Clue to killer whale cluster
Why do more than 100 gather off WA every year?
2021-05-10
(Press-News.org) A Flinders University researcher has finally fathomed why large numbers of killer whales gather at a single main location off the Western Australian southern coastline every summer.
In a new paper published in Deep Sea Research, physical oceanographer Associate Professor Jochen Kampf describes the conditions which have produced this ecological natural wonder of orcas migrating to the continental slope near Bremer Bay in the western Great Australian Bight from late austral spring to early autumn (January-April).
"The aggregation is connected to the local marine food web that follows from the upwelling of benthic particulate organic matter (POM) in a confined region near the seafloor plateau near the head of the Hood Canyon," says Associate Professor Kampf, from the Flinders University College of Science and Engineering.
But how and why does this feeding aggregation occur?
Detailed modelling of the three submarine canyons in the region has demonstrated how the process favours the Hood Canyon over the adjoining Bremer and Whale canyons.
"We showed that the shape and position of the Hood Canyon on the continental slope enables it to funnel significantly more benthic particles onto surrounding areas, and this is supported by smaller scale undulations which cause the slope upwelling of POM."
Whale watching is a popular pursuit at the Bremer Bay Canyon hotspot, located 70km offshore from Bremer Bay in the Fitzgerald River National Park.
Naturaliste Charters whale watching tour operators in Bremer Bay says the eco-wilderness expeditions over several years have identified more than 275 regular killer whales at the location, between January and April, with this year's aggregation attracting some new animals.
"This large aggregation of killer whales at Bremer Bay come to the same confined region every year over a seafloor plateau near the head of the Hood Canyon where the total water depth is between 800m and 1000m.
The hydrodynamic modelling framework of the 'Orca Plateau' explains how the Hood Canyon produces a concentrated flow of POM at great depth that provides the diet for deep-sea crabs, squids and other filter feeders upon which killer whales feed.
"Explaining the feeding aggregation of these populations is an important step forward in explaining this natural phenomenon," he says.
The Naturaliste Charters website says: "Every year in summer, this newly discovered remote marine wilderness hot spot off the WA coast becomes the epicentre for an unbelievable intensity of life, including whaler sharks, giant squid, sperm whales, masses of sea birds and the largest aggregation of killer whales in the Southern Hemisphere".
INFORMATION:
The paper, Modelling of physical drivers of a large feeding aggregation of killer whales (Orcinus orca) in the western Great Australian Bight, Australia (2021) by Jochen Kämpf has been published in Deep Sea Research Part 1: Oceanographic Research Papers (Elsevier) Vol 171 DOI: 10.1016/j.dsr.2021.103526
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-05-10
A novel approach to immunotherapy design could pave the way for new treatments for people with an aggressive form of brain cancer called glioblastoma.
Using specifically designed receptors, researchers were able to completely clear brain cancer tumours in preclinical models, using chimeric antigen receptor (CAR) T cell therapy.
Published today in Clinical & Translational Immunology and led by Associate Professor Misty Jenkins, the research is a crucial step towards developing new immunotherapy treatments for this devastating illness.
More than 1800 Australians are diagnosed with brain cancer every year. ...
2021-05-10
A new micro-light-emitting diode (micro-LED) developed at KAUST can efficiently emit pure red light and may help in the quest to develop full-color displays based on just a single semiconductor.
Micro-LEDs are a promising technology for the next generation of displays. They have the advantage of being energy efficient and very small. But each LED can only emit light over a narrow range of colors. A clever solution is to create devices that combine many different LEDs, each emitting a different color. Full-color micro-displays can be created by combining red, green and blue (RGB) micro-LEDs. Now, a KAUST team of Zhe Zhuang, Daisuke Iida and Kazuhiro Ohkawa have worked to develop ...
2021-05-10
SAN FRANCISCO, CA (May 10, 2021) -- The Gulf of Guinea islands harbor an abundance of species found nowhere else on Earth. But for over 100 years, scientists have wondered whether or not a population of limbless, burrowing amphibians--known as caecilians--found on one of the islands is a single or multiple species. Now, a team of researchers from the California Academy of Sciences and the Smithsonian National Museum of Natural History has contributed the strongest evidence to date that there is not one, but two different species of caecilians on São Tomé ...
