Vertical Space Use Research Articles

Influence of later exposure to perches and nests on flock level distribution of hens in an aviary system during lay

Aviaries provide hens with many resources, but birds must develop motor and cognitive skills to use them properly. Introducing birds to aviaries at older ages has been reported to result in less use of perches, nests, and vertical space, which can reduce productivity and hen welfare. The objectives of this study were to examine (1) how enrichment influenced distribution of hens in the aviary during the day and (2) how enrichment influenced the distribution and roosting substrate of birds at night. Hy-Line W36 pullets were raised in floor pens before moving to laying aviaries (100 hens/aviary unit × 4 units/treatments). Control (CON) pullets were placed into aviaries at 17 wk of age (WOA). Floor (FLR) and enriched (ENR) pullets remained in floor pens until 25 WOA, and ENR birds were provided with perches and nests at 17 WOA. Birds were counted in tiers and litter areas of the aviary at morning, midday and evening at 36 and 54 WOA. Data were analyzed using generalized linear mixed models in R statistical software. At 36 WOA, ENR and CON birds occupied aviary areas at similar rates but differently from FLR birds. For example, in the morning 34% of CON hens and 30% of ENR hens occupied the highest tier compared to 15% of FLR hens (P < 0.01). At midday, 57% of CON and 57% of ENR birds were counted in litter compared with 77% of FLR birds (P < 0.01). In the evening, CON and ENR hens moved to the top tier of the aviary in greater numbers than FLR hens (22 and 17%, respectively, vs. 7%, P < 0.01). At 54 WOA, differences between FLR hens and CON/ENR hens were less pronounced, suggesting FLR hens were adapting to the aviary. Overall, we conclude that birds exposed to aviaries at 25 WOA can adapt to aviary systems, but take more time to do so than birds exposed to aviaries or vertical enrichment at 17 WOA.

Later exposure to perches and nests reduces individual hens' occupancy of vertical space in an aviary and increases force of falls at night

Tiered aviaries are intended to improve laying hen welfare by providing resources that enable them to perform essential behaviors. However, hens must be able to navigate these complex systems efficiently and safely. This study investigated the influence of providing perches and nests starting at 17 or 25 wk of age (WOA) on hens' use of vertical space in an aviary at 36 and 54 WOA. Three treatments were applied to pullets raised in floor pens until 17 WOA (4 units/treatment; 100 hens/unit). Control (CON) pullets were placed into aviaries at 17 WOA. Floor (FLR) pullets were placed into aviaries at 25 WOA. Perches and nests were placed in enriched (ENR) pullets' floor pens at 17 WOA prior to moving ENR birds to aviaries at 25 WOA. Five focal hens/unit (n = 20 total hens/treatment) were fitted with accelerometers, and their diurnal movement (g) and frequency (n) and acceleration (g) of falls at night were recorded. Direct observation of focal hens was conducted for 6 min/hen at morning, midday, and evening for 3 consecutive days at 36 and 54 WOA, and location and time spent on vertical tiers were recorded. At 36 WOA, FLR hens spent more time on litter than CON and ENR, which spent more time in the top tier (all P ≤ 0.05). ENR hens exhibited higher vertical movement than CON and FLR hens (0.8, 0.6, and 0.3 g; P = 0.003). CON hens fell most often at night (16 vs. 9 FLR and 5 ENR), whereas FLR hens had higher acceleration and calculated collision force than CON and ENR hens during falls (0.8, 0.5, 0.3 g and 15, 10, 5 N, respectively; P ≤ 0.05). At 54 WOA, hens' movement and vertical distribution were similar across treatments. Delaying birds' access to perches and nests until 25 WOA impacted their movement, vertical space use, and falls at night for at least 10 wk. However, providing perches and nests at 17 WOA, even in floor pens, considerably mitigated such impacts.

