keyword
MENU ▼
Read by QxMD icon Read
search

Killer whale

keyword
https://www.readbyqxmd.com/read/28275880/cultural-hitchhiking-in-the-matrilineal-whales
#1
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
#2
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...
February 24, 2017: Chemosphere
https://www.readbyqxmd.com/read/28250185/epistatic-interactions-influence-terrestrial-marine-functional-shifts-in-cetacean-rhodopsin
#3
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
#4
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
#5
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
#6
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
#7
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
https://www.readbyqxmd.com/read/28089514/reproductive-conflict-and-the-evolution-of-menopause-in-killer-whales
#8
Darren P Croft, Rufus A Johnstone, Samuel Ellis, Stuart Nattrass, Daniel W Franks, Lauren J N Brent, Sonia Mazzi, Kenneth C Balcomb, John K B Ford, Michael A Cant
Why females of some species cease ovulation prior to the end of their natural lifespan is a long-standing evolutionary puzzle [1-4]. The fitness benefits of post-reproductive helping could in principle select for menopause [1, 2, 5], but the magnitude of these benefits appears insufficient to explain the timing of menopause [6-8]. Recent theory suggests that the cost of inter-generational reproductive conflict between younger and older females of the same social unit is a critical missing term in classical inclusive fitness calculations (the "reproductive conflict hypothesis" [6, 9])...
January 23, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/27923044/killer-whale-orcinus-orca-predation-on-beaked-whales-mesoplodon-spp-in-the-bremer-sub-basin-western-australia
#9
Rebecca Wellard, Keith Lightbody, Leila Fouda, Michelle Blewitt, David Riggs, Christine Erbe
Observations of killer whales (Orcinus orca) feeding on the remains of beaked whales have been previously documented; however, to date, there has been no published account of killer whales actively preying upon beaked whales. This article describes the first field observations of killer whales interacting with, hunting and preying upon beaked whales (Mesoplodon spp.) on four separate occasions during 2014, 2015 and 2016 in the Bremer Sub-Basin, off the south coast of Western Australia.
2016: PloS One
https://www.readbyqxmd.com/read/27908079/using-line-acceleration-to-measure-false-killer-whale-pseudorca-crassidens-click-and-whistle-source-levels-during-pelagic-longline-depredation
#10
Aaron Thode, Lauren Wild, Janice Straley, Dustin Barnes, Ali Bayless, Victoria O'Connell, Erin Oleson, Jit Sarkar, Dan Falvey, Linda Behnken, Sean Martin
False killer whales (Pseudorca crassidens) depredate pelagic longlines in offshore Hawaiian waters. On January 28, 2015 a depredation event was recorded 14 m from an integrated GoPro camera, hydrophone, and accelerometer, revealing that false killer whales depredate bait and generate clicks and whistles under good visibility conditions. The act of plucking bait off a hook generated a distinctive 15 Hz line vibration. Two similar line vibrations detected at earlier times permitted the animal's range and thus signal source levels to be estimated over a 25-min window...
November 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27908070/physical-constraints-of-cultural-evolution-of-dialects-in-killer-whales
#11
Olga A Filatova, Filipa I P Samarra, Lance G Barrett-Lennard, Patrick J O Miller, John K B Ford, Harald Yurk, Craig O Matkin, Erich Hoyt
Odontocete sounds are produced by two pairs of phonic lips situated in soft nares below the blowhole; the right pair is larger and is more likely to produce clicks, while the left pair is more likely to produce whistles. This has important implications for the cultural evolution of delphinid sounds: the greater the physical constraints, the greater the probability of random convergence. In this paper the authors examine the call structure of eight killer whale populations to identify structural constraints and to determine if they are consistent among all populations...
November 2016: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/27870149/development-of-sociality-and-emergence-of-independence-in-a-killer-whale-orcinus-orca-calf-from-birth-to-36-months
#12
Sara Guarino, Heather M Hill, Julie Sigman
Dolphin calves spend most of their time swimming with their mother immediately after birth. As they mature, the calves become increasingly independent, and begin to interact more often with other calves, juveniles, and sub-adults. For bottlenose dolphin calves, sociality is related to maternal behaviors. Unfortunately, much less is known about the development of sociality and emergence of independence for killer whale calves. The purpose of this study was to examine the developmental changes in social behaviors and solitary activities of a killer whale calf across a 36-month period...
January 2017: Zoo Biology
https://www.readbyqxmd.com/read/27804965/killer-whales-differentiating-in-geographic-sympatry-facilitated-by-divergent-behavioural-traditions
#13
A R Hoelzel, A E Moura
No abstract text is available yet for this article.
December 2016: Heredity
https://www.readbyqxmd.com/read/27770983/conservation-status-of-killer-whales-orcinus-orca-in-the-strait-of-gibraltar
#14
REVIEW
R Esteban, P Verborgh, P Gauffier, D Alarcón, J M Salazar-Sierra, J Giménez, A D Foote, R de Stephanis
Killer whales (Orcinus orca) in the Mediterranean Sea are currently restricted to the Strait of Gibraltar and surrounding waters. Thirty-nine individuals were present in 2011, with a well-differentiated social structure, organized into five pods. Killer whale occurrence in the Strait is apparently related to the migration of their main prey, Atlantic bluefin tuna (Thunnus thynnus). In spring, whale distribution was restricted to shallow waters off the western coast of the Strait where all pods were observed actively hunting tuna...
