Dispersal influences genetic and acoustic spatial structure for both males and females in a tropical songbird

Animals exhibit diverse dispersal strategies, including sex‐biased dispersal, a phenomenon common in vertebrates. Dispersal influences the genetic structure of populations as well as geographic variation in phenotypic traits. Patterns of spatial genetic structure and geographic variation may vary between the sexes whenever males and females exhibit different dispersal behaviors. Here, we examine dispersal, spatial genetic structure, and spatial acoustic structure in Rufous‐and‐white Wrens, a year‐round resident tropical bird. Both sexes sing in this species, allowing us to compare acoustic variation between males and females and examine the relationship between dispersal and song sharing for both sexes. Using a long‐term dataset collected over an 11‐year period, we used banding data and molecular genetic analyses to quantify natal and breeding dispersal distance in Rufous‐and‐white Wrens. We quantified song sharing and examined whether sharing varied with dispersal distance, for both males and females. Observational data and molecular genetic analyses indicate that dispersal is female‐biased. Females dispersed farther from natal territories than males, and more often between breeding territories than males. Furthermore, females showed no significant spatial genetic structure, consistent with expectations, whereas males showed significant spatial genetic structure. Overall, natal dispersal appears to have more influence than breeding dispersal on spatial genetic structure and spatial acoustic structure, given that the majority of breeding dispersal events resulted in individuals moving only short distances. Song sharing between pairs of same‐sex animals decreases with the distance between their territories for both males and females, although males exhibited significantly greater song sharing than females. Lastly, we measured the relationship between natal dispersal distance and song sharing. We found that sons shared fewer songs with their fathers the farther they dispersed from their natal territories, but that song sharing between daughters and mothers was not significantly correlated with natal dispersal distance. Our results reveal cultural differences between the sexes, suggesting a relationship between culture and sex‐biased dispersal.     

Genetic diversity and sex‐bias dispersal of plateau pika in Tibetan plateau

Dispersal is an important aspect in organism's life history which could influence the rate and outcome of evolution of organism. Plateau pika is the keystone species in community of grasslands in Tibetan Plateau. In this study, we combine genetic and field data to character the population genetic pattern and dispersal dynamics in plateau pika (Ochotona curzoniae). Totally, 1,352 individual samples were collected, and 10 microsatellite loci were analyzed. Results revealed that plateau pika possessed high genetic diversity and inbreeding coefficient in a fine‐scale population. Dispersal distance is short and restricted in about 20 m. An effective sex‐biased dispersal strategy is employed by plateau pika: males disperse in breeding period for mating while females do it after reproduction for offspring and resource. Inbreeding avoiding was shown as the common driving force of dispersal, together with the other two factors, environment and resource. In addition, natal dispersal is female biased. More detailed genetic analyzes are needed to confirm the role of inbreeding avoidance and resource competition as ultimate cause of dispersal patterns in plateau pika.     

Sex biased natal dispersal in a closed, saturated population of Seychelles warblers Acrocephalus sechellensis

The distances that individuals disperse, from their natal site to the site of first breeding and between breeding sites, have important consequences for the dynamics and genetic structure of a population. Nearly all previous studies on dispersal have the problem that, because the study area encompassed only a part of the population, emigration may have been confounded with mortality. As a result long-distance dispersers may have been overlooked and dispersal data biased towards short distances. By studying a virtually closed population of Seychelles warblers Acrocephalus sechellensis we obtained almost unbiased results on several aspects of dispersal. As in the majority of other avian species, natal dispersal distance was female biased in the Seychelles warbler. Female offspring also forayed further from the natal territory in search of breeding vacancies than male offspring. The sex bias in natal dispersal distance did, however, depend on local breeding density. In males, dispersal distance decreased as the number of territories bordering the natal territory increased, while in females, dispersal distance did not vary with local density. Dispersal by breeders was rare and, unlike in most species, distances did not differ between the sexes. We argue that our results favour the idea that the sex bias in natal dispersal distance in the Seychelles warbler is due to inbreeding avoidance and not resource competition or intrasexual competition for mates.     

