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This review clarifies important points on habitat selection by the Swamp Rat Rattus lutreolus (Rodentia: Muridae), a species that has been the subject of much research in Australia and has provided a useful model for understanding ecological and biological processes. It also provides an opportunity to cite important earlier research, not readily available through electronic search engines, thus bringing it into current literature to avoid its disappearance into Internet obscurity. We comment on some papers in the literature to correct errors detected and to emphasize the importance of due care in all aspects of a research project, including its reporting. We show that both floristic and structural components have been reported as important to an understanding of habitat and microhabitat selection by R. lutreolus and conclude that it is vegetation density that is of paramount importance. Female R. lutreolus are clearly dominant in driving microhabitat selection, occupying the ‘best’ or densest habitats with male R. lutreolus occupying the next best and Pseudomys or other species, where present occupying the remainder. This demonstrates the important role that intraspecific and interspecific competition play in determining habitat selection. Direct predation and the perception of predation risk may also play a role in habitat selection, again perceived to be pushing individuals towards denser vegetation, representing ‘better cover’. Whether these effects operate as bottom-up or top-down needs careful consideration. Climatic variables, such as ENSO-affecting productivity, and related variables such as temperature and humidity may also play important roles in habitat selection, as can disturbance effects such as wildfire. The relative importance of all of these potential determining factors may vary from place to place, particularly when climatic clines are involved. [ABSTRACT FROM AUTHOR]

1. The biases and shortcomings of stepwise multiple regression are well established within the statistical literature. However, an examination of papers published in 2004 by three leading ecological and behavioural journals suggested that the use of this technique remains widespread: of 65 papers in which a multiple regression approach was used, 57% of studies used a stepwise procedure. 2. The principal drawbacks of stepwise multiple regression include bias in parameter estimation, inconsistencies among model selection algorithms, an inherent (but often overlooked) problem of multiple hypothesis testing, and an inappropriate focus or reliance on a single best model. We discuss each of these issues with examples. 3. We use a worked example of data on yellowhammer distribution collected over 4 years to highlight the pitfalls of stepwise regression. We show that stepwise regression allows models containing significant predictors to be obtained from each year's data. In spite of the significance of the selected models, they vary substantially between years and suggest patterns that are at odds with those determined by analysing the full, 4-year data set. 4. An information theoretic (IT) analysis of the yellowhammer data set illustrates why the varying outcomes of stepwise analyses arise. In particular, the IT approach identifies large numbers of competing models that could describe the data equally well, showing that no one model should be relied upon for inference. [ABSTRACT FROM AUTHOR]

Forest bats of eastern North America select habitats for roosting, foraging, and winter hibernation/migration over a myriad of scales. An understanding of forest-bat habitat use over scales of time and space is important for their conservation and management. The papers in this Special Section report studies of bat habitat use across multiple scales from locations across the eastern forests of North America. The consensus of the studies in the Special Section is that the larger portion of the variability in bat habitat use occurs at the smaller scales of sites (roost trees) and stands (foraging areas). Nevertheless, it was also recognized that these features occur discontinuously across larger-scale watersheds and landscapes. [ABSTRACT FROM AUTHOR]

Keywords: accelerometer; animal movement; behaviour; biologging; GPS; modelling; sensor technology; tracking Technological solutions to record the movements, behaviour and physiology of animals, and associated methodological advancements for analysing the data collected, have revolutionized research in animal ecology and beyond (Brisson-Curadeau, Patterson, Whelan, Lazarus, & Elliott, [18]; Kenward, [56]; Ropert-Coudert, Beaulieu, Hanuise, & Kato, [91]; Ropert-Coudert & Wilson, [92]; Weimerskirch, [107]). The general term for this technological approach to study animals is called Biologging - 'the use of miniaturized animal-attached tags for logging and/or relaying data about an animal's movements, behaviour, physiology, and/or environment' (Rutz & Hays, [94]). Thanks to ever smaller loggers which can record an animal's behaviour for ever longer periods of time, biologging is now allowing researchers to study with unprecedented detail how behaviours develop in slow-maturing animals. While an increasing body of research has shown the impact of consistent individual differences in behavioural phenotypes, called animal personalities or behavioural syndromes (Réale et al., [89]; Sih, Bell, Johnson, & Ziemba, [96]), on foraging behaviour, exploratory movements and other spatial behaviours (Bijleveld et al., [12]; Boon, Réale, & Boutin, [15]; Minderman et al., [75]; van Overveld & Matthysen, [103]; Villegas-Ríos, Réale, Freitas, Moland, & Olsen, [105]; Wilson & McLaughlin, [112]), the important relationship between animal personality and foraging site fidelity has not been studied yet. [Extracted from the article]

During the last decade, there has been a proliferation of statistical methods for studying resource selection by animals. While statistical techniques are advancing at a fast pace, there is confusion in the conceptual understanding of the meaning of various quantities that these statistical techniques provide., Terms such as selection, choice, use, occupancy and preference often are employed as if they are synonymous. Many practitioners are unclear about the distinctions between different concepts such as 'probability of selection,' 'probability of use,' 'choice probabilities' and 'probability of occupancy'., Similarly, practitioners are not always clear about the differences between and relevance of 'relative probability of selection' vs. 'probability of selection' to effective management., Practitioners also are unaware that they are using only a single statistical model for modelling resource selection, namely the exponential probability of selection, when other models might be more appropriate. Currently, such multimodel inference is lacking in the resource selection literature., In this paper, we attempt to clarify the concepts and terminology used in animal resource studies by illustrating the relationships among these various concepts and providing their statistical underpinnings. [ABSTRACT FROM AUTHOR]

The article compares methods for predictive modelling of species geographical distributions and the modelling of habitat selection by animals. It states that the modelling of species geographical distribution and habitat selection are based on the environmental conditions and also analyses the selection of resources by animals. It discusses utilization distributions (UDs) and utilization functions (RUF) that play an important role in the modelling of habitat selection.

This paper reports the very first data on the denning habits of the little-studied Molina's hog-nosed skunk ( Conepatus chinga). We identified and characterized 240 (males: n = 92, females: n = 148) den sites used by nine radio-tracked skunks from November 2002 to October 2003 and from December 2005 to October 2007. Most dens were found in underground burrows and we found no variation in dimensions of den entrances across seasons. On average, 24.1% of the den sites were reused by C. chinga. Den sites were not homogeneously distributed within an animal's home range, being the density in core areas greater than in proximity to the borders of home ranges. C. chinga selected specific habitat characteristics for their den sites, such as high shrub and grass cover. Accordingly, the habitats preferred by skunks were native grasslands and pastures. Also, C. chinga preferred den sites located close to fences, roads, and grass patches. We argue that these preferences for den sites may provide two, not mutually exclusive, advantages: access to consistent and predictable sources of food, and protection from predators. Our results suggest that availability of semi-natural grassland and pasture areas may favor the conservation of C. chinga in the human-modified landscapes of the Pampas. [ABSTRACT FROM AUTHOR]

This paper outlines population trends (with confidence intervals) for 49 species in woodland habitats in Britain as monitored by the British Trust for Ornithology’s (BTO) Common Bird Census (CBC) between 1967 and 1999. Additionally, the possible causes of these population trends are investigated by relating the ecological characteristics of species to the degree of population change they have undergone over different time periods. Over the whole period, 17 species showed significant decreases in abundance and 12 species showed significant increases. Whilst population trajectories were diverse, long-distance migrants showed more negative trends than other species and the timing of the changes in their populations was related to their wintering latitude, suggesting that these species may be suffering from environmental changes in the non-breeding season. There was also support for habitat specializations being related to population changes, with species classified as scrub and understorey specialists declining on average, but this was only evident across the entire study period. Additionally, species eating seeds in summer declined and those eating vegetation and making use of the agricultural landscape matrix increased. Therefore wide-scale factors such as landscape-scale processes or processes operating outside of Britain appear to be important in addition to local habitat change, especially for long-distance migrants. [ABSTRACT FROM AUTHOR]

A conference paper about the habitat selection in relation to foraging activities of 48 female Australian fur seals is presented. It discusses the popular breeding sites of the said mammals, which is identified to be located in northern Bass Strait through satellite telemetry. It presents an analysis of habitat use as well as temporal analysis of at-sea movements.

