bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climate change and contrasting plasticity in timing of a two-step migration episode of an Arctic-nesting avian herbivore
Authors: Fox Anthony David , Weegman Mitch D. , Bearhop Stuart , Hilton Geoff M. , Griffin Larry , Stroud David A. , Walsh Alyn 
Published: February 2016

Abstract
Greenland white-fronted geese Anser albifrons flavirostris wintering in Britain and Ireland migrate over the sea for 700–1200 km to stage 3–5 weeks in Iceland in spring, continuing a similar distance over the sea and Greenland Ice Cap to West Greenland breeding grounds. During 1969 to 2012, the geese advanced the mean departure date from Ireland by 15 days, during which time also they attained threshold fat stores earlier as well as departing in fatter condition. Over that period, Iceland spring-staging geese shifted from consuming underground plant storage organs to grazing managed hayfields, which provide fresh grass growth despite sub-zero temperatures, when traditional natural foods are inaccessible in frozen substrates. In 2012 and 2013, geese arrived three weeks earlier to Iceland, in fatter condition and accumulated fat significantly slower than in 1997–1999 and 2007. Although geese accumulated sufficient fat stores earlier in Iceland in 2007, 2012 and 2013, they departed around the same date as in 1997–1999, prolonging spring staging by three weeks. Plasticity in winter departure dates is likely due to improved winter feeding conditions (enabling earlier departure in better condition) and a novel predictable food resource in Iceland. Greenland white-fronted geese attained threshold fat stores in Iceland earlier, but remained rather than departing earlier to Greenland. Despite arriving earlier in Iceland, arrival dates on the breeding areas have not changed since the 1880s, presumably because of relatively constant cool springs and heavy snowfall in West Greenland during recent years.
Animal personality and the ecological impacts of freshwater non-native species
Authors: Juette Tristan , Cucherousset Julien , Cote Julien 
Published: February 2016

Abstract
While the ecological impacts of invasive species have been demonstrated for many taxonomic groups, the potential effects of behavioural variation among non-native individuals (i.e. personality) on these impacts have been largely overlooked. This is despite the fact that recent studies have demonstrated that, by nature, the three first stages of biological invasions (i.e. transport, establishment and spread) can lead to personality-biased populations. Freshwater ecosystems provide a unique opportunity to investigate this issue, notably because the ecological impacts of non-native species have been extensively documented and because animal personality has been widely studied using freshwater model species. Here, we aim at developing some perspectives on the potential effects of animal personality on the ecological impacts of freshwater non-native species across levels of biological organizations. At the individual level, personality types have been demonstrated to affect the physiolo- gy, metabolism, life history traits and fitness of individuals. We used these effects to discuss how they could subsequently impact invaded populations and, in turn, recipient communities. We also discussed how these might translate into changes in the structure of food webs and the functioning of invaded ecosystems. Finally we discussed how these perspectives could interact with the management of invasive species.
Woodland Mediterranean birds can resist a dry extreme cold wave
Authors: VilléN-Pérez Sara , Carrascal Luis M. 
Published: February 2016

Abstract
The ecological consequences of climate extreme events are still poorly understood, especially those related to cold episodes. Winter cold spells might imperil the energy balance of small passerines, thus compromising their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a montane oakwood of central Spain at ca. 1,300 m a.s.l. was influenced by the cold wave that hit Europe in February 2012. We monitored temperature, wind and the relative abundance of great tit Parus major, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods: before, during and after the cold wave. Our results clearly rule out widespread mortality and temporal migration of the studied passerine populations, as the abundance of these species did not diminish during the cold wave. Moreover, the species usually foraging higher in the tree canopy -and thus more exposed to wind-moved to the less windy woodland plots (long-tailed tit) and reduced their foraging height above ground during the cold wave (long-tailed tit and blue tit), probably to mitigate the deleterious effects of wind chill. Therefore, these forest birds were able to cope with a dry cold wave that was statistically extreme in terms of temperature and wind chill, according to the historic climate records of the region. It seems that, at least when foraging substrates are not heavily covered by snow or ice, Mediterranean birds can resist an extreme cold wave [Current Zoology 60 (4): 429–437, 2014].
Using the movement patterns of reintroduced animals to improve reintroduction success
Authors: Berger-TAL Oded , Saltz David 
Published: February 2016

