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In the California Current off the United States West Coast, there are three offshore cetacean species that produce narrow-band high frequency (NBHF) echolocation pulses: Dall's porpoise (Phocoenoides dalli) and two species of Kogia. NBHF pulses exist in a highly specialized acoustic niche thought to be outside the hearing range of killer whales and other potential mammal-eating odontocetes. Very little is known about the dwarf and pygmy sperm whales (K. sima and K. breviceps), including their NBHF pulse characteristics. This paper presents a multivariate clustering method using data from unmanned drifting acoustic recorders and visually verified porpoise recordings to discriminate between probable porpoise and Kogia clicks. Using density clustering, this study finds three distinct clusters whose geographic distributions are consistent with the known habitat range for Kogia and Dall's porpoise. A Random Forest classification model correctly assigned 97% of the clicks to their cluster. Visually verified Dall's porpoise clicks from towed hydrophones were strongly associated with one of the clusters, while a second cluster tended to be outside the geographic range of Dall's porpoise and unlike the Dall's porpoise cluster. These clicks, presumed to be made by Kogia, exhibited greater spectral variance than previous Kogia echolocation studies. It is possible that the structure of Kogia NBHF pulses may not be as stereotypical as previously described.

A maximum likelihood method is presented for estimating drift direction and speed of a directional sonobuoy given the deployment location and a time series of acoustic bearings to a sound source at known position. The viability of this method is demonstrated by applying it to two real-world scenarios: (1) during a calibration trial where buoys were independently tracked via satellite, and (2) by applying the technique to sonobuoy recordings of a vocalising Antarctic blue whale that was simultaneously tracked by photogrammetric methods. In both test cases, correcting for sonobuoy drift substantially increased the accuracy of acoustic locations.

During dedicated surveys for the Critically Endangered eastern stock of North Pacific right whales Eubalaena japonica (NPRW) in the Bering Sea, focal follows (FFs) were combined with passive acoustic monitoring to correlate vocal activity with dive behavior. During FFs, impulsive gunshot calls (hereafter ‘gunshots’), similar to those produced by other right whale populations, were localized to male and female NPRWs. The timing of gunshots correlated strongly with diving behavior observed during the FFs. Log survivorship analysis of inter-blow intervals showed a bout criterion interval of 40 s, separating the data into shorter surfacings and longer dives. For both, gunshots were skewed closer to the end of the sequence (modal gunshot to blow times: 5 s for dives, 7 s for surfacings) than the beginning (modal blow to gunshot times: 22 s for dives, 13 s for surfacings). Gunshots were more commonly produced during dives than surfacings. Mean gunshot calling rate during FFs was 133.0 calls h-1 (range: 38.9-425.0). Other NPRW calls, including upcalls, the predominant call used to identify right whales acoustically, were not detected during the FFs. To determine comparative call detection rates, an additional 180 h of non-FF recordings were analyzed. Gunshots were detected ~50 times more frequently than upcalls (mean: 228.3 vs. 4.3 calls h-1, respectively), with a maximum gunshot calling rate of 835.7 calls h-1. This is the first study to definitively attribute gunshots to NPRW, and demonstrates the importance of including gunshots in passive acoustic studies, which will greatly increase NPRW detectability while supporting more accurate determinations of their spatio-temporal distribution.

Passive acoustic monitoring of dolphins is limited by our ability to classify calls to species. Significant overlap in call characteristics among many species, combined with a wide range of call types and acoustic behavior, makes classification of calls to species challenging. Here, we introduce BANTER, a compound acoustic classification method for dolphins that utilizes information from all call types produced by dolphins rather than a single call type, as has been typical for acoustic classifiers. Output from the passive acoustic monitoring software, PAMGuard, was used to create independent classifiers for whistles, echolocation clicks, and burst pulses, which were then merged into a final, compound classifier for each species. Classifiers for five species found in the California Current ecosystem were trained and tested using 153 single-species acoustic events recorded during a 4.5 mo combined visual and acoustic shipboard cetacean survey off the west coast of the United States. Correct classification scores for individual species ranged from 71% to 92%, with an overall correct classification score of 84% for all five species. The conceptual framework of this approach easily lends itself to other species and study areas as well as to noncetacean taxa.