Seasonal changes in basking shark vertical space use in the north-east Atlantic

Mobile marine species can exhibit vast movements both horizontally and vertically. Spatial analysis of vertical movements may help improve an understanding of the processes that influence space use. Previously, vertical space use of basking sharks (Cetorhinus maximus) in the north-east Atlantic described movements largely within waters of the continental shelf during summer and autumn months, with few records of detailed vertical behaviour during winter. We use archival satellite telemetry data from 32 basking sharks (12 females, 6 males, and 14 of unknown sex measuring 4–5 m (n = 6), 5–6 m (n = 10), 6–7 m (n = 7), 7–8 m (n = 8), and 8–9 m (n = 1) estimated total length) tracked over 4 years (2012–2015). The satellite tags provided depth and temperature data for a cumulative 4489 days (mean 140 ± 97 days per shark, range 10–292 days) to describe vertical space use and thermal range of basking sharks in the north-east Atlantic. Basking sharks exhibit seasonality in vertical space use, revealing repeated ‘yo-yo’ movement behaviour with periods of occupancy at depths greater than 1000 m in late winter/early spring. Describing seasonal vertical space use in marine megavertebrates can increase knowledge of movements throughout their environment including physiological and morphological constraints to movement, nutrient transfer, and overlap with anthropogenic threats to inform future conservation strategies.

Survival, behaviour, and morphology of larval wood frogs, Lithobates sylvaticus, under threat from an exotic crayfish predator, Orconectes virilis

There are numerous examples of species introductions that have caused declines in native populations. In many cases, exotic species are predators of native prey which do not respond correctly to these new and often much different threats. Amphibians, as a group, have been strongly affected by introductions of fish and other aquatic predators such as crayfish. Our goal in this study was to explore the potential impacts of exotic crayfish on the behaviour, morphology, and survival of naive wood frog tadpoles, Lithobates sylvaticus. In mesocosms, groups of tadpoles were exposed to either a native predator (larval beetle or dragonfly nymph) or an exotic crayfish, Orconectes virilis. Tadpoles were the largest following exposure to dragonflies, indicating that dragonflies were selecting smaller tadpoles. Vertical space use of tadpoles was highest in the presence of crayfish, suggesting that tadpoles were learning to avoid crayfish in the benthos. Mortality was highest in the presence of beetles and lowest with crayfish, and hence in isolation, exotic crayfish were poorer predators of wood frog tadpoles. However, half way through the experiment, we replaced each predator with a new predator of either the same species or a different species to assess how the impact of the new predator was affected by experience with the first predator. When crayfish were added following beetles, the mortality due to crayfish increased significantly, possibly due to differences in predator space use and foraging mode.

Availability of food resources and habitat structure shape the individual-resource network of a Neotropical marsupial.

Spatial and temporal variation in networks has been reported in different studies. However, the many effects of habitat structure and food resource availability variation on network structures have remained poorly investigated, especially in individual‐based networks. This approach can shed light on individual specialization of resource use and how habitat variations shape trophic interactions.To test hypotheses related to habitat variability on trophic interactions, we investigated seasonal and spatial variation in network structure of four populations of the marsupial Gracilinanus agilis in the highly seasonal tropical savannas of the Brazilian Cerrado.We evaluated such variation with network nestedness and modularity considering both cool‐dry and warm‐wet seasons, and related such variations with food resource availability and habitat structure (considered in the present study as environmental variation) in four sites of savanna woodland forest.Network analyses showed that modularity (but not nestedness) was consistently lower during the cool‐dry season in all G. agilis populations. Our results indicated that nestedness is related to habitat structure, showing that this metric increases in sites with thick and spaced trees. On the other hand, modularity was positively related to diversity of arthropods and abundance of fruits.We propose that the relationship between nestedness and habitat structure is an outcome of individual variation in the vertical space and food resource use by G. agilis in sites with thick and spaced trees. Moreover, individual specialization in resource‐rich and population‐dense periods possibly increased the network modularity of G. agilis. Therefore, our study reveals that environment variability considering spatial and temporal components is important for shaping network structure of populations.

