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Agricultural expansion has had a detrimental effect on tropical forests and the animal communities that depend on them. Agroforestry systems, however, with their more complex tree and plant communities, have been shown to be important habitats for a range of globally threatened species, including nocturnal animals. Here, we present novel data on the encounter rates of seven species of nocturnal mammals in relation to agroforestry systems within four national parks and associated plantations in Bangladesh to examine if encounter rates were influenced by the human population density, presence of plantations, and human access as represented by a Human Influence Index of anthropogenic disturbance. We walked 70.3 km of transects with only semi-natural forest, 26.9 km of transects with semi-natural forest and gardens, and 21.7 km of transects with semi-natural forest and monocultures over 55 nights from 2017–2019. Of the seven species of nocturnal mammals we detected, all were present in Satachari National Park, whereas six occurred in Lawachara National Park, Rajkandi Forest Range, and Rema-Kalenga Wildlife Sanctuary. Within these national parks, three species (Bengal slow loris, large Indian civet, particolored flying squirrel) were more frequently recorded in areas with human disturbance, especially agroforestry plantations. With declining forest cover in Bangladesh, we highlight here the potential of agroforestry systems as emerging important habitats for these species. We encourage long-term studies of these lesser-studied taxa to understand fully the capacity of agroforestry systems in order to support their long-term conservation. [ABSTRACT FROM AUTHOR]

An individual of Pempheris rhomboidea species was detected in a cage where sea bream was grown in the Mersin Dana Island region. P. rhomboidea is a species of the Pempheridae family distributed in the Indo-Pacific and West Atlantic and is a nocturnal species that inhabit coral reefs and rocky waters. It is known that different wild fish species enter into the aquaculture fish cages where marine fish are grown and grow together with the aquaculture species. There is no previous record of this species obtained from aquaculture cages. The total length and weight of the individual in the cage were 12.6 cm and 23.938 g. Considering the mesh size of the cage, it is estimated that this individual entered the cage in the juvenile period. At the end of the 11-month aquaculture period, it was determined that the individual reached a length close to the maximum length that the species can reach in its natural habitat. It was determined that some morphometric characteristics of the individuals harvested from the cage were similar to individuals caught in nature. The ability of the nocturnal species to grow in aquaculture cages indicates strong adaptability. Other wild species harvested from the cage at the same time were Oblada melanura, Scomber japonicus, Liza ramada, Diplodus vulgaris, Alosa fallax nilotica, Siganus rivulatus, Trachurus mediterranus, Lichia amia, Argyrosomus regius, Spicara smaris, Coryphaena hippurus. The proportional increase of wild species in aquaculture fish cages may cause economic losses for the companies in the future. [ABSTRACT FROM AUTHOR]

Elusive species often use latrines which also serves as communication and information hubs. Thus, studying behavior at latrines may provide critical insights into the species' ecology and behavior. While it is established that musk deer use latrines for defecating, very little is known about the endangered Himalayan musk deer (Moschus leucogaster) and their latrines. We examined musk deer behavior from the various video clips lasting 238 min altogether, captured at latrine sites during both breeding and non‐breeding seasons in the Annapurna Conservation Area of Nepal. A total of 428 visits by musk deer and 479 behavioral events by them were captured. We constructed an ethogram to describe musk deer behavior and compared behavior across individuals and sex using parametric and non‐parametric tests. We found that musk deer are crepuscular and nocturnal animals. Both male and female musk deer repeatedly and independently visited shared latrine sites as well as exclusively used latrine sites. The proportion of male musk deer visited latrine sites were significantly higher than that of female musk deer. Hence, male musk deer were found more active (>2 times) than females during both seasons. The most frequently observed behavioral activities at the latrine sites were defecating, sniffing and browsing, followed by scrapping and covering, and ignoring the latrine sites. The defecating and sniffing activity were performed throughout breeding and non‐breeding seasons to establish communication among peers and to claim territory. Based on the behaviors observed at the latrine sites, we can presume that Himalayan musk deer likely use latrines to convey various messages, including personality, maturity, sexual status, and territory marking among conspecifics. These findings of this study can be used for the conservation of musk deer in its natural habitat and replicated in captivity to enhance breeding performance that improves long‐term conservation prospects for this species. [ABSTRACT FROM AUTHOR]

There is a lack of studies designed to detect the most important areas for bat conservation. In this context, areas of high bat activity have been rarely considered in the delimitation of protected areas for bats, which are generally focused on the protection of roosting sites. This has been due to the difficulties of sampling the distribution of these nocturnal animals when moving at night. This methodological constraint has been overcome by the development of bioacoustic sampling, which allows mapping the occurrence of active bats over large areas. In this study, we use bat detectors to sample the distribution of bat activity in central Spain. This region is under the environmental effects of a mountain range (Guadarrama Mountains) and the urban encroachment of the city of Madrid. The occurrences provided by the detectors were used to produce species distribution models of which the resulting layers were arranged to detect the most suitable areas for bat richness and rarity indices. We performed a gap analysis to explore whether the areas most commonly used by active bats are covered by the current network of protected areas. The results showed that the best areas of high bat activity are located at the piedmont of the mountains and that most of these areas overlap with the existing network of protected areas. The best areas for bats excluded the most urbanized areas and within a similar urban gradient, protected areas tended to be located within the best sites for conservation. These results suggest that bats currently benefit from a network of protected areas initially aimed to protect birds and habitats (Natura 2000). In addition, monitoring areas of high bat activity could complement roosting site protection in the conservation of bat assemblages. [ABSTRACT FROM AUTHOR]

We developed a sound discrimination device to identify and localize the species of nocturnal animals in their natural habitat. The sound discrimination device is equipped with a microphone, a light-emitting diode, and a band-pass filter. By tuning the center frequency of the filter to include a dominant frequency of the calls of a focal species, we enable the device to be illuminated only when detecting the calls of the focal species. In experiments in a laboratory room, we tuned the sound discrimination devices to detect the calls of Hyla japonica or Rhacophorus schlegelii and broadcast the frog calls from loudspeakers. By analyzing the illumination pattern of the devices, we successfully identified and localized the two kinds of sound sources. Next, we placed the sound discrimination devices in a field site where actual male frogs (H. japonica and R. schlegelii) produced sounds. The analysis of the illumination pattern demonstrates the efficacy of the developed devices in a natural environment and also enables us to extract pairs of male frogs that significantly overlapped or alternated their calls. [ABSTRACT FROM AUTHOR]