Hearing sensitivity is a fundamental determinant of a species’ vulnerability to anthropogenic noise, however little is known about the hearing capacities of most conservation dependent species. When audiometric data are integrated with other aspects of species’ acoustic ecology, life history, and characteristic habitat topography and soundscape, predictions can be made regarding probable vulnerability to the negative impacts of different types of anthropogenic noise. Here we used an adaptive psychoacoustic technique to measure hearing thresholds in the endangered giant panda; a species that uses acoustic communication to coordinate reproduction. Our results suggest that giant pandas have functional hearing into the ultrasonic range, with good sensitivity between 10.0 and 16.0 kHz, and best sensitivity measured at 12.5–14.0 kHz. We estimated the lower and upper limits of functional hearing as 0.10 and 70.0 kHz respectively. While these results suggest that panda hearing is similar to that of some other terrestrial carnivores, panda hearing thresholds above 14.0 kHz were significantly lower (i.e., more sensitive) than those of the polar bear, the only other bear species for which data are available. We discuss the implications of this divergence, as well as the relationship between hearing sensitivity and the spectral parameters of panda vocalizations. We suggest that these data, placed in context, can be used towards the development of a sensory-based model of noise disturbance for the species.

There is a 6.4 percent incidence of rubella exposure during pregnancy in the U.S. Given the severe effects rubella can have on a developing fetus, vaccination of women prior to pregnancy is important. Women seeking fertility treatment therefore present a population of patients primed for the vaccination. This study collected and analyzed rubella-specific immunoglobulin G (RV-IgG) titer statuses and corresponding demographics of infertility patients to identify patients at risk of rubella nonimmunity.The study consisted of a retrospective review of electronic medial records (EMR) of female patients, ages 18 to 50, who were new patients receiving an infertility workup at a Midwestern reproductive endocrinology clinic from Jan. 1, 2010 through Dec. 31, 2014. Of those patients who had RV-IgG titers noted in their EMR, the following demographics were collected: age, race, gravidity and parity, state of residence, and community size.There were 750 patients included in the study. Rubella titers were drawn on 72.7 percent of the patients. Of those drawn, 90.8 percent had a positive rubella titer. Most of the participants (92.3 percent) were identified as Caucasian/White. Caucasians/Whites, Asians, and African Americans/Blacks had the highest rates of rubella immunity, while American Indians/Alaskan Natives had the lowest rates of immunity (p=0.0006). Nulligravida participants had a positive rubella titer rate of 94.1 percent, while primigravida participants had a rate of 89.8 percent (p=0.04). Participants living in the largest sampled communities had the lowest rates of positive rubella titers, while those living in the smallest communities had the highest rates of positive rubella titers, although these findings were not statistically significant.Of the infertility patients, 27.3 percent did not have an RV-IgG titer drawn as part of their fertility workup. Of the 72.7 percent of patients for whom titers were checked, nearly 10 percent were not immune to rubella. While there are a couple reasons why a patient may not have a positive titer, lack of immunization is the most common reason. Data analysis identified significance in the difference in titer status only with respect to race and gravidity, and those findings, particularly race, must be viewed critically in light of the study population. While the statistical significance of the study may be limited, there is clinical significance in identifying infertility patients at highest risk of rubella nonimmunity so vaccination education and efforts can be focused accordingly.

