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Abundance and survival of Pacific humpback whales in a proposed critical habitat area.

https://arctichealth.org/en/permalink/ahliterature256981
Source
PLoS One. 2013;8(9):e75228
Publication Type
Article
Date
2013
Author
Erin Ashe
Janie Wray
Christopher R Picard
Rob Williams
Author Affiliation
Sea Mammal Research Unit, University of St. Andrews, St. Andrews, Fife, Scotland, United Kingdom ; Oceans Initiative, Pearse Island, BC Canada.
Source
PLoS One. 2013;8(9):e75228
Date
2013
Language
English
Publication Type
Article
Keywords
Animals
British Columbia
Ecological Parameter Monitoring
Ecosystem
Female
Humans
Humpback Whale - physiology
Male
Abstract
Humpback whales (Megaptera novaeangliae) were hunted commercially in Canada's Pacific region until 1966. Depleted to an estimated 1,400 individuals throughout the North Pacific, humpback whales are listed as Threatened under Canada's Species at Risk Act (SARA) and Endangered under the US Endangered Species Act. We conducted an 8-year photo-identification study to monitor humpback whale usage of a coastal fjord system in British Columbia (BC), Canada that was recently proposed as candidate critical habitat for the species under SARA. This participatory research program built collaborations among First Nations, environmental non-governmental organizations and academics. The study site, including the territorial waters of Gitga'at First Nation, is an important summertime feeding destination for migratory humpback whales, but is small relative to the population's range. We estimated abundance and survivorship using mark-recapture methods using photographs of naturally marked individuals. Abundance of humpback whales in the region was large, relative to the site's size, and generally increased throughout the study period. The resulting estimate of adult survivorship (0.979, 95% CI: 0.914, 0.995) is at the high end of previously reported estimates. A high rate of resights provides new evidence for inter-annual site fidelity to these local waters. Habitat characteristics of our study area are considered ecologically significant and unique, and this should be considered as regulatory agencies consider proposals for high-volume crude oil and liquefied natural gas tanker traffic through the area. Monitoring population recovery of a highly mobile, migratory species is daunting for low-cost, community-led science. Focusing on a small, important subset of the animals' range can make this challenge more tractable. Given low statistical power and high variability, our community is considering simpler ecological indicators of population health, such as the number of individuals harmed or killed each year by human activities, including ship strikes and entanglement in fishing gear.
Notes
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Cites: Biol Lett. 2011 Apr 23;7(2):299-30220943678
Cites: J Acoust Soc Am. 2012 Nov;132(5):EL423-823145705
Cites: Dis Aquat Organ. 2013 Apr 11;103(3):229-6423574708
Cites: Biometrika. 1965 Jun;52:225-4714341276
PubMed ID
24058666 View in PubMed
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Arctic science: The local perspective.

https://arctichealth.org/en/permalink/ahliterature130536
Source
Nature. 2011 Oct 13;478(7368):182-3
Publication Type
Article
Date
Oct-13-2011
Author
Henry P Huntington
Author Affiliation
Pew Environment Group, 23834 The Clearing Drive, Eagle River, Alaska 99577, USA. hhuntington@pewtrusts.org
Source
Nature. 2011 Oct 13;478(7368):182-3
Date
Oct-13-2011
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Beluga Whale - physiology
Bowhead Whale - physiology
Cooperative Behavior
Ecology - manpower - methods
Global Warming - statistics & numerical data
Humans
Knowledge
Population Groups
Research Personnel - education
PubMed ID
21993743 View in PubMed
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Assessment of management to mitigate anthropogenic effects on large whales.

