Different Times Of Night Research Articles

Bird–building collisions increase with weather conditions that favor nocturnal migration and with inclement and changing weather

AbstractCollisions with building windows are a top bird mortality source, but few studies have evaluated how bird–window collisions are influenced by weather. By monitoring collisions daily at 21 buildings in Minneapolis, Minnesota, over 4 migration seasons, we show that weather influences numbers of window collisions of nocturnal migrants in spring and fall, indicating that collisions may be forecastable based on weather conditions. Collisions increased with weather favoring migration, such as consecutive nights of south wind in spring and even short periods of north wind in fall. We also found evidence that spring and fall collisions increase with weather changes that impede migration, such as changes from fair conditions and tailwinds early in the night to headwinds near sunrise. Our study suggests complex weather effects never before considered in the context of bird collisions, including possible time lag effects of conditions 2–3 nights before collisions occur, effects of multi-day sequences of conditions, and interactions between conditions at different times of night. More research is needed to determine if the accuracy of weather-based collision prediction systems improves by integrating such nuances and to clarify mechanisms through which these complex effects operate, such as influences of weather on migration intensity and collision avoidance behavior. Weather-based forecasts may allow refinement of collision mitigation approaches (e.g., reducing building lighting on certain nights or using temporary glass coverings or treatments). However, because challenges remain to communicating such temporally targeted actions and implementing them in a timely manner, other bird-friendly practices (e.g., season-long lighting reduction and permanent glass treatments) should continue to be prioritized.

The Aeolian Environment in Glen Torridon, Gale Crater, Mars

AbstractThe Mars Science Laboratory (MSL) rover spent a full martian year exploring the phyllosilicate‐bearing Glen Torridon trough on the flank of Aeolis Mons in Gale crater, enabling in‐depth assessment of aeolian processes. MSL encountered erosional and depositional features recording a long aeolian history. The trough has served as a long‐term conduit for sand transport, probably involving many cycles of sand accumulation and deflation. Rock abrasion textures indicate sand‐driving winds blowing W‐SW (opposite of abrasion textures on the Greenheugh Pediment above the trough floor). Indurated megaripple surfaces with 2–5 mm grains contrast with seasonally active ripples having finer maximum grain sizes, indicating more vigorous saltation in the past. Active ripples display a broad continuum of wavelengths, as well as coarser grains at crests than troughs, consistent with origins as impact ripples. Orientations of a wind streak extending from a large ripple field, and sandy wind tails behind obstacles, indicate sand is driven W‐SW in the current era, approximately along the trough axis. Erosion of drill tailings piles was strongly seasonal, enhanced during late spring and early summer (perihelion). Climate modeling suggests W‐SW sand transport can be attributed to seasonal enhancement of nighttime regional winds entering Gale crater from the N, combined with local katabatic winds flowing down the slopes of Aeolis Mons. However, it is unclear whether sand transport at Glen Torridon is primarily from these wind components combining and acting simultaneously, or occurring in serial at different times of night; field evidence supports both possibilities.

Visibility Predictions for Near-future Satellite Megaconstellations: Latitudes near 50° Will Experience the Worst Light Pollution

Abstract Megaconstellations of thousands to tens of thousands of artificial satellites (satcons) are rapidly being developed and launched. These satcons will have negative consequences for observational astronomy research, and are poised to drastically interfere with naked-eye stargazing worldwide should mitigation efforts be unsuccessful. Here we provide predictions for the optical brightnesses and on-sky distributions of several satcons, including Starlink, OneWeb, Kuiper, and StarNet/GW, for a total of 65,000 satellites on their filed or predicted orbits. We develop a simple model of satellite reflectivity, which is calibrated using published Starlink observations. We use this model to estimate the visible magnitudes and on-sky distributions for these satellites as seen from different places on Earth, in different seasons, and different times of night. For latitudes near 50° north and south, satcon satellites make up a few percent of all visible point sources all night long near the summer solstice, as well as near sunrise and sunset on the equinoxes. Altering the satellites’ altitudes only changes the specific impacts of the problem. Without drastic reduction of the reflectivities, or significantly fewer total satellites in orbit, satcons will greatly change the night sky worldwide.

Autonomic Nervous System Function During Sleep Among Women with Irritable Bowel Syndrome

This study compared heart-rate variability (HRV) indices of autonomic nervous system function during two nights of sleep between women with irritable bowel syndrome (IBS, n = 35) and healthy controls (n = 38), and among subgroups within the IBS sample based on predominant stool patterns. HRV measures were estimated in conjunction with polysomnographic sleep scoring to define sleep stage-specific autonomic indices. Overall, there were no differences in indicators of HRV between women with IBS and controls. However, within the IBS group, women with diarrhea-predominant IBS demonstrated significantly increased parasympathetic modulation and lower sympathetic/parasympathetic nervous system balance across sequential NREM periods and REM cycles compared to both constipation-predominant and alternating IBS subjects. These results suggest that differences in mean level of HRV between predominant bowel groups in IBS patients are large, and that this effect is consistent in the different sleep stages and at different times of night.

Changes in snoring during natural sleep identified by acoustic crest factor analysis at different times of night.

