Article

Hearing Range of White-Tailed Deer as Determined by Auditory Brainstem Response

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Abstract

: Basic knowledge of white-tailed deer (Odocoileus virginianus) hearing can improve understanding of deer behavior and may assist in the development of effective deterrent strategies. Using auditory brainstem response testing, we determined that white-tailed deer hear within the range of frequencies we tested, between 0.25–30 kilohertz (kHz), with best sensitivity between 4–8 kHz. The upper limit of human hearing lies at about 20 kHz, whereas we demonstrated that white-tailed deer detected frequencies to at least 30 kHz. This difference suggests that research on the use of ultrasonic (frequencies >20 kHz) auditory deterrents is justified as a possible means of reducing deer—human conflicts.

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... When vehicles reach speeds >48 km/hr the whistle sounds. Studies have found that deer hearing is most sensitive in the range of 2–6 kHz (Scheifele et al. 2003) or 4–8 kHz (D'Angelo et al. 2007). Tested whistles, however, emitt ed frequencies both inside (3 kHz) and outside (12 kHz) these hearing ranges (Scheifele et al. 2003). ...
... Tested whistles, however, emitt ed frequencies both inside (3 kHz) and outside (12 kHz) these hearing ranges (Scheifele et al. 2003). D'Angelo et al. (2007) calculated that under ideal conditions, a whistle would need to emit 100 dB sound pressure level at 1 m to be heard 100 m from a vehicle. However, whether this distance would allow deer to avoid being hit by a vehicle is unknown (D'Angelo et al. 2007). ...
... D'Angelo et al. (2007) calculated that under ideal conditions, a whistle would need to emit 100 dB sound pressure level at 1 m to be heard 100 m from a vehicle. However, whether this distance would allow deer to avoid being hit by a vehicle is unknown (D'Angelo et al. 2007). This conclusion was corroborated by Romin and Dalton (1992) who found that the reactions of deer to vehicles equipped with whistles and to those without them were similar. ...
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Every year in the United States approximately 1.5 million deer-vehicle collisions (DVCs) occur resulting in >29,000 human injuries, >200 human fatalities, 1.3 million deer fatalities, and >1 billion dollars worth of property damage. Despite the magnitude of this problem, there are relatively few well-designed studies that have evaluated techniques that can be used to reduce DVCs. Techniques to reduce DVCs fall into 4 categories: reducing the number of deer (Odocoileus spp.), reducing the number of vehicles, modifying deer behavior, and changing motorist behavior. Techniques to reduce the number of deer include decreasing the deer population or excluding deer from the roadway. Techniques used to change motorist behavior include reducing vehicle speed or increasing motorists' ability to see deer. Modifying deer behavior includes making the roadside less attractive to deer or frightening deer away from the roadway. Despite a limited amount of data, multiple studies have shown properly installed and maintained fences combined with wildlife crossings to be the most effective method of reducing DVCs. Methods with unproven effectiveness include: intercept feeding, repellents, reduced speed limits, caution signs, and roadway lighting. Stimuli designed to frighten deer (e.g., deer whistles, fl agging, and deer refl ectors) are ineffective because they cannot be perceived by deer or do not elicit a fl ight response. Well-designed studies are needed so that we can acquire the knowledge about how to reduce the frequency of DVCs.
... The effect of noise on wild animals was investigated by many researchers and these problems are described, for example, in references [35][36][37]. Focusing on the most common species of wild animals, the authors studied the effects of road noise on the hearing ranges of roe deer (Capreolus capreolus) [38,39] and red deer (Cervus elaphus) [40,41] and the distances of individual noise ranges from the road [42,43]. However, the results of the studies were related more to the determination of the sensitivity of wild animals to road noise and selection of appropriate deterrent devices during the time when a given location was passed by a car [44][45][46]. ...
... From among these animals, roe deer (Capreolus capreolus) and fallow deer (Dama dama) are the primary users of the wildlife overpasses located in rural areas. Taking this into consideration, the hearing ranges of roe deer (Capreolus capreolus), given in various publications, were analysed [39][40][41]. The main studies, presented in [44][45][46], concerned the reaction of animals to various sounds emitted by the deterrents mounted on the road or on the vehicles. ...