Increasing light emissions caused by human activities have been recognized as a major threat for nocturnal animals. In Switzerland, the European Nightjar is a rare bird, decreasing in numbers since the 1970s, and is therefore highly threatened. The last breeding population occurs in the canton Valais. Initial expert-based conservation measures on formerly inhabited breeding sites were successful until 2000, however recent additional measures have failed. Nightjars are highly sensitive to light due to their special retina adapted to living in semi-darkness. We hypothesized that food availability, mainly moths, is not a critical limiting factor, but that artificial light emissions prevent successful foraging as well as recolonizing revitalised breeding habitats of the nightjar. To test this hypothesis, we used light trapping data of moths from the last 30 years to evaluate food availability and compared light emission on abandoned versus still-occupied breeding sites. Abundance of larger moths did not change significantly over the last 30 years, and smaller moths even increased in abandoned as well as in still-occupied nightjar habitats. However, light emission was two to five times higher in abandoned compared to still-occupied sites. These results suggest that increasing light emission during recent decades has exceeded tolerable levels for this highly specialized night bird. Authorities of the canton Valais should therefore order a reduction in light emission near nightjar habitats by replacing bulbs currently in use with customized LED or broad-spectrum lamps low in white and blue light, and assign remaining nightjar habitats as areas of complete nocturnal darkness, thereby also protecting other threatened nocturnal animals, including moths. [ABSTRACT FROM AUTHOR]

Although it is well recognized that insects' habitat use and requirements may change during the season, very little attention has been devoted to diel habitat changes in most insects. In this study, we compared habitat utilization patterns of Sympetrum depressiusculum (Selys, 1841) adult dragonflies between daytime activities and nocturnal roosting. During daytime, we captured and marked adult individuals with fluorescent paint in different habitats. At night, we searched, using UV light, for marked individuals that remained on the habitats. We found that habitat selection for daytime activities and that for nocturnal roosting differed significantly. Adults clearly avoided ponds and their immediate surroundings for nocturnal roosting, whereas this habitat type was frequently utilized for daytime activities. We suggest that nocturnal avoidance of the riparian area is associated with lower temperatures, which adversely affect thermoregulation, and that selection of specific habitats for nocturnal roosting is closely associated with vegetation structure providing stability during windy nights and serving as a suitable shelter. Such habitat properties are found especially on fallow land, a habitat type whose representation in agricultural areas has been gradually decreasing in recent decades. [ABSTRACT FROM AUTHOR]

Silviculture used to alter forest structure and thereby enhance wildlife habitat has been advocated for bottomland hardwood forest management on public conservation lands in the Mississippi Alluvial Valley. Although some songbirds respond positively to these management actions to attain desired forest conditions for wildlife, the response of other species, is largely unknown. Nocturnal insects are a primary prey base for bats, thereby influencing trophic interactions within hardwood forests. To better understand how silviculture influences insect availability for bats, we conducted vegetation surveys and sampled insect biomass within silviculturally treated bottomland hardwood forest stands. We used passive blacklight traps to capture nocturnal flying insects in 64 treated and 64 untreated reference stands, located on 15 public conservation areas in Arkansas, Louisiana, and Mississippi. Dead wood and silvicultural treatments were positively associated with greater biomass of macro-Lepidoptera, macro-Coleoptera, and all insect taxa combined. Biomass of micro-Lepidoptera was negatively associated with silvicultural treatment but comprised only a small proportion of total biomass. Understanding the response of nocturnal insects to wildlife-forestry silviculture provides insight for prescribed silvicultural management affecting bat species. [ABSTRACT FROM AUTHOR]

Animals are adapted to a range of activity patterns, from diurnal to nocturnal. Under normal conditions, the 24-hour rhythm is entrained by changes in light intensity during twilight, i.e. the light and dark cycle. Many rodent species exhibit predator avoidance by adjusting their activity in relation to space or time, which isweighed against the need for food. Hence, an individual's foraging activity consists of a compromise between foraging and predation risk, in addition to competition. Our study species, the Eurasian red squirrel, is diurnal and utilises dense forest habitats. In the present study, we used non-invasive camera traps to model diel activity during the winter months in 2014-2015 (December to February 24-hour day). We found that the Eurasian red squirrels exhibited a strictly diurnal feeding activity pattern and the shape of the modelled activity curve was unimodal and concentrated in the daylight hours, starting at sunrise and peaking in the morning. [ABSTRACT FROM AUTHOR]

Estimates of biodiversity, population size, population density and habitat use have important implications for management of both species and habitats, yet are based on census data that can be extremely difficult to collect. Traditional assessment techniques are often limited by time and money and by the difficulties of working in certain habitats, and species become more difficult to find as population size decreases. Particular difficulties arise when studying elusive species with cryptic behaviours. Here, we show how geographic profiling ( GP) - a statistical tool originally developed in criminology to prioritize large lists of suspects in cases of serial crime - can be used to address these problems. We ask whether GP can be used to locate sleeping sites of spectral tarsiers T arsius tarsier in Sulawesi, Southeast Asia, using as input the positions at which tarsier vocalizations were recorded in the field. This novel application of GP is potentially of value as tarsiers are cryptic and nocturnal and can easily be overlooked in habitat assessments (e.g. in dense rainforest). Our results show that GP provides a useful tool for locating sleeping sites of this species, and indeed analysis of a preliminary dataset during field work strongly suggested the presence of a sleeping tree at a previously unknown location; two sleeping trees were subsequently found within 5 m of the predicted site. We believe that GP can be successfully applied to locating the nests, dens or roosts of elusive animals such as tarsiers, potentially improving estimates of population size with important implications for management of both species and habitats. [ABSTRACT FROM AUTHOR]

Local habitat structure and the environment in which it occurs are some of the key components in the development of fish communities. In this case study we examined a snapshot of their relative role following relocation of four artificial reefs (ARs) from a coral reef environment to a sandy area with adjacent sea grass beds. Monitoring the fish communities on ARs and in the surrounding areas revealed that in their new locations, the ARs contained greater fish richness and abundance, with more diurnal than nocturnal fish, but their feeding guilds were similar to those of fish in the reef location. A multivariate analysis showed that the ARs had distinctly different fish assemblage from those of their surroundings regardless of their location. Nonetheless, we identified an effect of the surroundings on AR fish community assemblage. We propose that on a meso- scale, fish community structure is primarily dependent on the properties of the AR rather than on those of the surrounding environment. [ABSTRACT FROM AUTHOR]

Upon leaving their natal area, dispersers are confronted with unknown terrains. Species-specific perceptual ranges (i.e. the maximum distance from which an individual can perceive landscape features) play a crucial role in spatial movement decisions during such wanderings. In nocturnal animals that rely on vision, perceptual range is dramatically enhanced during moonlight, compared to moonless conditions. This increase of the perceptual range is an overlooked element that may be responsible for the successful crossing of unfamiliar areas during dispersal. The information gathered from 143 radio-tagged eagle owl Bubo bubo juveniles in Spain, Finland and Switzerland shows that, although the decision to initiate dispersal is mainly an endogenous phenomenon determined by the attainment of a given age (∼6 months), dispersers leave their birthplace primarily under the best light conditions at night, i.e. when most of the lunar disc is illuminated. This sheds new light into the mechanisms that may trigger dispersal from parental territory. [ABSTRACT FROM AUTHOR]