Abstract
Despite their importance to conservation, reintroductions are still a risky endeavor and tend to fail, highlighting the need for more efficient post-release monitoring techniques. Reintroduced animals are released into unfamiliar novel environments and must explore their surroundings to gain knowledge in order to survive. According to theory, knowledge gain should be followed by subsequent changes to the animal’s movement behavior, making movement behavior an excellent indicator of reintroduction progress. We aim to conceptually describe a logical process that will enable the inclusion of behavior (in particular, movement behavior) in management decision-making post-reintroductions, and to do so, we provide four basic components that a manager should look for in the behaviors of released animals. The suggested components are release-site fidelity, recurring locations, proximity to other individuals, and individual variation in movement behavior. These components are by no means the only possible ones available to a manager, but they provide an efficient tool to understanding animals’ decision-making based on ecological theory; namely, the exploration-exploitation trade-off that released animals go through, and which underlies their behavior. We demonstrate our conceptual approach using data from two ungulate species reintroduced in Israel: the Persian fallow deer Dama mesopotamica and the Arabian oryx Oryx leucoryx [Current Zoology 60 (4): 515–526, 2014].
Time to feed: How diet, competition, and experience may influence feeding behaviour and cannibalism in wood frog tadpoles Lithobates sylvaticus
Authors: Jefferson Dale M. , Hobson Keith A. , Chivers Douglas P. 
Published: February 2016

Abstract
Wood frog Lithobates sylvaticus tadpoles develop in temporary wetlands where high population densities can force tadpoles into aggregations that intensify competition and can lead to cannibalism. However, chemical alarm cues released from injured conspecifics could also dissuade cannibalism. The purpose of this study was to test mechanisms that may influence cannibalistic behaviour. We tested whether the tendency of tadpoles to consume conspecifics would increase with the presence of competition and/or cues of profitable diets. Tadpoles placed in 1L experimental containers were tested for feeding initiation times of multiple diets, including conspecific tissues and conspecific tissues combined with chemical cues from the alternative diets (brine shrimp and cornmeal). Tadpoles were tested in the presence and absence of a competitor, and at multiple times over the course of the study. Tadpoles exhibited an altered response to diets over time; however the presence of a competitor reduced response times to all diets including conspecific tissues. Similarly, the presence of specific diets also reduced the response time of tadpoles to conspecific tissues. These results suggest competition among feeding tadpoles could result in aggressive behaviour leading to indiscriminate predation and cannibalism.
Individual consistency and sex differences in migration strategies of Scopoli’s shearwaters Calonectris diomedea despite year differences
Authors: Müller Martina S. , Massa Bruno , Phillips Richard A. , Dell’omo Giacomo 
Published: February 2016

Abstract
Recently-developed capabilities for tracking the movements of individual birds over the course of a year or longer has provided increasing evidence for consistent individual differences in migration schedules and destinations. This raises questions about the relative importance of individual consistency versus flexibility in the evolution of migration strategies, and has implications for the ability of populations to respond to climatic change. Using geolocators, we tracked the migrations of Scopoli’s shearwaters Calonectris diomedea breeding in Linosa (Italy) across three years, and analysed timing and spatial aspects of their movements. Birds showed remarkable variation in their main wintering destination along the western coast of Africa. We found significant individual consistency in the total distance traveled, time spent in transit, and time that individuals spent in the wintering areas. We found extensive sex differences in scheduling, duration, distances and destinations of migratory journeys. We also found sex differences in the degree of individual consistency in aspects of migration behaviour. Despite strong evidence for individual consistency, which indicates that migration journeys from the same bird tended to be more similar than those of different birds, there remained substantial intra-individual variation between years. Indeed, we also found clear annual differences in departure dates, return dates, wintering period, the total distance traveled and return routes from wintering grounds back to the colony. These findings show that this population flexibly shifts migration schedules as well as routes between years in response to direct or indirect effects of heterogeneity in the environment, while maintaining consistent individual migration strategies.
Human activity affects the perception of risk by mule deer
Authors: Price Mary V. , Strombom Evelyn H. , Blumstein Daniel T. 
Published: February 2016

Abstract
Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity—a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance; FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching plateaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial “human footprint” on behavior may be useful for understanding how human activities affect wildlife.
Living on the edge: Effects of body size, group density and microhabitat selection on escape behaviour of southern leopard frogs Lithobates sphenocephalus
Authors: Bateman Philip W. , Fleming Patricia A. 
Published: February 2016

