapopulation models are frequently used for analysing species–landscape interactions and their effect on structure and dynamic of populations in fragmented landscapes. They especially support a better understanding of the viability of metapopulations. In such models, the processes determining metapopulation viability are often modelled in a simple way. Animals’ dispersal between habitat fragments is mostly taken into account by using a simple dispersal function that assumes the underlying process of dispersal to be random movement. Species-specific dispersal behaviour such as a systematic search for habitat patches is likely to influence the viability of a metapopulation. Using a model for metapopulation viability analysis, we investigate whether such specific dispersal behaviour affects the predictions of ranking orders among alternative landscape configurations rated regarding their ability to carry viable metapopulations. To incorporate dispersal behaviour in the model, we use a submodel for the colonisation rates which allows different movement patterns to be considered (uncorrelated random walk, correlated random walk with various degrees of correlation, and loops). For each movement pattern, the landscape order is determined by comparing the resulting mean metapopulation lifetime Tm of different landscape configurations. Results show that landscape orders can change considerably between different movement patterns. We analyse whether and under what circumstances dispersal behaviour influences the ranking orders of landscapes. We find that the ‘competition between patches for migrants’ – i.e. the fact that dispersers immigrating into one patch are not longer available as colonisers for other patches – is an important factor driving the change in landscape ranks. The implications of our results for metapopulation modelling, planning and conservation are discussed.

Dispersal has been shown to be a key determinant of spatially structured populations. One crucial aspect is predicting patch accessibility: the probability rij of a certain patch j being reached by individuals starting at another patch i. Patch accessibility rij depends on both the landscape structure and the individuals’ dispersal behaviour. To investigate the effects of these factors on rij, we developed a simulation model focusing on animal dispersal. Our model analyses show that there is an important intrinsic effect of the interplay between landscape structure and dispersal behaviour on patch accessibility: the competition between patches for migrants. We derive a formula for patch accessibility. This formula is very simple because it just takes distances into account: not only the distance between start patch and target patch, but also between the start patch and all the other patches in the landscape. Despite its simplicity, the formula is able to cover effects such as the competition for migrants. The formula was found to have high predictive power for a variety of movement behaviours (random walk with various degrees of correlation, Archimedean spirals and loops) in any given landscape. The formula can be interpreted as a generic function for patch accessibility for further population dynamics analyses. It also delivers insights into the consequences of dispersal in fragmented landscapes.

The role of spatial configuration for metapopulation survival is analyzed by using a stochastic metapopulation model. This model reveals conditions which must be satisfied by the species' ecology and the landscape settings before a metapopulation can persist over a long term. Taking this as a basis, initial rules of thumb for landscape management are deduced. The following results are highlighted: (1) the critical correlation length dc of the extinction processes determines a spatial scale of the metapopulation dynamics. (2) Only species with a dispersal range dr above the correlation length dc are able to benefit from landscape management at all. (3) A certain metapopulation can only persist over a long term if no patch is inside the range of correlation of another one. (4) There is a hierarchy of importance in the characteristics of a spatial configuration (scale and type) and, hence, in the scopes of landscape management. To conclude, some general consequences for supporting species survival by management are discussed. Some prospects concerning the use of models for decision support in landscape planning are discussed.