Resource-selection probability functions and occupancy models are powerful methods of identifying areas within a landscape that are highly used by a species. One common design/analysis method for estimation of a resource-selection probability function is to classify a sample of units as used or unused and estimate the probability of use as a function of independent variables using, for example, logistic regression. This method requires that resource units are correctly classified as unused (i.e., the species is never undetected in a used unit), or that the probability of misclassification is the same for all units. In this paper, I explore these issues, illustrating how misclassifying units as unused may lead to incorrect conclusions about resource use. I also show how recently developed occupancy models can be utilized within the resource-selection context to improve conclusions by explicitly accounting for detection probability. These models require that multiple surveys be conducted at each of a sample of resource units within a relatively short timeframe, but given the growing evidence from simulation studies and field data, I recommend that such procedures should be incorporated into studies of resource use. [ABSTRACT FROM AUTHOR]

Despite many decades of study, scientists cannot answer why colonial breeding has evolved. This paper shows that the evolution of colonial breeding cannot be sufficiently explained by the evolutionary conditions proposed in previous studies. Until now, studies have compared colonial breeding with only solitary non-territorial breeding (two-state comparison) and have discussed factors that facilitate evolution of the former. Here, I propose a new approach, a three-state comparison, which compares colonial breeding with not only solitary non-territorial breeding but also solitary territorial breeding. This three-state comparison indicates that (i) merely determining the factors that make colonial breeding advantageous over non-territorial solitary breeding is not sufficient to explain the evolution of colonial breeding, (ii) the disadvantages of solitary territorial breeding can promote the evolution of colonial breeding, and (iii) the evolution of colonial breeding is far more influenced by different selection pressures than has been predicted by previous studies. Thus, the three-state comparison provides a more precise description of the conditions that lead to the evolution of colonial breeding. [ABSTRACT FROM AUTHOR]

Interspecific competition is one of several constraints that might prevent an individual from maximising its energy intake. When an interspecific competitor is introduced, an individual is often forced to shift its diet according to the intensity of the competitive pressure. In this paper, we explore whether the introduced American mink ( Mustela vison Schreber) shifts its diet when the density of its potential competitor, the Eurasian otter ( Lutra lutra L.), is increased. We compared the diets of otter and mink at the same location but at two moments in time when the relative densities of these two species were different while controlling for the abundance of aquatic prey. Mink and otters are semi-aquatic mammals belonging to the same guild of mustelids and otters are expected to be the dominant competitor because they are larger and better at hunting underwater. The diets of otters and mink overlap to a great extent but while otters specialise mainly on aquatic prey, mink are able to exploit both aquatic and terrestrial prey. These observations prompted the hypothesis investigated in this work that at higher otter densities the diet of mink should change to include a higher proportion of terrestrial items. This hypothesis was supported by the data and at higher otter densities mink diet was observed to consist of a higher proportion of mammals and birds while fewer fish were present, although this pattern was present only in winter while no changes were observed in spring. Meanwhile the diet of otters remained basically unchanged. In the second part of the study, we investigated whether niche breadth and niche overlap between otter and mink changed at different otter densities. We found that niche overlap declined as the density of otters increased, in agreement with the prediction of habitat selection theory. [ABSTRACT FROM AUTHOR]

Visibility (viewshed) plays a significant and diverse role in animals' behaviour and fitness. Understanding how visibility influences animal behaviour requires the measurement of habitat visibility at spatial scales commensurate to individual animal choices. However, measuring habitat visibility at a fine spatial scale over a landscape is a challenge, particularly in highly heterogeneous landscapes (e.g. forests). As a result, our ability to model the influence of fine‐scale visibility on animal behaviour has been impeded or limited.In this study, we demonstrate the application of the concept of three‐dimensional (3D) cumulative viewshed in the study of animal spatial behaviour at a landscape level. Specifically, we employed a newly described approach that combines terrestrial and airborne light detection and ranging (LiDAR) to measure fine‐scale habitat visibility (3D cumulative viewshed) on a continuous scale in forested landscapes. We applied the LiDAR‐derived visibility to investigate how visibility in forests affects the summer habitat selection and the movement of 20 GPS‐collared female red deer Cervus elaphus in a temperate forest in Germany. We used integrated step selection analysis to determine whether red deer show any preference for fine‐scale habitat visibility and whether visibility is related to the rate of movement of red deer.We found that red deer selected intermediate habitat visibility. Their preferred level of visibility during the day was substantially lower than that of night and twilight, whereas the preference was not significantly different between night and twilight. In addition, red deer moved faster in high‐visibility areas, possibly mainly to avoid predation and anthropogenic risk. Furthermore, red deer moved most rapidly between locations in the twilight.For the first time, the preference for intermediate habitat visibility and the adaption of movement rate to fine‐scale visibility by a forest‐dwelling ungulate species at a landscape scale was revealed. The LiDAR technique used in this study offers fine‐scale habitat visibility at the landscape level in forest ecosystems, which would be of broader interest in the fields of animal ecology and behaviour. [ABSTRACT FROM AUTHOR]

Translocation and captivity are important tools for conservation biology and wildlife management. Understanding the movement ecology of animals following their release in novel terrain is critical to predicting the success of wildlife restoration efforts. Mountain caribou have high conservation value – efforts to restore their populations across western Canada involve hundreds of millions of dollars in science, monitoring, and management activity. Here, we examined the movements of adult female caribou (N = 36) following their translocation to, and release from, a maternity pen ('penned caribou') and compared these movements to animals that were not translocated ('unpenned caribou', N = 22). A maternity pen is a temporary holding facility, within the animals' existing range, that enables them to bear and raise their young in the absence of predators and with augmented resources. Penned and unpenned animals had similar home range sizes (1052.2 and 1314.6 km2, respectively, P = 0.46) though penned animals moved through the landscape in a faster yet less directed manner. We found some evidence that memory may improve the efficiency of space use. Home ranges with higher quality habitats tended to be smaller than home ranges with poorer quality habitats irrespective of penning status. Penned animals ranged at lower elevation (~150 m) than unpenned animals, particularly in spring and early winter. For penned animals, we did not detect evidence of homing back to the original capture site. The best predictor of how caribou will use the landscape appears to be proximity to the location of the release site. To maximize the fitness of released caribou, future plans for maternity pens and captive breeding programs need to consider the management of food, predators, and habitat across the 1000–2000 km2 that will form the home range near the release site. [ABSTRACT FROM AUTHOR]

The development of methods to analyze habitat selection when resources are defined by several categories (e.g., vegetation types) is a topical issue in radio-tracking studies. The White and Garrott statistic, an extension of the widely used test of Neu et al., can be used to determine whether habitat selection is significant. As well, Manly's selection ratio, a particularly useful measure of resource selectivity by resource users, allows detection of the most strongly selected habitat types. However, when both the number of animals and types of habitat are large, the biologist often has to deal with an excessively large number of measures. In this paper we present a new method, the eigenanalysis of selection ratios, that generalizes these two common methods within the framework of eigenanalyses. This method undertakes an additive linear partitioning of the White and Garrott statistic, so that the difference between habitat use and availability is maximized on the first factorial axes. The eigenanalysis of selection ratios is therefore optimal in habitat selection studies. Although we primarily consider the case where the habitat availability is the same for all animals (design II), we also extend this analysis to the case where the habitat availability varies from one animal to another (design III). An application of this method is provided using radio-tracking data collected on 17 squirrels in five habitat types. The results indicate variability in habitat selection, with two groups of animals displaying two patterns of preference. This difference between the two groups is explained by the patch structure of the study area. Because this method is mainly exploratory, and therefore does not rely on any distributional assumption, we recommend its use in studies of habitat selection. [ABSTRACT FROM AUTHOR]