2021-05-10
Computer scientists at the University of California San Diego have developed a more accurate navigation system that will allow robots to better negotiate busy clinical environments in general and emergency departments more specifically. The researchers have also developed a dataset of open source videos to help train robotic navigation systems in the future.
The team, led by Professor Laurel Riek and Ph.D. student Angelique Taylor, detail their findings in a paper for the International Conference on Robotics and Automation taking place May 30 to June 5 in Xi'an, China.
The project stemmed from conversations with clinicians over several years. The consensus was that robots would best help physicians, nurses and staff ...
2021-05-10
An international team led by researchers from the Xinjiang Institute of Ecology and Geography (XIEG) of the Chinese Academy of Sciences and the University of Geneva has found that flash floods may triple across the Earth's "Third Pole" in response to ongoing climate change.
Their findings were published in Nature Climate Change on May 6.
The Hindu Kush-Himalaya, Tibetan Plateau and surrounding mountain ranges are widely known as the "Third Pole" of the Earth. It contains the largest number of glaciers outside the polar regions.
Due to global warming, the widespread and accelerated melting of glaciers over ...
2021-05-10
Remote quantum distribution on the ground is limited because of the loss of photon in optical fibers. One solution for remote quantum communication lies in quantum memories: photons are stored in the long-lived quantum memory (quantum flash drive) and then quantum information is transmitted by the transportation of the quantum memory. Given the speed of aircrafts and high-speed trains, it is critical to increase the storage time of the quantum memories to the order of hours.
In a new study published in Nature Communications, a research team led by Prof. LI Chuanfeng and Prof. ZHOU Zongquan from University of Science and Technology of China (USTC) extended the storage time of the optical memories to over one hour. It broke the record of one minute achieved by German researchers in 2013, ...
2021-05-10
Chinese researchers achieved 51.5dB nonreciprocal isolation in the atomic ensemble, which is the highest isolation ratio in the non-magnetic nonreciprocal field. They discussed the quantum noise problem in nonreciprocal devices for the first time.
The result was published on Nature Communications on April 22, 2021.
Nonreciprocity is an important basic concept in the optical field. The isolators and circulators derived from it are all indispensable components in the optical path. Faraday isolator based on circular birefringence of magneto-optical effect is widely used because of its easy construction, high isolation and low loss.
However, in the integrated optical path, the traditional faraday isolator is subject to various limitations. ...
2021-05-10
COLUMBUS, Ohio - Watching meaningful films - those that we find moving and poignant - can make us feel more prepared to deal with life's challenges and want to be a better person, a new study found.
The findings point to one reason why people may choose to see movies that make them sad as well as happy and that may explore difficult subjects that aren't always uplifting.
Researchers found that when people recalled watching meaningful films like The Shawshank Redemption and Up, they reported a variety of positive reactions, such as being better able to accept the human condition and make sense of problems in life.
Those positive experiences were less likely to be reported when people thought about watching Hollywood fare like The Big Lebowski or Catch Me ...
2021-05-10
TAMPA, Fla. (May 10, 2021) -- Blocking the fat-busting enzyme lipoxygenase with a synthetic inhibitor throws the immune system's innate inflammatory response out of whack, compromising cardiac repair during acute heart failure, USF Health researchers found.
Their new preclinical study was published April 13 in Biomedicine & Pharmacotherapy.
Acute heart failure - triggered by a heart attack, severely irregular heartbeats, or other causes -- occurs suddenly when the heart cannot pump enough blood to meet the body's demands.
Following a heart attack or any cardiac injury, signals to immune cells called leukocytes ...
2021-05-10
WASHINGTON - A neurologic pathway by which non-damaging but high frequency brain impact blunts normal brain function and causes long-term problems with learning and memory has been identified. The finding suggests that tailored drug therapy can be designed and developed to reactivate and normalize cognitive function, say neuroscientists at Georgetown University Medical Center.
The investigators, working with collaborators at the National Institutes of Health, had previously found that infrequent mild head impacts did not have an effect on learning and memory, but in their new study, reported May 10 in Nature Communications (DOI: 10.1038/s41467-021-22744-6), the investigators found that when the frequency of these ...
LAST 30 PRESS RELEASES:
[Press-News.org] Clue to killer whale cluster
Why do more than 100 gather off WA every year?
