ABSTRACT
Cyclones can cause mass mortality of seabirds, sometimes wrecking thousands of individuals. The few studies to track pelagic seabirds during cyclones show they tend to circumnavigate the strongest winds. We tracked adult shearwaters in the Sea of Japan over 11 y and found that the response to cyclones varied according to the wind speed and direction. In strong winds, birds that were sandwiched between the storm and mainland Japan flew away from land and toward the eye of the storm, flying within ≤30 km of the eye and tracking it for up to 8 h. This exposed shearwaters to some of the highest wind speeds near the eye wall (≤21 m s-1) but enabled them to avoid strong onshore winds in the storm's wake. Extreme winds may therefore become a threat when an inability to compensate for drift could lead to forced landings and collisions. Birds may need to know where land is in order to avoid it. This provides additional selective pressure for a map sense and could explain why juvenile shearwaters, which lack a map sense, instead navigating using a compass heading, are susceptible to being wrecked. We suggest that the ability to respond to storms is influenced by both flight and navigational capacities. This may become increasingly pertinent due to changes in extreme weather patterns.
Subject(s)
Birds , Cyclonic Storms , Flight, Animal , Animals , Birds/physiology , Humans , Japan , WindABSTRACT
The present study sought to identify differences in the rates and predictors of risky sexual behavior among college students with and without attention-deficit hyperactivity disorder (ADHD). Current ADHD diagnosis, medication status among those with ADHD, executive functioning, substance use, comorbid anxiety, comorbid depression, and gender were identified as potential predictors of increased risky sexual behavior. Multiple group latent growth curve modeling was used to estimate trajectories of risky sexual behavior across four years of college among college students with ADHD (nmedicated = 99, nunmedicated = 105) and a comparison group (n = 217) recruited from colleges throughout the eastern United States (M age = 18.23 years, 53% female, 70% White). First-year college students with ADHD reported significantly higher rates of sexual risk behavior than their peers without ADHD, with no significant differences found based on medication status. Students with ADHD who were taking medication for ADHD reported significant decreases in risky sexual behavior over time. Among college students with ADHD, anxiety was related to increased current risky sexual behavior in the medicated group, while depression was predictive of decreased future risky sexual behavior in the unmedicated group. Alcohol and cannabis use were significantly associated with increased mean levels of risky sexual behavior across all three groups, and cannabis use was associated with decreased future risky sexual behavior within the comparison group. Executive functioning deficits and male gender were predictive of risky sexual behavior within the comparison group. The results demonstrate that college students with ADHD, regardless of medication status, are at an increased likelihood of engaging in risky sexual behavior.
Subject(s)
Attention Deficit Disorder with Hyperactivity , Humans , Male , Female , Adolescent , Attention Deficit Disorder with Hyperactivity/epidemiology , Students , Anxiety/epidemiology , Sexual Behavior , Risk-Taking , UniversitiesABSTRACT
Wind is fundamentally related to shelter and flight performance: two factors that are critical for birds at their nest sites. Despite this, airflows have never been fully integrated into models of breeding habitat selection, even for well-studied seabirds. Here, we use computational fluid dynamics to provide the first assessment of whether flow characteristics (including wind speed and turbulence) predict the distribution of seabird colonies, taking common guillemots Uria aalge breeding on Skomer Island as our study system. This demonstrates that occupancy is driven by the need to shelter from both wind and rain/wave action, rather than airflow characteristics alone. Models of airflows and cliff orientation both performed well in predicting high-quality habitat in our study site, identifying 80% of colonies and 93% of avoided sites, as well as 73% of the largest colonies on a neighbouring island. This suggests generality in the mechanisms driving breeding distributions and provides an approach for identifying habitat for seabird reintroductions considering current and projected wind speeds and directions.