Forest Land Tenure Rights on Indigenous Peoples in Honitetu Village West Seram District, Maluku

Forest land tenure systems for indigenous peoples are always debated by various parties regarding the overlapping interests and rights of forest land. Objective of this study is to analyze the types of indigenous peoples' rights to strengthen forest land tenure systems in Honitetu Village, West Seram Regency. The research approach used is Participatory Action Research by building constructs of meaning between researchers and society repeatedly to obtain an understanding of the information discussed. Data were obtained through key informant interviews and focus group discussions conducted repeatedly. The analysis was carried out at each stage of the interview and discussion by making categorization of data to get an understanding of each data obtained. The results of study show that the system of forest land tenure in indigenous communities in Honite village includes control by the whole community (petuanan), control by clan groups (soa) and control by individuals (families). In these three systems, various types of rights are attached to managing and utilizing forest resources. The set of rights contained in indigenous peoples will be even stronger if it includes the linkage of longtime dimensions, the dimensions of space for the use of vertical or horizontal space, the dimensions of the subject with fixed ownership and the dimensions of the object include the results of forest land that provides full benefits.Key words: forest land tenure rights, indigenous people, forest management

Activity seascapes highlight central place foraging strategies in marine predators that never stop swimming

BackgroundCentral place foragers (CPF) rest within a central place, and theory predicts that distance of patches from this central place sets the outer limits of the foraging arena. Many marine ectothermic predators behave like CPF animals, but never stop swimming, suggesting that predators will incur ‘travelling’ costs while resting. Currently, it is unknown how these CPF predators behave or how modulation of behavior contributes to daily energy budgets. We combine acoustic telemetry, multi-sensor loggers, and hidden Markov models (HMMs) to generate ‘activity seascapes’, which combine space use with patterns of activity, for reef sharks (blacktip reef and grey reef sharks) at an unfished Pacific atoll.ResultsSharks of both species occupied a central place during the day within deeper, cooler water where they were less active, and became more active over a larger area at night in shallower water. However, video cameras on two grey reef sharks revealed foraging attempts/success occurring throughout the day, and that multiple sharks were refuging in common areas. A simple bioenergetics model for grey reef sharks predicted that diel changes in energy expenditure are primarily driven by changes in swim speed and not body temperature.ConclusionsWe provide a new method for simultaneously visualizing diel space use and behavior in marine predators, which does not require the simultaneous measure of both from each animal. We show that blacktip and grey reef sharks behave as CPFs, with diel changes in activity, horizontal and vertical space use. However, aspects of their foraging behavior may differ from other predictions of traditional CPF models. In particular, for species that never stop swimming, patch foraging times may be unrelated to patch travel distance.

Biodiversity: Complementary canopies.

Physical complementarity among trees in the use of vertical space increases productivity due to species-specific differences and plasticity in crown architecture.

Development of perching behavior in 3 strains of pullets reared in furnished cages

Furnished rearing cages are becoming more widely available to replace conventional systems for pullets. To date, there is little information on how pullets develop perching behavior in furnished cages or how this varies among strains. The objective of this study was to evaluate the use of perches and a platform in a commercial furnished rearing “Combi-Cage” system by 3 pure-bred heritage strains of pullets (Rhode Island Red, Columbian Rock, and White Leghorn). Each cage had 4 elevated locations: one platform and 3 perches of differing heights and positions in the cage. The length of each cage was visually divided into 4 sections for observation. The number of birds using each section in each location was counted by one observer d per wk at 1200 h (d) from one to 14 wk of age and at 1600 h (night) right after lights were turned off from 4 to 14 wk of age. Mixed model repeated analyses were used to test effects of strain, age, and their interaction on the use of the platform, the 3 perches, and all 4 locations combined (vertical space use) at both time periods. GLM were used to compare overall use of the sections and locations. On average, pullets used vertical space more during the d than at night. There were also effects of age (P < 0.05) and strain (P < 0.05) on the use of the 4 locations in the cage at both time periods. Generally, the Columbian Rocks used the perches and platform the most, and Rhode Island Reds the least. The highest perch in the cage was rarely used and birds showed a preference for perching in sections that were closest to cage walls (P < 0.05). Differences across strains and low use of some perch locations indicate that the design of furnished rearing cages may still require improvements in order to ensure the furnishings are used by pullets as intended.

