Flight Distance Research Articles

Validating the use of pen scores to capture behaviors expressed by cattle unrestrained in a pen1.

Many subjective methods exist to assist producers in evaluating temperament. Use of a pen test, which allows behavior to be observed in a non-restrained setting, may be an effective method to evaluate temperament by allowing more variation among animals to be expressed as compared to a restrained test. The objective of this study was to analyze video recordings of penned calves to determine whether the repertoire of behaviors they expressed were adequately captured by their individual (IPS) and group (GPS) pen scores. In each of 3 yr, 40 predominantly Angus commercial Bos taurus heifers, 2-wk post weaning, were assessed monthly in 3 consecutive months (recording periods). After routine handling through a weigh crate and squeeze chute, each heifer was released individually into a pen (12 x 6 m). Their response to 30s of human presence within the pen was evaluated. They were then joined in groups of four in a larger (12 x 8 m) pen and re-evaluated for 30s in a group setting. An IPS and GPS was assigned using an ethogram ranging from 1 (docile) to 6 (aggressive). This interaction was also video recorded. Using the videos, the explicit behaviors captured by each pen score were investigated using Noldus Observer software. Data were analyzed with ANOVA using SAS. Within each recording period, the concordance of pen scores with the repertoire of behaviors expressed were compared. In the group setting, heifers could not be clearly distinguished on video and were instead assigned the average GPS of the group. Heifers with higher IPS and average GPS categories had larger flight zone sizes and reached faster paces for longer periods of time. Furthermore, heifers with lower IPS appeared more neutral to the presence of a human and moved around less often. Ethograms for pen score successfully delineated the temperament of heifers. The use of such scores can provide a valuable on-farm assessment of cattle behavior during routine handling.

Assignment Technology Based on Improved Great Wall Construction Algorithm

The problem of allocating multiple UAV tasks is a complex combinatorial optimization challenge, involving various constraints. This paper presents an autonomous multi-UAV cooperative task allocation method based on an improved Great Wall Construction Algorithm. A model integrating battlefield environmental factors, 3D terrain data, and threat assessments is developed for optimized task allocation and trajectory planning. The algorithm is enhanced using a good point set initialization strategy, Gaussian distribution estimation, and a Cauchy reorganization variant. The simulation results show that replacing straight-line distances with actual flight distances leads to more rational mission sequences, improving combat effectiveness under realistic terrain and threat conditions. The enhanced algorithm demonstrates superior accuracy and faster convergence.

Impact of tourism on bird behavior: A comparison of flight initiation distance between birds in areas of tourist and non-tourist attraction.

Tourism, as an important manifestation of urbanization, is becoming increasingly popular. Although it offers numerous advantages for the local community, it also exerts a multifaceted impact on local wildlife. Previous research on the effects of tourism has mainly focused on protected areas or tourist spots, rarely considering the surrounding non-tourist attraction areas. Therefore, exploring the behavioral differences of wildlife in response to different levels of human disturbance in areas of tourist and non-tourist attraction will contribute to a more comprehensive understanding of the impact of tourism activities on animals. This study compared the differences in the flight initiation distance (FID) of Eurasian tree sparrows (Passer montanus) between areas of tourist attraction (Xijiang Miao Village and Zhaoxing Dong Village) and non-tourist attraction (surrounding villages) in Guizhou Province, southwestern China. We found that Eurasian tree sparrows in areas of tourist attraction exhibited shorter FIDs than those in areas of non-tourist attraction, suggesting that Eurasian tree sparrows inhabiting areas with higher levels of human disturbance demonstrate a greater ability to adapt to anthropogenic disturbance. Moreover, the FID of Eurasian tree sparrows was less influenced by flock size than by tourist attraction category. It highlights the notable impact of human activities on wildlife, contributing to the scientific management and protection of birds in urban environments.

