keyword
MENU ▼
Read by QxMD icon Read
search

Killer whales

keyword
https://www.readbyqxmd.com/read/28876915/effects-of-polar-bear-and-killer-whale-derived-contaminant-cocktails-on-marine-mammal-immunity
#1
Jean-Pierre Desforges, Milton Levin, Lindsay Jasperse, Sylvain De Guise, Igor Eulaers, Robert J Letcher, Mario Acquarone, Erling Nordoy, Lars Folkow, Trine Hammer Jensen, Carsten Grondahl, Mads F Bertelsen, Judy St Leger, Javier Almunia, Christian Sonne, Rune Dietz
Most controlled toxicity studies use single chemical exposures that do not represent the real world situation of complex mixtures of known and unknown natural and anthropogenic substances. In the present study, complex contaminant cocktails derived from the blubber of polar bears (PB; Ursus maritimus) and killer whales (KW; Orcinus orca) were used for in vitro concentration-response experiments with PB, cetacean and seal spp. immune cells to evaluate the effect of realistic contaminant mixtures on various immune functions...
September 6, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28767655/beluga-whale-summer-habitat-associations-in-the-nelson-river-estuary-western-hudson-bay-canada
#2
Alexander J Smith, Jeff W Higdon, Pierre Richard, Jack Orr, Warren Bernhardt, Steven H Ferguson
To understand beluga whale (Delphinapterus leucas) estuarine use in the Nelson River estuary, southwest Hudson Bay, we recorded and examined beluga movements and habitat associations for the July through August period in 2002-2005. We compared locations of belugas fitted with satellite transmitters ("tags") (2002-2005) and aerial-surveyed (2003 and 2005) belugas for years of differing freshwater flow from the Nelson River which is influenced by hydroelectric activity. Using the beluga telemetry location data, we estimated an early August behavioral shift in beluga distribution patterns from local estuarine use to a progressively more migratory behavior away from the estuary...
2017: PloS One
https://www.readbyqxmd.com/read/28739936/gene-culture-coevolution-in-whales-and-dolphins
#3
Hal Whitehead
Whales and dolphins (Cetacea) have excellent social learning skills as well as a long and strong mother-calf bond. These features produce stable cultures, and, in some species, sympatric groups with different cultures. There is evidence and speculation that this cultural transmission of behavior has affected gene distributions. Culture seems to have driven killer whales into distinct ecotypes, which may be incipient species or subspecies. There are ecotype-specific signals of selection in functional genes that correspond to cultural foraging behavior and habitat use by the different ecotypes...
July 24, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28695252/oil-spills-and-marine-mammals-in-british-columbia-canada-development-and-application-of-a-risk-based-conceptual-framework
#4
Adrianne L Jarvela Rosenberger, Misty MacDuffee, Andrew G J Rosenberger, Peter S Ross
Marine mammals are inherently vulnerable to oil spills. We developed a conceptual framework to evaluate the impacts of potential oil exposure on marine mammals and applied it to 21 species inhabiting coastal British Columbia (BC), Canada. Oil spill vulnerability was determined by examining both the likelihood of species-specific (individual) oil exposure and the consequent likelihood of population-level effects. Oil exposure pathways, ecology, and physiological characteristics were first used to assign species-specific vulnerability rankings...
July 2017: Archives of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/28666015/first-longitudinal-study-of-seal-feeding-killer-whales-orcinus-orca-in-norwegian-coastal-waters
#5
Eve Jourdain, Dag Vongraven, Anna Bisther, Richard Karoliussen
Killer whales (Orcinus orca) have been documented preying on either fish or marine mammals in several regions, suggesting that this odontocete species has the ability to specialize on different types of prey. Off Norway, killer whales have been shown to rely on the Atlantic herring (Clupea harengus) as a main prey resource. Infrequent observations have revealed seals as an additional component of their diet, yet the extent of predation on marine mammals has remained largely unknown. Here, we present the findings of 29 years of photographic and observational data on seal-feeding killer whale groups identified in Norwegian coastal waters...