Tampolo forest, in the north east of Madagascar, is a protected area of littoral forest, managed by ESSA- Forêts of the University of Antananarivo. Five species of nocturnal lemur are thought to be present in the forest; the aye-aye (Daubentonia madagascariensis), brown mouse lemur (Microcebus rufus), greater dwarf lemur (Cheirogaleus major), weasel sportive lemur (Lepilemur mustelinus) and eastern woolly lemur (Avahi laniger). However, currently there is a paucity of data on the density and distribution of these species. We used 20 line transects (0.5km in length) and distance sampling techniques to establish population sizes of lemur species and analysed our results using the software DISTANCE 6.0. The characteristics of lemur-used trees were catalogued during day surveys and compared to those of randomly selected trees to determine which characteristics were ecologically important to lemur species. Results indicate that the estimated population size of A. laniger is 150 individuals/km² (95% confidence interval: 84-267) and of M. rufus is 323 individuals/km² (95% confidence interval: 199-523). Only 3 individuals of C. major were observed and no individuals of D. madagascariensis or L. mustelinus were detected during line transects. This suggests low population sizes or potential difficulty in detecting these species, especially D. madagascariensis, which is at low natural densities throughout Madagascar and, given human persecution, has a high tendency for flight in the presence of humans. The average diameter at breast height (DBH) and height of trees used by A. laniger and the average height of trees used by M. rufus were significantly different to randomly selected trees. This suggests that particular trees may be of higher ecological importance to these lemur species than others, which enhances problems caused by deforestation. Our results suggest that the phenology of the trees used by both of these species was not a significant factor, though exploration into previous research suggest that our data may have been biased by seasonality. Further research on feeding ecology would be necessary to determine whether this is an important factor concerning lemur abundance in Tampolo Forest. Repetitions of our study over years to come will also serve to monitor long-term population trends in the region. [ABSTRACT FROM AUTHOR]

The article discusses a study which explored the distribution of the Kit Fox in the Great Basin Desert of southeastern Oregon. Because of its small physical size, nocturnal behavior and low population densities, the Oregon Conservation Strategy listed the Kit Fox as a strategy species. A total of 266 camera-nights were accumulated by the study, confirming the presence of the Kit Fox in the desert.

Abstract: Studies of the daily activity patterns of Octopus vulgaris have shown varying activity in different habitats. This might stem from the octopus' ability to respond to influences such as predation pressure by adjusting its activity pattern. To test the hypothesis that a predatory threat could alter activity cycles, six octopuses were each held in a partitioned tank with a potential predator for a week. After we had determined the circadian activity of each undisturbed subject for two days, a nocturnal (moray eel, Muraena helena) and a diurnal fish (triggerfish, Balistes carolinensis) were alternately introduced into the second compartment of the tank for seven days. Each of these periods was then followed by a four-day period without eel or triggerfish. During the experiment, subjects had visual and chemical access but no physical contact. Octopuses showed an increase in activity in the presence of both species, but this increase was only significantly negatively correlated with the activity of the triggerfish. Attacks on the barrier by the octopus and the triggerfish decreased throughout the week, but this was not true for the octopus and the moray eel. We concluded that O. vulgaris can use temporal spacing of activity to respond to potential predators. This ability might be responsible for conflicting reports of activity patterns of O. vulgaris. [Copyright &y& Elsevier]

Across West and Central Africa, duikers are important for trade and consumption; their populations are expected to become depleted. Reliable data on their status are scanty in Nigeria. We assessed duiker populations in the Oban Sector of Cross River National Park through diurnal and nocturnal surveys along 32 transects of 2 km each. After 508-km survey effort, only Ogilby's duiker ( Cephalophus ogilbyi) and blue duiker ( Philantomba monticola) were recorded. Using habitat as a covariate in modelling detection probability in DISTANCE 6.0, we estimated densities for the blue duiker ranging from 15.5 (95% CI: 7.8-30.9) in the core, 5.8 (CI: 2.6-12.9) in the buffer and 0.9 (CI: 0.09-10.1) km² in farm fallow to no duikers in the plantation. For Ogilby's duiker, densities ranged from 1.6 (95% CI: 0.7-3.7) km² in the core, 2.0 (CI: 0.8-5.1) in buffer to no duikers in farm fallow and plantation. The apparent absence of yellow-backed and Bay duikers may indicate local depletion. We call on all stakeholders to rise up to the challenge of rescuing this biological hotspot in Nigeria from further degradation and species loss through improved funding for well-equipped field staff and institutionalized community wildlife management. [ABSTRACT FROM AUTHOR]

We studied the population and feeding ecology of the kelp crab Taliepus marginatus in subtidal kelp forests dominated by either of two morphologically different kelp species ( Macrocystis pyrifera or Lessonia trabeculata) in northern Chile. The sizes and abundances of T. marginatus differed between the two kelp habitats. Kelp crabs were more abundant in the M. pyrifera forest than in the L. trabeculata forest. Size-frequency distributions showed that juvenile and immature crabs were more common in the M. pyrifera forest than in the L. trabeculata forest, where reproductive adults predominated. The smaller crabs in the M. pyrifera habitat also consumed a higher proportion of kelp tissues than the larger crabs in the L. trabeculata habitat, which had a higher proportion of animal food in their diet. In both kelp forests, individuals of T. marginatus showed a similar pattern of nocturnal feeding over a 24-h period, consuming more food at night than during the day. The more complex and dense forests of M. pyrifera appear to present better nursery habitats for juvenile kelp crabs than the more open and less dense forests dominated by L. trabeculata. These results suggest that the role of the two kelp habitats for T. marginatus varies during the life cycle of the kelp crabs, with M. pyrifera tending to have nursery function and L. trabeculata being more suitable as a reproductive habitat. [ABSTRACT FROM AUTHOR]

Abstract: We investigated activity patterns and habitat use of 34 radio-tracked mountain hares (Lepus timidus) in the Italian Alps. We first showed that hares were nocturnal and that activity patterns changed seasonally in parallel with circadian rhythms. We predicted that day home ranges will include suitable resting (shelter) habitats, and night home ranges will primarily include suitable foraging habitats. A hare''s night-range was larger than its day-range. On average, night and day ranges overlapped by 36%, suggesting that selective pressures affecting space use were, at least partly, different at night than day. Dwarf mountain-pine was the most preferred habitat in all seasons and was selected both for active behaviour (night) and resting (day) and hares avoided the most open habitats. Exploring the effects of season, time of day (day vs. night) and site, we found that habitat use by mountain hares did not differ between seasons or between the active (night) and resting (day) period of circadian cycle. Also, we found no effects of differences in landscape structure (habitat patchiness and heterogeneity) on the patterns of habitat selection. Hares always preferred the dense, forested habitats, which seemed to provide food resources as well as shelter from predators throughout the year. [Copyright &y& Elsevier]