https://arctichealth.org/en/permalink/ahliterature120256
Source
Conserv Biol. 2013 Feb;27(1):121-33
Publication Type
Article
Date
Feb-2013
Author
Julie M Van der Hoop
Michael J Moore
Susan G Barco
Timothy V N Cole
Pierre-Yves Daoust
Allison G Henry
Donald F McAlpine
William A McLellan
Tonya Wimmer
Andrew R Solow
Author Affiliation
Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA. jvanderhoop@whoi.edu
Source
Conserv Biol. 2013 Feb;27(1):121-33
Date
Feb-2013
Language
English
Publication Type
Article
Keywords
Animals
Canada
Conservation of Natural Resources - legislation & jurisprudence - methods
Human Activities
Humans
Population Dynamics
United States
Whales - physiology
Abstract
United States and Canadian governments have responded to legal requirements to reduce human-induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause-specific mortalities with time. We compared the number of human-caused mortalities with U.S. federally established levels of potential biological removal (i.e., species-specific sustainable human-caused mortality). From 1970 through 2009, 1762 mortalities (all known) and serious injuries (likely fatal) involved 8 species of large whales. We determined cause of death for 43% of all mortalities; of those, 67% (502) resulted from human interactions. Entanglement in fishing gear was the primary cause of death across all species (n = 323), followed by natural causes (n = 248) and vessel strikes (n = 171). Established sustainable levels of mortality were consistently exceeded in 2 species by up to 650%. Probabilities of entanglement and vessel-strike mortality increased significantly from 1990 through 2009. There was no significant change in the local intensity of all or vessel-strike mortalities before and after 2003, the year after which numerous mitigation efforts were enacted. So far, regulatory efforts have not reduced the lethal effects of human activities to large whales on a population-range basis, although we do not exclude the possibility of success of targeted measures for specific local habitats that were not within the resolution of our analyses. It is unclear how shortfalls in management design or compliance relate to our findings. Analyses such as the one we conducted are crucial in critically evaluating wildlife-management decisions. The results of these analyses can provide managers with direction for modifying regulated measures and can be applied globally to mortality-driven conservation issues.
Notes
Cites: Nature. 2001 Nov 29;414(6863):537-4111734852
Cites: Science. 2005 Jul 22;309(5734):561-216040692
Cites: Mar Pollut Bull. 2006 Oct;52(10):1287-9816712877
Cites: J Zoo Wildl Med. 2008 Mar;39(1):37-5518432095
Cites: Dis Aquat Organ. 2011 Oct 6;96(3):175-8522132496
PubMed ID
23025354 View in PubMed
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Assessment of neurotoxic effects of mercury in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) from the Canadian Arctic.

https://arctichealth.org/en/permalink/ahliterature263598
Source
Sci Total Environ. 2015 Mar 15;509-510:237-47
Publication Type
Article
Date
Mar-15-2015
Author
Anke Krey
Sonja K Ostertag
Hing Man Chan
Source
Sci Total Environ. 2015 Mar 15;509-510:237-47
Date
Mar-15-2015
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Beluga Whale - physiology
Canada
Environmental monitoring
Mercury - toxicity
Nervous System - drug effects
Pinnipedia - physiology
Seals, Earless - physiology
Ursidae - physiology
Water Pollutants, Chemical - toxicity
Abstract
Marine mammals are indicator species of the Arctic ecosystem and an integral component of the traditional Inuit diet. The potential neurotoxic effects of increased mercury (Hg) in beluga whales (Delphinapterus leucas), ringed seals (Pusa hispida), and polar bears (Ursus maritimus) are not clear. We assessed the risk of Hg-associated neurotoxicity to these species by comparing their brain Hg concentrations with threshold concentrations for toxic endpoints detected in laboratory animals and field observations: clinical symptoms (>6.75 mg/kg wet weight (ww)), neuropathological signs (>4 mg/kg ww), neurochemical changes (>0.4 mg/kg ww), and neurobehavioral changes (>0.1mg/kg ww). The total Hg (THg) concentrations in the cerebellum and frontal lobe of ringed seals and polar bears were 3mg/kg ww. Our results suggest that brain THg levels in polar bears are below levels that induce neurobehavioral effects as reported in the literature, while THg concentrations in ringed seals are within the range that elicit neurobehavioral effects and individual ringed seals exceed the threshold for neurochemical changes. The relatively high THg concentration in beluga whales exceeds all of the neurotoxicity thresholds assessed. High brain selenium (Se):Hg molar ratios were observed in all three species, suggesting that Se could protect the animals from Hg-associated neurotoxicity. This assessment was limited by several factors that influence neurotoxic effects in animals, including: animal species; form of Hg in the brain; and interactions with modifiers of Hg-associated toxicity, such as Se. Comparing brain Hg concentrations in wildlife with concentrations of appropriate laboratory studies can be used as a tool for risk characterization of the neurotoxic effects of Hg in Arctic marine mammals.
PubMed ID
24958011 View in PubMed
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Automated localization of whales in coastal fjords.