2017: PloS One
https://www.readbyqxmd.com/read/28662095/population-growth-is-limited-by-nutritional-impacts-on-pregnancy-success-in-endangered-southern-resident-killer-whales-orcinus-orca
#6
Samuel K Wasser, Jessica I Lundin, Katherine Ayres, Elizabeth Seely, Deborah Giles, Kenneth Balcomb, Jennifer Hempelmann, Kim Parsons, Rebecca Booth
The Southern Resident killer whale population (Orcinus orca) was listed as endangered in 2005 and shows little sign of recovery. These fish eating whales feed primarily on endangered Chinook salmon. Population growth is constrained by low offspring production for the number of reproductive females in the population. Lack of prey, increased toxins and vessel disturbance have been listed as potential causes of the whale's decline, but partitioning these pressures has been difficult. We validated and applied temporal measures of progesterone and testosterone metabolites to assess occurrence, stage and health of pregnancy from genotyped killer whale feces collected using detection dogs...
2017: PloS One
https://www.readbyqxmd.com/read/28649267/evidence-for-a-postreproductive-phase-in-female-false-killer-whales-pseudorca-crassidens
#7
Theoni Photopoulou, Ines M Ferreira, Peter B Best, Toshio Kasuya, Helene Marsh
BACKGROUND: A substantial period of life after reproduction ends, known as postreproductive lifespan (PRLS), is at odds with classical life history theory and its causes and mechanisms have puzzled evolutionary biologists for decades. Prolonged PRLS has been confirmed in only two non-human mammals, both odontocete cetaceans in the family Delphinidae. We investigate the evidence for PRLS in a third species, the false killer whale, Pseudorca crassidens, using a quantitative measure of PRLS and morphological evidence from reproductive tissues...
2017: Frontiers in Zoology
https://www.readbyqxmd.com/read/28636677/contextual-imitation-of-intransitive-body-actions-in-a-beluga-whale-delphinapterus-leucas-a-do-as-other-does-study
#8
José Z Abramson, Mª Victoria Hernández-Lloreda, José-Antonio Esteban, Fernando Colmenares, Francisco Aboitiz, Josep Call
Cetaceans are remarkable for exhibiting group-specific behavioral traditions or cultures in several behavioral domains (e.g., calls, behavioral tactics), and the question of whether they can be acquired socially, for example through imitative processes, remains open. Here we used a "Do as other does" paradigm to experimentally study the ability of a beluga to imitate familiar intransitive (body-oriented) actions demonstrated by a conspecific. The participant was first trained to copy three familiar behaviors on command (training phase) and then was tested for her ability to generalize the learned "Do as the other does" command to a different set of three familiar behaviors (testing phase)...
2017: PloS One
https://www.readbyqxmd.com/read/28554115/blubber-depth-distribution-and-bioaccumulation-of-pcbs-and-organochlorine-pesticides-in-arctic-invading-killer-whales
#9
Sara Pedro, Conor Boba, Rune Dietz, Christian Sonne, Aqqalu Rosing-Asvid, Martin Hansen, Anthony Provatas, Melissa A McKinney
Sightings of killer whales (Orcinus orca) in Greenland have increased in recent years, coincident with sea ice loss. These killer whales are likely from fish-feeding North Atlantic populations, but may have access to marine mammal prey in Greenlandic waters, which could lead to increased exposures to biomagnifying contaminants. Most studies on polychlorinated biphenyl (PCB) and organochlorine (OC) contaminants in killer whales have used biopsies which may not be representative of contaminant concentrations through the entire blubber depth...
December 1, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28528419/a-risk-based-characterization-of-sediment-contamination-by-legacy-and-emergent-contaminants-of-concern-in-coastal-british-columbia-canada
#10
Carmen Morales-Caselles, Jean-Pierre W Desforges, Neil Dangerfield, Peter S Ross
Sediments have long been used to help describe pollution sources, contaminated sites, trends over time, and habitat quality for marine life. We collected surficial sediments from 12 sites at an average seawater depth of 25 m in three near-urban areas of the Salish Sea (British Columbia, Canada) to investigate habitat quality for marine life, including heavily contaminated killer whales. Samples were analyzed using high-resolution instrumentation for a wide variety of congeners of polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), hexabromocyclododecane (HBCDD), polybrominated biphenyls, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans, organochlorine pesticides, and polychlorinated naphthalenes (PCNs)...