Although variation in the color of light in terrestrial diurnal and twilight environments has been well documented, relatively little work has examined the color of light in nocturnal habitats. Understanding the range and sources of variation in nocturnal light environments has important implications for nocturnal vision, particularly following recent discoveries of nocturnal color vision. In this study, we measured nocturnal irradiance in a dry forest/woodland and a rainforest in Madagascar over 34 nights. We found that a simple linear model including the additive effects of lunar altitude, lunar phase and canopy openness successfully predicted total Irradiance flux measurements across 242 clear sky measurements (r=0.85, P<0.0001). However, the relationship between these variables and spectral irradiance was more complex, as interactions between lunar altitude, lunar phase and canopy openness were also important predictors of spectral variation. Further, in contrast to diurnal conditions, nocturnal forests and woodlands share a yellow-green-dominant light environment with peak flux at 560 nm. To explore how nocturnal light environments influence nocturnal vision, we compared photoreceptor spectral tuning, habitat preference and diet in 32 nocturnal mammals. In many species, long-wavelength-sensltive cone spectral sensitivity matched the peak flux present in nocturnal forests and woodlands, suggesting a possible adaptation to maximize photon absorption at night. Further, controlling for phylogeny, we found that fruit/flower consumption significantly predicted short-wavelength-sensltive cone spectral tuning in nocturnal mammals (P=0.002). These results suggest that variation in nocturnal light environments and species ecology together influence cone spectral tuning and color vision in nocturnal mammals. [ABSTRACT FROM AUTHOR]

The diel activity rhythm of red-spotted grouper Epinephelus akaara was studied both in captivity and in the wild. Behavior of solitary grouper (58 to 397 mm in total length) in a tank was video recorded using infrared illuminators under 11L/10D and two 1.5-h twilight transition periods, and was compared to that of banded wrasse Halichoeres poecilopterus, a typical diurnal fish. Underwater observations using SCUBA were also conducted in their natural habitat to reveal the behavioral activity together with a visual census of adjacent fish and crustacean assemblages. Red-spotted grouper showed a strong nocturnal activity in a tank regardless of body size as opposed to the strongly diurnal banded wrasse. Activity of groupers in natural waters was high at dawn and dusk, low at noon, and only a few individuals were observed at night. Visual census in the habitat revealed that fish abundance and species richness was highest at noon, lowest at night, and intermediate at dawn and dusk. The opposite trend was found in crustacean assemblages. Absence of groupers at night may reflect their nocturnal feeding migration away from the study area. Alternatively, the crepuscular activity of groupers in the wild is suggested to be an adaptation to feed on small fishes that shift between daytime activity and nighttime rest and/or on nocturnal crustaceans that show the opposite activity pattern. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the diversity and relative abundance of fish species in six coastal habitats during the day and at night. Habitats included seagrass beds, Ecklonia macroalgal beds, other macrophytes, deep reef, rhodolith beds and sand. Surveys were conducted using baited remote underwater stereo-video systems, which at night were equipped with either white or red lights. Three research questions were examined; 1) do fish assemblages sampled during the day differ to those sampled at night across six inshore and near shore marine habitats? 2) Are patterns of habitat associations displayed by diurnal fishes maintained at night? 3) Do stereo-BRUVs sample different fish assemblages when equipped with red versus white lights? Diurnal surveys sampled significantly greater species richness (66% greater) and numbers of individuals (92% more than red lights, 82% than white lights) than nocturnal surveys. Diurnal surveys also showed greater discrimination in the fish assemblages between the six habitats with replicate samples from a habitat clustered together. This clustering of replicate samples was reduced at night where a number of species of fish were seen in multiple habitats. Thirty-one percent of the species viewed at night were seen on multiple habitats, but only a single habitat during the day. Compared to red lights, white lights surveyed a greater number of individuals and species in rhodolith beds (94% more individuals and 63% more species) and over sand (94% more individuals, 83% more species). This was likely due to an attraction of fish to bait fish accumulating near the white light source, but not in the red light source. However, surveys of fish assemblages at night were deemed most effective when red lights were used, because this lighting type had an improved ability to statistically distinguish fish assemblages across the habitats surveyed. By conducting nocturnal survey studies researchers may obtain a more holistic understanding of habitat use by fish species and account for this usage in biodiversity and fisheries management plans. [Copyright &y& Elsevier]

Abstract: We investigated the wing morphology and foraging distributions of sympatric Rhinolophus and Hipposideros species by acoustic sampling, measuring wing parameters, and observing bats in different settings of tropical East Asian forests, to evaluate their flexibility in habitat use and edge sensitivity. R. formosae and H. terasensis were more abundant at edges/in open habitats and shared the highest overlap, with R. formosae displaying the greatest breadth in habitat use, whereas R. monoceros had a higher abundance and feeding efficiency in forest interiors with a continuous canopy. H. terasensis was significantly larger and had higher wing loading and aspect ratio than R. formosae and R. monoceros, while R. formosae had higher wing loading but a lower aspect ratio than the smaller-sized R. monoceros. Shrubs and herbs were higher at sites where bats were captured than at those without bat captures, and R. monoceros and R. formosae were associated with greater canopy and ground coverage, respectively. R. monoceros always foraged while flying at lower heights close to the herb/shrub layers, while H. terasensis and R. formosae used perching to different extents, with R. formosae preferably using fly-catching techniques and appearing farther from the path in open forests rather than in forest interiors. Our results indicate that differences in wing parameters account for the different degrees of flexibility in habitat use, yet the deviations of call frequency from the expected values in R. formosae and H. terasensis suggest additional adaptations accounting for their flexibility in exploring habitats. [Copyright &y& Elsevier]

We present a novel method for imaging acoustic communication between nocturnal animals. Investigating the spatio-temporal calling behavior of nocturnal animals, e.g., frogs and crickets, has been difficult because of the need to distinguish many animals' calls in noisy environments without being able to see them. Our method visualizes the spatial and temporal dynamics using dozens of sound-to-light conversion devices (called 'Firefly') and an off-the-shelf video camera. The Firefly, which consists of a microphone and a light emitting diode, emits light when it captures nearby sound. Deploying dozens of Fireflies in a target area, we record calls of multiple individuals through the video camera. We conduct two experiments, one indoors and the other in the field, using Japanese tree frogs ( Hyla japonica). The indoor experiment demonstrates that our method correctly visualizes Japanese tree frogs' calling behavior. It has confirmed the known behavior; two frogs call synchronously or in anti-phase synchronization. The field experiment (in a rice paddy where Japanese tree frogs live) also visualizes the same calling behavior to confirm anti-phase synchronization in the field. Experimental results confirm that our method can visualize the calling behavior of nocturnal animals in their natural habitat. [ABSTRACT FROM AUTHOR]

Abstract: The eastern spadefoot toad (Scaphiopus holbrookii) is listed as endangered in Connecticut, having only one viable population in the state. Efforts to investigate their distribution in Connecticut are frustrated by their rarity, as well as their nocturnal and fossorial habits. The purpose of this study was to develop a geographic information systems (GIS) model to identify eastern spadefoot toad habitat in eastern Connecticut. Known eastern spadefoot toad sites in Connecticut, Massachusetts, and Rhode Island were used to establish the model’s selection criteria (i.e., substrate and elevation). Drainage class, texture class and soil deposit type within 250 meters of each site were summarized by acreage to reveal the predominant characteristics of the substrate. Digital elevation models (DEMs) were used to calculate relative elevation, expressing the absolute elevation as a percentage of the range in the surrounding landscape. Applying the selection criteria in eastern Connecticut produced a GIS shapefile of potential eastern spadefoot toad habitat. The results of verification analyses suggest that the eastern spadefoot toad habitat model (ESTHM) is a promising tool for identifying areas of eastern spadefoot toad habitat. [Copyright &y& Elsevier]