https://arctichealth.org/en/permalink/ahliterature307455
Source
J Acoust Soc Am. 2019 12; 146(6):4672
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
12-2019
Author
Benjamin Hendricks
Janie L Wray
Eric M Keen
Hussein M Alidina
T Aaron Gulliver
Chris R Picard
Author Affiliation
Department of Electrical and Computer Engineering, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
Source
J Acoust Soc Am. 2019 12; 146(6):4672
Date
12-2019
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Acoustics
Animals
Ecosystem
Estuaries
Fin Whale - physiology
Humpback Whale - physiology
Noise
Probability
Sound Localization - physiology
Vocalization, Animal - physiology
Whale, Killer - physiology
Abstract
Localization and tracking of vocalizing marine mammals are powerful tools for understanding and mitigating the impacts of anthropogenic stressors such as vessel noise on habitat use of cetaceans. A large-aperture hydrophone network has been installed in the Kitimat Fjord System, an ecologically, culturally, and economically valued marine environment in northern British Columbia, Canada. This network consists of four synchronized bottom-mounted hydrophones that permanently record and radio-transmit data to a land-based laboratory. An automated system has been developed which includes routines to localize transient bio-acoustic signals from three or more streaming hydrophones in near real-time. These routines comprise the correlation of hydrophone signals, the construction of a time lag model, and signal localization and error estimation from a spatial likelihood surface. The localization method was tested experimentally and subsequently applied to vocalizations from humpback whales, fin whales, and killer whales. Refractive and reflective sound propagation effects in the confined fjords are assessed using ray tracing propagation models. Automated localization results are compared to ground-truth data and shown to provide good accuracy.
PubMed ID
31893735 View in PubMed
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Baleen as a biomonitor of mercury content and dietary history of North Atlantic minke whales (Balaenopetra acutorostrata): combining elemental and stable isotope approaches.

https://arctichealth.org/en/permalink/ahliterature61529
Source
Sci Total Environ. 2004 Sep 20;331(1-3):69-82
Publication Type
Article
Date
Sep-20-2004
Author
K A Hobson
F F Riget
P M Outridge
R. Dietz
E. Born
Author Affiliation
Prairie and Northern Wildlife Research Center, Canadian Wildlife Service, 115 Perimeter Road, Saskatoon, SK, S7 N 0X4, Canada.
Source
Sci Total Environ. 2004 Sep 20;331(1-3):69-82
Date
Sep-20-2004
Language
English
Publication Type
Article
Keywords
Animals
Atlantic Ocean
Carbon Isotopes - analysis
Diet
Environmental Monitoring - methods
Female
Greenland
Male
Mercury - analysis - pharmacokinetics
Nitrogen Isotopes - analysis
Research Support, Non-U.S. Gov't
Tissue Distribution
Water Pollutants - analysis - pharmacokinetics
Whales - physiology
Abstract
Baleen is an incrementally-growing tissue of balaenopteran whales which preserves relatively well over time in museums and some archeological sites, and, therefore might be useful for studies examining long-term changes of metal levels in whales. This study examined Hg and stable C and N isotopic composition of baleen plates of the North Atlantic minke whale (Balaenoptera acutorostrata), which continues to be a food source for people in Greenland and elsewhere. We compared the Hg levels and stable isotopes of major tissues (kidney, liver and muscle) with those of baleen plates to see whether baleen could be used as a biomonitor of variations of Hg intake and diet both between individuals and within individuals over time. Mercury was significantly correlated with concentrations in all tissues (kidney, liver and muscle). Stable C and N isotopes in baleen were generally similar to those of muscle, which reflects the recent (approximately one month) feeding of the whale, but in some individuals there were significant differences between baleen and muscle. Sectioning of baleen into 1 cm longitudinal increments showed that these differences were due to marked dietary shifts by some individuals over time that had been recorded in the baleen but were lost from the muscle record. Whole baleen C and N isotopes were better correlated with tissue Hg levels, suggesting that baleen may provide a more reliable indicator of long-term average diet, which in turn may be better related to Hg accumulation in tissues than the shorter-term diet record contained in muscle.
PubMed ID
15325142 View in PubMed
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Baseline hearing abilities and variability in wild beluga whales (Delphinapterus leucas).

