38 research outputs found
Assessing bird avoidance of high-contrast lights using a choice test approach: implications for reducing human-induced avian mortality
Background: Avian collisions with man-made objects and vehicles (e.g., buildings, cars, airplanes, power lines) have increased recently. Lights have been proposed to alert birds and minimize the chances of collisions, but it is challenging to choose lights that are tuned to the avian eye and can also lead to avoidance given the differences between human and avian vision. We propose a choice test to address this problem by first identifying wavelengths of light that would over-stimulate the retina using species-specific perceptual models and by then assessing the avoidance/attraction responses of brown-headed cowbirds to these lights during daytime using a behavioral assay.
Methods: We used perceptual models to estimate wavelength-specific light emitting diode (LED) lights with high chromatic contrast. The behavioral assay consisted of an arena where the bird moved in a single direction and was forced to make a choice (right/left) using a single-choice design (one side with the light on, the other with the light off) under diurnal light conditions.
Results: First, we identified lights with high saliency from the cowbird visual perspective: LED lights with peaks at 380 nm (ultraviolet), 470 nm (blue), 525 nm (green), 630 nm (red), and broad-spectrum (white) LED lights. Second, we found that cowbirds significantly avoided LED lights with peaks at 470 and 630 nm, but did not avoid or prefer LED lights with peaks at 380 and 525 nm or white lights.
Discussion: The two lights avoided had the highest chromatic contrast but relatively lower levels of achromatic contrast. Our approach can optimize limited resources to narrow down wavelengths of light with high visual saliency for a target species leading to avoidance. These lights can be used as candidates for visual deterrents to reduce collisions with man-made objects and vehicles
Evaluating Blackbird Behavioral Response Toward Unmanned Aircraft Systems (UASs) : Exploiting Antipredator Behavior to Enhance Avoidance
Animals respond to nonlethal forms of human disturbance using behavior strategies adapted to detect, avoid, and evade natural predators. This phenomenon suggests antipredator behavior can be exploited to optimize efficacy of wildlife management tools such as visual deterrents. According to models of antipredator theory, wildlife managers could encourage animals to abandon a resource patch in zones of human-wildlife conflict by enhancing perceived predation risk associated with disturbance stimuli. One human-wildlife conflict of interest is the economic loss and human safety hazards caused by birds. For example, blackbirds (Icteridae) pose a significant risk to the commercial aviation industry through bird strikes and to agriculture through crop predation. Several nonlethal frightening devices have been used in an attempt to reduce negative impacts of large blackbird flocks with varying effectiveness, thus the need for new or optimized tools remains. A promising tool in the field of wildlife damage management is the unmanned aircraft system (UAS), which provides a dynamic object able to overcome mobility limitations faced by other nonlethal deterrents. We intend to evaluate antipredator response of blackbirds toward two UAS platforms. We will compare a multirotor quadcopter UAS with a radiocontrolled (RC) predator model. Current UASs show promise as precision agriculture tools and are easier to fly, but may not elicit an antipredator response due to lack of similarity with natural predators. We hypothesize that blackbirds will assess platforms with different intensities of perceived predation risk, and as a result, initiate flight at farther distances from the platform perceived as more threatening. Our objectives are to 1) compare the response of captive red-winged blackbirds (Agelaius phoeniceus) to a multirotor quadcopter UAS and a RC predator model approaching at direct and overhead trajectories; and 2) approach wild flocks of red-winged blackbirds to gauge response of free-ranging birds toward both UAS platforms. The results of this study will help develop UASs as potential hazing tools to disperse and deter birds from areas of human-wildlife conflict (i.e., airports, agricultural areas, and municipalities)
Species With Greater Aerial Maneuverability Have Higher Frequency of Collisions With Aircraft: A Comparative Study
Antipredator responses may appear unsuccessful when animals are exposed to approaching vehicles, often resulting inmortality. Recent studies have addressed whether certain biological traits are associated with variation in collision risk with cars, but not with higher speed-vehicles like aircraft. Our goal was to establish the association between different species traits (i.e., body mass, eye size, brain size, wing loading, wing aspect ratio) and the frequency of bird collisions with aircraft (hereafter, bird strikes) using a comparative approach controlling for the effects of shared ancestry. We proposed directional predictions as to how each of the species traits would affect the frequency of bird strikes. Considering 39 bird species with all traits represented, the model containing wing loading had the best fit to account for the variance in bird strikes across species. In another model with 54 species exploring the fit to different polynomial models but considering only wing loading, we found that wing loading was negatively and linearly associated with the frequency of bird strikes. Counterintuitively, species with lower wing loading (hence, greater maneuverability) had a higher frequency of bird strikes. We discuss potential non-mutually exclusive explanations (e.g., high wing loading species fly faster, thus gaining some extra time to avoid the aircraft flight path; high wing loading species are hazed more intensively at airports, which could lower collisions, etc.). Ultimately, our findings uncovered that species with low wing loading get struck at a higher rate at airports, which reduces the safety risk for humans because these species tend not to cause damaging strikes, but the ecological consequences of their potentially higher local mortality are unknown
Assessing bird avoidance of high-contrast lights using a choice test approach: implications for reducing human-induced avian mortality
Background: Avian collisions with man-made objects and vehicles (e.g., buildings, cars, airplanes, power lines) have increased recently. Lights have been proposed to alert birds and minimize the chances of collisions, but it is challenging to choose lights that are tuned to the avian eye and can also lead to avoidance given the differences between human and avian vision. We propose a choice test to address this problem by first identifying wavelengths of light that would over-stimulate the retina using species-specific perceptual models and by then assessing the avoidance/attraction responses of brown-headed cowbirds to these lights during daytime using a behavioral assay.