... The main studies, presented in [44][45][46], concerned the reaction of animals to various sounds emitted by the deterrents mounted on the road or on the vehicles. The publications [38,39] stated that deer (Capreolus) had the greatest hearing sensitivity between 1 and 8 kHz, with a peak sensitivity at 4 kHz and a range from 0.5 to 12 kHz (at 85 dB(A)). According to a similar study, white-tailed deer (Capreolus) were able to hear in the range of 0.25 to 30 kHz, with a peak sensitivity between 4 and 8 kHz [38,46]. ...
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The constantly growing number of motor vehicles increases the biodiversity conservation awareness of the public. To this end, numerous compensation measures are implemented, primarily provision of wildlife crossing infrastructure to guide animals over and under transport routes. There are different design aspects that must be considered in the case of wildlife crossings located in rural areas and in forests. An interdisciplinary approach should be employed for the wildlife crossing design, involving specialists from different fields of science. This article deals with the effect of local landscape elements and structures on the acoustic environment on the wildlife overpasses located in rural areas. Several tests were carried out, covering the levels of traffic, improvements around the existing overpasses and the noise distribution on them. For the final analysis, seven overpasses were chosen, differing in terms of the landscape elements and structures present. Five of them included noise barriers of different shapes and lengths and had a flat approach area. Two crossings did not have noise barriers and the approach areas were located in varied terrain. The analysis of the derived sound maps allowed for the determination of the effect of the different landscape elements and structures on the noise distribution on the overpasses under analysis. Earthen berms aligned with the noise barriers and extending to the length defined by the approach area topography were found to be the most effective noise-reducing measure.
... Where exclusion techniques are not used, harassment of deer using loud noises and flashing lights should be used sparingly to keep deer from runways (Craven and Hygnstrom 1994) before take-offs and landings. Sound deterrents operating at 4-8 kHz are most effective (D'Angelo et al. 2007). However, deer may be deterred with sounds from 20 kHz to 30 kHz, above human hearing, which would reduce negative experiences for airport personnel and travelers (D'Angelo et al. 2007). ...
... Sound deterrents operating at 4-8 kHz are most effective (D'Angelo et al. 2007). However, deer may be deterred with sounds from 20 kHz to 30 kHz, above human hearing, which would reduce negative experiences for airport personnel and travelers (D'Angelo et al. 2007). Increasing deer visibility by installing additional or unconventional lighting should also be considered. ...
Article
Aircraft incidents with ungulates cause substantial economic losses and pose risks to human safety. We analyzed 879 white-tailed deer (Odocoileus virginianus) incidents with United States civil aircraft from 1990 to 2009 reported in the Federal Aviation Administration National Wildlife Strike Database. During that time, deer incidents followed a quadratic response curve, peaking in 1994 and declining thereafter. There appeared to be some seasonal patterning in incident frequency, with deer incidents increasing overall from January to November, and peaking in October and November (30.7%). Most incidents (64.8%) occurred at night, but incident rates were greatest (P ≤ 0.001) at dusk. Landing-roll represented 60.7% of incidents and more incidents occurred during landing than take-off (P ≤ 0.001). Almost 70% of deer incidents had an effect on flight. About 6% of pilots attempted to avoid deer, and were less likely to sustain damage. Aircraft were 25 times more likely to be destroyed when multiple deer were struck versus a single individual. Deer incidents represented 0.9% of all wildlife incidents, yet 5.4% of total estimated costs. Reported costs for deer incident damages during this period exceeded US$36 million, with US$75 million in total estimated damages. Deer incidents resulted in 1 of 24 human deaths and 26 of 217 injuries reported for all wildlife incidents with aircraft during the reporting period. Managers should implement exclusion techniques (e.g., fences, cattle guards, or electrified mats) to maximize reductions in deer use of airfields. Where exclusion is not practical, managers should consider lethal control, habitat modifications, increased monitoring and hazing, and improved technology to aircraft and runway lighting to reduce incidents at airports. © 2011 The Wildlife Society.
... Because deer are naturally afraid of humans and do not readily tolerate our presence, it is difficult to conduct behavioral tests on them. As a result, the only measure of their hearing currently available is their auditory brainstem response (D'Angelo et al., 2007). This measurement indicates that the hearing range of deer extends from 250 Hz to 30 kHz, with a best sensitivity of only 42 dB at 4 and 8 kHz. ...