Evaluating riverine hydrokinetic turbine operations relative to the spatial ecology of wild fishes

ABSTRACTHydrokinetic turbines (HTs) are being proposed for placement in riverine landscapes around the globe. Here, we implanted 40 adult lake sturgeon and 40 adult walleye with acoustic telemetry transmitters to monitor their lateral and vertical space use at the Canadian Hydrokinetic Turbine Testing Centre (CHTTC) located in the Seven Sisters Generating station (GS) tailrace on the Winnipeg River, Manitoba. Specifically, we tested whether fish behaviour was influenced by the operation of HTs relative to control periods, and estimate the threat of HTs towards lake sturgeon and walleye across seasons. The behaviour and habitat use of both species was not influenced by HT operations. Greater numbers of walleye were present when the discharge rate was ≥ 950 m3s–1, which is ≥ 77 m3s–1 greater than the average discharge rate (873 m3s–1) measured during the study period. Given the patterns of seasonal residency, movement, and depth use, lake sturgeon appeared more prone to interacting with HTs during spring and early summer months (i.e. May and June), whereas risk to walleye would be highest throughout the summer and autumn months. In the vicinity of the acoustic receivers, available habitat (areas with large boulders, and transitions between swift flow in the channel and slacker water near the shoreline) was used significantly more often by walleye than lake sturgeon. Lake sturgeon utilized similar depths where HTs would be installed (i.e. ≥ 6.5 m), while walleye commonly occupied shallower depths at the HT testing centre making the former more susceptible to interactions with substrate-HT's. Collectively, these are some of the first field-based results on fish behaviour and ecology while a riverine-HT is in operation. The findings present useful information to help guide best practices for commercial scale HT operations within river systems where lake sturgeon and walleye reside.

Contrasting patterns of vertical and horizontal space use of two exploited and sympatric coral reef fish

Understanding spatial distribution and temporal variation in movement patterns of closely related species is relevant for deciphering how resources are selected and whether interactions between species affect resource use patterns. The horizontal space use and vertical space use of two exploited reef fish, Plectropomus leopardus and P. laevis (all adults), were compared at mid-shelf Helix Reef and Lodestone Reef in the Great Barrier Reef over ~3 years using passive acoustic telemetry. Both species were detected throughout the 12-month duration of transmitters (mean detection period: ~270 days) and often made deep movements to ~40 m possibly related to reproductive behaviour (spawning). Differences in space use were apparent between species, with P. laevis consistently using greater area around reefs throughout the year. Overall, depth use patterns were similar between species; however, when daily detections were grouped in 2-h periods, P. laevis remained shallower and had greater variation in depth use compared to P. leopardus. Contrasting patterns of space use between these co-occurring species, in conjunction with known dietary dissimilarities, indicate distinct habitat use and resource preferences that are important for conservation and fisheries management.

Assessing fine-scale diel movement patterns of an exploited coral reef fish

Understanding movement patterns of species requires that the spatial and temporal scales of experimental designs are appropriate to the proposed ecological questions. Previous research on large-scale movements of the exploited reef fish Lethrinus miniatus suggested that adult individuals may use coral reef slope habitat during the day, shifting to adjacent deeper sandy habitat at night. However, investigation of movement at a fine spatial and temporal scale is required to verify this diel activity pattern. Using a closely positioned acoustic telemetry system, movements of 11 L. miniatus were monitored among habitats from the reef crest, to reef slope and deeper adjacent sandy habitat over 3 months. Fine-scale movement patterns among these habitats were compared among four different 3 h periods of the day: dawn, day, dusk and night. Initial observations demonstrated significantly larger horizontal core areas and vertical areas of extent during crepuscular and night periods compared to during the day. Vertical space use (core area and extent) was consistently larger during dawn, dusk and night compared to during the day. Area of activity space extent within the water column and proportional overlap among areas used during different periods of the day varied among weeks, and displayed a pattern consistent with full moon periods. Although previous evidence suggested that L. miniatus adults may shift to deeper habitats adjacent to the reef slope at night, greater space use across the shallow crest to deeper sand habitat was observed during dawn, dusk and night periods. Increased luminosity during dawn, dusk and night periods may cause L. miniatus to utilise a larger search area for foraging. While further research is required to confirm foraging during the hours of twilight and darkness, this fine-scale approach identified patterns in nocturnal activity for an important reef teleost. Knowledge of these temporal and spatial differences in L. miniatus behaviour and movement are important to understanding how this species coexists within ecological niches.