The Llanos de Ojuelos in Mexico's Central High Plateau supports unique Opuntia scrublands and the southernmost Chihuahuan grasslands. Although human activities have modified strongly its landscape and impacted its biodiversity at an unknown scale, such impacts are poorly known. We aimed at understanding how nocturnal rodent species distributed across the landscape and formed assemblages and on the role and integration of the different habitats at the landscape level. The study was carried out at 43 sites in a study area of approximately 3350 km in the Llanos de Ojuelos. During the Spring of 2008, we surveyed nocturnal rodents, through live-trapping. We redefined habitat classes based on log-linear multinomial regressions of rodent captures. Species rarefaction curves and true alpha, beta and gamma diversities were calculated for the different habitat classes. A map of the different habitats was constructed based on Landsat imagery. We captured 458 individuals of 20 rodent species. Multinomial regressions caused the merger of 11 a priori defined habitat classes into 7. Leguminous scrub and mixed nopaleras, both secondary habitats, had the highest alpha and gamma diversity values. Closed arboreal nopaleras and grasslands had the highest within-habitat variability ( D) and the lowest area coverage. Within-habitat D was larger than landscape D, because of the great overlap in rodent assemblage composition between the habitats. There are no 'typical' rodent assemblages per habitat class, but they are organized loosely and have fuzzy borders. Rodent community organization was highly species-centred. At the landscape level, secondary habitats have a profound effect on rodent diversity and should be included in management schemes for biological conservation. The most endangered habitats seem to be the closed arboreal nopaleras and grasslands. Any conservation efforts must consider their conservation and an increase in the size of remaining patches. [ABSTRACT FROM AUTHOR]

Nonhuman primates may defend crucial resources using acoustic or chemical signals. When essential resources are limited, ownership display for a resource may be enhanced. Defending resources may depend on population density and habitat characteristics. Using the Milne Edwards' sportive lemurs ( Lepilemur edwardsi) and weasel sportive lemurs ( L. mustelinus) as models, we tested whether two cryptic nocturnal lemur species differing in population density and habitat show differences in their vocal and chemical communication for signaling ownership of resources. L. edwardsi inhabits a western dry deciduous forest in a high-density population, whereas L. mustelinus is found in an eastern rainforest in low density. We followed ten L. edwardsi (six males and four females) and nine L. mustelinus (four males and five females) for 215 hr during the early evening (06:00-10:00 p.m.) and the early morning (02:00-05:00 a.m.) and recorded their behavior using focal animal sampling. We found that both species differed in their vocal and chemical communication. L. edwardsi was highly vocal and displayed loud calling in the mornings and evenings while feeding or in the vicinity of resting places. In contrast, L. mustelinus never vocalized during observations, but displayed tree-gouging behavior that was never observed in L. edwardsi. Tree gouging occurred more often during early evening sessions than early morning sessions. Subjects gouged trees after leaving their sleeping hole and before moving around. We suggest that, in weasel sportive lemurs, non-nutritive tree gouging is used as a scent-marking behavior in order to display ownership of sleeping sites. Altogether, our findings provide first empirical evidence on the evolution of different communication systems in two cryptic nocturnal primate species contrasting in habitat quality and population density. Further investigations are needed to provide more insight into the underlying mechanisms. Am. J. Primatol. 72:1062-1072, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Noise generated by a reef community provides a valuable orientation cue for reef fish; both for larvae as they recruit to reefs, and for adults and juveniles during nocturnal movements. However, the nature of the information conveyed in reef noise is as yet unknown. In this study, the characteristics of daytime acoustic recordings from patch and fringing reefs in the Las Perlas Archipelago, Pacific Panama were compared. Recordings of ambient noise made during the day showed coral reef communities produced acoustic profiles that varied spatially across the Archipelago. At eleven reef sites in the north of the Archipelago, data were also collected on fish and benthic communities using standard visual survey techniques. These data, along with existing survey data from 40 reef sites, were compared with short-term (2 minute) acoustic profiles to explore associations between point sampled acoustic and census data. Using a correlation matrix, the best predictors of acoustic characteristics were identified from a range of factors, including fish density and biomass, coral and fish diversity, coral and algal cover, reef depth and sea state. Multiple regression GLMs highlighted the importance of fish density and diversity on noise below 1kHz, and coral and benthic diversity on noise above 1kHz. A positive correlation was also found between coral cover and daytime noise intensity across the entire Archipelago, suggesting potential in the future development of passive acoustics as a method for rapid ecological assessment or for long-term monitoring of reefs. These findings demonstrate the richness of information available to reef fishes, and make the case for further studies that explore the relationships between habitat and community characteristics with temporal and spatial variation in reef noise. [ABSTRACT FROM AUTHOR]

Mehner T, Busch S, Helland IP, Emmrich M, Freyhof J. Temperature-related nocturnal vertical segregation of coexisting coregonids. Ecology of Freshwater Fish 2010: 19: 408–419. © 2010 John Wiley & Sons A/S Habitat choice of fish may be influenced by many different ecological factors, e.g., predation risk, feeding opportunity, or temperature and oxygen availability. However, because most of the fish prey and their predators rely on vision for feeding, the predator avoidance and feeding opportunity hypotheses may fail to predict distribution of fish at complete darkness. Here, we accumulated patterns of nocturnal vertical distribution of two coexisting coregonid populations in Lake Stechlin from 13 samplings over 4 years, conducted by hydroacoustics and simultaneous midwater trawling. We calculated population depths, dispersion, illumination strengths and vertical temperature gradients for all sampling dates. Illumination strengths at fish population depths were far below the critical levels for feeding by vision, suggesting that predator avoidance or feeding opportunity did not trigger the depth distribution at night. In contrast, nocturnal population depths and dispersion of vendace Coregonus albula were significantly associated with the seasonally changing vertical temperature gradient in Lake Stechlin, whereas night-time distribution of the coexisting Fontane cisco Coregonus fontanae was almost unaffected by temperature. Vendace occurred just below the thermocline in isothermal water layers of about 6.5–9 °C during stratification of Lake Stechlin, whereas Fontane cisco preferred 4–6 °C cold layers. These experienced temperatures roughly correspond to species-specific optimum metabolic temperatures determined in earlier experiments. We assume, therefore, that the temperature-related vertical segregation during non-feeding hours at darkness is linked with metabolic benefits, thus suggesting that bioenergetics efficiency contributes to ultimate causes of diel vertical migrations at least in vendace. [ABSTRACT FROM AUTHOR]