Article
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The behavioral audiograms of two female white-tailed deer (Odocoileus virginianus) were determined using a conditioned-suppression avoidance procedure. At a level of 60 dB sound pressure level, their hearing range extends from 115 Hz to 54 kHz with a best sensitivity of -3 dB at 8 kHz; increasing the intensity of the sound extends their hearing range from 32 Hz (at 96.5 dB) to 64 kHz (at 93 dB). Compared with humans, white-tailed deer have better high-frequency but poorer low-frequency hearing. (C) 2010 Acoustical Society of America
... Various scientific studies have focused on strategies to minimize deer-vehicle collisions (DVCs) and to reduce damage to cultivated plants (VerCauteren et al. , 2006Blackwell and Seamans 2008). However, despite some understanding about white-tailed deer visual and auditory physiology (Jacobs et al. 1994;D'Angelo et al. 2007D'Angelo et al. , 2008, little research has confirmed how deer perceive their environment through sight and sound (Zacks and Budde 1983, Zacks 1985, Birgersson et al. 2001, Heffner and Heffner 2010. Even then, interpretation of these studies is difficult due to small sample size and the cognition systems of animals (Jacobs 1993, VerCauteren and. ...
Article
Although many aspects of white-tailed deer (Odocoileus virginianus) biology and physiology have been studied thoroughly, few studies have confirmed deer cognitive perception, partly because of the difficulty of efficiently training sufficient numbers of deer to respond behaviorally in controlled experiments. We present a system that trains white-tailed deer to associate a supra-threshold, white-light stimulus with a food reward through operant conditioning techniques. The “deer training apparatus” (DTA) automatically dispenses food, rings a start buzzer, randomly assigns a stimulus light over 1 of 2 troughs, and registers a deer's choice. If a deer goes to a trough with the light illuminated, then a correct choice is registered. All 6 deer tested met successful training criteria by Day 19, and a performance of 88.2% ± 3.9% correct choices by Day 25. We conclude that the DTA presents an effective and efficient way of training white-tailed deer, and provides an experimental platform for future research on behavior, perception, and preference. Thus, the DTA should be useful to researchers evaluating behavioral response of deer, and possibly other wild and domestic species, to various visual and auditory stimuli. © 2012 The Wildlife Society.
... In order for any acoustic-based repellent to potentially have an effect, the animal must be capable of hearing and responding to that sound. Using various methodologies, the hearing of white-tailed deer has been reported to range from 0.115 kHz to 54 kHz with greatest sensitivities in the 4-8 kHz region (D'Angelo et al. 2007, Heffner and Heffner 2010, Biondi et al. 2011. ...
... We specifically selected the microphone because of its ability to capture all sound frequencies between 20 and 20 000 Hz. These frequencies overlap the range of frequencies white-tailed deer are most sensitive to (4000-8000 Hz) and cover most of their detectable spectrum (0.25-30 000 Hz) (D'Angelo et al. 2007). We recorded the noise for four 1 h-periods over the course of a two-day period when wind speed was below 4 on the Beaufort wind scale (Supplementary material Appendix 1). ...
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... Auditory evoked potentials have been widely used to study hearing and sound communication in a broad diversity of non-human vertebrates, including mammals (Walsh et al. 1986;Katbamna et al. 1992;Supin et al. 1993;Aitkin et al. 1996;McFadden et al. 1996;Uetake et al. 1996;Uzuka et al. 1996;Szymanski et al. 1998;Popov and Supin 2001;Song et al. 2006;D'Angelo et al. 2007;Nachtigall et al. 2007;Nachtigall and Supin 2008;Ramsier and Dominy 2010), birds , 2005Brittan-Powell and Dooling 2004;Lucas et al. 2002;Henry and Lucas 2008Caras et al. 2010;Gall et al. 2011;Noirot et al. 2011;Lohr et al. 2013), reptiles (Bartol et al. 1999;Higgs et al. 2002;Brittan-Powell et al. 2010b;Martin et al. 2012), and fish (Kenyon et al. 1998;Ladich and Yan 1998;Ladich 2001, 2003;Lugli et al. 2003;Smith et al. 2004;Amoser and Ladich 2005;Horodysky et al. 2008), as well as a few invertebrates (Lovell et al. 2005;Hu et al. 2009;Mooney et al. 2010). While a few previous studies used AEPs to investigate the auditory systems of frogs, these studies used invasive recording procedures requiring surgery (Corwin et al. 1982;Hillery 1984a;Seaman 1991;Carey and Zelick 1993;Bibikov and Elepfandt 2005;Katbamna et al. 2006b;Yu et al. 2006). ...