Understanding habitat selection is of primary interest in theoretical and applied ecology. One approach is to infer habitat selection processes from differences in population densities between habitats using methods such as isodar and isoleg analysis. Another approach is to directly observe the movements of individuals. However, habitat selection models based on movement data often fail to adequately incorporate spatial processes. This is problematic if the probability of selecting a particular habitat is dependent upon its spatial context. This would occur, for example, where organisms exhibit home range behavior and the choice of habitat is dependent on its location relative to the home range. In this paper we present a spatially explicit habitat selection model for movement data that incorporates home range behavior as a spatial process. Our approach extends a previous model by formulating the probability of selecting a habitat as a function of its distance from the animal's current location and home range center. We demonstrate that these enhancements lead to more parsimonious models when applied to a koala radio- tracking data set from eastern Australia. This approach could also be applied to modeling other spatial habitat selection processes, leading to more biologically meaningful models for a range of species and applications. [ABSTRACT FROM AUTHOR]

Many publications make use of opportunistic data, such as citizen science observation data, to infer large‐scale properties of species' distributions. However, the few publications that use opportunistic citizen science data to study animal ecology at a habitat level do so without accounting for spatial biases in opportunistic records or using methods that are difficult to generalize. In this study, we explore the biases that exist in opportunistic observations and suggest an approach to correct for them. We first examined the extent of the biases in opportunistic citizen science observations of three wild ungulate species in Norway by comparing them to data from GPS telemetry. We then quantified the extent of the biases by specifying a model of the biases. From the bias model, we sampled available locations within the species' home range. Along with opportunistic observations, we used the corrected availability locations to estimate a resource selection function (RSF). We tested this method with simulations and empirical datasets for the three species. We compared the results of our correction method to RSFs obtained using opportunistic observations without correction and to RSFs using GPS‐telemetry data. Finally, we compared habitat suitability maps obtained using each of these models. Opportunistic observations are more affected by human access and visibility than locations derived from GPS telemetry. This has consequences for drawing inferences about species' ecology. Models naïvely using opportunistic observations in habitat‐use studies can result in spurious inferences. However, sampling availability locations based on the spatial biases in opportunistic data improves the estimation of the species' RSFs and predicted habitat suitability maps in some cases. This study highlights the challenges and opportunities of using opportunistic observations in habitat‐use studies. While our method is not foolproof it is a first step toward unlocking the potential of opportunistic citizen science data for habitat‐use studies. [ABSTRACT FROM AUTHOR]

Spatially heterogeneous landscapes provide solutions to the forage‐safety trade‐off when animals can access risky but energetically rewarding patches, or safer but resource‐poor patches. It can be advantageous for an animal to secure access to habitat heterogeneity at a broader scale in order to be able to dynamically adjust finer scale habitat use through time. We tested the hypothesis of a forage‐safety trade‐off optimization tactic in a hunted red deer (Cervus elaphus) population following a large accidental forest fire. We used telemetry data and fitted resource selection functions at the second‐ and third‐order scales. We then integrated the order‐specific probabilities into single, all‐in‐one multi‐level layers that synthetically captured the habitat selection patterns across scales by informing landscape‐scale annual habitat selectivity with finer within‐home‐range seasonal and diel processes. At the landscape scale, red deer anchored their home‐range at the interface of the disturbed and undisturbed patches, thereby securing habitat heterogeneity. This consequently enabled them to modulate within‐home‐range habitat selection depending on the season and the time of the day. In both seasons, red deer consistently used the burnt area for cover more during the day, and foraged in the unburnt forest and open fields at night. Interestingly there were no major seasonal differences in this diel habitat selection patterns. Increased mortality risk during the hunting season did not substantially change their spatial behaviour. We conclude that year‐round avoidance of non‐lethal human disturbance is the main driver of red deer habitat use in this system. [ABSTRACT FROM AUTHOR]

Recent work on habitat selection has shown that the perceived quality of habitat patches may depend on the quality of adjacent patches. However, it is still unclear how local habitat selection cues can alter distribution patterns in metacommunities at a larger (regional) scale. We studied mosquito oviposition in pond landscapes that differed in the proportion of bad patches with fish predation risk. Our experiment provided conclusive evidence for two local and two regional types of habitat selection. Good patches near bad patches were avoided (local risk contagion) while more distant good patches experienced increased oviposition (regional compression). Oviposition in bad patches increased when located next to good patches (reward contagion) or when there were no good patches regionally present (regional compromise). This complex colonisation behaviour involving compromises at different spatial scales forces experimenters to reconsider the independence of spatial replicates and challenges available theories to predict species distribution patterns. [ABSTRACT FROM AUTHOR]

1. Determining which environmental traits enable animals to inhabit and choose preferred habitats is key to understanding ecological processes. Habitat complexity and background colour patterns can act as selective pressures on animal behaviour, and ultimately affect habitat choice. 2. To investigate the role of environmental features on habitat selection, this study looked at whether dragonfly and damselfly larvae show a preference between dark/light or complex environments. Last‐instar larvae of Micrathyria didyma (Odonata: Libellulidae) and Acanthagrion lancea (Odonata: Coenagrionidae) were collected in the Neotropical savanna, and five experiments in laboratory conditions were subsequently carried out. The first experiment tested the preference of larvae for leaves in contrast to a white background. The second experiment compared a preference for white and black backgrounds. As both experiments showed a significant preference for darker backgrounds, a predator was included in the black background in the third experiment, and a macrophyte was included in the white background in the fourth experiment. In this way, favourable and unfavourable conditions were included in the habitat of choice. The fifth experiment tested the influence of environmental complexity on habitat choice. 3. The results of these experiments showed that larvae choose darker backgrounds independently of predation risk, and that macrophytes are as attractive as a dark background. They also suggest that the coenagrionid, but not the libellulid, prefer more complex environments. 4. Overall, these findings suggest that larvae exhibit behavioural preferences for background colour and complexity, which may ultimately drive habitat occupation. [ABSTRACT FROM AUTHOR]

Behaviour is the interface between an organism and its environment, and behavioural plasticity is important for organisms to cope with environmental change. Social behaviour is particularly important because sociality is a dynamic process, where environmental variation influences group dynamics and social plasticity can mediate resource acquisition. Heterogeneity in the ecological environment can therefore influence the social environment. The combination of the ecological and social environments may be interpreted collectively as the 'socioecological environment,' which could explain variation in fitness., Our objective was to outline a framework through which individual social and spatial phenotypes can be integrated and interpreted as phenotypes that covary as a function of changes in the socioecological environment. We propose the socioecological environment is composed of individual behavioural traits, including sociality and habitat selection, both of which are repeatable, potentially heritable and may reflect animal personality traits. We also highlight how ecological and social niche theory can be applied to the socioecological environment framework, where individuals occupy different socioecological niches. Individual sociality and habitat selection are also density-dependent, and theory predicts that density-dependent traits should affect reproduction, survival, and therefore fitness and population dynamics., We then illustrate the proximate links between sociality, habitat selection and fitness as well as the ultimate, and possibly adaptive, consequences associated with changes in population density. The ecological, evolutionary and applied implications of our proposed socioecological environment framework are broad and changes in density could influence individual fitness and population dynamics. For instance, human-induced environmental changes can influence population density, which can affect the distribution of social and spatial phenotypes within a population. In summary, we outline a conceptual framework that incorporates individual social and spatial behavioural traits with fitness and we highlight a range of ecological and evolutionary processes that are likely associated with the socioecological environment. [ABSTRACT FROM AUTHOR]