Developing approaches for linear mixed modeling in landscape genetics through landscape‐directed dispersal simulations

Dispersal can impact population dynamics and geographic variation, and thus, genetic approaches that can establish which landscape factors influence population connectivity have ecological and evolutionary importance. Mixed models that account for the error structure of pairwise datasets are increasingly used to compare models relating genetic differentiation to pairwise measures of landscape resistance. A model selection framework based on information criteria metrics or explained variance may help disentangle the ecological and landscape factors influencing genetic structure, yet there are currently no consensus for the best protocols. Here, we develop landscape‐directed simulations and test a series of replicates that emulate independent empirical datasets of two species with different life history characteristics (greater sage‐grouse; eastern foxsnake). We determined that in our simulated scenarios, AIC and BIC were the best model selection indices and that marginal R² values were biased toward more complex models. The model coefficients for landscape variables generally reflected the underlying dispersal model with confidence intervals that did not overlap with zero across the entire model set. When we controlled for geographic distance, variables not in the underlying dispersal models (i.e., nontrue) typically overlapped zero. Our study helps establish methods for using linear mixed models to identify the features underlying patterns of dispersal across a variety of landscapes.     

Fine‐scale genetic structure reflects sex‐specific dispersal strategies in a population of sociable weavers (Philetairus socius)

Dispersal is a critical driver of gene flow, with important consequences for population genetic structure, social interactions and other biological processes. Limited dispersal may result in kin‐structured populations in which kin selection may operate, but it may also increase the risk of kin competition and inbreeding. Here, we use a combination of long‐term field data and molecular genetics to examine dispersal patterns and their consequences for the population genetics of a highly social bird, the sociable weaver (Philetairus socius), which exhibits cooperation at various levels of sociality from nuclear family groups to its unique communal nests. Using 20 years of data, involving capture of 6508 birds and 3151 recaptures at 48 colonies, we found that both sexes exhibit philopatry and that any dispersal occurs over relatively short distances. Dispersal is female‐biased, with females dispersing earlier, further, and to less closely related destination colonies than males. Genotyping data from 30 colonies showed that this pattern of dispersal is reflected by fine‐scale genetic structure for both sexes, revealed by isolation by distance in terms of genetic relatedness and significant genetic variance among colonies. Both relationships were stronger among males than females. Crucially, significant relatedness extended beyond the level of the colony for both sexes. Such fine‐scale population genetic structure may have played an important role in the evolution of cooperative behaviour in this species, but it may also result in a significant inbreeding risk, against which female‐biased dispersal alone is unlikely to be an effective strategy.     

Similarity in temporal variation in sex‐biased dispersal over short and long distances in the dark‐eyed junco,Junco hyemalis

Patterns of sex‐biased dispersal (SBD) are typically consistent within taxa, for example female‐biased in birds and male‐biased in mammals, leading to theories about the evolutionary pressures that lead to SBD. However, generalizations about the evolution of sex biases tend to overlook that dispersal is mediated by ecological factors that vary over time. We examined potential temporal variation in between‐ and within‐population dispersal over an 11‐year period in a bird, the dark‐eyed junco (Junco hyemalis). We measured between‐population dispersal patterns using genetic assignment indices and found yearly variation in which sex was more likely to have immigrated. When we measured within‐population spatial genetic structure and mark–recapture dispersal distances, we typically found yearly SBD patterns that mirrored between‐population dispersal, indicating common eco‐evolutionary causes despite expected differences due to the scale of dispersal. However, in years without detectable between‐population sex biases, we found genetic similarity between nearby males within our population. This suggests that, in certain circumstances, ecological pressures may act on within‐population dispersal without affecting dispersal between populations. Alternatively, current analytical tools may be better able to detect within‐population SBD. Future work will investigate potential causes of the observed temporal variation in dispersal patterns and whether they have greater effects on within‐population dispersal.     

Biased dispersal of Metrioptera bicolor,a wing dimorphic bush‐cricket

In the highly fragmented landscape of central Europe, dispersal is of particular importance as it determines the long‐term survival of animal populations. Dispersal not only secures the recolonization of patches where populations went extinct, it may also rescue small populations and thus prevent local extinction events. As dispersal involves different individual fitness costs, the decision to disperse should not be random but context‐dependent and often will be biased toward a certain group of individuals (e.g., sex‐ and wing morph‐biased dispersal). Although biased dispersal has far‐reaching consequences for animal populations, immediate studies of sex‐ and wing morph‐biased dispersal in orthopterans are very rare. Here, we used a combined approach of morphological and genetic analyses to investigate biased dispersal of Metrioptera bicolor, a wing dimorphic bush‐cricket. Our results clearly show wing morph‐biased dispersal for both sexes of M. bicolor. In addition, we found sex‐biased dispersal for macropterous individuals, but not for micropters. Both, morphological and genetic data, favor macropterous males as dispersal unit of this bush‐cricket species. To get an idea of the flight ability of M. bicolor, we compared our morphological data with that of Locusta migratoria and Schistocerca gregaria, which are very good flyers. Based on our morphological data, we suggest a good flight ability for macropters of M. bicolor, although flying individuals of this species are seldom observed.     