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Our knowledge of the hearing abilities of frogs and toads is largely defined by work with a few well-studied species. One way to further advance comparative work on anuran hearing would be greater use of minimally invasive electrophysiological measures, such as the auditory brainstem response (ABR). This study used the ABR evoked by tones and clicks to investigate hearing in Cope's gray treefrog (Hyla chrysoscelis). The objectives were to characterize the effects of sound frequency, sound pressure level, and subject sex and body size on ABRs. The ABR in gray treefrogs bore striking resemblance to ABRs measured in other animals. As stimulus level increased, ABR amplitude increased and latency decreased, and for responses to tones, these effects depended on stimulus frequency. Frequency-dependent differences in ABRs were correlated with expected differences in the tuning of two sensory end organs in the anuran inner ear (the amphibian and basilar papillae). The ABR audiogram indicated two frequency regions of increased sensitivity corresponding to the expected tuning of the two papillae. Overall, there was no effect of subject size and only small effects related to subject sex. Together, these results indicate the ABR is an effective method to study audition in anurans.
... Live traps or lethal traps can be used to capture medium-sized mammals (i.e., canids, raccoons, and woodchucks) (Cleary and Dolbeer 2005). Loud noises, from 4 to 8 kHz or 20-30 kHz for deer (D'Angelo et al. 2007), or lights may be effective at repelling mammals (Craven and Hyngstrom 1994; Cleary and Dolbeer 2005;Blackwell and Seamans 2009). Propane cannons or pyrotechnics may repel mammals temporarily but cannot be used long term because individuals habituate to the explosions (Belant et al. 1996;Cleary and Dolbeer 2005). ...
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Thesis
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To assess the accuracy of threshold estimates determined using the auditory brain stem responses (ABRs) to brief tones presented in notched noise in a group of infants and young children with normal hearing or sensorineural hearing loss (SNHL). The thresholds for ABRs to brief duration 500, 2000, and 4000 Hz tones presented in notched-noise masking were evaluated in infants and young children with normal hearing (N = 34) or SNHL (N = 54). Tone-evoked ABR thresholds were compared with behavioral thresholds obtained at follow-up audiologic assessments, for a total of 220 comparisons. ABR thresholds for the infants with bilateral normal hearing were 23.6, 12.9, and 12.6 dB nHL for 500, 2000 and 4000 Hz, respectively. Most (92 to 100%) infants with normal hearing showed ABRs to 30 dB nHL tones. Across all subjects (i.e., those with normal hearing and those with impaired hearing), high ( > or = 0.94) correlations were found between the ABR and behavioral thresholds. The mean differences between ABR (dB nHL) and behavioral (dB HL) thresholds across all subjects were 8.6, -0.4, and -4.3 dB for 500, 2000, and 4000 Hz, respectively. Overall, 98% of the ABR thresholds were within 30 dB of the behavioral thresholds, 93% were within 20 dB, and 80% were within 15 dB. These threshold results for the ABR to brief tones in notched noise obtained for infants and young children are similar to those obtained in similar studies of adults. The technique may be used clinically with reasonable accuracy to estimate pure-tone behavioral thresholds in infants and young children who are referred for diagnostic threshold ABR testing.
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Twelve different white-tailed deer (Odocoileus virginianus) vocalizations were recorded. Ten of these were analyzed with a sound spectrograph. Alarm calls consisted of the snort, given when a deer detected danger, and a bawl, given when a deer was traumatized. Three agonistic calls were recorded. The low grunt was given in low-level agonistic interactions. The grunt-snort, given during more intense dominance interactions, consisted of the low grunt with 1-4 rapid snorts added. The grunt-snort-wheeze consisted of the grunt-snort with the addition of a wheezing exhalation through the nostrils. It was characteristic of dominance interactions among bucks during the breeding season. Four maternal-neonatal sounds were recorded. The maternal grunt was used by does searching for their bedded fawns. The mew was given by fawns and appeared to solicit care from the mother. The bleat was a more insistent care solicitation call and was given when fawns were disturbed or deprived. A nursing whine was given repeatedly while suckling. Mating calls consisted of a tending grunt and the flehmen-sniff. When separated from members of their group, females gave a contact call.