August 2017: Archives of Environmental Contamination and Toxicology
https://www.readbyqxmd.com/read/28464669/killer-whale-orcinus-orca-behavioral-audiograms
#11
Brian K Branstetter, Judy St Leger, Doug Acton, John Stewart, Dorian Houser, James J Finneran, Keith Jenkins
Killer whales (Orcinus orca) are one of the most cosmopolitan marine mammal species with potential widespread exposure to anthropogenic noise impacts. Previous audiometric data on this species were from two adult females [Szymanski, Bain, Kiehl, Pennington, Wong, and Henry (1999). J. Acoust. Soc. Am. 108, 1322-1326] and one sub-adult male [Hall and Johnson (1972). J. Acoust. Soc. Am. 51, 515-517] with apparent high-frequency hearing loss. All three killer whales had best sensitivity between 15 and 20 kHz, with thresholds lower than any odontocete tested to date, suggesting this species might be particularly sensitive to acoustic disturbance...
April 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28341854/gliding-locomotion-of-manta-rays-killer-whales-and-swordfish-near-the-water-surface
#12
Jie-Min Zhan, Ye-Jun Gong, Tian-Zeng Li
The hydrodynamic performance of the locomotive near the water surface is impacted by its geometrical shape. For marine animals, their geometrical shape is naturally selective; thus, investigating gliding locomotion of marine animal under the water surface may be able to elucidate the influence of the geometrical shape. We investigate three marine animals with specific geometries: the killer whale is fusiform shaped; the manta ray is flat and broad-winged; and the swordfish is best streamlined. The numerical results are validated by the measured drag coefficients of the manta ray model in a towing tank...
March 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28341851/respiratory-microbiome-of-endangered-southern-resident-killer-whales-and-microbiota-of-surrounding-sea-surface-microlayer-in-the-eastern-north-pacific
#13
Stephen A Raverty, Linda D Rhodes, Erin Zabek, Azad Eshghi, Caroline E Cameron, M Bradley Hanson, J Pete Schroeder
In the Salish Sea, the endangered Southern Resident Killer Whale (SRKW) is a high trophic indicator of ecosystem health. Three major threats have been identified for this population: reduced prey availability, anthropogenic contaminants, and marine vessel disturbances. These perturbations can culminate in significant morbidity and mortality, usually associated with secondary infections that have a predilection to the respiratory system. To characterize the composition of the respiratory microbiota and identify recognized pathogens of SRKW, exhaled breath samples were collected between 2006-2009 and analyzed for bacteria, fungi and viruses using (1) culture-dependent, targeted PCR-based methodologies and (2) taxonomically broad, non-culture dependent PCR-based methodologies...
March 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28275880/cultural-hitchhiking-in-the-matrilineal-whales
#14
Hal Whitehead, Felicia Vachon, Timothy R Frasier
Five species of whale with matrilineal social systems (daughters remain with mothers) have remarkably low levels of mitochondrial DNA diversity. Non-heritable matriline-level demography could reduce genetic diversity but the required conditions are not consistent with the natural histories of the matrilineal whales. The diversity of nuclear microsatellites is little reduced in the matrilineal whales arguing against bottlenecks. Selective sweeps of the mitochondrial genome are feasible causes but it is not clear why these only occurred in the matrilineal species...
March 9, 2017: Behavior Genetics
https://www.readbyqxmd.com/read/28273531/a-rapid-analytical-method-to-quantify-complex-organohalogen-contaminant-mixtures-in-large-samples-of-high-lipid-mammalian-tissues
#15
Jean-Pierre Desforges, Igor Eulaers, Luke Periard, Christian Sonne, Rune Dietz, Robert J Letcher
In vitro investigations of the health impact of individual chemical compounds have traditionally been used in risk assessments. However, humans and wildlife are exposed to a plethora of potentially harmful chemicals, including organohalogen contaminants (OHCs). An alternative exposure approach to individual or simple mixtures of synthetic OHCs is to isolate the complex mixture present in free-ranging wildlife, often non-destructively sampled from lipid rich adipose. High concentration stock volumes required for in vitro investigations do, however, pose a great analytical challenge to extract sufficient amounts of complex OHC cocktails...