ABSTRACT
It is fundamentally important for many animal ecologists to quantify the costs of animal activities, although it is not straightforward to do so. The recording of triaxial acceleration by animal-attached devices has been proposed as a way forward for this, with the specific suggestion that dynamic body acceleration (DBA) be used as a proxy for movement-based power. Dynamic body acceleration has now been validated frequently, both in the laboratory and in the field, although the literature still shows that some aspects of DBA theory and practice are misunderstood. Here, we examine the theory behind DBA and employ modelling approaches to assess factors that affect the link between DBA and energy expenditure, from the deployment of the tag, through to the calibration of DBA with energy use in laboratory and field settings. Using data from a range of species and movement modes, we illustrate that vectorial and additive DBA metrics are proportional to each other. Either can be used as a proxy for energy and summed to estimate total energy expended over a given period, or divided by time to give a proxy for movement-related metabolic power. Nonetheless, we highlight how the ability of DBA to predict metabolic rate declines as the contribution of non-movement-related factors, such as heat production, increases. Overall, DBA seems to be a substantive proxy for movement-based power but consideration of other movement-related metrics, such as the static body acceleration and the rate of change of body pitch and roll, may enable researchers to refine movement-based metabolic costs, particularly in animals where movement is not characterized by marked changes in body acceleration.
Subject(s)
Acceleration , Energy Metabolism , Animals , MovementABSTRACT
Many large birds rely on thermal soaring flight to travel cross-country. As such, they are under selective pressure to minimise the time spent gaining altitude in thermal updrafts. Birds should be able to maximise their climb rates by maintaining a position close to the thermal core through careful selection of bank angle and airspeed; however, there have been few direct measurements of either parameter. Here, we apply a novel methodology to quantify the bank angles selected by soaring birds using on-board magnetometers. We couple these data with airspeed measurements to parameterise the soaring envelope of two species of Gyps vulture, from which it is possible to predict 'optimal' bank angles. Our results show that these large birds respond to the challenges of gaining altitude in the initial phase of the climb, where thermal updrafts are weak and narrow, by adopting relatively high, and conserved, bank angles (25-35 deg). The bank angle decreased with increasing altitude, in a manner that was broadly consistent with a strategy of maximising the rate of climb. However, the lift coefficients estimated in our study were lower than those predicted by theoretical models and wind-tunnel studies. Overall, our results highlight how the relevant currency for soaring performance changes within individual climbs: when thermal radius is limiting, birds vary bank angle and maintain a constant airspeed, but speed increases later in the climb in order to respond to decreasing air density.
Subject(s)
Air Movements , Falconiformes/physiology , Flight, Animal/physiology , Altitude , Animals , Biomechanical Phenomena , Wings, AnimalABSTRACT
Many free-ranging predators have to make foraging decisions with little, if any, knowledge of present resource distribution and availability. The optimal search strategy they should use to maximize encounter rates with prey in heterogeneous natural environments remains a largely unresolved issue in ecology. Lévy walks are specialized random walks giving rise to fractal movement trajectories that may represent an optimal solution for searching complex landscapes. However, the adaptive significance of this putative strategy in response to natural prey distributions remains untested. Here we analyse over a million movement displacements recorded from animal-attached electronic tags to show that diverse marine predators-sharks, bony fishes, sea turtles and penguins-exhibit Lévy-walk-like behaviour close to a theoretical optimum. Prey density distributions also display Lévy-like fractal patterns, suggesting response movements by predators to prey distributions. Simulations show that predators have higher encounter rates when adopting Lévy-type foraging in natural-like prey fields compared with purely random landscapes. This is consistent with the hypothesis that observed search patterns are adapted to observed statistical patterns of the landscape. This may explain why Lévy-like behaviour seems to be widespread among diverse organisms, from microbes to humans, as a 'rule' that evolved in response to patchy resource distributions.
Subject(s)
Ecosystem , Feeding Behavior , Marine Biology , Models, Biological , Motor Activity , Predatory Behavior , Animals , Euphausiacea , Fractals , Gadiformes , Oceans and Seas , Population Density , Probability , Seals, Earless , Sharks , Spheniscidae , Tuna , TurtlesABSTRACT
Nonmedical prescription stimulant use (NPSU) is an ongoing public health crisis in the United States. There exists, however, a dearth of research investigating specific childhood risk factors that may contribute to this illicit use. Adverse childhood experiences (ACEs) may be a significant risk factor to address in the prevention and treatment of NPSU, as research has provided evidence for increased substance use, potentially including prescription stimulant misuse, among individuals who have experienced trauma. A systematic review of the literature was conducted to gather and synthesize research articles specifically examining the relationship between nonmedical prescription stimulant use in adults and the experience of adverse childhood experiences (ACEs). Four studies met all inclusion criteria and were included in the review. The results demonstrated that the nonmedical use of prescription stimulants in adults is significantly associated with ACEs, with a higher numerical count of ACEs associated with a greater likelihood of nonmedical prescription stimulant use. Gaps in the literature were identified, specifically noting a lack of information available regarding the relationship between ACEs and NPSU within gender- and racially diverse populations. The findings have implications for informing interventions related to ACEs and the misuse of prescription stimulant medication in adults.