Patterns in the use of rainforest vertical space by Neotropical aerial insectivorous bats: all the action is up in the canopy

In tropical rainforests environmental conditions vary dramatically from the ground to the canopy, resulting in a marked stratification in the way vertical space is used by organisms, but research work is often limited to the understorey layer. Aerial insectivorous bats are a highly diverse group that plays key roles in the ecology of rainforests, but their use of vertical space remains elusive.Using automatic ultrasound recording stations placed in the canopy, subcanopy and understorey we tested if bat activity and species diversity are vertically stratified, both in the forest interior and near the edges of water bodies. These patterns were tested separately for individual species, and for two functional groups – open space and edge space bats.Insectivorous bat activity increased by roughly seven fold, and species diversity doubled, from the understorey to the canopy. Both edge space and open space bats were more active in the upper strata, but this tendency was much more accentuated in the latter. Myotis riparius was the only species with greater activity near the understorey. These patterns were altered at the edges of water bodies, where vertical stratification was much less marked.The observed patterns are parsimoniously explained by constraints imposed by vegetation clutter that change across strata, which affect bat species differently. Only bats better adapted to closed spaces are usually capable of foraging within the understorey, whereas the majority of species can exploit the free spaces immediately below the canopy; open space bats seem to concentrate their activity above the canopy. This importance of the inter strata open spaces for bat foraging highlights the need to preserve pristine stratified rainforests, as even selective logging usually disrupts vertical stratification. Moreover, the concentration of insectivorous bats at the upper strata of rainforests underlines the need to include canopy level sampling in ecological studies.

Vertical habitat segregation as a mechanism for coexistence in sympatric rodents

Coexistence has been widely studied in small mammals and frequently is assumed to be facilitated by habitat segregation. Using live trapping and spool-and-line experiments, we analyzed habitat selection and segregation across multiples scales for Peromyscus leucopus and Ochrotomys nuttalli. At the habitat scale of a forest stand (∼1–100sha) P. leucopus co-occurred at all sites where O. nuttalli was found, and we did not detect evidence of positive or negative associations or habitat segregation. However, O. nuttalli was restricted to early successional forests, and P. leucopus had significantly lower abundances in early successional forests than in other habitats. We found similar patterns at the mesohabitat scale of the study site (400m2). O. nuttalli abundance increased with increasing shrub and tree densities, while increases in P. leucopus abundance were associated with open understories. At the microhabitat scale of the individual movement trail, we found vertical segregation. Movement trails for O. nuttalli were at significantly higher elevation (mean height=142.93±37.10cm) than P. leucopus trails (mean height=15.4±4.98cm; F-value=35.29, p<0.001). We concluded that microhabitat segregation was driven by differential use of vertical space for movement and foraging. We suggest O. nuttalli is superior to P. leucopus in its ability to acquire food especially in shrubby subcanopies where few acorns are available. However, P. leucopus is superior in its ability to forage and avoid predators.

Small mammal community structure and vertical space use preferences in nonfragmented Atlantic Forest

Here we describe a small mammal community in nonfragmented Atlantic Forest in southern Brazil. A total of 146 individuals were live captured on the ground and in trees (total effort: 5600 trap-nights). Twelve species were identified by morphology, and identification of seven species was confirmed by DNA barcoding. Most species were terrestrial, with Euryoryzomys russatus being the most frequently captured, while the rodent Juliomys pictipes was semiarboreal and the marsupial Marmosa paraguayana was arboreal. With the capture of Trinomys iheringi, we extend the species distribution to the south. Species favored in disturbed environments as Oligoryzomys spp. and Akodon spp. were uncommon, and this small mammal community is typical of a well-conserved forest.