Local density and group size interacts with age and sex to determine direction and rate of social dispersal in a polygynous mammal

Movement away from an area or social group in response to increasing density (density‐dependent dispersal) is known for most species; why it evolves is fundamental to our understanding of ecology and evolution. However, we have yet to fully appreciate how individuals of varying conditions (e.g., age and sex) might differently consider effects of density (quorum) when deciding to disperse or not, and scale dependence in their sense of quorum. We tracked movements of all individuals of a naturalized population of feral horses (Equus ferus caballus; Sable Island National Park Reserve, Nova Scotia, Canada) during a period of rapid population growth (N increased from 375 to 484 horses from 2008 to 2010). Permanent dispersal from breeding groups (bands) was positively density dependent for all age and sex categories with respect to local density (horses/km², bounded by the 99th percentile of individual movements [8000 m]), but was negatively and positively density dependent for males and females, respectively, in relation to group (band) size. Dispersal was generally female biased, with the exception of foals which moved with their mothers (no sex effect), and for yearlings and subadults when band sizes were smaller than average, in which case males dispersed at higher rates than females. Dispersal distance was positively related to local density. We conclude that dispersal rate can be both positively and negatively density dependent for feral horses, contingent on the state of individuals and the scale at which quorum with respect to choosing to disperse or not is assessed. Scale effects and interactions of density‐dependent and sex‐ and age‐biased dispersal may have both ecological and evolutionary consequences through effects on resource and mate competition.     

Limited influence of local and landscape factors on finescale gene flow in two pond‐breeding amphibians

Dispersal and gene flow within animal populations are influenced by the composition and configuration of the landscape. In this study, we evaluated hypotheses about the impact of natural and anthropogenic factors on genetic differentiation in two amphibian species, the spotted salamander (Ambystoma maculatum) and the wood frog (Lithobates sylvaticus) in a commercial forest in central Maine. We conducted this analysis at two scales: a local level, focused on factors measured at each breeding pond, and a landscape level, focused on factors measured between ponds. We investigated the effects of a number of environmental factors in six categories including Productivity, Physical, Land Composition, Land Configuration, Isolation and Location. Embryos were sampled from 56 spotted salamander breeding ponds and 39 wood frog breeding ponds. We used a hierarchical Bayesian approach in the program GESTE at each breeding pond and a random forest algorithm in conjunction with a network analysis between the ponds. We found overall high genetic connectivity across distances up to 17 km for both species and a limited effect of natural and anthropogenic factors on gene flow. We found the null models best explained patterns of genetic differentiation at a local level and found several factors at the landscape level that weakly influenced gene flow. This research indicates multiscale investigations that incorporate local and landscape factors are valuable for understanding patterns of gene flow. Our findings suggest that dispersal rates in this system are high enough to minimize genetic structuring and that current forestry practices do not significantly impede dispersal.     

High gene flow on a continental scale in the polyandrous Kentish plover Charadrius alexandrinus

Gene flow promotes genetic homogeneity of species in time and space. Gene flow can be modulated by sex‐biased dispersal that links population genetics to mating systems. We investigated the phylogeography of the widely distributed Kentish plover Charadrius alexandrinus. This small shorebird has a large breeding range spanning from Western Europe to Japan and exhibits an unusually flexible mating system with high female breeding dispersal. We analysed genetic structure and gene flow using a 427‐bp fragment of the mitochondrial (mtDNA) control region, 21 autosomal microsatellite markers and a Z microsatellite marker in 397 unrelated individuals from 21 locations. We found no structure or isolation‐by‐distance over the continental range. However, island populations had low genetic diversity and were moderately differentiated from mainland locations. Genetic differentiation based on autosomal markers was positively correlated with distance between mainland and each island. Comparisons of uniparentally and biparentally inherited markers were consistent with female‐biased gene flow. Maternally inherited mtDNA was less structured, whereas the Z‐chromosomal marker was more structured than autosomal microsatellites. Adult males were more related than females within genetic clusters. Taken together, our results suggest a prominent role for polyandrous females in maintaining genetic homogeneity across large geographic distances.     

