Ecography
Understanding geographic call variation can resolve evolutionary and behavioural questions, yet the factors influencing divergent acoustic signals remain poorly understood in mammals. We explored call variation between collared pikas in Yukon and Alaska and American pikas in Alberta, and between individuals within a population of collared pikas. Classification trees were used to determine the extent...
Much research has centered on determining which habitat model best predicts species occurrence. However, previous work typically used data sets that are inherently biased for evaluation. The use of simulated data provides a way of testing model performance using un‐biased data where the true relationships between species occurrence and population processes are predefined using sound ecological theory...
Understanding patterns of species richness at broad geographic extents remains one of the most challenging yet necessary scientific goals of our time. Many hypotheses have been proposed to account for spatial variation in species richness; among them, environmental determinants have played a central role. In this study, we use data on regional bat species richness in the New World to study redundancy...
Understanding how marine top predators exploit their environment is a central topic in marine ecology. Among all methodologies used to investigate this part of ecology, electronic devices are very useful to track animals' movements and foraging habitats, but they do not provide any dietary information. Stable isotopes provide information on trophic levels but remain imprecise to identify small spatial‐scale...
Amphibian chytridiomycosis (caused by Batrachochytrium dendrobatis; Bd) was first identified in 1998 and has since been implicated in numerous amphibian declines worldwide. Most researchers have since investigated broad‐scale geographic and taxonomic occurrences of the pathogen in tropical lotic or cool montane systems. In this study, we analyzed how environmental factors, land use practices, and...
Assembly rules have been difficult to observe partly because species interactions vary with resource availability, the amount of disturbance, and species richness. Using bird survey data from two years in five regions of SE Australia (463 sites), we tested six predictions from assembly rules theory. We developed generalised linear models for all pair‐wise species comparisons within a region, after...
Anthropogenic fragmentation of habitat and populations is recognized as one of the most important factors influencing loss of biodiversity. Since it is difficult to quantify demographic parameters in small populations, we need alternative methods to elucidate important factors affecting the viability of local populations. The Fennoscandian arctic fox inhabits a naturally fragmented alpine tundra environment,...
Measuring rates of spread during biological invasions is important for predicting where and when invading organisms will spread in the future as well as for quantifying the influence of environmental conditions on invasion speed. While several methods have been proposed in the literature to measure spread rates, a comprehensive comparison of their accuracy when applied to empirical data would be problematic...
In this paper, we investigated the patterns of habitat use in three sibling species of larks: the Thekla lark Galerida theklae which is sympatric with either of two parapatric species of crested larks (G. macrorhyncha replacing G. cristata in arid areas of Morocco). Specifically, we addressed the following questions: 1) do species show niche conservatism in space (France vs Morocco) and time (breeding...
The range expansion of organisms towards higher latitudes and altitudes is often limited by colder temperatures and the shorter growth season. In parasites, survival outside the host is most likely to affect their potential establishment in novel environments. We conducted a large scale transplant experiment to predict the potential spread of the deer ked Lipoptena cervi (Diptera: Hippoboscidae),...
Fluctuating populations are frequently demonstrated to co‐vary in abundance over space, but the dynamics of coupling between populations that gives rise to this synchrony are poorly understood. Synchrony may arise through coupling that is weak and continuous, but in populations that cycle with a characteristic period, synchrony can be maintained through stronger coupling that acts only intermittently...
During the 20th century, forestry practices has adversely affected lichen‐rich habitats. Mat‐forming lichens are important components of the vegetation of boreal and arctic ecosystems and are the main reindeer forage during the winter. To support the long‐term management of lichens in such habitats we developed models for predicting the growth of two common species. The lichens were transplanted across...
Patch isolation resulting from habitat loss and fragmentation generally has detrimental effects on associated species. Peatlands may be especially sensitive to such effects because peat mining results in drastic changes in the hydrology of natural remnants. This study aimed to assess the efficiency of conservation zones surrounding ponds in mined bogs for two taxa: songbirds and odonates. We compared...
Co‐existence of species has been a central debate in ecology for decades but the mechanisms that allow co‐existence are still heatedly disputed. The main paradigms have shifted among the importance of competition, predation and abiotic conditions as determinants of community structure. Differential habitat selection is considered to reduce competition and hence allow co‐existence. Our goal was to...
Although nested species subset patterns and mechanisms promoting them have constituted the focus of a considerable research effort, little attention has been paid to the role of seasonality in generating or moderating these patterns. I conducted monthly censuses of 130 urban parks in the city of Valencia throughout an annual cycle to assess whether seasonality influenced nested patterns of bird species...
Parasite species richness is a fundamental characteristic of host species and varies substantially among host communities. Hypotheses aiming to explain observed patterns of richness are numerous, and none is universal. In this study, we use tapeworm parasites of elasmobranch fishes to examine the phylogenetic and environmental influences on the variation in species richness for this specific system...
Fragmentation theory predicts that population persistence should be positively correlated with the size of habitat fragments. The patterns of occurrence of many species are consistent with this prediction, but the demographic processes that determine how species respond to fragmentation are poorly understood. In addition, habitat quality may interact with fragment size as an influence on demographic...
Species–energy theory posits that energy availability regulates population sizes, extinction rates and ultimately species richness. This theory has focused mostly on total energy as a measure of energy availability. However, because energy variation can also influence population sizes and extinction rates, species–energy theory should arguably consider simultaneously both total energy and its variation...
This study aimed at comparing six patch connectivity measures by fitting them to field data. We used occupancy data for eight beetle and two pseudoscorpion species from 281 hollow oaks in southeast Sweden. Species occupancy was modelled in relation to tree characteristics and one measure of patch connectivity at a time. For each connectivity measure we searched for the spatial scale that generated...
Imminent shifts in environmental parameters due to climatic change might have profound ramifications for wetlands listed under the Ramsar convention. Although the exact mechanisms by which global change will affect these systems are not known, models that simulate component drivers, particularly at a broad spatial scale, can nevertheless allow for more informed conservation decision making. Such general...