ABSTRACT
Turbulence is a widespread phenomenon in the natural world, but its influence on flapping fliers remains little studied. We assessed how freestream turbulence affected the kinematics, flight effort and track properties of homing pigeons (Columba livia), using the fine-scale variations in flight height as a proxy for turbulence levels. Birds showed a small increase in their wingbeat amplitude with increasing turbulence (similar to laboratory studies), but this was accompanied by a reduction in mean wingbeat frequency, such that their flapping wing speed remained the same. Mean kinematic responses to turbulence may therefore enable birds to increase their stability without a reduction in propulsive efficiency. Nonetheless, the most marked response to turbulence was an increase in the variability of wingbeat frequency and amplitude. These stroke-to-stroke changes in kinematics provide instantaneous compensation for turbulence. They will also increase flight costs. Yet pigeons only made small adjustments to their flight altitude, likely resulting in little change in exposure to strong convective turbulence. Responses to turbulence were therefore distinct from responses to wind, with the costs of high turbulence being levied through an increase in the variability of their kinematics and airspeed. This highlights the value of investigating the variability in flight parameters in free-living animals.
Subject(s)
Columbidae , Stroke , Animals , Columbidae/physiology , Biomechanical Phenomena , Flight, Animal/physiology , Wind , Wings, Animal/physiologyABSTRACT
Predator-prey arms races have led to the evolution of finely tuned disguise strategies. While the theoretical benefits of predator camouflage are well established, no study has yet been able to quantify its consequences for hunting success in natural conditions. We used high-resolution movement data to quantify how barn owls (Tyto alba) conceal their approach when using a sit-and-wait strategy. We hypothesized that hunting barn owls would modulate their landing force, potentially reducing noise levels in the vicinity of prey. Analysing 87,957 landings by 163 individuals equipped with GPS tags and accelerometers, we show that barn owls reduce their landing force as they approach their prey, and that landing force predicts the success of the following hunting attempt. Landing force also varied with the substrate, being lowest on man-made poles in field boundaries. The physical environment, therefore, affects the capacity for sound camouflage, providing an unexpected link between predator-prey interactions and land use. Finally, hunting strike forces in barn owls were the highest recorded in any bird, relative to body mass, highlighting the range of selective pressures that act on landings and the capacity of these predators to modulate their landing force. Overall, our results provide the first measurements of landing force in a wild setting, revealing a new form of motion-induced sound camouflage and its link to hunting success.
Subject(s)
Predatory Behavior , Strigiformes , Animals , Strigiformes/physiology , Predatory Behavior/physiology , Sound , MotionABSTRACT
The metabolic costs of animal movement have been studied extensively under laboratory conditions, although frequently these are a poor approximation of the costs of operating in the natural, heterogeneous environment. Construction of "energy landscapes," which relate animal locality to the cost of transport, can clarify whether, to what extent, and how movement properties are attributable to environmental heterogeneity. Although behavioral responses to aspects of the energy landscape are well documented in some fields (notably, the selection of tailwinds by aerial migrants) and scales (typically large), the principles of the energy landscape extend across habitat types and spatial scales. We provide a brief synthesis of the mechanisms by which environmentally driven changes in the cost of transport can modulate the behavioral ecology of animal movement in different media, develop example cost functions for movement in heterogeneous environments, present methods for visualizing these energy landscapes, and derive specific predictions of expected outcomes from individual- to population- and species-level processes. Animals modulate a suite of movement parameters (e.g., route, speed, timing of movement, and tortuosity) in relation to the energy landscape, with the nature of their response being related to the energy savings available. Overall, variation in movement costs influences the quality of habitat patches and causes nonrandom movement of individuals between them. This can provide spatial and/or temporal structure to a range of population- and species-level processes, ultimately including gene flow. Advances in animal-attached technology and geographic information systems are opening up new avenues for measuring and mapping energy landscapes that are likely to provide new insight into their influence in animal ecology.