https://arctichealth.org/en/permalink/ahliterature260077
Source
J Exp Biol. 2014 May 15;217(Pt 10):1682-91
Publication Type
Article
Date
May-15-2014
Author
Manuel Castellote
T Aran Mooney
Lori Quakenbush
Roderick Hobbs
Caroline Goertz
Eric Gaglione
Source
J Exp Biol. 2014 May 15;217(Pt 10):1682-91
Date
May-15-2014
Language
English
Publication Type
Article
Keywords
Alaska
Animals
Auditory Threshold
Beluga Whale - physiology
Evoked Potentials, Auditory
Female
Hearing
Male
Noise
Abstract
While hearing is the primary sensory modality for odontocetes, there are few data addressing variation within a natural population. This work describes the hearing ranges (4-150 kHz) and sensitivities of seven apparently healthy, wild beluga whales (Delphinapterus leucas) during a population health assessment project that captured and released belugas in Bristol Bay, Alaska. The baseline hearing abilities and subsequent variations were addressed. Hearing was measured using auditory evoked potentials (AEPs). All audiograms showed a typical cetacean U-shape; substantial variation (>30 dB) was found between most and least sensitive thresholds. All animals heard well, up to at least 128 kHz. Two heard up to 150 kHz. Lowest auditory thresholds (35-45 dB) were identified in the range 45-80 kHz. Greatest differences in hearing abilities occurred at both the high end of the auditory range and at frequencies of maximum sensitivity. In general, wild beluga hearing was quite sensitive. Hearing abilities were similar to those of belugas measured in zoological settings, reinforcing the comparative importance of both settings. The relative degree of variability across the wild belugas suggests that audiograms from multiple individuals are needed to properly describe the maximum sensitivity and population variance for odontocetes. Hearing measures were easily incorporated into field-based settings. This detailed examination of hearing abilities in wild Bristol Bay belugas provides a basis for a better understanding of the potential impact of anthropogenic noise on a noise-sensitive species. Such information may help design noise-limiting mitigation measures that could be applied to areas heavily influenced and inhabited by endangered belugas.
PubMed ID
24829324 View in PubMed
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Bowhead whale acoustic activity in the southeast Beaufort Sea during late summer 2008-2010.

https://arctichealth.org/en/permalink/ahliterature268610
Source
J Acoust Soc Am. 2013 Dec;134(6):4323
Publication Type
Article
Date
Dec-2013
Author
Russell A Charif
Ashakur Rahaman
Charles A Muirhead
Michael S Pitzrick
Ann M Warde
James Hall
Cynthia Pyc
Christopher W Clark
Source
J Acoust Soc Am. 2013 Dec;134(6):4323
Date
Dec-2013
Language
English
Publication Type
Article
Keywords
Acoustics - instrumentation
Animals
Bowhead Whale - physiology
Ecosystem
Environmental Monitoring - methods
Seasons
Signal Processing, Computer-Assisted
Sound Spectrography
Time Factors
Transducers
Vocalization, Animal
Abstract
Autonomous passive acoustic recorders were deployed to record sounds of bowhead whales (Balaena mysticetus) in the southeast Beaufort Sea for periods of 30-55 days during the late summer, open-water seasons of 2008-2010. Recordings were made in three areas licensed for hydrocarbon exploration, spanning the continental slope and adjacent outer shelf, and in a shallow inner-shelf area where bowheads have been observed congregating to feed in recent decades. Bowhead sounds were counted in samples comprising 10% of each recorded hour. In mid-August and September in all 3 years, the rate of bowhead calling at outer shelf sites exceeded that at adjacent continental slope sites by one to two orders of magnitude. Higher rates of calling occurred on the slope in late July and early August than at later dates. Calling rates varied by an order of magnitude between years in the one area that was monitored in different years. The highest rates of calling occurred on the inner shelf, offshore of the northern Tuktoyaktuk Peninsula. These trends are consistent with patterns of habitat use previously reported from aerial surveys in this and nearby areas of the Beaufort Sea and with the results of satellite tagging studies.
PubMed ID
25669244 View in PubMed
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Bowhead whales use two foraging strategies in response to fine-scale differences in zooplankton vertical distribution.

