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1.
R Soc Open Sci ; 11(4): 240058, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38633351

ABSTRACT

This review comprehensively evaluates the impacts of anthropogenic threats on beaked whales (Ziphiidae)-a taxonomic group characterized by cryptic biology, deep dives and remote offshore habitat, which have challenged direct scientific observation. By synthesizing information published in peer-reviewed studies and grey literature, we identified available evidence of impacts across 14 threats for each Ziphiidae species. Threats were assessed based on their pathways of effects on individuals, revealing many gaps in scientific understanding of the risks faced by beaked whales. By applying a comprehensive taxon-level analysis, we found evidence that all beaked whale species are affected by multiple stressors, with climate change, entanglement and plastic pollution being the most common threats documented across beaked whale species. Threats assessed as having a serious impact on individuals included whaling, military sonar, entanglement, depredation, vessel strikes, plastics and oil spills. This review emphasizes the urgent need for targeted research to address a range of uncertainties, including cumulative and population-level impacts. Understanding the evidence and pathways of the effects of stressors on individuals can support future assessments, guide practical mitigation strategies and advance current understanding of anthropogenic impacts on rare and elusive marine species.

2.
J Acoust Soc Am ; 155(1): 145-155, 2024 01 01.
Article in English | MEDLINE | ID: mdl-38180155

ABSTRACT

The call characteristics and vocal behaviour of sei whales (Balaenoptera borealis) off eastern Canada, including potential spatiotemporal variation, is poorly understood. Such information can improve the performance of automated detector-classifiers, enhancing the accuracy and efficiency of identifying sei whales in large acoustic datasets. Ultimately, these data can be used to understand the occurrence, distribution, and population structure of sei whales in Atlantic Canada. We measured sei whale downsweep characteristics recorded from six locations off Nova Scotia (NS) and Newfoundland and Labrador (NFLD), Canada over a two-year period (2015-2017), and examined variation between call subtypes (singlets, doublets, triplets+), and seasons (Spring, Summer, Fall, Winter). We found that downsweeps had a mean duration of 1.58 s, sweeping from 75.66 to 34.22 Hz, with a peak frequency of 43.89 Hz and an intra-call interval of 2.22 s. Most call characteristics did not vary between location, subtype, or season; however, significantly longer downsweeps occurred off NS, within doublet calls, and in fall months. We also found that NFLD had a higher proportion of doublets (70%) than NS (52%). This variation may be evidence of acoustically diverging sei whale populations, as well as useful for improving detector-classifiers of sei whales in the region.


Subject(s)
Acoustics , Balaenoptera , Animals , Canada , Cytoskeleton , Seasons
3.
Sci Rep ; 12(1): 1973, 2022 02 07.
Article in English | MEDLINE | ID: mdl-35132140

ABSTRACT

Experimental research has shown that beaked whales exhibit strong avoidance reactions to naval active sonars used during antisubmarine warfare training exercises, including cessation of echolocation and foraging activity. Behavioural responses to sonar have also been linked to strandings and mortality. Much of the research on the responses of beaked whales and other cetaceans to naval active sonar has occurred on or near U.S. naval training ranges, and the impacts of sonar in other regions remain poorly understood, particularly as these impacts, including mortality, are likely to go unobserved in offshore areas. In September 2016 the multinational naval exercise 'CUTLASS FURY 2016' (CF16) was conducted off eastern Canada. We used passive acoustic recordings collected in the region to quantify the occurrence and characteristics of sonar signals, measure ambient noise levels, and assess changes in the acoustic activity of beaked and sperm whales. The number of hours per day with echolocation clicks from Cuvier's beaked whales and sperm whales were significantly reduced during CF16, compared to the pre-exercise period in 2016 (sperm whales) and to control data from 2015 (both species). Clicks from an unidentified Mesoplodont beaked whale species, sporadically detected prior to CF16, were absent during the exercise and for 7 days afterward. These results suggest that beaked and sperm whales ceased foraging in the vicinity of CF16 and likely avoided the affected area. Such disturbance may have energetic, health, and fitness consequences.


Subject(s)
Echolocation , Sound/adverse effects , Sperm Whale/physiology , Sperm Whale/psychology , Warfare , Whales/physiology , Whales/psychology , Animals , Avoidance Learning , Canada , Diving , Feeding Behavior
4.
Mar Pollut Bull ; 175: 113361, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35077924

ABSTRACT

Anthropogenic underwater noise has been identified as a potentially serious stressor for the critically endangered North Atlantic right whale (NARW). The Government of Canada is undertaking steps to better characterize the noise sources of most concern and their associated impacts, but there is currently an insufficient understanding of which noise sources are most impacting NARW in their Canadian habitat. This knowledge gap together with the myriad possible methods and metrics for quantifying underwater noise presents a confounding and challenging problem that risks delaying timely mitigation. This study presents the results from a 2020 workshop aimed at developing a series of metrics recommended specifically for better characterizing the types of noise deemed of greatest concern for NARW in Canadian waters. The recommendations provide a basis for more targeted research on noise impacts and set the stage for more effective management and protection of NARW, with potential conservation applications to similar species.