Sleep nasendoscopy can be used to identify the site of snoring but questions remain about how well a short assessment during drug-induced sleep reflects the natural condition. To investigate the uniformity of snoring during natural sleep we studied five patients (three men, two women) referred by their GPs for treatment of their snoring. A digital audio tape recorder captured the free-field snore sound at different times of night in hospital. Acoustic Crest Factor values were calculated on the 15 recordings made, having previously demonstrated that high crest factor values distinguish palatal from non-palatal snoring at sleep nasendoscopy. Some recordings showed reproducibility, but others showed substantial changes between recordings an hour apart. We infer that the snoring mechanism may change in some individuals during the night, with or without a change of snore site. We conclude a single recording, as in sleep nasendoscopy, may not be representative.

Observations on Yellow-bellied Sheath-tailed BatsSaccoliamus flaviventris(Peters, 1867) (Chiroptera: Emballonuridae)

The felling of a tree at Brightview, south-west of Brisbane containing a colony of 29 Saccoliamus flaviventris provided an opportunity to obtain data on morphology, ectoparasites, and sex ratios from 13 individuals killed during the tree felling. This is the largest known colony of this species. The limited availability of roost trees may be the cause of this large aggregation of bats. The importance of checking mature or dead trees prior to felling is demonstrated by the number of bats in this colony. Comparison of wing morphology showed no significant difference between the sexes, but significant differences occurred between bats from Brightview and Mt. Isa. Incidental observations on echolocation call structure and flight behaviour are also presented. The dimensions of the wings of S. flaviventris are similar to Nyctinomus australis, resulting in similar flight patterns for these species. Both species fly straight and rapidly above the canopy, although observations suggest they fly at different times of night, possibly due to differences in prey type.

Ecology of a bolas spider, Mastophora hutchinsoni: phenology, hunting tactics, and evidence for aggressive chemical mimicry.

Bolas spiders are relatively rare members of the large family known as orb weavers. Instead of using a typical web to capture prey, late-stadia and adult female bolas spiders swing a droplet of adhesive on a thread at flying insects. Mastophora hutchinsoni (Araneae: Araneidae) is one of five Mastophora species known from the United States and occurs over much of eastern North America. It is univoltine in Kentucky and overwinters in the egg stage. Spiderling emerged in May, the diminutive males matured in late June and early July, and females matured in early September. Eggs were produced from late September to late October or early November. This report is the first complete documentation of the population phenology of any bolas spider. Newly-emerged M. hutchinsoni spiderlings did not use a bolas, but instead hunted by positioning themselves on the underside of leaf margins where they ambushed small arthropods that crawled along the leaf margins. Subadult and adult female M. hutchinsoni used a bolas to capture moths. Only male moths were captured, specifically three species of Noctuidae (bristly cutworm, bronzed cutworm, and smoky tetanolita) and one species of Pyralidae (bluegrass webworm). Among 492 prey captured by more than twenty spiders at two sites during 1985 and 1986, smoky tetanolita moths and bristly cutworm moths accounted for 93% of the total. The flight behavior of approaching moths, the limited taxa caught from a large available moth fauna, and the fact that only males were caught support the hypothesis that the spider attracts its prey by producing chemicals which mimic the sex pheromones of these moth species. Adult female M. hutchinsoni frequently captured more than one moth species on a given night. The two most common prey species were active at different times of night, the bristly cutworm soon after nightfall and the smoky tetanolita generally between 11:00 p.m. and dawn. This pattern suggests that mating activity of these moth species may be temporally isolated, a common phenomenon when sympatric species have similar pheromones. If so, the spider could capture both species without producing different pheromone-mimicking compounds, simply by hunting during the activity period of each species.

Performance after awakening at different times of night

Naval ratings were roused during the night and presented themselves, dressed, for testing in a nearby room within 4 min. During the next 11 min, they were given tests of reaction time, calculation, and muscular coordination and steadiness. In all three tests, performance was well below the normal level achieved during the day. On different occasions, the men were roused at different times of night, and this factor influenced which task was affected most. Reaction time, with its intermittent call for rapid response, was impaired most in the early part of the night; the adding and coordination tasks, which demanded more continuous performance, were more affected later in the night. It is suggested that the early effects may be due to the depth of the preceding sleep, while the later ones may be influenced more by the trough in the circadian cycle of physiological activity.

Comparative Reproduction of Crambus harpipterus1 and Agriphila plumbifimbriella in Northern New Mexico2

Comparative reproduction was studied in sympatric populations of Agriphila plumbifimbriella Dyar and Crambus harpipterus Dyar at 2630 M elevation in the Jemez Mountains. Emergence from the pupa and mating are nocturnal events, with mating peaks possibly occurring at different times of night in the 2 species. Females of both species frequently mate twice. They oviposit maximally in mid afternoon in nature. Similar periodicity but increased oviposition occurs at 25°C and LD 14:10. Oviposition in darkness at 25°C in C. harpipterus , but not in A. plumbifimbriella , shows evidence of circadian control. Oviposition responsiveness to thoracic wounding is greater in C. harpipterus , which is twice as fecund as A. plumbifimbriella . Fore wing length is a better indicator of fecundity for C. harpipterus than for A. plumbifimbriella . Examination of reproductive tract morphology revealed basic similarities in the 2 species.