Interspecific social information transfer can play a key role in many aspects of animal ecology from foraging to habitat selection to predator avoidance., Within scavenging communities, avian scavengers often act as producers and mammalian scavengers act as scroungers, but we predict that species-specific cueing will allow for mammalian scavengers to utilize particular avian scavenger species using preferred food sources similar to their own preferences., We use empirical and theoretic approaches to assess interactions between mammalian and avian scavengers in one of the most diverse scavenging guilds in Masai Mara National Reserve, Kenya., Using a spatially explicit model and data from experimental carcasses, we found evidence that mammals benefit from local enhancement provided by vultures and that mammalian-avian following patterns are consistent with the idea that species-specific cueing is occurring., Results suggest that ongoing population declines in avian scavengers may have significant impacts on mammalian scavengers and potentially create trophic cascades. [ABSTRACT FROM AUTHOR]

Predator avoidance depends on prey being able to discern how risk varies in space and time, but this is made considerably more complicated if risk is simultaneously present from multiple predators. This is the situation for an increasing number of mammalian prey species, as large carnivores recover or are reintroduced in ecosystems on several continents. Roe deer Capreolus capreolus in southern Norway illustrate a case in which prey face two predators with contrasting patterns of predation risk. They face a catch-22 situation: spatially avoiding the risk from one predator (lynx Lynx lynx in dense habitat) implies exposure to the other (hunters in open habitat). Using GPS-data from 29 roe deer, we tested for daily and seasonal variation in roe deer selection for habitat with respect to the habitats' year-round average risk level. Generally, roe deer altered their habitat selection between night and day in a pattern consistent with being able to avoid predicted risk from the nocturnal lynx during night and predicted risk from human hunters during day. However, seasonal variation in habitat selection only partially corresponded with the predicted seasonal variation in risk. Whereas roe deer avoided areas with high risk from hunters more strongly during the hunting season than in other seasons, there was a lack of selection towards areas and time periods lowering the risk of lynx predation during winter. It seems likely that the risk of starvation and thermal stress constrain roe deer habitat selection during this energetically challenging season with cold temperatures, snow cover and limited natural forage. The habitat selection pattern of roe deer fits thus only partly with the two contrasting risk gradients they face. Adjusting risk-avoidance behavior temporally can be an adaptive response in the case of several predators whose predation patterns differ in space and time. [ABSTRACT FROM AUTHOR]

Weather is a source of environmental variation that can affect population vital rates. However, the influence of weather on individual fitness is spatially heterogeneous and can be driven by other environmental factors, such as habitat composition. Therefore, individuals can experience reduced fitness (e.g., decreased reproductive success) during poor environmental conditions through poor decisions regarding habitat selection. This requires, however, that habitat selection is adaptive and that the organism can correctly interpret the environmental cues to modify habitat use. Greater Sage-Grouse ( Centrocercus urophasianus) are an obligate of the sagebrush ecosystems of western North America, relying on sagebrush for food and cover. Greater Sage-Grouse chicks, however, require foods with high nutrient content (i.e., forbs and insects), the abundance of which is both temporally and spatially dynamic and related primarily to water availability. Our goal was to assess whether nest site selection and movements of broods by females reduced the negative effect of drought on offspring survival. As predicted, chick survival was negatively influenced by drought severity. We found that sage-grouse females generally preferred to nest and raise their young in locations where their chicks would experience higher survival. We also found that use of habitats positively associated with chick survival were also positively associated with drought severity, which suggests that females reduced drought impacts on their dependent young by selecting more favorable environments during drought years. Although our findings suggest that female nest site selection and brood movement rates can reduce the negative effects of drought on early offspring survival, the influence of severe drought conditions was not completely mitigated by female behavior, and that drought conditions should be considered a threat to Greater Sage-Grouse population persistence. [ABSTRACT FROM AUTHOR]

Polygynous species follow sex-specific spacing patterns to maximize reproductive success, and changes in population density under otherwise stable environmental conditions likely provoke sex-specific responses in spacing patterns. A classical dual reproductive strategy hypothesis posits that female home range size and overlap are set by habitat productivity and remain stable under increasing population density, whereas male home range size and overlap decrease with increased mate competition. An alternative dispersal-regulated strategy predicts that females relinquish part of their home range to philopatric daughters and form matrilineal clusters, while adult male spacing is stable with density-dependent subadult male emigration rates. We used 11 years of telemetry data to assess the response of adult leopard Panthera pardus spacing following the release of harvest pressure. Female annual home ranges and core areas were smaller than in males. Intersexual overlap was larger than intra-sexual overlap in males or in females. As leopard density increased, female home range size and inter-annual fidelity in home range use decreased, and females formed matrilineal kin clusters. In contrast, male leopards maintained large home ranges, and did not track female home range contraction. Spacing dynamics in adult leopards was consistent with dispersal-regulated strategies, and did not support a classical dual reproductive strategy. Our study suggests possible hidden lag effects of harvest disturbance on spacing dynamics that are not necessarily apparent when only assessing demographic recovery of harvested populations. [ABSTRACT FROM AUTHOR]

ABSTRACT Wildlife home ranges continue to be a common spatial unit for modeling animal habitat selection. Telemetry data are increasing in spatial and temporal detail and new methods are being developed to incorporate fine resolution data into home range delineation. We extended a previously developed home range estimation technique that incorporates theory from time geography, the potential path area (PPA) home range, to allow the home range to be defined at multiple spatial scales depending on the observed rate of movement within the data. The benefits of this approach are demonstrated with a simulation study, which uses multi-state correlated random walks to represent dynamic movement phases to compare the modified PPA home range technique with a suite of other home range estimation methods (PPA home range, kernel density estimation, Brownian bridges, and dynamic Brownian bridges). We used a case study on caribou ( Rangifer tarandus) movement from northern Canada to highlight the value of this approach for characterizing habitat conditions associated with wildlife habitat analysis. We used a simple habitat covariate, percent forest cover, to explore the potential for misleading habitat estimates when home ranges do not include potentially visited locations (omission area) or include areas not possibly visited (commission area). We highlight the advantages of the dynamic PPA home range in the context of quantifying omission and commission areas in other home range techniques. Finally, we provide our R code for calculating dynamic PPA home range estimates. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

An extensive body of theory suggests that density-dependent habitat selection drives many fundamental ecological processes. The ideal free distribution and the ideal despotic distribution make contrasting predictions about the effect of total population size on relative abundances among habitats. Empirical assessment of these habitat selection models is uncommon because data must be collected over large temporal and spatial scales., I ask whether fluctuation in Chinook salmon ( Oncorhynchus tshawytscha) spawner population size through time leads to different relative densities over space., Twenty-six years of monitoring data on spawning Chinook salmon across the entire coast of Oregon, USA, were used to evaluate models that make contrasting statements about the interactions of a latent population abundance parameter with physical habitat characteristics., There is strong information-theoretic support for models that include terms that allow the spatial variation in density to change as population size changes through time. Analysis of the best model reveals nonlinear isodars, which suggests a 'despotic' or 'preemptive' distribution of individuals across habitats, indicating that dominant or early-arriving individuals exclude others from breeding sites., This finding has implications for genetic dynamics, population dynamics and conservation metrics of these highly valued fish. The novel application of modelling techniques used here to assess mechanisms of habitat selection from observational data can be used in the emerging field of eco-evolutionary dynamics. [ABSTRACT FROM AUTHOR]