June 2017: Chemosphere
https://www.readbyqxmd.com/read/28250185/epistatic-interactions-influence-terrestrial-marine-functional-shifts-in-cetacean-rhodopsin
#16
Sarah Z Dungan, Belinda S W Chang
Like many aquatic vertebrates, whales have blue-shifting spectral tuning substitutions in the dim-light visual pigment, rhodopsin, that are thought to increase photosensitivity in underwater environments. We have discovered that known spectral tuning substitutions also have surprising epistatic effects on another function of rhodopsin, the kinetic rates associated with light-activated intermediates. By using absorbance spectroscopy and fluorescence-based retinal release assays on heterologously expressed rhodopsin, we assessed both spectral and kinetic differences between cetaceans (killer whale) and terrestrial outgroups (hippo, bovine)...
March 15, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28239473/fine-scale-foraging-movements-by-fish-eating-killer-whales-orcinus-orca-relate-to-the-vertical-distributions-and-escape-responses-of-salmonid-prey-oncorhynchus-spp
#17
Brianna M Wright, John K B Ford, Graeme M Ellis, Volker B Deecke, Ari Daniel Shapiro, Brian C Battaile, Andrew W Trites
BACKGROUND: We sought to quantitatively describe the fine-scale foraging behavior of northern resident killer whales (Orcinus orca), a population of fish-eating killer whales that feeds almost exclusively on Pacific salmon (Oncorhynchus spp.). To reconstruct the underwater movements of these specialist predators, we deployed 34 biologging Dtags on 32 individuals and collected high-resolution, three-dimensional accelerometry and acoustic data. We used the resulting dive paths to compare killer whale foraging behavior to the distributions of different salmonid prey species...
2017: Movement Ecology
https://www.readbyqxmd.com/read/28223481/sustained-disruption-of-narwhal-habitat-use-and-behavior-in-the-presence-of-arctic-killer-whales
#18
Greg A Breed, Cory J D Matthews, Marianne Marcoux, Jeff W Higdon, Bernard LeBlanc, Stephen D Petersen, Jack Orr, Natalie R Reinhart, Steven H Ferguson
Although predators influence behavior of prey, analyses of electronic tracking data in marine environments rarely consider how predators affect the behavior of tracked animals. We collected an unprecedented dataset by synchronously tracking predator (killer whales, [Formula: see text] = 1; representing a family group) and prey (narwhal, [Formula: see text] = 7) via satellite telemetry in Admiralty Inlet, a large fjord in the Eastern Canadian Arctic. Analyzing the movement data with a switching-state space model and a series of mixed effects models, we show that the presence of killer whales strongly alters the behavior and distribution of narwhal...
March 7, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28203032/icelandic-herring-eating-killer-whales-feed-at-night
#19
Gaëtan Richard, Olga A Filatova, Filipa I P Samarra, Ivan D Fedutin, Marc Lammers, Patrick J Miller
Herring-eating killer whales debilitate herring with underwater tail slaps and likely herd herring into tighter schools using a feeding-specific low-frequency pulsed call ('herding' call). Feeding on herring may be dependent upon daylight, as the whales use their white underside to help herd herring; however, feeding at night has not been investigated. The production of feeding-specific sounds provides an opportunity to use passive acoustic monitoring to investigate feeding behaviour at different times of day...
2017: Marine Biology
https://www.readbyqxmd.com/read/28126344/characterization-and-longitudinal-monitoring-of-serum-androgens-and-glucocorticoids-during-normal-pregnancy-in-the-killer-whale-orcinus-orca
#20
Todd R Robeck, Karen J Steinman, Justine K O'Brien
The secretory patterns of testosterone (T), androstenedione (A4), dehydroepiandrosterone (DHEA), cortisol (C), and corticosterone (Co) were characterized throughout 28 normal pregnancies until two-months post-partum in eleven killer whales. Effects of fetal sex, dam parity or age, and season were evaluated across either day post-conception (DPC), stage of pregnancy (PRE, EARLY, MID, LATE, POST) or indexed month post-conception (IMPC) using a mixed model linear regression with animal ID and pregnancy number as the random variables...
January 23, 2017: General and Comparative Endocrinology
keyword
keyword
94945
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"