Temporal Variation in Flock Size and Habitat Use of Parrots in New Caledonia

Abstract. We examined daily activity patterns, flock-size variations, use of vertical space, and small-scale habitat selection of the New Caledonian Parakeet (Cyanoramphus saisseti), Horned Parakeet (Eunymphicus cornutus), and New Caledonian Rainbow Lorikeet (Trichoglossus haematodus deplanchii) on mainland New Caledonia. All three species had bimodal patterns of activity, with most encounters occurring in the morning and a second smaller peak of encounters in the late afternoon. The parakeets were usually seen singly or in twos, and most flocks contained fewer than four individuals. Parakeet flocks remained relatively consistent in size through the day and through the year. Most Rainbow Lorikeet flocks contained only a few individuals, though some reached up to 40 birds. Rainbow Lorikeets were encountered mainly in small flocks during the breeding season from September to January, and their average flock size was higher and more variable for the rest of the year. Rainbow Lorikeets selected valley forest ...

Which forest bird species are the main hosts of the tick, Ixodes ricinus, the vector of Borrelia burgdorferi sensu lato, during the breeding season?

Wild birds are important hosts for vector–borne pathogens, especially those borne by ticks. However, few studies have been conducted on the role of different bird species within a community as hosts of vector–borne pathogens. This study addressed individual and species factors that could explain the burden of Ixodes ricinus on forest birds during the reproductive periods of both vectors and hosts. The goal was to identify which bird species contribute the most to the tick population at the community level. Birds were mist-netted on four plots in 2008 and on seven plots in 2009 in two forests (Sénart and Notre Dame, near Paris, France). The dependence of the tick load per bird upon environmental conditions (questing nymph density, year and plot) and on host species traits (species, age, sex, body size, vertical space use, level of innate and acquired immunity) was analysed. Finally, the relative contribution of each bird species to the local dynamics of ticks was estimated, while accounting for their respective abundance. Tick burden differed markedly between bird species and varied according to questing nymph density. Bird species with a high body mass, those that forage low in the vegetation, and those that had a high innate immune response and a high spleen mass were more likely to have a high tick burden. Four species (the Common Blackbird, Turdus merula, the European Robin, Erithacus rubecula, the Song Thrush, Turdus philomelos, and the Winter Wren, Troglodytes troglodytes) hosted more than 90% of the ticks in the local bird community. These species, and particularly T. merula which was host to a high proportion of the nymphs, are likely to contribute significantly to the circulation of pathogens for which they are competent, such as the agent of Lyme borreliosis.

Correlation between Underground Space Intensity and Land-Use Transport Interaction

Urban planning for vertical space use must consider underground space form and intensity. But little researches and investigations about it have been done. Planners have little knowledge about quantitative mechanism of underground space developing and evolution. Advanced countries developed experienced data of underground space distribution. Modern statistical analysis method provides an efficient tool for this kind of quantitative and empirical research of spatial correlation. This paper selected some of the major characteristic indexes of land-use transport interaction and induces spatial statistical model to analyze the correlation between intensity of underground space use and the indexes of land-use transport interaction in central four districts of Tokyo City. Results show that the intensity of underground space use has positive and stable quantitative correlations with land use function (LT), land price (LP) and floor area ratio (FAR), especially significant in commercial and mixed land-use areas. The influencing factors of land-use transport interaction could be used as external indexes for forecasting the intensity and spatial distribution of underground space in urban central areas.