Simulating the break-up, debris formation and throw of concrete structures under explosive loading

Malicious acts, but likewise unintended accidental explosions, can lead to severe structural damage and resulting debris throw, which poses a significant threat to humans and facilities. Until now, risk analysis is based mainly on empirical data, since the reliable simulation of structural break-up, dissolution and emergence of secondary fragments for real structures is still challenging. In this paper, we investigate the application of a mesoscale description of concrete with finite elements to predict the dispersal of fragments out of dynamically loaded concrete specimens. We demonstrate that the approach delivers accurate predictions for maximum velocity and total debris mass. Further, it is even able to to resolve the debris mass distribution with very reasonable quality, a result rarely found in literature up to today. The detailed resolution of the debris field allows furthermore a more thorough determination of the aerodynamic factors governing the subsequent flight phase. We compare the results using different assumptions in terms of flight distances and safety maps.

When injustice triggers retaliation: examining the dual impact of power distance orientation

Purpose This study aims to examine the relationship between organizational justice and employee retaliation. By incorporating psychological contract violation (PCV) as a mediating variable, this study uncovers the underlying psychological pathways through which perceptions of unfairness lead to employees’ decisions to retaliate. Furthermore, this study examines individual power distance orientation as a moderating factor, offering insights into how cultural values influence individual perceptions of and reactions to perceived injustice. Design/methodology/approach Through a two-wave survey design, the authors screened for full-time employees through Qualtrics. The authors have used confirmatory factor analysis to examine the measurement model fit. In addition, the authors have performed regression-based path analysis using Mplus to test their hypotheses. Findings This study has found that PCV fully mediates the impact of organizational justice on employee retention. The results also revealed two distinct mechanisms through which power distance orientation affects individual reactions to perceived unfairness. Specifically, it was also found that cognitive and motivational effects occur simultaneously yet in the opposite direction, such that power distance orientation weakens the impact of procedural justice on PCV but exacerbates the relationship between PCV and retaliation directed at supervisors and coworkers. Originality/value The analysis of the mediating role of PCV enables the authors to tease apart the cognitive and motivational impacts of power distance orientation, shedding light on existing mixed empirical findings. In addition, this study advances the understanding of psychological contract development by illustrating the impact of cultural orientation, such that it not only aligns individuals’ expectations with prevailing cultural norms but also influences the significance attributed to these expectations. Lastly, the study contributes to cross-cultural research on organizational justice and retaliation by showing individual perceptions of and reactions to lack of justice depending on cultural orientations.

Herons in Aquafarms Are More Fearful of Humans.

Herons (Ardeidae), an important group in wetland ecosystems, have a particularly strong relationship with humans. However, their predation on farmed fish and shrimp in aquafarms can lead to economic losses for local fish farmers. Consequently, notable conflicts arise between fish farmers and herons. Fish farmers adopt various measures to deter herons from "stealing" their fish; however, there is limited research on the behavioral responses of herons under such pressures of human disturbance. Flight initiation distance (FID) is an important manifestation of avian anti-predation behavior and serves as an indicator of birds' tolerance to human disturbance. This study investigated the potential variations in tolerance to human disturbance between the little egret (Egretta garzetta) and the Chinese pond heron (Ardeola bacchus) in "stealing" environments (aquafarm environments) and non-aquafarm environments in Hainan and Guangdong Provinces, south China, using FID as an indicator. Herons in aquafarm environments were less tolerant (having longer FIDs) to human disturbance compared to herons in non-aquafarm environments. The main cause of this phenomenon could be the harsh deterrents used by humans to prevent herons from "stealing" fish. These deterrents increase the predation risk for herons when "stealing" in aquafarms, causing them to exhibit less tolerance to human disturbance. Our study increases understanding of the behavioral response patterns of herons in human-wildlife conflicts and provides valuable insights for more scientific and rational management and protection of Ardeidae species.