Although mammal vocalisations signal attributes about the caller that are important in a range of contexts, relatively few studies have investigated the transmission of specific types of information encoded in mammal calls. In this study we broadcast and re-recorded giant panda bleats in a bamboo plantation, to assess the stability of individuality and sex differences in these calls over distance, and determine how the acoustic structure of giant panda bleats degrades in this species’ typical environment. Our results indicate that vocal recognition of the caller’s identity and sex is not likely to be possible when the distance between the vocaliser and receiver exceeds 20 m and 10 m, respectively. Further analysis revealed that the F0 contour of bleats was subject to high structural degradation as it propagated through the bamboo canopy, making the measurement of mean F0 and F0 modulation characteristics highly unreliable at distances exceeding 10 m. The most stable acoustic features of bleats in the bamboo forest environment (lowest % variation) were the upper formants and overall formant spacing. The analysis of amplitude attenuation revealed that the fifth and sixth formant are more prone to decay than the other frequency components of bleats, however, the fifth formant still remained the most prominent and persistent frequency component over distance. Paired with previous studies, these results show that giant panda bleats have the potential to signal the caller’s identity at distances of up to 20 m and reliably transmit sex differences up to 10 m from the caller, and suggest that information encoded by F0 modulation in bleats could only be functionally relevant during close-range interactions in this species’ natural environment.

Though odontocete echolocation clicks are highly useful in passive acoustic monitoring, their acoustic features vary depending on behavior, orientation, and location relative to the receiver. Using unsupervised machine learning, regional sets of echolocation click types can be identified that allow for automated labeling of bioacoustic data while accounting for within-type signal variability. This methodology derives labels for clusters of click types based on parameters including spectral shape, inter-click interval, and click duration. Here we present classification results of echolocation clicks produced by Hawaiian odontocetes. Unsupervised methods were used to establish a set of click types for 10 years of recordings (200 kHz) collected from a bottom-mounted hydrophone off the coast of Kona, HI. These automated labels were compared with manual labels for species with established and recognizable clicks, which allowed for ground-truthing of some click types identified by the unsupervised machine learning method. Towed array data (500 kHz) was used to assign click types to species with visual verification, expanding the set of known species-specific click types for the region. The click types and method established here will be useful in future analyses of Hawaiian odontocete density estimation, abundance, and distribution patterns using acoustic data without requiring visual confirmation.Though odontocete echolocation clicks are highly useful in passive acoustic monitoring, their acoustic features vary depending on behavior, orientation, and location relative to the receiver. Using unsupervised machine learning, regional sets of echolocation click types can be identified that allow for automated labeling of bioacoustic data while accounting for within-type signal variability. This methodology derives labels for clusters of click types based on parameters including spectral shape, inter-click interval, and click duration. Here we present classification results of echolocation clicks produced by Hawaiian odontocetes. Unsupervised methods were used to establish a set of click types for 10 years of recordings (200 kHz) collected from a bottom-mounted hydrophone off the coast of Kona, HI. These automated labels were compared with manual labels for species with established and recognizable clicks, which allowed for ground-truthing of some click types identified by the unsupervised machine learn...

Echolocation signals produced by beaked whales (family: Ziphiidae) include frequency-modulated (FM) pulses that appear to have species-specific characteristics. To date there has been no established evidence that a single species of beaked whale might produce more than one type of FM pulse. In 2014 a group of Blainville's beaked whales (Mesoplodon densirostris) were sighted off of Southern California; recordings included FM pulses with significant increases in peak frequency, center frequency, and -10 dB bandwidth relative to FM pulses previously attributed to this species. This research suggests there may be greater variation in received beaked whale FM pulses than previously understood.

Little is known about the potential of non-human mammal vocalizations to signal information on the hormonal status of the caller. In the current study, we used endocrine data and acoustic analyses to determine whether male giant panda bleats provide reliable information about the caller's current androgen levels. Our results revealed significant relationships between acoustic features of male giant panda bleats and the caller's faecal androgen metabolite concentrations. To our knowledge, this constitutes the first demonstration that the acoustic structure of a non-human mammal call has the potential to yield information about the caller's current androgen levels. We go on to discuss the anatomical basis for our findings and the potential functional relevance of signalling information on male androgen levels in giant panda sexual communication.