Gene flow and natal dispersal in the Siberian flying squirrel based on direct and indirect data

Dispersal is a key determinant of the evolution and ecology of species. For a comprehensive picture of dispersal, a combination of both field observations and indirect genetic measures are required, as both of these have strengths that may mitigate the other’s limitations. Here, we used microsatellite markers and radio-telemetry data to study dispersal and gene flow in Siberian flying squirrels. Genetic data confirmed our empirical results that dispersal is female biased in the flying squirrel. Female bias in dispersal is exceptional among mammals and in flying squirrels is probably explained by competition for food resources and nesting cavities among mothers and daughters. The individual-level genetic pattern was influenced by isolation by distance. Using this information fairly comparable dispersal distances were derived using indirect data as observed directly with radio telemetry. Thus, our results support the recent conclusion that individual-level genetic data can be useful in inferring dispersal distances for species for which direct data are lacking.     

The new kid on the block: immigrant males win big whereas females pay fitness cost after dispersal

Dispersal is nearly universal; yet, which sex tends to disperse more and their success thereafter depends on the fitness consequences of dispersal. We asked if lifetime fitness differed between residents and immigrants (successful between‐population dispersers) and their offspring using 29 years of monitoring from North American red squirrels (Tamiasciurus hudsonicus) in Canada. Compared to residents, immigrant females had 23% lower lifetime breeding success (LBS), while immigrant males had 29% higher LBS. Male immigration and female residency were favoured. Offspring born to immigrants had 15–43% lower LBS than offspring born to residents. We conclude that immigration benefitted males, but not females, which appeared to be making the best of a bad lot. Our results are in line with male‐biased dispersal being driven by local mate competition and local resource enhancement, while the intergenerational cost to immigration is a new complication in explaining the drivers of sex‐biased dispersal.     

Variation in fine‐scale genetic structure and local dispersal patterns between peripheral populations of a South American passerine bird

The distribution of suitable habitat influences natal and breeding dispersal at small spatial scales, resulting in strong microgeographic genetic structure. Although environmental variation can promote interpopulation differences in dispersal behavior and local spatial patterns, the effects of distinct ecological conditions on within‐species variation in dispersal strategies and in fine‐scale genetic structure remain poorly understood. We studied local dispersal and fine‐scale genetic structure in the thorn‐tailed rayadito (Aphrastura spinicauda), a South American bird that breeds along a wide latitudinal gradient. We combine capture‐mark‐recapture data from eight breeding seasons and molecular genetics to compare two peripheral populations with contrasting environments in Chile: Navarino Island, a continuous and low density habitat, and Fray Jorge National Park, a fragmented, densely populated and more stressful environment. Natal dispersal showed no sex bias in Navarino but was female‐biased in the more dense population in Fray Jorge. In the latter, male movements were restricted, and some birds seemed to skip breeding in their first year, suggesting habitat saturation. Breeding dispersal was limited in both populations, with males being more philopatric than females. Spatial genetic autocorrelation analyzes using 13 polymorphic microsatellite loci confirmed the observed dispersal patterns: a fine‐scale genetic structure was only detectable for males in Fray Jorge for distances up to 450 m. Furthermore, two‐dimensional autocorrelation analyzes and estimates of genetic relatedness indicated that related males tended to be spatially clustered in this population. Our study shows evidence for context‐dependent variation in natal dispersal and corresponding local genetic structure in peripheral populations of this bird. It seems likely that the costs of dispersal are higher in the fragmented and higher density environment in Fray Jorge, particularly for males. The observed differences in microgeographic genetic structure for rayaditos might reflect the genetic consequences of population‐specific responses to contrasting environmental pressures near the range limits of its distribution.     

Landscape genetics of an early successional specialist in a disturbance‐prone environment

Species that specialize in disturbed habitats may have considerably different dispersal strategies than those adapted to more stable environments. However, little is known of the dispersal patterns and population structure of such species. This information is important for conservation because many postfire specialists are at risk from anthropogenic changes to natural disturbance regimes. We used microsatellite markers to assess the effect of landscape variation and recent disturbance history on dispersal by a small mammal species that occupies the early seral stage of vegetation regeneration in burnt environments. We predicted that a postfire specialist would be able to disperse over multiple habitat types (generalist) and not exhibit sex‐biased dispersal, as such strategies should enable effective colonization of spatially and temporally variable habitat. We found significant differentiation between sites that fitted an isolation‐by‐distance pattern and spatial autocorrelation of multilocus genotypes to a distance of 2–3 km. There was no consistent genetic evidence for sex‐biased dispersal. We tested the influence of different habitat‐ and fire‐specific landscape resistance scenarios on genetic distance between individuals and found a significant effect of fire. Our genetic data supported recently burned vegetation having greater conductance for gene flow than unburnt habitat, but variation in habitat quality between vegetation types and occupied patches had no effect on gene flow. Postfire specialists must evolve an effective dispersal ability to move over distances that would ensure access to early successional stage vegetation. Natural disturbance and natural heterogeneity may therefore not influence population genetic structure as negatively as expected.     