Analyses based on utilization distributions (UDs) have been ubiquitous in animal space use studies, largely because they are computationally straightforward and relatively easy to employ. Conventional applications of resource utilization functions (RUFs) suggest that estimates of UDs can be used as response variables in a regression involving spatial covariates of interest., It has been claimed that contemporary implementations of RUFs can yield inference about resource selection, although to our knowledge, an explicit connection has not been described., We explore the relationships between RUFs and resource selection functions from a hueristic and simulation perspective. We investigate several sources of potential bias in the estimation of resource selection coefficients using RUFs (e.g. the spatial covariance modelling that is often used in RUF analyses)., Our findings illustrate that RUFs can, in fact, serve as approximations to RSFs and are capable of providing inference about resource selection, but only with some modification and under specific circumstances., Using real telemetry data as an example, we provide guidance on which methods for estimating resource selection may be more appropriate and in which situations. In general, if telemetry data are assumed to arise as a point process, then RSF methods may be preferable to RUFs; however, modified RUFs may provide less biased parameter estimates when the data are subject to location error. [ABSTRACT FROM AUTHOR]

If animals moved randomly in space, the use of different habitats would be proportional to their availability. Hence, deviations from proportionality between use and availability are considered the tell-tale sign of preference. This principle forms the basis for most habitat selection and species distribution models fitted to use-availability or count data (e.g. MaxEnt and Resource Selection Functions)., Yet, once an essential habitat type is sufficiently abundant to meet an individual's needs, increased availability of this habitat type may lead to a decrease in the use/availability ratio. Accordingly, habitat selection functions may estimate negative coefficients when habitats are superabundant, incorrectly suggesting an apparent avoidance. Furthermore, not accounting for the effects of availability on habitat use may lead to poor predictions, particularly when applied to habitats that differ considerably from those for which data have been collected., Using simulations, we show that habitat use varies non-linearly with habitat availability, even when individuals follow simple movement rules to acquire food and avoid risk. The results show that the impact of availability strongly depends on the type of habitat (e.g. whether it is essential or substitutable) and how it interacts with the distribution and availability of other habitats., We demonstrate the utility of a variety of existing and new methods that enable the influence of habitat availability to be explicitly estimated. Models that allow for non-linear effects (using b-spline smoothers) and interactions between environmental covariates defining habitats and measures of their availability were best able to capture simulated patterns of habitat use across a range of environments., An appealing aspect of some of the methods we discuss is that the relative influence of availability is not defined a priori, but directly estimated by the model. This feature is likely to improve model prediction, hint at the mechanism of habitat selection, and may signpost habitats that are critical for the organism's fitness. [ABSTRACT FROM AUTHOR]

Analyses of animal resource selection functions ( RSF) using data collected from relocations of individuals via remote telemetry devices have become commonplace. Increasing technological advances, however, have produced statistical challenges in analysing such highly autocorrelated data. Weighted distribution methods have been proposed for analysing RSFs with telemetry data. However, they can be computationally challenging due to an intractable normalizing constant and cannot be aggregated (i.e. collapsed) over time to make space-only inference., In this study, we take a conceptually different approach to modelling animal telemetry data for making RSF inference. We consider the telemetry data to be a realization of a space-time point process. Under the point process paradigm, the times of the relocations are also considered to be random rather than fixed., We show the point process models we propose are a generalization of the weighted distribution telemetry models. By generalizing the weighted model, we can access several numerical techniques for evaluating point process likelihoods that make use of common statistical software. Thus, the analysis methods can be readily implemented by animal ecologists., In addition to ease of computation, the point process models can be aggregated over time by marginalizing over the temporal component of the model. This allows a full range of models to be constructed for RSF analysis at the individual movement level up to the study area level., To demonstrate the analysis of telemetry data with the point process approach, we analysed a data set of telemetry locations from northern fur seals ( Callorhinus ursinus) in the Pribilof Islands, Alaska. Both a space-time and an aggregated space-only model were fitted. At the individual level, the space-time analysis showed little selection relative to the habitat covariates. However, at the study area level, the space-only model showed strong selection relative to the covariates. [ABSTRACT FROM AUTHOR]

Habitat selection is a fundamental aspect of animal ecology, the understanding of which is critical to management and conservation. Global positioning system data from animals allow fine-scale assessments of habitat selection and typically are analyzed in a use-availability framework, whereby animal locations are contrasted with random locations (the availability sample). Although most use-availability methods are in fact spatial point process models, they often are fit using logistic regression. This framework offers numerous methodological challenges, for which the literature provides little guidance. Specifically, the size and spatial extent of the availability sample influences coefficient estimates potentially causing interpretational bias. We examined the influence of availability on statistical inference through simulations and analysis of serially correlated mule deer GPS data. Bias in estimates arose from incorrectly assessing and sampling the spatial extent of availability. Spatial autocorrelation in covariates, which is common for landscape characteristics, exacerbated the error in availability sampling leading to increased bias. These results have strong implications for habitat selection analyses using GPS data, which are increasingly prevalent in the literature. We recommend that researchers assess the sensitivity of their results to their availability sample and, where bias is likely, take care with interpretations and use cross validation to assess robustness. [ABSTRACT FROM AUTHOR]

Autecologic information of aquatic insects in the river systems under extreme continental climatic conditions is limited. Therefore, the objective of this study was to analyze life cycles, larval development, densities, microhabitat distribution, and secondary production of two sympatric burrowing mayfly species, Ephemera orientalis and Ephoron nigridorsum, in the Kharaa River, Northern Mongolia. Both species were typically distributed within the middle reaches of the focus river, displaying significant different larval densities across the three study sites. Four distinct microhabitats for E. orientalis and E. nigridorsum were identified. The preferred habitats of both species were substrates composed of rocks, cobbles, or coarse gravels with variable smaller mineral fractions of finer sandy, muddy, or organic substrates beside. Based on larval body size distribution and the emergence period, it was concluded that E. orientalis has a univoltine winter life cycle. The estimated annual production of larvae at two investigated sites in the middle stretch of the river in the year 2009 was 1.65 and 2.25 g DW m−2 year−1. Biomass was 294.8 and 490.3 mg DW m−2, and the annual production to biomass rate (P/B) was 4.5 and 5.6 year−1, respectively. In contrast, E. nigridorsum displayed a univoltine summer life cycle with a very likely egg diapause of approximately 8 months. Annual production estimates were 5.27 and 7.89 g DW m−2 year−1, biomass was 281.2 and 443.2 mg DW m−2; the annual P/B rates were 17.9 and 18.7 year−1 at the two sites reflecting the extremely shortened life cycle of this species. We conclude that the two sympatric species showed a difference in life cycles but no separation in habitat selection. [ABSTRACT FROM AUTHOR]

Resource selection function (RSF) models are commonly used to quantify species/habitat associations and predict species occurrence on the landscape. However, these models are sensitive to changes in resource availability and can result in a functional response to resource abundance, where preferences change as a function of availability. For generalist species, which utilize a wide range of habitats and resources, quantifying habitat selection is particularly challenging. Spatial and temporal changes in resource abundance can result in changes in selection preference affecting the robustness of habitat selection models. We examined selection preference across a wide range of ecological conditions for a generalist mega-herbivore, the African savanna elephant Loxodonta africana, to quantify general patterns in selection and to illustrate the importance of functional responses in elephant habitat selection. We found a functional response in habitat selection across both space and time for tree cover, with tree cover being unimportant to habitat selection in the mesic, eastern populations during the wet season. A temporal functional response for water was also evident, with greater variability in selection during the wet season. Selection for low slopes, high tree cover, and far distance from people was consistent across populations; however, variability in selection coefficients changed as a function of the abundance of a given resource within the home range. This variability of selection coefficients could be used to improve confidence estimations for inferences drawn from habitat selection models. Quantifying functional responses in habitat selection is one way to better predict how wildlife will respond to an ever-changing environment, and they provide promising insights into the habitat selection of generalist species. [ABSTRACT FROM AUTHOR]