Although female mammal vocal behaviour is known to advertise fertility, to date, no non-human mammal study has shown that the acoustic structure of female calls varies significantly around their fertile period. Here, we used a combination of hormone measurements and acoustic analyses to determine whether female giant panda chirps have the potential to signal the caller's precise oestrous stage (fertile versus pre-fertile). We then used playback experiments to examine the response of male giant pandas to female chirps produced during fertile versus pre-fertile phases of the caller's reproductive cycle. Our results show that the acoustic structure of female giant panda chirps differs between fertile and pre-fertile callers and that male giant pandas can perceive differences in female chirps that allow them to determine the exact timing of the female's fertile phase. These findings indicate that male giant pandas could use vocal cues to preferentially associate and copulate with females at the optimum time for insemination and reveal the likely importance of female vocal signals for coordinating reproductive efforts in this critically endangered species.

Although the acoustic structure of mammal vocal signals often varies according to the social context of emission, relatively few mammal studies have examined acoustic variation during intersexual advertisement. In the current study male giant panda bleats were recorded during the breeding season in three behavioural contexts: vocalising alone, during vocal interactions with females outside of peak oestrus, and during vocal interactions with peak-oestrous females. Male bleats produced during vocal interactions with peak-oestrous females were longer in duration and had higher mean fundamental frequency than those produced when males were either involved in a vocal interaction with a female outside of peak oestrus or vocalising alone. In addition, males produced bleats with higher rates of fundamental frequency modulation when they were vocalising alone than when they were interacting with females. These results show that acoustic features of male giant panda bleats have the potential to signal the caller's motivational state, and suggest that males increase the rate of fundamental frequency modulation in bleats when they are alone to maximally broadcast their quality and promote close-range contact with receptive females during the breeding season.

The DEMMI (de Morton Mobility Index) is a new and advanced instrument for measuring the mobility of all older adults across clinical settings. It overcomes practical and clinimetric limitations of existing mobility instruments. This study reports the process of item reduction using the Rasch model in the development of the DEMMI. Prior to this study, qualitative methods were employed to generate a pool of 51 items for potential inclusion in the DEMMI. The aim of this study was to reduce the item set to a unidimensional subset of items that ranged across the mobility spectrum from bed bound to high levels of independent mobility. Fifty-one physical performance mobility items were tested in a sample of older acute medical patients. A total of 215 mobility assessments were performed. Seventeen mobility items that spanned the mobility spectrum were selected for inclusion in the new instrument. The 17 item scale fitted the Rasch model. Items operated consistently across the mobility spectrum regardless of patient age, gender, cognition, primary language or time of administration during hospitalisation. Using the Rasch model, an interval level scoring system was developed with a score range of 0 to 100.

This study describes the refinement and validation of the 17-item DEMMI in an independent sample of older acute medical patients. Instrument refinement was based on Rasch analysis and input from clinicians and researchers. The refined DEMMI was tested on 106 older general medical patients and a total of 312 mobility assessments were conducted. Based on the results of this study a further 2 items were removed and the 15 item DEMMI was adopted. The Rasch measurement properties of the DEMMI were consistent with estimates obtained from the instrument development sample. No differential item functioning was identified and an interval level scoring system was established. The DEMMI is the first mobility instrument for older people to be developed, refined and validated using the Rasch model. This study confirms that the DEMMI provides clinicians and researchers with a unidimensional instrument for measuring and monitoring changes in mobility of hospitalised older acute medical patients.

This paper describes the development, methods and results of a novel interprofessional student-led aged care clinic. The clinic was established to facilitate the interprofessional education of students approaching graduation in dietetics, medicine, nursing, occupational therapy, pharmacy, physiotherapy, podiatry, social work, and speech pathology. Students worked together in a primary care clinic established to support patients70 years old who had recently been discharged home from an acute hospital admission. The students completed a screening interview of patients in mixed-discipline teams, established health care needs, and wrote referrals for appropriate support services. A mixed-methods evaluation approach was taken; the effects of the clinic on students (n=70) and educators (n=14) were evaluated. A subgroup of students (n=42) and educators (n=12) participated in focus groups designed to enable evaluation of learning outcomes. Students reported developing an expanded perspective of issues that affect the health of older people, felt that they gained knowledge about the practical roles and referral pathways of other disciplines, and described enhanced interprofessional communication skills. Educators reported that they observed the students' development of communication and referral skills and expanded awareness of health domains that they would not previously have considered.