Sex‐biased breeding dispersal is predicted by social environment in birds

Sex‐biased dispersal is common in vertebrates, although the ecological and evolutionary causes of sex differences in dispersal are debated. Here, we investigate sex differences in both natal and breeding dispersal distances using a large dataset on birds including 86 species from 41 families. Using phylogenetic comparative analyses, we investigate whether sex‐biased natal and breeding dispersal are associated with sexual selection, parental sex roles, adult sex ratio (ASR), or adult mortality. We show that neither the intensity of sexual selection, nor the extent of sex bias in parental care was associated with sex‐biased natal or breeding dispersal. However, breeding dispersal was related to the social environment since male‐biased ASRs were associated with female‐biased breeding dispersal. Male‐biased ASRs were associated with female‐biased breeding dispersal. Sex bias in adult mortality was not consistently related to sex‐biased breeding dispersal. These results may indicate that the rare sex has a stronger tendency to disperse in order to find new mating opportunities. Alternatively, higher mortality of the more dispersive sex could account for biased ASRs, although our results do not give a strong support to this explanation. Whichever is the case, our findings improve our understanding of the causes and consequences of sex‐biased dispersal. Since the direction of causality is not yet known, we call for future studies to identify the causal relationships linking mortality, dispersal, and ASR.     

The influence of breeding phenology on the genetic structure of four pond‐breeding salamanders

Understanding metapopulation dynamics requires knowledge about local population dynamics and movement in both space and time. Most genetic metapopulation studies use one or two study species across the same landscape to infer population dynamics; however, using multiple co‐occurring species allows for testing of hypotheses related to different life history strategies. We used genetic data to study dispersal, as measured by gene flow, in three ambystomatid salamanders (Ambystoma annulatum , A. maculatum , and A. opacum ) and the Central Newt (Notophthalmus viridescens louisianensis ) on the same landscape in Missouri, USA . While all four salamander species are forest dependent organisms that require fishless ponds to reproduce, they differ in breeding phenology and spatial distribution on the landscape. We use these differences in life history and distribution to address the following questions: (1) Are there species‐level differences in the observed patterns of genetic diversity and genetic structure? and (2) Is dispersal influenced by landscape resistance? We detected two genetic clusters in A. annulatum and A. opacum on our landscape; both species breed in the fall and larvae overwinter in ponds. In contrast, no structure was evident in A. maculatum and N. v. louisianensis , species that breed during the spring. Tests for isolation by distance were significant for the three ambystomatids but not for N. v. louisianensis . Landscape resistance also contributed to genetic differentiation for all four species. Our results suggest species‐level differences in dispersal ability and breeding phenology are driving observed patterns of genetic differentiation. From an evolutionary standpoint, the observed differences in dispersal distances and genetic structure between fall breeding and spring breeding species may be a result of the trade‐off between larval period length and size at metamorphosis which in turn may influence the long‐term viability of the metapopulation. Thus, it is important to consider life history differences among closely related and ecologically similar species when making management decisions.     

Population genetic evidence for sex‐specific dispersal in an inbred social spider

Dispersal in most group‐living species ensures gene flow among groups, but in cooperative social spiders, juvenile dispersal is suppressed and colonies are highly inbred. It has been suggested that such inbred sociality is advantageous in the short term, but likely to lead to extinction or reduced speciation rates in the long run. In this situation, very low levels of dispersal and gene flow among colonies may have unusually important impacts on fitness and persistence of social spiders. We investigated sex‐specific differences in dispersal and gene flow among colonies, as reflected in the genetic structure within colonies and populations of the African social spider Stegodyphus dumicola Pocock, 1898 (Eresidae). We used DNA fingerprinting and mtDNA sequence data along with spatial mapping of colonies to compare male and female patterns of relatedness within and among colonies at three study sites. Samples were collected during and shortly after the mating season to detect sex‐specific dispersal. Distribution of mtDNA haplotypes was consistent with proliferation of social nests by budding and medium‐ to long‐distance dispersal by ballooning females. Analysis of molecular variance and spatial autocorrelation analyses of AFLPs showed high levels of genetic similarity within colonies, and STRUCTURE analyses revealed that the number of source populations contributing to colonies ranged from one to three. We also showed significant evidence of male dispersal among colonies at one site. These results support the hypothesis that in social spiders, genetic cohesion among populations is maintained by long‐distance dispersal of female colony founders. Genetic diversity within colonies is maintained by colony initiation by multiple dispersing females, and adult male dispersal over short distances. Male dispersal may be particularly important in maintaining gene flow among colonies in local populations.     