Combining radio-telemetry and radar measurements to test optimal foraging in an aerial insectivore bird

Optimal foraging theory posits that foragers adjust their movements based on prey abundance to optimize food intake. While extensively studied in terrestrial and marine environments, aerial foraging has remained relatively unexplored due to technological limitations. This study, uniquely combining BirdScan-MR1 radar and the Advanced Tracking and Localization of Animals in Real-Life Systems biotelemetry system, investigates the foraging dynamics of Little Swifts (Apus affinis) in response to insect movements over Israel’s Hula Valley. Insect movement traffic rate (MoTR) substantially varied across days, strongly influencing swift movement. On days with high MoTR, swifts exhibited reduced flight distance, increased colony visit rate, and earlier arrivals at the breeding colony, reflecting a dynamic response to prey availability. However, no significant effects were observed in total foraging duration, flight speed, or daily route length. Notably, as insect abundance increased, inter-individual distances decreased. These findings suggest that Little Swifts optimize their foraging behavior in relation to aerial insect abundance, likely influencing reproductive success and population dynamics. The integration of radar technology and biotelemetry systems provides a unique perspective on the interactions between aerial insectivores and their prey, contributing to a comprehensive understanding of optimal foraging strategies in diverse environments.

Combining radio-telemetry and radar measurements to test optimal foraging in an aerial insectivore bird.

Optimal foraging theory posits that foragers adjust their movements based on prey abundance to optimize food intake. While extensively studied in terrestrial and marine environments, aerial foraging has remained relatively unexplored due to technological limitations. This study, uniquely combining BirdScan-MR1 radar and the Advanced Tracking and Localization of Animals in Real-Life Systems biotelemetry system, investigates the foraging dynamics of Little Swifts (Apus affinis) in response to insect movements over Israel's Hula Valley. Insect movement traffic rate (MoTR) substantially varied across days, strongly influencing swift movement. On days with high MoTR, swifts exhibited reduced flight distance, increased colony visit rate, and earlier arrivals at the breeding colony, reflecting a dynamic response to prey availability. However, no significant effects were observed in total foraging duration, flight speed, or daily route length. Notably, as insect abundance increased, inter-individual distances decreased. These findings suggest that Little Swifts optimize their foraging behavior in relation to aerial insect abundance, likely influencing reproductive success and population dynamics. The integration of radar technology and biotelemetry systems provides a unique perspective on the interactions between aerial insectivores and their prey, contributing to a comprehensive understanding of optimal foraging strategies in diverse environments.

Social Security: Individuals in Socially Reciprocal Groups May Perceive Security from Predators

Abstract One of the most explored factors mediating antipredator behavior is group size, which generally predicts individuals in larger social groups allocate less time to antipredator vigilance while foraging. However, group size alone does not capture the full complexity of sociality. An individual’s ‘sense of security’, or their perceived risk of predation, is also influenced by an individual’s social connections. Further, group social structure – the pattern of all social interactions in a group – could explain additional variation in perceptions of security for the individuals that reside in the group. Using the time allocated to vigilance during foraging and flight initiation distance (FID) to quantify individuals’ social security, we explored whether individual yellow-bellied marmots (Marmota flaviventer) in tightly connected social groups looked less while foraging and had shorter FIDs. Using linear mixed effect models, we found modest support for the Social Security Hypothesis; individuals in more socially reciprocal groups may spend less time looking for predators while foraging. No measure of group social structure explained variation in FID. Measures of the immediate environment (the number of individuals within 10 meters for vigilance and the distance from burrow and alert distance for FID) had effect sizes an order of magnitude greater than measures of social structure, suggesting an individual’s immediate environment has more of an impact on their antipredator behavior than the structure of their social group.