Subject(s)
Ecosystem , Energy Metabolism , Locomotion , Animals , Birds/physiology , GeographyABSTRACT
Individuals of varying backgrounds may respond differently to pharmacological interventions for depression. The Food and Drug Administration (FDA) recently approved the drug, esketamine, for adults with treatment-resistant depression. The current systematic review was executed to assess diversity inclusion in clinical trials for esketamine. Pubmed and Embase were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the systematic review yielded 11 final studies. All resultant studies reported female inclusion, 10 studies (91%) reported partial racial and ethnic inclusion, two studies (18%) reported socioeconomic factors, five studies (45%) executed subgroup analyses, and two studies (18%) addressed diversity in their limitations. Females were generally well represented, whereas non-White and Hispanic/Latinx participants were consistently underrepresented. Socioeconomic representation could not be assessed due to underreporting of this factor. Overall, the present review reports on the representation of various demographic subgroups in clinical trials for esketamine in depression and offers suggestions for future research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Subject(s)
Depression , Ketamine , Adult , Humans , Female , Depression/drug therapy , Ketamine/therapeutic useABSTRACT
BACKGROUND: Bio-logging devices play a fundamental and indispensable role in movement ecology studies, particularly in the wild. However, researchers are aware of the influence that attaching devices can have on animals, particularly on their behaviour, energy expenditure and survival. The way a device is attached to an animal's body has also potential consequences for the collected data, and quantifying the type and magnitude of such potential effects is fundamental to enable researchers to combine and compare data from different studies, as much as it is to improve animal welfare. For over two decades, large terrestrial birds have been in the focus of long-term movement ecology research, employing bio-logging devices attached with different types of harnesses. However, comparative studies investigating the effects of different harness types used on these species are scarce. METHODS: In this study, we tested for potential differences in data collected by two commonly used harness types, backpack and leg-loop, on the flight performance of 10 individuals from five soaring raptor species, equipped with high resolution bio-logging devices, in the same area and time. We explored the effect of harness type on vertical speed, airspeed, glide ratio, height above sea level, distance travelled, proportion of soaring and flapping behaviour, and VeDBA (a proxy for energy expenditure) between and within individuals, all used as fine-scale measures of flight performance. RESULTS: Birds equipped with leg-loops climbed up to 0.36 ms[Formula: see text] faster, reached 25.9% greater altitudes while soaring and spent less time in active flight compared to birds equipped with backpacks, suggesting that backpack harnesses, compared to leg-loops, might cause additional drag affecting the birds' flight performance. A lower VeDBA, a lower rate of sinking while gliding and slightly higher glide ratio and airspeeds were also indicative of less drag using leg-loops, even though the effect on these parameters was comparable to inter-individual differences. CONCLUSIONS: Our results add to the existing literature highlighting the design-related advantages of leg-loops, and support the use of leg-loops as a better alternative to backpack harnesses for large soaring birds, when possible. Our study also highlights how apparently small changes in device attachment can lead to notable improvements in tagging practice, with implications for animal welfare, data interpretation and comparability.
ABSTRACT
The aim of the present systematic review was to discuss the reported efficacy of executive functioning training techniques among adolescents. A systematic review of the literature was conducted to retrieve and consolidate findings from articles evaluating executive functioning training techniques among adolescents. A total of 26 articles were located that examined the role of executive functioning training techniques among adolescents (age 10-19 years). Articles retrieved enabled comparison across psychiatric and medical diagnoses including attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), as well as adolescents with physical health concerns. Results revealed that among typically developing adolescents, executive functioning training was non-significant or yielded small effect size improvements in executive functioning as measured by behavioral and neuroimaging tasks among 62.5% of studies reviewed. In contrast, in those with medical conditions, ASD, ADHD, and conduct disorder, all but two studies reviewed yielded a medium to large effect size, supporting the effectiveness of EF training. Future research is needed to identify the long-term efficacy of these treatments, as well as their generalizability to real-world conditions.