Abstract
Models of optimal escape strategy predict that animals should move away when the costs of fleeing (metabolic and opportunity costs) are outweighed by the costs of remaining. These theoretical models predict that more vulnerable individuals should be more reactive, moving away when an approaching threat is further away. We tested whether escape behaviour (including ‘escape calling’) of Lithobates sphenocephalus approached by a human was influenced by body size or the initial microhabitat that the individual was found in. Irrespective of their size, frogs in the open tended to remain immobile, enhancing their crypsis. Frogs in cover showed different responses according to their body size, but, contrary to our initial predictions, larger frogs showed greater responsiveness (longer flight initiation distance and distances fled) than small frogs. Small frogs tended to remain closer to water and escaped into water, while larger individuals were more likely to jump to terrestrial cover and call during escape. Density of frogs near the focal animal had no effect on escape behaviour. This study indicates a range of escape responses in this species and points to the importance of divergent escape choices for organisms which live on the edge of different environments.
An evolutionary perspective on conflict and compensation in physiological and functional traits
Authors: Husak Jerry F. , Lailvaux Simon P. 
Published: February 2016

Abstract
Physiological and functional traits, especially those related to behavior and whole-organism performance capacities, are subject to a variety of both parallel and opposing natural and sexual selection pressures. These selection pressures show considerable interspecific variation, shaping contemporary behavioral and functional diversity, but the form and intensity of selection on physiological and functional traits can also vary intraspecifically. The same suites of traits can experience quite different selection pressures, depending on the sex or age of a given individual, as well as the presence and nature of alternative reproductive strategies and tactics. These interand intra-locus genetic conflicts have potentially important consequences for the evolutionary trajectories of traits subject to them. Consequently, any intraspecific conflicts which could displace traits from their selective optima in certain classes of individuals relative to others are expected to result in selection for mechanisms to compensate for deviation from those optima. Such conflicts include interlocus sexual conflict, intralocus sexual conflict, and interacting phenotypes, as well as conflict within a sex. In this paper, we consider the evidence for, and implications of, such conflicts for physiological and functional traits in diverse taxa, including both vertebrates and invertebrates, and evaluate the various mechanisms, ranging from behavioral and mechanical to energetic and genetic, enabling compensation. We also discuss how preand post-mating conflicts, as well as interacting phenotypes, might affect the evolution of behavior and physiological and functional traits. Investigators that seek to understand the links among behavior, morphology, physiology, and function should consider such conflicts.
Annoying neighbors: Multi-scale distribution determinants of two sympatric sibling species of birds
Authors: Guillaumet Alban , Leotard Guillaume 
Published: February 2016

Abstract
We tested the role of interspecific competition in driving species distribution at multiple spatial scales using two sibling species of Galerida larks (G. cristata and G. theklae) in Morocco (sympatry), Balearic islands (G. theklae only) and Israel (G. cristata only). We first investigated regional-scale determinants by contrasting allopatric versus sympatric patterns in five distinct habitat types. We next focused on a single habitat used by both species, the coastal sand dunes. Dune quadrats were established along the Moroccan coast and completed by a quadrat in the nearest distinct landscape habitat. Poisson regressions were used to model Galerida counts together with ecological predictors as concerns the climate, topography, vegetation structure and soil gra-nulometry. At the local scale, both species preferred grey dunes over white sand dunes, and both were negatively affected by the abundance of the congeneric species in the dune. However, we found that G. theklae tended to replace G. cristata in more arid sand dunes, even if the transition was not strictly clinal. Instead, the transition occurred when the surrounding landscape changed from coastal wetlands to bathas (grasslands with shrubs), highlighting the importance of habitat composition at the landscape scale. The fact that G. cristata used bathas in allopatry, but not in sympatry, suggested that the competitive environment contributed to determine sand dune occupancy. We suggest that landscape-level effects may be pivotal in explaining species distribution not only at the local scale, by affecting the pool of potential immigrants, but also at the regional scale, by contributing to species’ range limit.
The effect of social context and social scale on the perception of relationships in monk parakeets
Authors: Hobson Elizabeth A. , John Darlene J. , Mcintosh Tiffany L. , Avery Michael L. , Wright Timothy F. 
Published: February 2016