Weak evidence for a relationship between group size and flight initiation distance in response to underwater human presence in an exploited fish species

Group size can influence flight initiation distance (FID), a key antipredator behavior, in many animal species. In fishes, however, the effect of group size on FID remains unclear. Two different mechanisms might explain a putative relationship between group size and FID. If fish benefited from having more vigilant individuals around, we would expect group size to be positively associated with FID (considering collective vigilance in the context of the many eyes hypothesis). By contrast, if fish benefited from a predator dilution effect, we would expect group size to be negatively associated with FID. Importantly, such relationships should be critically sensitive to background risk levels. We capitalized on FID observations inside and outside marine protected areas and simulated risk by having a risky spearfisher or a non-risky snorkeler swim towards white seabream (Diplodus sargus) to estimate the relationship between FID and group size. Model selection provides weak evidence that group size positively influences FID of white seabream when group size was modelled two ways: categorically (alone vs. shoal), and continuously (range 2–15). While the results suggest that overall group size has a measurable impact on FID, the presence of spearfishers or snorkelers had a weak effect on the relationship of group size and FID, which seems to be more sensitive exclusively to the protection level (inside/outside marine protected areas). Our findings align with previous studies showing mixed results on the relationship between group size and FID. This study underscores the complexity of antipredator behaviors in natural settings and suggests that multiple interlinked factors, rather than group size alone, drive FID in fishes. Future research should integrate field observations, laboratory experiments, and modeling to study the ecological influence of group size on FID more comprehensively.

Assessment of Groundwater (Main Usable Aquifer) Vulnerability to Seawater Intrusion in the Polish Baltic Coastal Region

The inflow of saline water reduces water quality and limits its use as drinking water. The risk of seawater intrusion into groundwater along the Polish coastline was assessed using two methods. The vulnerability method (GALDIT) considered six aquifer parameters. The second method focused exclusively on the chemical parameters of groundwater: EC, seawater mixing index (SMI), rHCO₃/rCl, rNa/rCl, and the concentrations of Cl− and Br. The analysis focused on monitoring results collected from points located within 5 km of the Baltic Sea coastline. Both risk assessment methods used a division into three risk classes (low, moderate, and high), but the results differed between the two approaches. A comparison of the results from both classification methods was conducted, followed by a comprehensive risk assessment integrating the outcomes of both approaches. No straightforward relationship was observed between individual threat assessment parameters and distance from the sea. However, when the overall assessment, incorporating multiple parameters, was considered, such a relationship emerged. The classes of seawater intrusion risk differ in terms of the medians and ranges of individual parameters. Ratios such as rHCO3/rCl, rCa/rMg, and Cl/Br play a significant role in risk assessment, whereas the rNa/rCl ratio has a relatively smaller impact. Seawater intrusion risk should be assessed based on multiple parameters. The highest risk of seawater intrusion occurs within approximately 800 m of the coastline.

Distance of flight of cosmic-ray muons to study dynamics of the upper muosphere

Abstract. The Earth can be divided by main layers, including the atmosphere, geosphere (solid Earth), and biosphere, depending on its predominant component. In this work, the layer of the Earth which constantly contains a high concentration of muons (∼8×1012 muons) and its upper border are respectively defined as the muosphere and muopause. The altitude of the muosphere spans from the lower stratosphere to the upper crust of the Earth. In order to study its dynamics, the muopause height was spatiotemporally studied with a new kind of technique called the distance of flight (DOF), which utilizes variations in the muon's decay length. In this work, (A) numerical modeling was performed, and it was clarified that seasonal variations in the cosmic muon flux are predominantly ruled by muopause dynamics; (B) the muon data were compared with the balloon-based measurement results, and it was confirmed that muopause dynamics are closely related to lower-stratospheric height variations. Since the muopause is the region spanning the area between the upper troposphere and the lower stratosphere, the potential of the current distant of flight (DOF) approach needs to be further investigated by cross-comparing related case studies and other atmospheric climate datasets.

The Mechanisms of Inclusive Leadership on Newcomers' Proactive Socialization Behaviors-An Exploration Based on the Proactive Motivation Model.