ABSTRACT
Background: Usher syndrome is the most common cause of deaf-blindness, affecting up to 1 in 6000 people. Multidisciplinary care is required to maximize outcomes for individuals and families. This study assessed awareness of Usher Syndrome amongst allied health clinicians who provide care related to the primarily affected senses of hearing and vision, ie, optometry, orthoptics and audiology. Methods: A prospective cross-sectional online survey of clinicians working in Australian university-affiliated clinics (7 optometry, 1 orthoptics and 4 audiology) was completed between September 2021 and January 2022. Questions were asked about the cause, common symptoms, and awareness of health professions who manage Usher syndrome. Results: The 27 audiologists, 40 optometrists, and 7 orthoptists who completed the survey included 53 females (71.6%), had an average age of 37 years (range 24-70), and had an average duration of clinical experience of 13 years (range 1-45 years). The majority of respondents correctly identified Usher syndrome as a genetic condition (86%), identified at least two of the affected senses (97%), and identified the progressive nature of the vision and hearing losses (>90%). Awareness of vestibular dysfunction and its characteristics was low, as was knowledge of the key treatment roles that speech pathologists, genetic counsellors and geneticists play in the management of Usher Syndrome. The majority of respondents also did not identify important aspects of care within their own discipline. Conclusion: This study has shown that there is a need for targeted education to be delivered to hearing and vision care allied health clinicians to raise awareness of the vestibular impacts and aspects of vision loss experienced by people with Usher syndrome. This education needs to target the broad range of clinicians who have a key role in providing multidisciplinary care (including speech pathologists, geneticists, and genetic counsellors) and to identify the key aspects of good-quality multidisciplinary care.
ABSTRACT
Storms can cause widespread seabird stranding and wrecking,1,2,3,4,5 yet little is known about the maximum wind speeds that birds are able to tolerate or the conditions they avoid. We analyzed >300,000 h of tracking data from 18 seabird species, including flapping and soaring fliers, to assess how flight morphology affects wind selectivity, both at fine scales (hourly movement steps) and across the breeding season. We found no general preference or avoidance of particular wind speeds within foraging tracks. This suggests seabird flight morphology is adapted to a "wind niche," with higher wing loading being selected in windier environments. In support of this, wing loading was positively related to the median wind speeds on the breeding grounds, as well as the maximum wind speeds in which birds flew. Yet globally, the highest wind speeds occur in the tropics (in association with tropical cyclones) where birds are morphologically adapted to low median wind speeds. Tropical species must therefore show behavioral responses to extreme winds, including long-range avoidance of wind speeds that can be twice their operable maxima. By contrast, Procellariiformes flew in almost all wind speeds they encountered at a seasonal scale. Despite this, we describe a small number of cases where albatrosses avoided strong winds at close range, including by flying into the eye of the storm. Extreme winds appear to pose context-dependent risks to seabirds, and more information is needed on the factors that determine the hierarchy of risk, given the impact of global change on storm intensity.6,7.
Subject(s)
Flight, Animal , Wind , Animals , Flight, Animal/physiology , Birds/physiology , Adaptation, Physiological , Feeding Behavior/physiologyABSTRACT
Emily Shepard introduces ways flying animals conserve energy inflight.
Subject(s)
Energy Metabolism , Flight, Animal , AnimalsABSTRACT
All animals that operate within the atmospheric boundary layer need to respond to aerial turbulence. Yet little is known about how flying animals do this because evaluating turbulence at fine scales (tens to approx. 300 m) is exceedingly difficult. Recently, data from animal-borne sensors have been used to assess wind and updraft strength, providing a new possibility for sensing the physical environment. We tested whether highly resolved changes in altitude and body acceleration measured onboard solo-flying pigeons (as model flapping fliers) can be used as qualitative proxies for turbulence. A range of pressure and acceleration proxies performed well when tested against independent turbulence measurements from a tri-axial anemometer mounted onboard an ultralight flying the same route, with stronger turbulence causing increasing vertical displacement. The best proxy for turbulence also varied with estimates of both convective velocity and wind shear. The approximately linear relationship between most proxies and turbulence levels suggests this approach should be widely applicable, providing insight into how turbulence changes in space and time. Furthermore, pigeons were able to fly in levels of turbulence that were unsafe for the ultralight, paving the way for the study of how freestream turbulence affects the costs and kinematics of animal flight.