Factors influencing and consequences of breeding dispersal and habitat choice in female grey seals (<Emphasis Type="Italic">Halichoerus grypus</Emphasis>) on Sable Island,Nova Scotia

Selection of breeding location can influence reproductive success and fitness. Breeding dispersal links habitat use and reproduction. This study investigated factors affecting breeding dispersal and its reproductive consequences in grey seals (Halichoerus grypus) on Sable Island, Nova Scotia. Breeding dispersal distance was determined in 692 individually marked, known-age female grey seals observed from 2004 to 2014. We used generalized linear mixed-effects models to test hypotheses concerning environmental and demographic factors influencing breeding dispersal distance and the consequences of dispersal distance on offspring weaning mass. Grey seal females rarely exhibited fidelity to previous breeding sites. Median dispersal distance between years was 5.1 km. Only 2.9% of females returned to a previous breeding site. Breeding dispersal distance was affected by parity and density, but effects were small and are presumably of no biological significance. Variation in dispersal distance among adult females was large. Dispersal distance had no significant influence on offspring weaning mass; however, as previously found, pup sex and maternal age did. Although breeding location was not important, heavier pups were born in habitats with no tidal or storm-surge influence indicating that breeding habitat type did influence offspring size at weaning. The lack of site fidelity in grey seals on Sable Island is associated with an unpredictable and changing landscape (sand dunes) that could make it difficult for females to locate previous breeding locations. Although breeding location within habitat type had small consequences on offspring weaning mass, we detected no evidence that breeding site selection within the habitat had consequences to females.     

Dispersal distances predict subspecies richness in birds

Dispersal ability has been hypothesized to reduce intraspecific differentiation by homogenizing populations. On the other hand, long‐distance dispersers may have better opportunities to colonize novel habitats, which could result in population divergence. Using direct estimates of natal and breeding dispersal distances, we investigated the relationship between dispersal distances and: (i) population differentiation, assessed as subspecies richness; (ii) ecological plasticity, assessed as the number of habitats used for breeding; and (iii) wing size, assessed as wing length. The number of subspecies was negatively correlated with dispersal distances. This was the case also after correcting for potential confounding factors such as migration and similarity due to common ancestry. Dispersal was not a good predictor of ecological plasticity, suggesting that long‐distance dispersers do not have more opportunities to colonize novel habitats. Residual wing length was related to natal dispersal, but only for sedentary species. Overall, these results suggest that dispersal can have a homogenizing effect on populations and that low dispersal ability might promote speciation.     

Beyond the landscape: Resistance modelling infers physical and behavioural gene flow barriers to a mobile carnivore across a metropolitan area

Urbanization affects key aspects of wildlife ecology. Dispersal in urban wildlife species may be impacted by geographical barriers but also by a species’ inherent behavioural variability. There are no functional connectivity analyses using continuous individual‐based sampling across an urban‐rural continuum that would allow a thorough assessment of the relative importance of physical and behavioural dispersal barriers. We used 16 microsatellite loci to genotype 374 red foxes (Vulpes vulpes) from the city of Berlin and surrounding rural regions in Brandenburg in order to study genetic structure and dispersal behaviour of a mobile carnivore across the urban‐rural landscape. We assessed functional connectivity by applying an individual‐based landscape genetic optimization procedure. Three commonly used genetic distance measures yielded different model selection results, with only the results of an eigenvector‐based multivariate analysis reasonably explaining genetic differentiation patterns. Genetic clustering methods and landscape resistance modelling supported the presence of an urban population with reduced dispersal across the city border. Artificial structures (railways, motorways) served as main dispersal corridors within the cityscape, yet urban foxes avoided densely built‐up areas. We show that despite their ubiquitous presence in urban areas, their mobility and behavioural plasticity, foxes were affected in their dispersal by anthropogenic presence. Distinguishing between man‐made structures and sites of human activity, rather than between natural and artificial structures, is thus essential for better understanding urban fox dispersal. This differentiation may also help to understand dispersal of other urban wildlife and to predict how behaviour can shape population genetic structure beyond physical barriers.