The two marsupial moles are the sole extant members of the order Notoryctemorphia, an ancient Australian lineage, with extreme adaptations for fossoriality. We tested whether the order conforms to the expectation that the low productivity of subterranean environments results in subterranean mammals being generalist feeders. To do this, we examined diet, invertebrate availability in foraging areas and prey selection by the southern marsupial mole or Itjaritjari Notoryctes typhlops, which occupies the sand deserts of southern and central Australia. Because the species is so infrequently encountered, we examined digestive tracts from museum specimens which themselves are rare; we obtained access to ∼12% of all specimens available in Australia's museums. Our invertebrate sampling protocol was based on a novel survey method, which, for the first time, enables quantification of the distribution and habitat use of N. typhlops. We sampled topographic positions on sandridges and areas of the soil profile (0-70 cm) where marsupial moles forage. Rarefaction methods indicated our sample size was sufficient to record the majority of prey items. Material in digestive tracts of 16 specimens consisted of five insect orders ( Coleoptera, Hymenoptera, Isoptera, Lepidoptera and Orthoptera), scorpions, spiders and plant material. N. typhlops consumed two main prey types: social insects (ants and termites) and the larvae of beetles. Ants, termites and beetle larvae were also the main invertebrates captured in soil cores on sandridges; other invertebrates combined contributed <5% to abundance. Prey selection assessment using Jacobs' index and Bonferroni confidence intervals indicated an active avoidance of termites ( D = −0.61), whereas ants ( D = −0.13) and beetle larvae ( D = 0.57) and all other prey categories were taken in proportion to availability. Our results show that N. typhlops is best classed as a dietary generalist despite its specialized adaptations for a subterranean lifestyle. [ABSTRACT FROM AUTHOR]

Resource partitioning among the ungulate species occupying African savanna ecosystems has been well documented in relation to food resources and habitat features, but few studies have addressed how distinctions in surface water dependency contribute to coexistence. During the dry season surface water becomes restricted to a few perennial sources, while the food resources remaining at this time are also most limited in quantity, especially near water where animals congregate to drink. We compared the movement patterns to and from water of sable antelope Hippotragus niger and zebra Equus quagga herds in Kruger National Park (KNP), South Africa. Owing to distinctions in their digestive systems, we expected sable to drink less frequently than zebra, allowing sable to occupy regions further from surface water than zebra. Sable travelled to water at 2-4-day intervals, versus 1-2-day intervals for zebra. However, sable travelled c. 25% greater distances to water due to the location of their late dry season home ranges relative to perennial water sources; zebra home ranges were generally closer to water sources. Travelling 10-15 km to and from water substantially reduced time spent foraging and resting by both species on days when animals drank. Longer intervals between travel to water by the sable antelope herd enabled it to occupy regions of the landscape further from water than those heavily exploited by the more common grazers during the critical dry season months. By avoiding concentrations of other grazers, the sable also probably gained a reduction in predation risk, balancing the substantial costs in terms of time and energy associated with travel to water. Thereby the distinctions in water dependency of this relatively rare grazer facilitated its coexistence alongside more abundant grazers in the KNP. [ABSTRACT FROM AUTHOR]

Contrary to assumptions of habitat selection theory, field studies frequently detect ' ecological traps ' , where animals prefer habitats conferring lower fitness than available alternatives. Evidence for traps includes cases where birds prefer breeding habitats associated with relatively high nest predation rates despite the importance of nest survival to avian fitness. Because birds select breeding habitat at multiple spatial scales, the processes underlying traps for birds are likely scale-dependent. We studied a potential ecological trap for a population of yellow warblers Dendroica petechia while paying specific attention to spatial scale. We quantified nest microhabitat preference by comparing nest-versus random-site microhabitat structure and related preferred microhabitat features with nest survival. Over a nine-year study period and three study sites, we found a consistently negative relationship between preferred microhabitat patches and nest survival rates. Data from experimental nests described a similar relationship, corroborating the apparent positive relationship between preferred microhabitat and nest predation. As do other songbirds, yellow warblers select breeding habitat in at least two steps at two spatial scales; (1) they select territories at a coarser spatial scale and (2) nest microhabitats at a finer scale from within individual territories. By comparing nest versus random sites within territories, we showed that maladaptive nest microhabitat preferences arose during within-territory nest site selection (step 2). Furthermore, nest predation rates varied at a fine enough scale to provide individual yellow warblers with lower-predation alternatives to preferred microhabitats. Given these results, tradeoffs between nest survival and other fitness components are unlikely since fitness components other than nest survival are probably more relevant to territory-scale habitat selection. Instead, exchanges of individuals among populations facing different predation regimes, the recent proliferation of the parasitic brown-headed cowbird Molothrus ater , and/or anthropogenic changes to riparian vegetation structure are more likely explanations. [ABSTRACT FROM AUTHOR]

Effective conservation plans and design of Special Protection Areas (SPAs) for protected species should take into account ranging behaviour and foraging habitats, and this is particularly important for wide-ranging species. Montagu's harriers Circus pygargus are ground-nesting semi-colonial raptors typical of agricultural habitats. We studied the foraging behaviour of 14 radio-tracked male Montagu's harriers, in order to investigate the distance from nests of foraging birds, the extent to which foraging range overlapped with SPAs designated for this species, and foraging habitat selection within foraging ranges. Average foraging range size, estimated from either minimum convex polygon or kernel 90%, was larger than 100 km2. Only 19 ± 11% of the foraging ranges were within SPA limits. Cereal (the main habitat used for nesting) was slightly counterselected for foraging, and most prey (64%, n=117) captured in that habitat were insects. Hunting attempts occurred significantly more frequently than expected in alfalfa, where most prey captured were small mammals (70%, n=102). Use of this habitat for foraging increased throughout the season. Most prey captured in other habitats (mainly tree crops, shrubs or uncultivated land) were birds (83%, n=43). SPAs included a higher proportion of cereal, but a lower proportion of alfalfa than areas outside SPAs. Overall, our results show that breeding Montagu's harriers use an area for foraging much larger than current sizes of most SPAs for the species, that habitats selected for foraging differ from those used for nesting and that preferred foraging habitats were less common inside SPAs than outside. Conservation management for this species should aim to protect foraging habitats within a large radius of the colonies, probably requiring measures to be applied outside protected areas. More generally, SPAs designed without including information of ranging behaviour and foraging habitats may be ineffective. [ABSTRACT FROM AUTHOR]

Understanding and predicting the distribution of organisms in heterogeneous environments lies at the heart of ecology. The spatial distribution of fish populations observed in the wild results from the complex interactions of multiple controls both external or internal to the fish populations. Whilst species distribution models (SDMs) have been mostly concerned with static description of species distribution as a function of environmental constraints, models of animal movements (MAMs) have focussed on the dynamic nature of spatial distribution of groups of individuals under a number of constraints external and internal to the population. Besides SDMs and MAMs, modelling the spatial distribution of fish populations can be achieved by models that are fundamentally static (like SDMs) but can also incorporate many hypotheses on the control of fish spatial distribution (like MAMs). The hypotheses underlying these models need to make sense at the population level - rather than at the individual or species level -we term these 'population distribution models' (PDMs). PDMs are statistical models that rely on several hypotheses, which include: (i) control through geographical attachment, (ii) environmental conditions, (iii) density-dependent habitat selection, (iv) spatial dependency, (v) population demographic structure, (vi) species interactions and (vii) population memory. We review the basis behind each of these conceptual models and we examine corresponding numerical applications. We argue that the conceptual models are complementary rather than competing, that existing numerical applications are still rarely compared and combined, and that PDMs can offer a statistical framework to achieve this. We recommend that the numerical models associated with different hypotheses be constructed within such a common general framework. This will permit evaluation, comparison and combination of the multiple hypotheses on fish spatial distribution. It will ultimately lead to a more comprehensive understanding of the factors controlling the spatial distribution of fish populations and to more accurate predictions in which model uncertainty is accounted for. [ABSTRACT FROM AUTHOR]