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The ROO-Guard® is an ultrasonic device designed to protect agricultural properties from kangaroos (Macropus spp.). The manufacturer claims that the signal produced by the ROO-Guard covers a 250-m area, is audible to kangaroos, and results in kangaroos leaving the area. I conducted laboratory and field trials to evaluate these claims. Laboratory trials showed that the ROO-Guard signal had only a small component of ultrasonic frequencies and could be detected using an SPL meter at 70 dB at 50 m. The ROO-Guard did not alter the behavior of captive eastern gray kangaroos (M. giganteus) or red kangaroos (M. rufus) in any way. The ROO-Guard alone did not reduce the density of free-ranging eastern gray kangaroos at sites where the device was operating as compared to control sites, and I found no change in density with distance from the device. The ineffectiveness of the ROO-Guard should caution against using other ultrasonic deterrent devices, particularly for kangaroos.
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Auditory brainstem responses were recorded from 20 normally hearing subjects using tone-burst stimuli that were gated with cosine-squared functions. Clear responses were observed over a wide range of frequencies and levels. These responses were highly reproducible within individual subjects and were reliably measured by two independent examiners. ABR thresholds were higher than behavioral thresholds for all frequencies, especially for lower frequencies. Intersubject variability also was greater for lower frequencies. Wave-V latencies decreased with increases in both frequency and level for frequencies from 250 to 8000 Hz and for levels from 20 to 100 dB SPL. The standard deviations seldom exceeded 10% of the mean wave-V latency for any combination of level and frequency. These latencies can be viewed as the sum of both a peripheral and a central component. Assuming that the central component is relatively independent of both frequency and level, changes of wave V latency must be related to peripheral factors, such as travel time along the cochlear partition, and to stimulus characteristics, such as rise time.
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ABR and behavioral thresholds were estimated as a function of stimulus duration for three normal and two hearing-impaired subjects. Stimuli were 2000-Hz tone bursts with 0.5-ms rise/fall times and durations ranging from 1 to 256 or 512 ms. For both groups of subjects, ABR thresholds were independent of stimulus duration. Normal subjects showed greater improvement in behavioral thresholds as a function of duration than did subjects with hearing losses. Thus, it appeared that ABR and behavioral thresholds were affected differently by changes in stimulus duration and that the magnitude of these differences could depend upon the presence of hearing loss. These data indicate that temporal integration may be one factor which makes comparisons between ABR and behavioral thresholds complicated. In the present study, the magnitude of hearing loss, measured by the ABR, would have been underestimated if normal behavioral thresholds for short-duration stimuli were used as the reference.
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The audiogram of two yearling male reindeer (Rangifer tarandus tarandus) were determined using a conditioned suppression/avoidance procedure. During testing, the animal was drinking from a metal bowl while pure tone signals were played at random intervals and followed by an electric shock in the bowl. By breaking contact with the bowl at sound signals, the animal avoided the shock. The animals detected sounds at intensities of 60 dB or less from 70 Hz to 38 kHz. The frequency range of best sensitivity was relatively flat from 1 kHz to 16 kHz, with a best sensitivity of 3 dB at 8 kHz. The hearing ability of reindeer is similar to the hearing ability of other ungulates.
Baseline ABRs in mountain sheep and desert mule deer
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Audio engineer's reference book Analysis and effectiveness of deer whistles for motor vehicles: frequencies, levels, and animal threshold responses
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U.S. Department of Labor, Washington, D.C., USA. Ratcliff, J. 1999. Mathematics, formulae and equations. Pages 2–10 in M. T. Smith, editor. Audio engineer's reference book. Focal Press, Woburn, Massachusetts, USA. Scheifele, P. M., D. G. Browning, and L. M. Collins-Scheifele. 2003. Analysis and effectiveness of deer whistles for motor vehicles: frequencies, levels, and animal threshold responses. Acoustics Research Letters Online 4:71–76.
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Effects of military operations on behavior and hearing of endangered Sonoran pronghorn
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