Subject(s)
Flight, Animal , Wind , Animals , Biomechanical Phenomena , ColumbidaeABSTRACT
Remaining cohesive on the move can be beneficial for animal groups. As such, animal groups have evolved coordination mechanisms such as leadership to resolve navigational conflicts of interest. Consistent "leaders" may have an intrinsic advantage over "followers" which compromise on their preferred route to retain cohesion, which highlights the question of the inter-individual variation (phenotype) that can predict leadership. Studies in both birds and fish have revealed that intrinsically faster individuals can lead movements, and leading movements propagate from the front edge of the flock/shoal. However, these experiments are generally conducted in relatively "familiar" environments, where the degree of compromise between the "leaders" and "followers" is low. We suggested that inter-individual differences in route efficiency, while not explanatory of leadership from familiar locations, may emerge as predictors of leadership from unfamiliar locations. We tested this prediction - and the potential impact of multiple other behavioral, morphological and "in-flight" phenotypes on leadership - using two groups of homing pigeons (Columba livia) (N = 16), a classic model species of leadership. We recorded N = 966 unique GPS trajectories from birds in (i) solo and familiar, and (ii) solo and unfamiliar contexts to measure solo speed and solo route efficiency; and (iii) group and familiar, and (iv) group and unfamiliar contexts to assess group leadership. Pigeon leadership hierarchies were similar across environmental context (i.e., familiarity). However, we found that no covariates could consistently predict leadership score in either context.
Subject(s)
Columbidae , Homing Behavior , Animals , Flight, Animal , Leadership , PhenotypeABSTRACT
In recent years, rates of prescription stimulant misuse have increased among young adults ages 18 to 25 along with increases in dispensing rates of these medications. Preliminary studies suggest that college students with Attention-Deficit Hyperactivity Disorder (ADHD) may be more likely to misuse their stimulant medication than their non-ADHD peers. Research is needed to further explore possible rates, correlates, and outcomes of prescription stimulant misuse among college students with and without ADHD. Data regarding study strategies, psychological functioning, stimulant misuse, and GPA were collected from students from universities within the US (N = 144), showing significantly higher rates of misuse among college students with ADHD. With depression and anxiety entered into the predictive model, inattentive symptoms were the only significant predictor of misuse in the full sample. The present findings have implications for academic interventions aimed at supporting the success of college students with and without ADHD and inform academic outcomes of prescription stimulant misuse.
Subject(s)
Attention Deficit Disorder with Hyperactivity , Central Nervous System Stimulants , Substance-Related Disorders , Adolescent , Adult , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/drug therapy , Attention Deficit Disorder with Hyperactivity/epidemiology , Central Nervous System Stimulants/therapeutic use , Humans , Students/psychology , Substance-Related Disorders/diagnosis , Substance-Related Disorders/epidemiology , Universities , Young AdultABSTRACT
Quantifying stress and energetic responses in animals are major challenges, as existing methods lack temporal resolution and elevate animal stress. We propose "wake respirometry," a new method of quantifying fine-scale changes in CO2 production in unrestrained animals, using a nondispersive infrared CO2 sensor positioned downwind of the animal, i.e., in its wake. We parameterize the dispersion of CO2 in wakes using known CO2 flow rates and wind speeds. Tests with three bird species in a wind tunnel demonstrated that the system can resolve breath-by-breath changes in CO2 concentration, with clear exhalation signatures increasing in period and integral with body size. Changes in physiological state were detectable following handling, flight, and exposure to a perceived threat. We discuss the potential of wake respirometry to quantify stress and respiratory patterns in wild animals and provide suggestions for estimating behavior-specific metabolic rates via full integration of CO2 production across the wake.