1. Several methods have been developed to assess habitat selection, most of which are based on a comparison between habitat attributes in used vs. unused or random locations, such as the popular resource selection functions (RSFs). Spatial evaluation of residency time has been recently proposed as a promising avenue for studying habitat selection. Residency-time analyses assume a positive relationship between residency time within habitat patches and selection. We demonstrate that RSF and residency-time analyses provide different information about the process of habitat selection. Further, we show how the consideration of switching rate between habitat patches (interpatch movements) together with residency-time analysis can reveal habitat-selection strategies. 2. Spatially explicit, individual-based modelling was used to simulate foragers displaying one of six foraging strategies in a heterogeneous environment. The strategies combined one of three patch-departure rules (fixed-quitting-harvest-rate, fixed-time and fixed-amount strategy), together with one of two interpatch-movement rules (random or biased). Habitat selection of simulated foragers was then assessed using RSF, residency-time and interpatch-movement analyses. 3. Our simulations showed that RSFs and residency times are not always equivalent. When foragers move in a non-random manner and do not increase residency time in richer patches, residency-time analysis can provide misleading assessments of habitat selection. This is because the overall time spent in the various patch types not only depends on residency times, but also on interpatch-movement decisions. 4. We suggest that RSFs provide the outcome of the entire selection process, whereas residency-time and interpatch-movement analyses can be used in combination to reveal the mechanisms behind the selection process. 5. We showed that there is a risk in using residency-time analysis alone to infer habitat selection. Residency-time analyses, however, may enlighten the mechanisms of habitat selection by revealing central components of resource-use strategies. Given that management decisions are often based on resource-selection analyses, the evaluation of resource-use strategies can be key information for the development of efficient habitat-management strategies. Combining RSF, residency-time and interpatch-movement analyses is a simple and efficient way to gain a more comprehensive understanding of habitat selection. [ABSTRACT FROM AUTHOR]

Ayllón D, Almodóvar A, Nicola GG, Elvira B. Ontogenetic and spatial variations in brown trout habitat selection. Ecology of Freshwater Fish 2010: 19: 420–432. © 2010 John Wiley & Sons A/S Habitat quality and quantity determine many biological processes and traits that directly affect the population dynamics of stream fishes. Understanding how habitat selection is adjusted to different ecological conditions is essential to improve predictive modelling of population dynamics. We describe brown trout Salmo trutta summer habitat selection patterns through univariate and multivariate habitat selection functions across defined river reach typologies. We sampled 44 sites and performed a principal component analysis that defined eight reach types differing in both local site and catchment-scale physical features. We observed ontogenetic changes in habitat selection, as trout preferred deeper and slower flowing water as they increased in size. Likewise, selectivity for different types of structural habitat elements changed through ontogeny. Both patterns were consistent across reach types. Moreover, we detected spatial variations in habitat selection patterns within age-classes among different reach types. Our results indicate that brown trout is a habitat generalist and suggest that spatial variations in habitat selection patterns are driven by physical and environmental factors operating at multiple spatial scales. [ABSTRACT FROM AUTHOR]

1. Habitat selection models usually assume that the spatial distributions of animals depend positively on the distributions of resources and negatively on interference. However, the presence of conspecifics at a given location also signals safety and the availability of resources. This may induce followers to select contiguous patches and causes animals to cluster. Resource availability, interference and attraction therefore jointly lead to self-organized patterns in foraging animals. 2. We analyse the distribution of foraging shorebirds at landscape level on the basis of a resource-based model to establish, albeit indirectly, the importance of conspecific attraction and interference. 3. At 23 intertidal sites with a mean area of 170 ha spread out over the Dutch Wadden Sea, the spatial distribution of six abundant shorebird species was determined. The location of individuals and groups was mapped using a simple method based on projective geometry, enabling fast mapping of low-tide foraging shorebird distributions. We analysed the suitability of these 23 sites in terms of food availability and travel distances to high tide roosts. 4. We introduce an interference sensitivity scale which maps interference as a function of inter-individual distance. We thus obtain interference-insensitive species, which are only sensitive to interference at short inter-individual distances (and may thus pack densely) and interference-sensitive species which interfere over greater inter-individual distances (and thus form sparse flocks). 5. We found that interference-insensitive species like red knot ( Calidris canutus) and dunlins ( Calidris alpina) are more clustered than predicted by the spatial distribution of their food resources. This suggests that these species follow each other when selecting foraging patches. In contrast, curlew ( Numenius arquata) and grey plover ( Pluvialis squatarola), known to be sensitive to interference, form sparse flocks. Hence, resource-based models have better predictive power for interference-sensitive species than for interference-insensitive species. 6. It follows from our analysis that monitoring programmes, habitat selection models and statistical analyses should also consider the mechanisms of self-organization. [ABSTRACT FROM AUTHOR]

1. Non-consumptive effects of predators are increasingly recognized as important drivers of community assembly and structure. Specifically, habitat selection responses to top predators during colonization and oviposition can lead to large differences in aquatic community structure, composition and diversity. 2. These differences among communities due to predators may develop as communities assemble, potentially altering the relative quality of predator vs. predator-free habitats through time. If so, community assembly would be expected to modify the subsequent behavioural responses of colonists to habitats containing top predators. Here, we test this hypothesis by manipulating community assembly and the presence of fish in experimental ponds and measuring their independent and combined effects on patterns of colonization by insects and amphibians. 3. Assembly modified habitat selection of dytscid beetles and hylid frogs by decreasing or even reversing avoidance of pools containing blue-spotted sunfish ( Enneacanthus gloriosus). However, not all habitat selection responses to fish depended on assembly history. Hydrophilid beetles and mosquitoes avoided fish while chironomids were attracted to fish pools, regardless of assembly history. 4. Our results show that community assembly causes taxa-dependent feedbacks that can modify avoidance of habitats containing a top predator. Thus, non-consumptive effects of a top predator on community structure change as communities assemble and effects of competitors and other predators combine with the direct effects of top predators to shape colonization. 5. This work reinforces the importance of habitat selection for community assembly in aquatic systems, while illustrating the range of factors that may influence colonization rates and resulting community structure. Directly manipulating communities both during colonization and post-colonization is critical for elucidating how sequential processes interact to shape communities. [ABSTRACT FROM AUTHOR]

Modelling habitat of species necessitates robust identification of relevant environmental variables linked to species distribution. To achieve this, we connect hierarchical patch theory and habitat modelling at multiple scales. We suggest discriminating between ‘circumstancial variables’ and ‘process variables’ on the basis of temporal evolution of the spatial links between species distribution and their environment at different scales. ‘Process variables’ are informative of the ecological processes driving the distribution of organisms at multiple scales. By opposition, ‘circumstantial variable’ provide little insight because their relationship with animal spatial distribution is subject to great variations through time. As a real case study, we investigate the relationships between auk distribution (mainly Uria aalge) and oceanographic landscapes over two scales (i.e. large ∼ 200 km and medium ∼ 50 km) during the wintering season in the Bay of Biscay. Surface salinity, mixed layer depth and chlorophyll a are identified as ‘process variables’ as they are invariably correlated with the spatial distribution of auks, whereas bottom temperature can be viewed as a ‘circumstantial variable’ since the correlation is non-constant through time at large scale. The process variables at large scale are used to model the potential habitat of auks in the Bay of Biscay during the wintering season. At medium scale, only the chlorophyll a is identified as ‘process variable’ and used to model preferential habitat of wintering auks in the Bay of Biscay. The analytical approach proposed here (i.e. multivariate factorial kriging in a temporal context) is an effective framework to model the potential and preferential habitat of a species and can be related to the ecological niche concept and by focusing explicitly on scale dependence, the distinction between the variables that can be used as niche descriptors into species distribution models. Then our method lead to the identification of variables that should be used to define the Grinnellian niche which is defined by environmental conditions on broad scales and the Eltonian niche which focuses on biotic interactions and resource–consumer dynamics that can be measured principally at local scales. [ABSTRACT FROM AUTHOR]