The pygmy rabbit (Brachylagus idahoensis) is a secretive, obligate sagebrush-steppe resident of the Intermountain West and is one of two rabbits in North America that digs its own burrows. Although the pygmy rabbit has a recorded home range of 0.21-67.9 ha in relatively high sagebrush cover (21%-36%), they spend much of their time within 30-100 m of a burrow system. Due to big sagebrush cover in preferred habitat and the secretive behavior of pygmy rabbits, it is often difficult to study this leporid through direct observation. We used remote cameras to document pygmy rabbit activity at burrow systems in south central Utah from 2006 to 2008. We analyzed photographs from remote cameras for daily and seasonal patterns of activity. Our results suggested that time of day and season were important influences on activity level, while year and site were less so. Pygmy rabbits were active during all time periods of the day, but the greatest activity occurred in the morning, except during winter. Numerous other species were recorded by remote cameras, including other leporids, birds, rodents, reptiles, and terrestrial predators. Remote cameras are a valuable tool in understanding pygmy rabbit behavior, in addition to confirming rabbit presence in areas of interest. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the activity patterns and habitat use of sympatric small carnivores in southern Taiwan. From March 1998 to February 2001, the activity patterns and habitat use of the carnivores were examined using camera-trapping. Elevation, slope, aspect and forest type are some of the macro- and micro-habitat variables that were measured at each camera-trapping site and used for analyses. The study found that some of the carnivores are nocturnal, including the Indian civet and masked palm civet. It also discovered the occurrence of segregation of temporal activity and habitat use among four sympatric carnivores.

The article presents a study which focuses on the aspects of the population ecology of the exotic amphipod, Talitroides topitotum, in an Atlantic forest area in Brazil. It discusses the ecological habitat of the terrestrial amphipods which live in forest litter and its interface with the soil or the habitats similar to those terrestrial isopods. It states that terrestrial amphipods, which are usually nocturnal animals, can reproduce up to two times during their life time with a brood of 3 or 4 eggs and an average of 10-month life span. It notes that throughout the study, 3,593 female T. topitotum were collected.

In the Drowned Cayes area of Belize, manatees (Trichechus manatus manatus) are commonly observed resting in depressions in the substrate, locally referred to as manatee resting holes. To understand why manatees prefer locations with resting holes, the physical and environmental attributes of the depressions were characterized and diurnal and nocturnal use by manatees at four resting hole sites were documented over two summers. Twelve resting hole sites were compared with 20 non-resting hole sites in the Drowned Cayes, using water depth, substrate type, vegetation, water velocity, salinity, and water temperature. Four resting holes were chosen for repeated diurnal and nocturnal observations, during which sea and weather conditions were recorded in addition to the presence/absence of manatees. Resting holes were significantly deeper and had slower surface water velocity than areas without resting holes. A total of 168 point scans were conducted over 55 d, resulting in 39 manatee sightings over two summers. There was a significant difference in the number of sightings between research years and between day and night scans. Given the large number of resting holes in the Drowned Cayes, many of which are in sheltered areas with slow currents, it is possible that manatees select these spots based on the tranquility of the water and environment. The combination of slow currents, protection from waves, low numbers of boats, and nearby seagrass beds would make these ideal resting areas. These findings have implications for the conservation of important manatee habitat. [ABSTRACT FROM AUTHOR]

Nocturnal mammals are poorly studied in Central Africa, a region experiencing dramatic increases in logging, roads, and hunting activity. In the rainforests of southern Gabon, we used spotlighting surveys to estimate abundances of nocturnal mammal species and guilds at varying distances from forest roads and between hunted and unhunted treatments (comparing a 130-km2 oil concession that was nearly free of hunting, with nearby areas outside the concession that had moderate hunting pressure). At each of 12 study sites that were evenly divided between hunted and unhunted areas, we established standardized 1-km transects along road verges and at 50, 300, and 600 m from the road. We then repeatedly surveyed mammals at each site during 2006. Hunting had few apparent effects on this assemblage. Nevertheless, the species richness and often the abundance of nocturnal primates, smaller ungulates, and carnivores were significantly depressed within approximately 30 m of roads. Scansorial rodents increased in abundance in hunted forests, possibly in response to habitat changes caused by logging or nearby swidden farming. In multiple-regression models many species and guilds were significantly influenced by forest-canopy and understory cover, both of which are altered by logging and by certain abiotic variables. In general, nocturnal species, many of which are arboreal or relatively small in size (<10 kg), were less strongly influenced by hunting and more strongly affected by human-induced changes in forest structure than were larger mammal species in our study area. [ABSTRACT FROM AUTHOR]

We used radio-telemetry to investigate the movement patterns of river blackfish [ Gadopsis marmoratus (Richardson)] in Armstrong Creek, south-eastern Australia between August and October 2005. Movements of 11 fish were monitored 2–3 times per week during daylight over 48 days and diel movements of six fish monitored hourly for three consecutive days and nights. Most river blackfish displayed little or no movement during the day and were confined to distinct positions in the stream. However, fish moved over significantly larger ranges and moved amongst mesohabitats at night, which would not have been detected using daylight tracking data only. River blackfish most often were located within pools, but they also commonly used riffle and run habitats. We also found that several fish used inundated riparian areas during a flood and two fish made rapid, large movements coinciding with the elevated flows. This study has revealed previously undocumented aspects of the movements and behaviour of river blackfish. The study has also shown the potential for different conclusions regarding the extent of movement by a species depending on the temporal scale and the timing of observations. [ABSTRACT FROM AUTHOR]

We report on aspects of the ecology and natural history of 2 species of armadillos commonly found in a cerrado remnant in southeastern Brazil--the naked-tailed armadillo (Cabassous unicinctus) and the 6-banded armadillo (Euphractus sexcinctus). Armadillos were captured in pitfall traps or by hand, double-marked, and the habitat (campo sujo, campo cerrado, and gallery forests), season, and time of capture were recorded. We also recorded the sex and age of all armadillos, and reproductive condition of females. Population densities were estimated as 0.27 and 0.14 individuals/ha for C. unicinctus and E. sexcinctus, respectively. E. sexcinctus did not preferentially use any of the habitats included in the study area, whereas C. unicinctus preferentially used habitats with a more complex vegetation structure, such as gallery forests. C. unicinctus was diurnal and E. sexcinctus was mainly nocturnal. Neither species changed its activity pattern with season, but C. unicinctus was more active in months with decreased abundance of arthropods--the main food resource consumed by this species. Both species of armadillos appeared to reproduce year-round. Differences in habitat use and daily activity between C. unicinctus and E. sexcinctus suggest spatial and temporal displacement between these species. [ABSTRACT FROM AUTHOR]