Abstract
Social relationships formed within a network of interacting group members can have a profound impact on an individual’s behavior and fitness. However, we have little understanding of how individuals perceive their relationships and how this perception relates to our external measures of interactions. We investigated the perception of affiliative and agonistic relationships at both the dyadic and emergent social levels in two captive groups of monk parakeets (Myiopsitta monachus, n = 21 and 19) using social network analysis and playback experiments. At the dyadic social scale, individuals directed less aggression towards their strong affiliative partners and more aggression towards non-partner neighbors.At the emergent social scale, there was no association between relationships in different social contexts and an individual’s dominance rank did not correlate with its popularity rank. Playback response patterns were mainly driven by relationships in affiliative social contexts at the dyadic scale. In both groups, individual responses to playback experiments were significantly affected by strong affiliative relationships at the dyadic social scale, albeit in different directions in the two groups. Response patterns were also affected by affiliative relationships at the emergent social scale, but only in one of the two groups. Within affiliative relationships, those at the dyadic social scale were perceived by individuals in both groups, but those at the emergent social scale only affected responses in one group. These results provide preliminary evidence that relationships in affiliative social contexts may be perceived as more important than agonistic relationships in captive monk parakeet groups. Our approach could be used in a wide range of social species and comparative analyses could provide important insight into how individuals perceive relationships across social contexts and social scales.
Understanding the evolution of learning by explicitly modeling learning mechanisms
Authors: Arbilly Michal 
Published: February 2016

Abstract
Models of the evolution of learning often assume that learning leads to the best solution to any task, and disregard the details of the learning and decision-making process along with its potential pitfalls. These models therefore do not explain instances in the animal behavior literature in which learning leads to maladaptive behaviors. In recent years a growing number of theoretical studies use explicit models of learning mechanisms, offering a fresh perspective on the issue by revealing the dynamics of information acquisition and biases arising from it. These models have pointed out possible learning rules and their adaptive value, and shown that the value of learning may crucially depend on such factors as the layout of the physical environment to be learned, the structure of the payoffs offered by different alternatives, the risk of failure, characteristics of the learner and social interactions. This review considers the merits of explicit modeling in studying the evolution of learning, describes the kinds of results that can only be obtained from this modeling approach, and outlines directions for future research.
Boldness and predator evasion in naturally hybridizing swordtails (Teleostei: Xiphophorus)
Authors: Johnson James B. , Culumber Zachary W. , Easterling Ryan , Rosenthal Gil G. 
Published: February 2016

Abstract
Correlations among behavioral traits can generate trade-offs and constrain phenotypic evolution. Interspecific hybridization has the potential to alter behavioral trait correlations, but the effect of hybridization on suites of behavioral traits has received relatively little attention. We evaluated how natural hybridization changes the relationship between boldness (time of emergence and proportion of time out of shelter) and response to a simulated predator threat in swordtails (Teleostei: Xiphophorus). In poeciliid fishes, bold individuals have increased survival in the presence of predators. This non-intuitive observation may arise as a result of bold individuals being more likely to engage in anti-predator behaviors. Contrary to our prediction, bold individuals were less likely to perform a fast-start response to a predator threat. This correlation was consistent among populations and species but was only significant in hybrids. The observed correlation between boldness and anti-predator behavior could impact hybrid fitness and the evolvability of hybrid lineages. More generally, our findings suggest that hybridization could influence the integration of behavioral phenotypes, as has been amply documented for morphology. Animal personality and behavioral syndromes could therefore play an important role in the evolutionary fate of natural hybrids.
Flexible mating tactics and associated reproductive effort during the rutting season in male reindeer (Rangifer tarandus, L. 1758)
Authors: Pintus Eliana , Uccheddu Stefania , Røed Knut H. , Gonzaléz Javier Pérez , Carranza Juan , Nieminen Mauri , Holand Øystein 
Published: February 2016

Abstract
Polygynous males can change their mating tactics across their lifetime, but information is scarce on the flexibility of this trait within a given season and the relative costs and benefits of using different tactics. Here, we monitored individually marked male reindeer Rangifer tarandus and classified their mating tactics as harem-defense, sneaking, or mixed. The costs of the male reproductive effort were assessed using both direct (i.e. percentage of body mass lost) and indirect measures (i.e. activity patterns such as feeding, standing, and walking), while mating group size and reproductive success were recorded as mating effort benefits. Our results show that reindeer males may switch between the harem-defense and sneaking tactics throughout the same breeding season, providing further support to the notion that reproductive tactics are flexible in ungulates. The costs and benefits of male mating effort vary according to the mating tactic, reaching the highest values in harem-holders and the lowest values in sneaking males. Moreover, males who switched between the sneaking tactic and the harem-defence tactic tended to achieve higher mating success than males who consistently used the least costly tactic. Indeed, all harem-holders successfully sired offspring, whereas only two out of three mixed-tactic males sired one calf, and sneaking males did not sire any calves. In conclusion, our results show that reindeer males can modulate their mating efforts during the same breeding season by switching between the most costly harem-defense tactic and the least costly sneaking tactic, suggesting individual solutions to the balance between reproductive effort and mating opportunities.