This study advances newcomers' socialization research by identifying and investigating the antecedents of newcomers' proactive behaviors, a perspective often overlooked within the current studies, which primarily focuses on the outcomes of such behaviors. Based on the proactive motivation model, our core hypothesis is that inclusive leadership allows newcomers to experience psychological changes in control beliefs (can-do motivation), state promotion focus (reason-to motivation), and positive affect (energized-to motivation), which are stimulated following proactive behaviors. We further consider an individual values variable-individual power distance orientation-as the boundary condition on the influence of inclusive leadership. Research was conducted on 353 newcomers with less than one year of work experience to test the above hypothesis. The results show that inclusive leadership positively and indirectly influences the newcomers' proactive behaviors via state promotion focus and positive affect. However, the mediating effect of control beliefs was not significant. Furthermore, the positive association between inclusive leadership and two kinds of newcomer proactive motivations, and their accompanying indirect impacts on newcomers' proactive behaviors, was proved stronger at lower levels of individual power distance orientation. Additionally, it has been discovered in a follow-up complementary study that the effect of control beliefs on newcomers' proactive behaviors is transmitted through positive affect.

Do Oystercatchers hate drones? A comparison of flight initiation distances of four wader species in response to drone intrusion

Do Oystercatchers hate drones? A comparison of flight initiation distances of four wader species in response to drone intrusion

Feedback on Escape Behavior of Birds Under Different Hunger Pressure.

The risk of predation has always been a significant impact on wild birds. Birds, facing with limited energy, must balance their investment between foraging and vigilance. There were currently limited understandings of the vigilant behavior feedback of birds under different hunger pressure. Therefore, we employed the White-browed laughingthrush (Pterorhinus sannio) and White wagtail (Motacilla alba) as research subjects to carry out experiments in winter, in exploring the tolerance of birds to external stress under different hunger pressure. After a night of energy expenditure, individuals of both species faced greater hunger pressure in the morning. The results of general linear models showed that the flight initiation distance (FID) of both species in the morning (7:00-9:00) was significantly shorter than that in the evening (16:00-18:00). Additionally, when the weather was cold (daily minimum temperature ≤ 5°C), the FID of the White-browed laughingthrush and White wagtail was significantly shorter in the morning, as same as the results of general linear models. However, when the weather was warm (daily minimum temperature ≥ 10°C), there was no significant difference even though the FID average of both species was shorter in the morning than in the evening. These suggested that the consumption and supplementation of energy are very important for birds, as the higher their hunger pressure, the greater their willingness to forage and take on risk, especially in cold winter.

When should a runner on third base advance? Analyzing factors that influence the success of sacrifice flies in US Major League Baseball games

This study aims to identify factors influencing the success of sacrifice flies in US Major League Baseball. From baseball-tracking outputs of official games during 2023–2024, 3439 flyouts reaching >50 m from home plate when a runner was on third base with <2 outs were analyzed. A multiclass classification model was developed to predict results of runners at third base (i.e., stayed at third base, tagged out at home plate, or scored on a sacrifice fly) from batted ball kinematics, runner's sprint speed (SS), the fielder's arm strength (AS), and ballpark. Average probability scores were compared by systematically altering these inputs. The results show that (i) the model accurately predicted the runner staying at third and sacrifice flies (F-score ≥ 0.842) but could not predict tag outs (0.057), (ii) nearly all flyouts reaching <70 m from home plate would result in the runner staying on third base, whereas the runner usually would score when the flyouts reach ≥85 m, and (iii) the shortest flight distance required for a sacrifice fly could be expressed by a simplified linear function: distance = 87.2–3.1SS + 0.7AS. This function will help set targets for better decision-making and greater success of sacrifice flies.