2016: Advances in Marine Biology
https://www.readbyqxmd.com/read/27770981/marine-mammals-in-the-mediterranean-sea-an-overview
#15
G Notarbartolo di Sciara
Despite being a small part of the world's oceans, the Mediterranean Sea hosts a diverse marine mammal fauna, with a total of 28 different species known to occur, or to have occurred, in the region. Species currently recognised as regular in the Mediterranean-the Mediterranean monk seal (Monachus monachus) and 11 cetaceans (fin whale, Balaenoptera physalus; sperm whale, Physeter macrocephalus; Cuvier's beaked whale, Ziphius cavirostris; short-beaked common dolphin, Delphinus delphis; long-finned pilot whale, Globicephala melas; Risso's dolphin, Grampus griseus; killer whale, Orcinus orca; striped dolphin, Stenella coeruleoalba; rough-toothed dolphin, Steno bredanensis; common bottlenose dolphin, Tursiops truncatus; harbour porpoise, Phocoena phocoena relicta) have adapted well to the region's environmental conditions, but their coexistence with humans is problematic...
2016: Advances in Marine Biology
https://www.readbyqxmd.com/read/27636553/androgen-and-glucocorticoid-production-in-the-male-killer-whale-orcinus-orca-influence-of-age-maturity-and-environmental-factors
#16
J K O'Brien, K J Steinman, G A Fetter, T R Robeck
Circulating concentrations of testosterone and its precursor androstenedione, as well as dehydroepiandrosterone (DHEA) and the adrenal hormones cortisol and corticosterone were measured at monthly intervals in 14 male killer whales (Orcinus orca) aged 0.8-38 years. Analyses were performed for examination of the relationships of age, sexual maturation status (STATUS), season, and environmental temperature (monthly air ambient temperature, A-TEMP) with hormone production using a mixed effects linear regression model with animal ID as the random variable...
January 2017: Andrology
https://www.readbyqxmd.com/read/27547372/dietary-habits-of-polar-bears-in-foxe-basin-canada-possible-evidence-of-a-trophic-regime-shift-mediated-by-a-new-top-predator
#17
Melissa P Galicia, Gregory W Thiemann, Markus G Dyck, Steven H Ferguson, Jeff W Higdon
Polar bear (Ursus maritimus) subpopulations in several areas with seasonal sea ice regimes have shown declines in body condition, reproductive rates, or abundance as a result of declining sea ice habitat. In the Foxe Basin region of Nunavut, Canada, the size of the polar bear subpopulation has remained largely stable over the past 20 years, despite concurrent declines in sea ice habitat. We used fatty acid analysis to examine polar bear feeding habits in Foxe Basin and thus potentially identify ecological factors contributing to population stability...
August 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/27536700/comparative-in-silico-study-of-sex-determining-region-y-sry-protein-sequences-involved-in-sex-determining
#18
Masoume Vakili Azghandi, Mohammadreza Nasiri, Ali Shamsa, Mohsen Jalali, Mohammad Mahdi Shariati
BACKGROUND: The SRY gene (SRY) provides instructions for making a transcription factor called the sex-determining region Y protein. The sex-determining region Y protein causes a fetus to develop as a male. In this study, SRY of 15 spices included of human, chimpanzee, dog, pig, rat, cattle, buffalo, goat, sheep, horse, zebra, frog, urial, dolphin and killer whale were used for determine of bioinformatic differences. METHODS: Nucleotide sequences of SRY were retrieved from the NCBI databank...
April 2016: Reports of Biochemistry & Molecular Biology
https://www.readbyqxmd.com/read/27485668/genome-wide-snp-data-suggest-complex-ancestry-of-sympatric-north-pacific-killer-whale-ecotypes
#19
A D Foote, P A Morin
Three ecotypes of killer whale occur in partial sympatry in the North Pacific. Individuals assortatively mate within the same ecotype, resulting in correlated ecological and genetic differentiation. A key question is whether this pattern of evolutionary divergence is an example of incipient sympatric speciation from a single panmictic ancestral population, or whether sympatry could have resulted from multiple colonisations of the North Pacific and secondary contact between ecotypes. Here, we infer multilocus coalescent trees from >1000 nuclear single-nucleotide polymorphisms (SNPs) and find evidence of incomplete lineage sorting so that the genealogies of SNPs do not all conform to a single topology...
November 2016: Heredity
https://www.readbyqxmd.com/read/27401258/characterization-and-longitudinal-monitoring-of-serum-progestagens-and-estrogens-during-normal-pregnancy-in-the-killer-whale-orcinus-orca
#20
Todd R Robeck, Karen J Steinman, Justine K O'Brien
The secretory patterns of progestagens and estrogens were characterized throughout 28 normal pregnancies until two month post-partum in eleven killer whales. HPLC analysis of serum from different reproductive stages (luteal phase, EARLY, MID, and LATE pregnancy) identified three major immunoreactive progestagen peaks; progesterone (P4), 5α-pregnane-3,20-dione (5α-DHP) and pregnanediol, with 5α-DHP approximately half of that for P4 in the luteal phase, and EARLY, but approximately 2/3 of P4 during MID and LATE pregnancy...
September 15, 2016: General and Comparative Endocrinology
keyword
keyword
65414
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"