1. We used observational and experimental field studies together with an individual-based simulation model to demonstrate that behaviours of mottled sculpin ( Cottus bairdi) were broadly consistent with the expectations of Giving-Up Density theory and an Ideal Pre-emptive Distribution habitat selection model. 2. Specifically we found that: (i) adult mottled sculpin established territories within patches characterised by significantly higher prey densities and prey renewal rates than patches occupied by juveniles or randomly selected patches; (ii) patches abandoned by adult sculpin possessed significantly lower prey densities than newly occupied patches, although this was not true for juveniles; (iii) the observed giving-up density (GUD) for adult sculpin (i.e. average prey density in patches recently abandoned) increased linearly with increasing fish size up to the average prey density measured in randomly selected patches (i.e. 350 prey items per 0.1 m2) and decreased with increasing sculpin density and (iv) juveniles rapidly shifted their distribution towards the highest quality patches following removal of competitively dominant adult sculpin. 3. These results provide the first evidence of the applicability of GUD theory to a stream-dwelling organism, and they elucidate the underlying factors influencing juvenile and adult sculpin habitat selection and movement behaviours. Furthermore, optimal patch use, ideal pre-emptive habitat selection and juvenile ‘floating’ provide behavioural mechanisms linking environmental heterogeneity in the stream benthos to density-dependent regulation of mottled sculpin populations in this system. [ABSTRACT FROM AUTHOR]

Animal movement and habitat selection behavior are important considerations in ecology, and remain a major issue for successful animal reintroductions. However, simple rules are often used to model movement or focus only on intrinsic environmental cues, neglecting recent insights in behavioral ecology on habitat selection processes. In particular, social information has been proposed as a widespread source of information for habitat evaluation. We investigated the role of explicit breeding habitat selection strategies on the establishment pattern of reintroduced populations and their persistence. We considered local movement at the scale of a single population. We constructed a spatially-implicit demographic model that considered five breeding habitat selection rules: 1) random, 2) intrinsic habitat quality, 3) avoidance of conspecifics, 4) presence of conspecifics and 5) reproductive success of conspecifics. The impact of breeding habitat selection was examined for different release methods under various levels of environmental heterogeneity levels, for both long and short-lived monogamous species. When heterogeneity between intrinsic habitat patch qualities is high, the persistence of reintroduced populations strongly depends on habitat selection strategies. Strategies based on intrinsic quality and conspecific reproductive success lead to a lower reintroduction failure risk than random, conspecific presence or avoidance-based strategies. Conspecific presence or avoidance-based strategies may aggregate individuals in suboptimal habitats. The release of adults seems to be more efficient independent of habitat selection strategy. We emphasize the crucial role of oriented habitat selection behavior and non ideal habitat selection in movement modeling, particularly for reintroduction. [ABSTRACT FROM AUTHOR]

Patterns of resource selection by animals may be influenced by sex, and often change over a 24-h period. We used a dry sclerophyll landscape managed for commercial timber production to investigate the effects of sex and diel period on habitat selection by the swamp wallaby ( Wallabia bicolor). We predicted that selection would be (i) affected by both sex and diel period; and (ii) positively related to lateral cover during the day, but to food resources at night. Non-metric multidimentional scaling indicated that some of the available habitats differed markedly with respect to visibility (an indicator of lateral cover), fern cover, forb cover, wallaby density and a forage quality index, providing the basis for non-random habitat selection. At the landscape scale, wallabies showed strong selection for 5-year-old regenerating sites, selected against 10-year-old regenerating sites and unharvested forest, and avoided recently harvested (3–10 months post-harvest) sites completely. At the scale of individual home ranges, a pooled male and female sample demonstrated selection for unharvested forest over recently harvested sites during both diurnal and nocturnal periods. A separate analysis showed that both sex and diel period influenced the selection of 5- and 10-year-old sites and the surrounding unharvested forest. Using a novel approach, we demonstrated that diurnal habitat selection by both sexes was negatively correlated with visibility, representing stronger selection for areas with more lateral cover. Nocturnal selection by females was positively correlated with values of a forage quality index, but this was not the case for males. We hypothesise that the observed patterns of selection were driven by the need to find food and avoid predators, but were also affected by the different reproductive strategies of males and females. Our results demonstrate the importance of incorporating factors such as sex and diel period into analyses of habitat selection. [ABSTRACT FROM AUTHOR]

The article discusses the habitat selection of cetaceans and the potential impact of worsening freshwater flows and sea-level rise on waterways of the Sundarbans mangrove forest in Bangladesh. The surveys of waterways in the area revealed that Ganges River dolphin Platanista gangetica gangetica distribution was dependent on low salinity, high turbidity and high freshwater flow. Another data indicated significant differences between the actual and expected frequencies of Ganges River dolphin sightings.

Although habitat selection has been studied in a variety of snake taxa, little is known about habitat selection in aquatic snake species. Additionally, due to their small size and secretive nature, juvenile snakes are seldom included in habitat selection studies. The Eastern cottonmouth Agkistrodon piscivorus is a semi-aquatic pit viper known to use ambush, sit-and-wait foraging strategies. Ambush hunters are likely to select habitats that increase opportunity for successful prey capture while minimizing predation risk and maintaining appropriate thermal and hydric conditions. We characterized the foraging strategy and microhabitat use of cottonmouths at Ellenton Bay, an isolated Carolina bay freshwater wetland on the Savannah River Site in SC, USA. We measured habitat characteristics of 55 ambush sites used by 51 individual cottonmouths located during nighttime visual surveys, as well as 225 randomly selected sites within our search area. Cottonmouths exhibited an ontogenetic shift in foraging strategy with juveniles using predominately ambush foraging around the edge of the wetland while adults were most often encountered actively moving within the wetland. Principal components analysis revealed that juveniles selected foraging microhabitats that were different from random and consisted of mud substrate with sparse vegetation, whereas adults occupied a greater variety of microhabitats that did not differ from random. Concomitantly, free-ranging cottonmouths exhibited ontogenetic shifts in diet: juveniles consumed mostly salamanders, while adults ate a greater variety of prey including other snakes and birds. Our results highlight the importance of understanding how ontogenetic changes in coloration, diet and predation risk influence foraging strategy and microhabitat selection in snakes. [ABSTRACT FROM AUTHOR]

Theoretical work exploring dispersal evolution focuses on the emigration rate of individuals and typically assumes that movement occurs either at random to any other patch or to one of the nearest-neighbour patches. There is a lack of work exploring the process by which individuals move between patches, and how this process evolves. This is of concern because any organism that can exert control over dispersal direction can potentially evolve efficiencies in locating patches, and the process by which individuals find new patches will potentially have major effects on metapopulation dynamics and gene flow. Here, we take an initial step towards filling this knowledge gap. To do this we constructed a continuous space population model, in which individuals each carry heritable trait values that specify the characteristics of the biased correlated random walk they use to disperse from their natal patch. We explore how the evolution of the random walk depends upon the cost of dispersal, the density of patches in the landscape, and the emigration rate. The clearest result is that highly correlated walks always evolved (individuals tended to disperse in relatively straight lines from their natal patch), reflecting the efficiency of straight-line movement. In our models, more costly dispersal resulted in walks with higher correlation between successive steps. However, the exact walk that evolved also depended upon the density of suitable habitat patches, with low density habitat evolving more biased walks (individuals which orient towards suitable habitat at quite large distances from that habitat). Thus, low density habitat will tend to develop individuals which disperse efficiently between adjacent habitat patches but which only rarely disperse to more distant patches; a result that has clear implications for metapopulation theory. Hence, an understanding of the movement behaviour of dispersing individuals is critical for robust long-term predictions of population dynamics in fragmented landscapes. [ABSTRACT FROM AUTHOR]