https://arctichealth.org/en/permalink/ahliterature311518
Source
Sci Rep. 2020 11 20; 10(1):20249
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
11-20-2020
Author
Sarah M E Fortune
Steven H Ferguson
Andrew W Trites
Justine M Hudson
Mark F Baumgartner
Author Affiliation
Marine Mammal Research Unit, Institute for the Oceans and Fisheries, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada. sarahmefortune@gmail.com.
Source
Sci Rep. 2020 11 20; 10(1):20249
Date
11-20-2020
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Bowhead Whale - physiology
Feeding Behavior - physiology
Zooplankton
Abstract
As zooplanktivorous predators, bowhead whales (Balaena mysticetus) must routinely locate patches of prey that are energy-rich enough to meet their metabolic needs. However, little is known about how the quality and quantity of prey might influence their feeding behaviours. We addressed this question using a new approach that included: (1) multi-scale biologging and unmanned aerial system observations of bowhead whales in Cumberland Sound, Nunavut (Canada), and (2) an optical plankton counter (OPC) and net collections to identify and enumerate copepod prey species through the water column. The OPC data revealed two prey layers comprised almost exclusively of lipid-rich calanoid copepods. The deep layer contained fewer, but larger, particles (10% greater overall biomass) than the shallow prey layer. Dive data indicated that the whales conducted long deep Square-shaped dives (80% of dives; averaging depth of 260.4 m) and short shallow Square-shaped dives (16%; averaging depth of 22.5 m) to feed. The whales tended to dive proportionally more to the greater biomass of zooplankton that occurred at depth. Combining behavioural recordings with prey sampling showed a more complex feeding ecology than previously understood, and provides a means to evaluate the energetic balance of individuals under current environmental conditions.
PubMed ID
33219277 View in PubMed
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Calibration and comparison of the acoustic location methods used during the spring migration of the bowhead whale, Balaena mysticetus, off Pt. Barrow, Alaska, 1984-1993.

https://arctichealth.org/en/permalink/ahliterature198053
Source
J Acoust Soc Am. 2000 Jun;107(6):3509-17
Publication Type
Article
Date
Jun-2000
Author
C W Clark
W T Ellison
Author Affiliation
Cornell Lab of Ornithology, Bioacoustics Research Program, Ithaca, New York 14850, USA. cwc2@cornell.edu
Source
J Acoust Soc Am. 2000 Jun;107(6):3509-17
Date
Jun-2000
Language
English
Publication Type
Article
Keywords
Acoustics
Alaska
Animals
Humans
Models, Biological
Seasons
Whales - physiology
Abstract
Between 1984 and 1993, visual and acoustic methods were combined to census the Bering-Chukchi-Beaufort bowhead whale, Balaena mysticetus, population. Passive acoustic location was based on arrival-time differences of transient bowhead sounds detected on sparse arrays of three to five hydrophones distributed over distances of 1.5-4.5 km along the ice edge. Arrival-time differences were calculated from either digital cross correlation of spectrograms (old method), or digital cross correlation of time waveforms (new method). Acoustic calibration was conducted in situ in 1985 at five sites with visual site position determined by triangulation using two theodolites. The discrepancy between visual and acoustic locations was
PubMed ID
10875395 View in PubMed
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40 records – page 1 of 4.