We examined the diurnal refuges occupied by the nocturnal squirrelfish, Holocentrus rufus, to describe refuges and the behavior associated with their use and to determine which, if any, refuge characteristics were selected. We tagged 21 H. rufus on two sites on a fringing reef in Barbados, West Indies, identified the refuges they used ( n = 57), measured ten characteristics of each refuge and the surrounding microhabitat, and monitored their refuge use for 4 weeks. To evaluate refuge selection, we measured the same characteristics on a comparable number of unused potential refuges ( n = 67) on the same reefs and used classification tree models to determine which characteristics separated used from unused refuges. Each fish used 1–9 refuges, which did not overlap among individuals and were defended against intrusion by conspecifics and some heterospecifics. Fish with more than one refuge frequently moved among them. There was strong site fidelity with no immigration of untagged fish or emigration of tagged fish on either reef during the study period and no additional refuges being occupied over the 4-week period. Refuges were primarily holes, open at one or two ends, which varied in size, distance from the reef edge, entrance orientation, and vertical relief at the entrance. Holes used as refuges differed significantly from unused holes mainly in characteristics related to the vertical position of their entrance, but the classification tree models differed for the two sites. This study provides the first detailed information on characteristics of daytime refuges used by a nocturnally active reef fish and the first evidence of selectivity of refuges. It suggests that the abundance and characteristics of holes on reefs could influence the density of H. rufus on natural reefs. [ABSTRACT FROM AUTHOR]

Daytime refuges are important to nocturnal rodents for protection from predators and environmental extremes. Because refuges of forest-dwelling rodents are often associated with woody debris, we examined refuge use by 37 radio-collared Peromyscus gossypinus (cotton mice) in experimental plots with different levels of woody debris. Treatment plots had six times (≈ 60 m³/ha) the volume of woody debris as control plots (≈ 10 m³/ha). Of 247 refuges, 159 were in rotting stumps (64%), 32 were ill root boles (13%), 19 were in brush piles (8%), and 16 were in logs (6%): 10 refuges could not be identified. Stumps were the most common refuge type in both treatments, but the distribution of refuge types was significantly different between treatment and control plots. Root boles and brush piles were used more on treatment plots than on control plots, and logs were used more on control plots than on treatment plots. Refuge type and vegetation cover were the best predictors of refuge use by cotton mice; root bole refuges and refuges with less vegetation cover received greater-than-expected use by mice. Abundant refuges, particularly root boles, may improve habitat quality for cotton mice in southeastern pine forests. [ABSTRACT FROM AUTHOR]

Ecological information on coastal fish distribution patterns and habitat use can be greatly improved by nocturnal samplings and observations. To this purpose, the structure of a Mediterranean fish assemblage inhabiting the shallow rocky littoral of Linosa Island (Sicily Strait, Italy) was examined by using visual census to detect possible diel variations in species composition and abundance. Day–night fish distribution patterns were investigated by multivariate and univariate analyses. Overall, 42 fish taxa belonging to 19 families were recorded: 35 during the day and 24 during the night. Seventeen species were common to both diurnal and nocturnal assemblages. Within the diurnal assemblage, Chromis chromis was the most represented species (37.2%), followed by Thalassoma pavo (23.2%) and Sparisoma cretense (10.8%). Within the nocturnal assemblage, the most abundant taxon was Atherina spp. (33.9%), followed by Apogon imberbis (26.4%) and Boops boops (11.5%). Our results indicated wide variation in the abundance and species composition during the day and during the night. Multi Dimensional Scaling plot showed a clear-cut separation between the two assemblages and analysis of similarities found significant differences as well. SIMPER analysis revealed that ten species individually contributed by more than 2.5% to the dissimilarity between diurnal and nocturnal assemblages, T. pavo, C. chromis and S. cretense being the first three species in order of decreasing percentage. ANOVA performed on species richness and fish abundance detected significant differences between diurnal and nocturnal assemblages, the latter showing far lower average values for both variables. [ABSTRACT FROM AUTHOR]

The microhabitat used by the garden dormouse Eliomys quercinus during its nocturnal activity was examined. Twenty-three variables describing habitat structure were measured at 100 trapping points. Logistic regression models were utilized to select the variables that discriminate between used and avoided trapping points and, in a series of pairwise contrasts, between trap sites used by different sexes, age classes and animals in different reproductive periods. Used sites were characterized by a higher (>40%) rock cover, a thicker shrub layer and a younger understory with trees of smaller trunk diameter. These variables describe areas with rockfalls from the upper slope, where trees were younger and smaller, the canopy closure reduced and the shrub layer more developed than in other parts of the forest. Dense shrubby vegetation provided protection from aerial predators and, in conjunction with rocks and stones, might have made hunting by birds and mammals more difficult. Garden dormice may also have been attracted by rocky areas acting as a heat source during the night. The selection of rocky areas was more important in the first months of the active period, when animals emerged from hibernation and started the mating season. At the end of summer, the animals used areas richer in herbs, where insects and other food resources were probably more abundant. [ABSTRACT FROM AUTHOR]

Shorebird roosts are often considered traditional, on the basis of predictable occupancy by large numbers of birds over long periods. However, fidelity of individuals to roosts at fine spatial and temporal scales, particularly at night, has rarely been described. We compared diurnal and nocturnal use of high-tide roosts by radiotagged Dunlin (Calidris alpina pacifica) wintering (November-March) at Humboldt Bay, California. Despite high fidelity to the study area, fidelity to particular roosts was relatively low and highly variable. At night, Dunlin used fewer roosts, were more faithful to primary roosts, and moved shorter distances between successive roosts than during the day. Day and night roosts differed in location, habitat, and distance from tidal flats. At night, Dunlin made greater use of pasture, and less use of islands and manmade structures. Day and night strategies of high-tide space use by Dunlin may be related to differences in food availability or predation danger. Our results illustrate that notions of tradition and site fidelity are scale-dependent and that knowledge of space use across the full range of environmental conditions is necessary for appropriate management of shorebird habitat. [ABSTRACT FROM AUTHOR]

Caribbean seagrass beds are important feeding habitats for so-called nocturnally active zoobenthivorous fish, but the extent to which these fishes use mangroves and seagrass beds as feeding habitats during daytime remains unclear. We hypothesised three feeding strategies: (1) fishes feed opportunistically in mangroves or seagrass beds throughout the day and feed predominantly in seagrass beds during night-time; (2) fishes start feeding in mangroves or seagrass beds during daytime just prior to nocturnal feeding in seagrass beds; (3) after nocturnal feeding in seagrass beds, fishes complete feeding in mangroves or seagrass beds during the morning. We studied the effect of habitat type, fish size, social mode and time of day on resting and feeding behaviour of large juvenile (5–10 cm) and sub-adult (10–15 cm) Haemulon flavolineatum in mangroves and seagrass beds during daytime. Sub-adults occurred in mangroves only, spent most time on resting, and showed rare opportunistic feeding events (concordant with strategy 1), regardless of their social mode (solitary or schooling). In contrast, large juveniles were present in both habitat types and solitary fishes mainly foraged, while schooling fishes mainly rested. Exceptions were small juveniles (±5 cm) in seagrass beds which foraged intensively while schooling. Large juveniles showed more feeding activity in seagrass beds than in mangroves. In both habitat types, they showed benthic feeding, whereas pelagic feeding was observed almost exclusively in the seagrass beds. In both habitat types, their feeding activity was highest during 8:00–10:30 hours (concordant with strategy 3), and for seagrass fishes, it was also high during 17:30–18:30 hours (concordant with strategy 2). The study shows that both mangroves and seagrass beds provide daytime feeding habitats for some life-stages of H. flavolineatum, which is generally considered a nocturnal feeder. [ABSTRACT FROM AUTHOR]