Flight initiation distance is repeatable and geographically flexible in greylag geese Anser anser

The decision to flee from an approaching threat represents a trade‐off between the costs and benefits of flight. In research to date, particular interest has been given to the effects of urbanisation on predator escape behaviour. However, these differences are most often studied at the population rather than individual level, which makes it difficult to disentangle whether site‐specific differences in predator avoidance are due to behavioural plasticity or non‐random distribution of behavioural phenotypes. In this study, we measured flight initiation distances – a widely used proxy for fearfulness or boldness – in a free‐roaming, human‐habituated, and colour‐banded population of greylag geese Anser anser. First, we tested whether individuals flexibly adjusted their flight initiation distance based on environmental context by approaching the same individuals at two sites with different levels of human presence. Second, we examined whether flock members show consistent differences in their flight initiation distance towards unfamiliar humans. Our results suggest that greylag geese can adjust their behaviour based on environmental context and show individual differences in flight initiation distance that are consistent both within and across years. When individuals regularly move between foraging sites, establishing site‐specific responses to potential threats may allow them to optimise their escape response and thereby avoid unnecessary energetic and opportunity costs.Keywords: Anser anser, behavioural plasticity, boldness, escape behaviour, flight initiation distance

The Effect of Wing-Flashing Behavior on Prey Capture Performance of San Clemente Loggerhead Shrikes.

Loggerhead shrikes (Lanius ludovicianus) are medium-sized predatory songbirds that feed on arthropods and vertebrates. Prior to attacking their prey, shrikes have been observed performing "wing-flashing" behavior, consisting of rapid fluttering of the wings that seems to emphasize the white patches on their dorsal surfaces. We sought to quantify this behavior by analyzing videos of San Clemente loggerhead shrikes attacking insect and vertebrate prey, to understand whether and how wing-flashing affects prey capture performance. We measured predictors of wing-flashing behavior, wing-flashing kinematics, and prey capture performance in terms of the number of strikes required to kill prey, prey strike durations, prey escape distances, and prey survival probabilities. Juveniles were more likely to perform wing-flashing behavior than adults, and lizards elicited wing-flashing more than mice and crickets. Adult males tended to flash their wings faster than juvenile males, and although wing-flashing rates were similar between ages for females and across prey types (∼15 Hz), shrikes flashed their wings for longer durations toward lizards. Wing-flashing was generally associated with fewer strikes to kill prey and resulted in longer prey strike durations for adult shrikes, longer prey escape distances, and lower prey survival probabilities for male shrikes. Our results suggest that wing-flashing behavior of loggerhead shrikes enhances their prey capture performance, possibly by stimulating prey to move-and not to move, depending on prey type-making them more vulnerable to predatory strikes.

Do agricultural practices on meadows reduce or increase flight initiation distance in the white stork ciconia ciconia?

Do agricultural practices on meadows reduce or increase flight initiation distance in the white stork ciconia ciconia?

Comparative Analysis of Physiological Vergence Angle Calculations from Objective Measurements of Gaze Position.

Eccentric photorefractometry is widely used to measure eye refraction, accommodation, gaze position, and pupil size. While the individual calibration of refraction and accommodation data has been extensively studied, gaze measurements have received less attention. PowerRef 3 does not incorporate individual calibration for gaze measurements, resulting in a divergent offset between the measured and expected gaze positions. To address this, we proposed two methods to calculate the physiological vergence angle based on the visual vergence data obtained from PowerRef 3. Twenty-three participants aged 25 ± 4 years viewed Maltese cross stimuli at distances of 25, 30, 50, 70, and 600 cm. The expected vergence angles were calculated considering the individual interpupillary distance at far. Our results demonstrate that the PowerRef 3 gaze data deviated from the expected vergence angles by 9.64 ± 2.73° at 25 cm and 9.25 ± 3.52° at 6 m. The kappa angle calibration method reduced the discrepancy to 3.93 ± 1.19° at 25 cm and 3.70 ± 0.36° at 600 cm, whereas the linear regression method further improved the accuracy to 3.30 ± 0.86° at 25 cm and 0.26 ± 0.01° at 600 cm. Both methods improved the gaze results, with the linear regression calibration method showing greater overall accuracy.