Approches de la langue parlée en français par Claire Blanche-Benveniste

Linguistics edited by Stacey Katz Bourns BLANCHE-BENVENISTE, CLAIRE. Approches de la langue parlée en français. Paris: Ophrys, 2010. ISBN 978-2-7080-1278-3. Pp. 175. 16 a. The relationship between spoken and written language, as clearly illustrated by Blanche-Benveniste, is nuanced and complex. Moreover, she affirms that the study of spoken French paradoxically relies on the written word for interpretation and analysis. In the case of this particular work, a considerably updated edition of the 1997 book of the same title, the written word elucidates, exemplifies, provokes and calls for action in a relatively compact form. The author claims to present only a small portion of the research in the field, specifically those contributions of GARS (Groupe Aixois de Recherches en Syntaxe). In many ways, however , this book could be considered an abbreviated and approachable state of the art. For instance, Blanche-Benveniste methodically acknowledges popular notions or prejudices, such as the idea that spoken language is inextricably linked with mistakes, and then refutes them with examples and tests. Throughout the work, she returns to bigger questions, such as: Who really uses certain varieties of language? What can our intuition do for us? Where do difficulties in interpretation lie? What can the study of spoken French do for the understanding of the French language overall? Furthermore, overlapping and potentially troublesome terminology, such as noyau versus rhème, is presented, exemplified, and contrasted , and these terms are then made available in a glossary. Altogether, the book is highly readable, with thought-provoking prose and numerous relevant, interesting, and clear examples, most of which come from the corpus collected at the University of Provence. The use of vertical space for analysis aids the reader in seeing patterns in line with the argumentation. It also invites the reader to appreciate that elements of spoken language that have often been dismissed as irrelevant or incoherent can actually be of interest. These attributes make this book a good choice for the uninitiated as well as a useful reference for the more advanced scholar. Additionally, while all the examples and analysis are tied specifically to French, an underlying universality becomes apparent when the work is read as a whole. The chapters of this updated version maintain the same organization as its predecessor; however, the content is significantly revised, with the integration of many new references (approximately thirty works added to the bibliography) and discussions of recent research throughout, effectively situating the work in the academic landscape. In the early chapters, Blanche-Benveniste discusses the relationship between spoken and written language and addresses ways of classifying spoken language. She refutes reductionist dichotomies and instead embraces the complexities of a continuum. Chapter 3 serves as an introduction to the rest of the book by outlining the argumentation and methods of analysis: the grammar of written French is adequate and even enhanced by the inclusion of spoken data in the domains of syntax and macro-syntax, but not morphology, due to its reliance on orthography. This third chapter is the least cohesive of the book and ends rather abruptly with a series of documents exemplifying how technology has enhanced the analysis of spoken corpora. In fact, it could be better followed by chapter 6, which gives the reader a closer look at analysis of oral texts. Chapters 4 and 5, in contrast, could each stand alone and constitute 800 FRENCH REVIEW 85.4 provocative readings for an advanced seminar in French language. A recurrent message throughout the book is that in order to make progress in the study and description of spoken French, there is an urgent need for a much larger and diverse corpus similar to those available in other European languages. The reader learns in a foreword written by the series editor that Blanche-Benveniste died after submitting the last corrections for this edition, further reinforcing her ardent call for different angles of observation to achieve true progress in French language studies. University of Missouri, Kansas City Lindsy L. Myers CELLARD, KARINE, et KARIM LAROSE, éd. La langue au quotidien: les intellectuels et le français dans la presse québécoise—Anthologie, Volume 1. Québec: Nota Bene, 2010. ISBN 978...

Differential use of vertical space by small mammals in the Monte Desert, Argentina

Space use in deserts usually has been considered only along the horizontal dimension; however, vertical structure could be an important variable for habitat segregation among small mammal species. Our study assessed the use of vertical space by small mammals of the Monte Desert by live-trapping animals at different heights. We recorded 1,336 captures of 4 rodent and 1 marsupial species in 27,600 trap nights. All 5 species were captured on the ground and in tree layers, but only the gray leaf-eared mouse (Graomys griseoflavus) and the desert mouse opossum (Thylamys pallidior) used vertical space appreciably. G. griseoflavus used the arboreal space independently of habitat, plant species, or branch diameter, whereas T. pallidior showed a more selective behavior, being present at greater heights and on large-diameter branches of Prosopis trees. All rodent species used lower more than higher parts of arboreal strata. They used vertical space more or only during the dry season when resource availability is low. Our study suggests that vertical structure offers greater opportunities to acquire resources when these are scarce and plays a role in the coexistence of small desert mammals.