Octopus macropus and Octopus vulgaris have overlapping habitats and are exposed to similar temporal changes. Whereas the former species is described as nocturnal in the field, there are conflicting reports about the activity time of the latter one. To compare activity patterns, the authors tested both species in the laboratory. Octopuses were exposed to a light-dark cycle and held under constant dim light for 7 days each. 0. macropus showed nocturnal and light-cued activity. According to casual observations, O. vulgaris started out nocturnal but had switched to mostly diurnal when the experiment began. Individual variation of its activity was found. The different activity patterns of O. macropus and O. vulgaris might reflect their lifestyles, the latter species being more generalist. [ABSTRACT FROM AUTHOR]

Coppertail skinks ( Ctenotus taeniolatus) are medium-sized diurnal lizards that are widespread in eastern Australia. Field surveys on sandstone outcrops in the Sydney region showed that these animals use available rocks non-randomly: coppertails were found under large, sun-exposed rocks on deep soil. Choice trials in the laboratory documented selection of retreat sites that were warm, with substrate preferences shifting in a diel cycle. Lizards selected retreats with rock substrates during the day but with sandy substrates at night. Rocky retreats attain higher temperatures during daylight hours, but burrows in sand beneath rocks may provide greater protection against ingress by nocturnal predators. During fieldwork we rarely found lizards under rocks with either ants or centipedes, suggesting that coppertails may avoid these predatory invertebrates. Tongue-flick trials showed that the lizards could discriminate among common ant species based on chemosensory cues, but apparently could not detect centipede chemical cues. In experimental trials, the lizards did not avoid retreat sites scented by either ants or centipedes. Our data thus suggest that retreat-site selection in coppertails is driven by abiotic cues (rock size, sun exposure and substrate type) that may confer fitness benefits in terms of thermoregulation and predator avoidance, with biotic cues playing a less important role. [ABSTRACT FROM AUTHOR]

Abstract: The lagoon of Moorea Island was characterised by 12 distinct reef zones. Visual censuses allowed us to document the spatial distributions of recently settled juveniles vs adults of 17 nocturnal fish species among the 12 reef zones. Five distinct patterns in habitat use were found: an increase in the number of reef zones used during the adult stage (four species); a decrease in the number of reef zones adults used compared to recently settled juveniles (two species); the use of different reef zones (one species); the use of same reef zones but with relative densities different (one species); and no change in habitat use (nine species). Overall, this study is the first to explore the use of space by a broad range of nocturnal fish taxa to document the patterns and determinism of habitat shifts between juvenile and adult life stages. To cite this article: D. Lecchini, C. R. Biologies 329 (2006). [Copyright &y& Elsevier]

For many animals, selecting whether to forage during day or night is a critical fitness problem: at night, predation risks are lower but feeding is less efficient. Habitat selection is a closely related problem: the best location for nocturnal foraging could be too risky during daytime, and habitat that is safe and profitable in daytime may be unprofitable at night. We pose a theory that assumes animals select the combination of daytime and night activity (feeding vs. hiding), and habitat, that maximizes expected future fitness. Expected fitness is approximated as the predicted probability of surviving starvation and predation over a future time horizon, multiplied by a function representing the fitness benefits of growth. The theory's usefulness and generality were tested using pattern-oriented analysis of an individual-based model (IBM) of stream salmonids and the extensive literature on observed diel behavior patterns of these animals. Simulation experiments showed that the IBM reproduces eight diverse patterns observed in real populations. (1) Diel activity (whether foraging occurs during day and/or night) varies among a population's individuals, and from day to day for each individual. (2) Salmonids feed in shallower and slower water at night. (3) Individuals pack more tightly into the best habitat when feeding at night. (4) Salmonids feed relatively more at night if temperatures (and, therefore, metabolic demands) are low. (5) Daytime feeding is more common for life stages in which potential fitness increases more rapidly with growth. (6) Competition for feeding or hiding sites can shift foraging between day and night. (7) Daytime feeding is more common when food availability is low. (8) Diel activity patterns are affected by the availability of good habitat for feeding or hiding. We can explain many patterns of variation in diel foraging behavior without assuming that populations or individuals vary in how inherently nocturnal or diurnal they are. Instead, these patterns can emerge from the search by individuals for good trade- offs between growth and survival under different habitat and competitive conditions. [ABSTRACT FROM AUTHOR]

We studied temporal partitioning between two spiny mouse species that coexist in hot rocky deserts in the Middle East: nocturnal common spiny mice (Acomys cahirinus) and diurnally active golden spiny mice (A. russatus). Although A. russatus is diurnally active, it retains the physical activity and body temperature rhythms of nocturnal mammals. We studied the two species in four 1000-m2 enclosures at Ein Gedi, Israel: two experimental enclosures with A. russatus kept alone, and two controls with individuals of both species kept together. We monitored activity with Sherman traps and by studying foraging microhabitat use and efficiency using giving-up densities (GUDs) in food trays. The trays contained broken sunflower seeds mixed in local soil and placed in three micro-habitats: under boulders, between boulders, and in the open. Trapping revealed that, in the absence of A. cahirinus, the usually diurnal A. russatus was active both day and night. However, during the day A. russatus still foraged in significantly more patches and to significantly lower GUDs than during the night. Both species, but in particular A. russatus, preferred to forage in the boulder habitat. Spiny mice foraged in the same number of trays in the under- and between-boulder microhabitats, but to lower GUDs in the under-boulder microhabitat, both during the day (A. russatus) and during the night (both species). The nocturnal A. cahirinus exploited more patches with greater efficiency than did A. russatus either during the day or during the night. This result suggests that foraging trade-offs that give each species a competitive advantage along some portion of the resource axis cannot be a mechanism of nocturnal coexistence between the two species. Perhaps this is why A. russatus resorts to diurnal activity in this hot rocky desert and why the otherwise rare mechanism of temporal partitioning occurs br these species. [ABSTRACT FROM AUTHOR]

In the summer Atlantic salmon Salmo salar parr were predominantly active at night, while young-of-the-year were equally active during day and at night. These findings are consistent with the prediction that larger animals should be less willing to risk predation for a certain increase in size than smaller animals. [ABSTRACT FROM AUTHOR]

The article provides information on the habitat of the Brazilian Spotted Night Snake or Siphlophis longicaudatus. It says that S. longicaudatus is a type of snake known as nocturnal with habits that are described as semi-arboreal. According to the author, the need to focus more on the poor ecosystem in Brazil is emphasized by the observation that the snake inhabit forested habitats despite the presence of a vast open area in the Cerrado biome. Information on the highest and lowest temperature of S. longicaudatus as well as its diet are also discussed.