Subject(s)
Benchmarking , Whales , Animals , Atlantic Ocean , Canada , Ecosystem , Noise
5.
JASA Express Lett ; 1(1): 011203, 2021 Jan.
Article in English | MEDLINE | ID: mdl-36154092

ABSTRACT

This Letter proposes a frequency scaling for processing, storing, and sharing high-bandwidth, passive acoustic spectral data that optimizes data volume while maintaining reasonable data resolution. The format is a hybrid that uses 1 Hz resolution up to 455 Hz and millidecade frequency bands above 455 Hz. This hybrid is appropriate for many types of soundscape analysis, including detecting different types of soundscapes and regulatory applications like computing weighted sound exposure levels. Hybrid millidecade files are compressed compared to the 1 Hz equivalent such that one research center could feasibly store data from hundreds of projects for sharing among researchers globally.

6.
JASA Express Lett ; 1(8): 081201, 2021 08.
Article in English | MEDLINE | ID: mdl-36154245

ABSTRACT

In the original paper [JASA Express Lett. 1(1), 011203 (2021)], a method for processing, storing, and sharing high-bandwidth, passive acoustic spectral data that optimizes data volume while maintaining reasonable data resolution was proposed. The format was a hybrid that uses 1-Hz resolution up to 455 Hz and millidecade frequency bands above 455 Hz. The choice of 455 Hz was based on a method of computing the edge frequencies of millidecade bands that is not compatible with summing millidecades to decidecades. This has been corrected. The new transition frequency is the first frequency with a millidecade with greater than 1 Hz, 435 Hz.

7.
Glob Chang Biol ; 26(9): 4812-4840, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32450009

ABSTRACT

Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate-driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottom-mounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004-2010 and 2011-2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid-Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution.


Subject(s)
Acoustics , Animals , Atlantic Ocean , Caribbean Region , Greenland , Southeastern United States
8.
J Acoust Soc Am ; 146(1): 307, 2019 07.
Article in English | MEDLINE | ID: mdl-31370599

ABSTRACT

Passive acoustic monitoring (PAM) is crucial to expanding the knowledge of beaked whales, including the northern bottlenose whale (Hyperoodon ampullatus) and Sowerby's beaked whale (Mesoplodon bidens). Existing descriptions of clicks produced by these species are limited by sample size, number of individuals recorded, and geographic scope. Data from multiple encounters in the western North Atlantic are used to provide a quantitative description of clicks produced by these species. Recordings from nine encounters with northern bottlenose whales in Nova Scotia and Newfoundland were analyzed (N = 2239 clicks). The click type described had a median peak frequency of 25.9 kHz (10th-90th percentile range: 22.9-29.3 kHz), and a median inter-click interval (ICI) of 402 ms (N = 1917, 10th-90th percentile range: 290-524 ms). Recordings from 18 Sowerby's beaked whale encounters from Nova Scotia were analyzed (N = 762 clicks). The click type described had a median peak frequency of 65.8 kHz (10th-90th percentile range: 61.5-76.5 kHz), and a median ICI of 237 ms (N = 677, 10th-90th percentile range: 130-315 ms). These results will contribute to the development of methods to detect and classify beaked whale clicks to the species level, improving the effectiveness of PAM and enhancing scientific understanding and conservation efforts for cryptic and at-risk cetaceans.

9.
J Acoust Soc Am ; 145(4): 2305, 2019 04.
Article in English | MEDLINE | ID: mdl-31046358

ABSTRACT

Humpback whale songs have been described worldwide and studies exploring non-song vocal behavior continue to expand; however, studies on the transition periods when whales shift to and from the seasonal behavioral state of singing are lacking and may be potentially informative regarding the proximal factors controlling the onset and offset of humpback whale male singing. Acoustic recorders collected data off eastern Canada continuously from the Bay of Fundy in the fall of 2015 and near-continuously off northeast Nova Scotia in the spring of 2016. Humpback whale acoustic occurrence and behavior were identified by systematically reviewing a subset of acoustic recordings for presence before analyzing the highest quality recordings for behavior. The onset of singing in the fall was gradual over a period of about three weeks with an intermediate form, termed "song fragment," occurring prior to full songs. In comparison, singing in the spring seemed to end abruptly with few song fragments. Song fragments could be produced by juveniles learning to sing for the first time or mature males preparing for breeding activities prior to migrating to southern breeding grounds. The authors propose an alternative hypothesis that the timing and manner of transitions could be driven by physiological processes similar to those documented in songbirds.