Methods: We used perceptual models to estimate wavelength-specific light emitting diode (LED) lights with high chromatic contrast. The behavioral assay consisted of an arena where the bird moved in a single direction and was forced to make a choice (right/left) using a single-choice design (one side with the light on, the other with the light off) under diurnal light conditions.
Results: First, we identified lights with high saliency from the cowbird visual perspective: LED lights with peaks at 380 nm (ultraviolet), 470 nm (blue), 525 nm (green), 630 nm (red), and broad-spectrum (white) LED lights. Second, we found that cowbirds significantly avoided LED lights with peaks at 470 and 630 nm, but did not avoid or prefer LED lights with peaks at 380 and 525 nm or white lights.
Discussion: The two lights avoided had the highest chromatic contrast but relatively lower levels of achromatic contrast. Our approach can optimize limited resources to narrow down wavelengths of light with high visual saliency for a target species leading to avoidance. These lights can be used as candidates for visual deterrents to reduce collisions with man-made objects and vehicles
Physiology, behavior, and conservation
Many animal populations are in decline as a result of human activity. Conservation practitioners are attempting to prevent further declines and loss of biodiversity as well as to facilitate recovery of endangered species, and they often rely on interdisciplinary approaches to generate conservation solutions. Two recent interfaces in conservation science involve animal behavior (i.e., conservation behavior) and physiology (i.e., conservation physiology). To date, these interfaces have been considered separate entities, but from both pragmatic and biological perspectives, there is merit in better integrating behavior and physiology to address applied conservation problems and to inform resource management. Although there are some institutional, conceptual, methodological, and communication-oriented challenges to integrating behavior and physiology to inform conservation actions, most of these barriers can be overcome. Through outlining several successful examples that integrate these disciplines, we conclude that physiology and behavior can together generate meaningful data to support animal conservation and management actions. Tangentially, applied conservation and management problems can, in turn, also help advance and reinvigorate the fundamental disciplines of animal physiology and behavior by providing advanced natural experiments that challenge traditional frameworks
Näyttöön perustuva tuki- ja liikuntaelinsairauksien kuntoutus
103 s.Kelan rahoittaman TULES- eli tuki- ja liikuntaelinsairauksien kuntoutuksen standardien kehittämistä tukevan tutkimuksen (11/2013–8/2014) yhtenä osatavoitteena oli kartoittaa keskeisin tutkimusnäyttö tuki- ja liikuntaelinsairauksien vaikuttavasta kuntoutuksesta. Tämän työpaperin tarkoitus on antaa kuntoutuksen suunnittelijoille ja käytännön työntekijöille tietoa tämänhetkisen TULES-kuntoutuksen tutkimuksen tuloksista. Järjestelmällinen kirjallisuuskatsaus tuo esille vaikuttavaksi osoitettuja kuntoutusmuotoja. Tähän kirjallisuuskatsaukseen on lisäksi kerätty tietoa eri maiden kuntoutussuosituksista alaselän, niskan, olkapään sekä polven ja lonkan TULE-sairauksien osalta sekä kuntouttavan liikuntaharjoittelun perusteista. Järjestelmällinen tiedonhaku suoritettiin viiden vuoden ajalta; vuoden 2009 alusta vuoden 2013 loppuun saakka. Järjestelmällisen katsauksen päätulokset osoittivat aktiiviseen terapeuttiseen harjoitteluun perustuvien ohjelmien olevan vaikuttavia kaikkien katsauksessa mukana olleiden TULE-sairauksien kuntoutuksessa. Lisäksi todettiin manuaalisen terapian olevan vaikuttavaa alaselän ja niskan kuntoutuksessa. Kohtalaista tutkimusnäyttöä löytyi tiettyjen fysikaalisten hoitojen, mm. akupunktion, laserterapian ja pulsoivan magneettiterapian vaikuttavuudesta jokaisessa tutkitussa TULE-sairaudessa. Ohjauksellisista interventioista ainoastaan behavioraalisen terapian vaikuttavuus on osoitettu kohtalaiseksi alaselän kuntoutuksessa. Eri maiden ja yhdistysten suositukset painottavat tutkimusnäytön mukaisesti aktiivista harjoittelua niin selkä-, niska- kuin nivelkuntoutuksessa
Behavior and Physiology in the Development and Application of Visual Deterrents at Airports
In the first major treatise on the science of wildlife damage management, Conover (2002) dedicated a short review of visual stimuli used to deter wildlife from specific areas or resources. The brevity of the review reflects the fact that these techniques have traditionally been developed over short periods and used to conhont an immediate problem. generally through trial and error. Because humans perceive visual stimuli differently than other animals (Schwab 2012). deterrents based on human perception likely fall short in saliency of the stimuli (Le., how well the stimuli stand out against a background). However, assessment of visual stimuli (both deterrents and cues) in the context of animal sensory physiology and behavior holds promise for the development of novel and more effective methods to mitigate negative human-wildlife interactions