We used behavioral techniques to assess the hearing sensitivity of four, critically endangered, giant pandas at the San Diego Zoo. Study subjects included one adult male (age 19), two adult females (ages 5 and 19), and one sub-adult female (age 3). We used a down-up staircase presentation order and a go/no-go response paradigm and thus far have measured hearing thresholds between 250 Hz and 31.5 kHz. Test stimuli were 500 ms shaped tones, and catch trials represented 30% of presentations. All subjects were trained using positive reinforcement. Preliminary results suggest that giant pandas have good hearing sensitivity between 8 and 14 kHz, and best sensitivity was centered at 12.5 kHz. Low frequency hearing sensitivity declined at 250 Hz for all subjects. All bears retained functional hearing at 31.5 kHz: the younger females could hear tones as low as 15 dB, and the adults could hear to 25 dB. Preliminary results suggest that panda hearing sensitivity is similar to that of other terrestrial carnivores stu...

Silent most of the year, giant pandas (Ailuropoda melanoleuca) engage in sustained and diverse vocal behavior during their brief annual reproductive window. These vocalizations suggest a complex communication repertoire and play an important role in facilitation of mating. To increase our understanding of their vocal communication, we analyzed male and female vocalizations during breeding interactions. Digital audio recordings were collected during breeding seasons of 2008, 2009, and 2011 at zoological facilities in San Diego, California, and China, and were processed using Soundtrack Pro 2.0 and Raven Pro 1.4 software. Seven types of vocalizations were identified (“bark,” “moan,” “growl,” “squeal,” “chirp,” “bleat,” and “copulation call”). We compared vocalizations from 32 confirmed copulations and 37 non-copulatory breeding sessions of 31 individuals (24 females, 7 males). They revealed differences in vocalizations produced before, during, and after intromission. During intromission, the male produces a copulation call that distinguishes successful breeding encounters from unsuccessful pairings acoustically. This call has not been described previously. The results shed light on the motivational and functional significance of panda vocalizations during mating encounters. They can be used in captive breeding programs to promote reproduction in this endangered species. [Work supported by ZSSD, CSUSM, and CCRCGP.]

The eastern population of the North Pacific right whale (Eubalaena japonica) is critically endangered. Following extensive historical whaling in the 19th century and large illegal catches by the USSR in the 1960’s, it is likely that this population now numbers in the tens of animals. Little is known about the distribution, movements, migrations, or habitat use of this population, but the existing data suggest that it now occupies a reduced range compared to historical times. In 2007, NMML began conducting a multiyear study of the distribution, abundance, and habitat use of North Pacific right whales in the North Aleutian Basin and southeastern Bering Sea using aerial and vessel surveys. During the 2008 survey, directional sonobuoys were used 24 h a day to record right whale calls and obtain cross‐bearings to the whales. Although previous work in the Bering Sea focused on detections of the right whale upsweep call, our findings suggest that the gunshot call is much more ubiquitous. Spatial and temporal trends of gunshot calls will be presented, and changes in gunshot call characteristics relative to observed surfacing sequences will be described. [Work supported by an interagency agreement from the Minerals Management Service.]

The hearing of polar bears is of great interest because little is known about hearing of large terrestrial carnivores, they are amphibious, their predatory habits differ from most bears, and there is an increasing need for data to manage anthropogenic noise in maternal denning habitat. Behavioral auditory thresholds were collected from two female polar bears at the San Diego Zoo (ZSSD) in 2006‐2007, and are now underway with two females and a male at SeaWorld San Diego (SWSD). Thresholds were measured at 19 frequencies between 125 Hz and 31.5 kHz using shaped 500 ms tones, a 'go/no‐go' response protocol, and staircase presentation order with catch trials. Holding areas in both facilities were sound‐isolated to the extent practicable. Threshold measurements were limited by background noise below 5 kHz, but sensitivity could be measured to below 0 dB at higher frequencies. To date, the bears have detected sounds down to the noise floor from 125 Hz to about 14 kHz. Their sensitivity declines rapidly above 20...