10.
Sci Rep ; 7(1): 13460, 2017 10 18.
Article in English | MEDLINE | ID: mdl-29044130

ABSTRACT

Given new distribution patterns of the endangered North Atlantic right whale (NARW; Eubalaena glacialis) population in recent years, an improved understanding of spatio-temporal movements are imperative for the conservation of this species. While so far visual data have provided most information on NARW movements, passive acoustic monitoring (PAM) was used in this study in order to better capture year-round NARW presence. This project used PAM data from 2004 to 2014 collected by 19 organizations throughout the western North Atlantic Ocean. Overall, data from 324 recorders (35,600 days) were processed and analyzed using a classification and detection system. Results highlight almost year-round habitat use of the western North Atlantic Ocean, with a decrease in detections in waters off Cape Hatteras, North Carolina in summer and fall. Data collected post 2010 showed an increased NARW presence in the mid-Atlantic region and a simultaneous decrease in the northern Gulf of Maine. In addition, NARWs were widely distributed across most regions throughout winter months. This study demonstrates that a large-scale analysis of PAM data provides significant value to understanding and tracking shifts in large whale movements over long time scales.


Subject(s)
Acoustics , Whales , Animals , Atlantic Ocean , Geography , Population Dynamics , Spatial Analysis
11.
Appl Neuropsychol Adult ; 24(1): 65-72, 2017.
Article in English | MEDLINE | ID: mdl-26979300

ABSTRACT

The Boston Naming Test (BNT) was designed to present items in order of difficulty based on word frequency. Changes in word frequencies over time, however, would frustrate extrapolation in clinical and research settings based on the theoretical construct because performance on the BNT might reflect changes in ecological frequency of the test items, rather than performance across items of increasing difficulty. This study identifies the ecological frequency of BNT items at the time of publication using the American Heritage Word Frequency Book and determines changes in frequency over time based on the frequency distribution of BNT items across a current corpus, the Corpus of Contemporary American English. Findings reveal an uneven distribution of BNT items across 2 corpora and instances of negligible differentiation in relative word frequency across test items. As BNT items are not presented in order from least to most frequent, clinicians and researchers should exercise caution in relying on the BNT as presenting items in increasing order of difficulty. A method is proposed for distributing confrontation-naming items to be explicitly measured against test items that are normally distributed across the corpus of a given language.


Subject(s)
Mental Recall/physiology , Names , Neuropsychological Tests/standards , Vocabulary , Humans
12.
J Acoust Soc Am ; 140(1): EL31, 2016 07.
Article in English | MEDLINE | ID: mdl-27475208

ABSTRACT

This study investigated the effects of using duty-cycled passive acoustic recordings to monitor the daily presence of beaked whale species at three locations in the northwest Atlantic. Continuous acoustic records were subsampled to simulate duty cycles of 50%, 25%, and 10% and cycle period durations from 10 to 60 min. Short, frequent listening periods were most effective for assessing the daily presence of beaked whales. Furthermore, subsampling at low duty cycles led to consistently greater underestimation of Mesoplodon species than either Cuvier's beaked whales or northern bottlenose whales, leading to a potential bias in estimation of relative species occurrence.


Subject(s)
Vocalization, Animal , Whales/physiology , Acoustics , Animals , Atlantic Ocean , Population Surveillance/methods , Time Factors
13.
Eur J Oncol Nurs ; 17(4): 490-7, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23182602

ABSTRACT

AIM: To investigate complementary and alternative medicine (CAM) use among women with breast cancer in Ireland using a mixed methods modified sequential explanatory design. METHODS: Semi-structured interviews were conducted with oncology professionals (n = 20) and CAM practitioners (n = 20) and this was followed by a survey of 406 women with breast cancer using the 'Use of Complementary and Alternative Therapies Survey' questionnaire (UCATS) (Lengacher et al., 2003). Follow up interviews were subsequently undertaken with a subset of this survey sample (n = 31). RESULTS: Over half of those surveyed (55.7%, n = 226) used some form of CAM since diagnosis. The most frequently used therapies were massage, herbal supplements (including herbs with oestrogenic properties), antioxidants, relaxation, counselling, health supplements, reflexology, reiki and support groups. Dietary interventions were used primarily to reduce symptoms and/or side effects while reduction of psychological stress was the primary reason for use of stress-reducing therapies. Most respondents reported that the CAM therapies they had used were helpful. The qualitative data elaborated on and provided clarification of the survey results. CONCLUSIONS: Similar to international studies, CAM is popular among women with breast cancer in Ireland. As such, the challenge for Irish oncology professionals is to identify low risk CAM therapies that are likely to benefit patients while educating patients and themselves on therapies which may be of concern. This study clearly illustrates the benefits of using a mixed methods approach to enhance our understanding of a complex clinical issue and thus we recommend that this method should be the method of choice when planning health services research.


Subject(s)
Breast Neoplasms/therapy , Complementary Therapies/statistics & numerical data , Adult , Aged , Complementary Therapies/methods , Female , Humans , Interviews as Topic , Ireland , Logistic Models , Middle Aged , Qualitative Research , Self-Help Groups/statistics & numerical data , Surveys and Questionnaires
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