In recent years, there has been concern that man-made noise may be a cause of stress for dolphins, whales and other marine mammals, but the results of a five-year study show that noise pollution – especially noise generated by seismic airguns during geophysical exploration for oil and gas – seems to have minimal effect on endangered sperm whales in the Gulf of Mexico, say researchers from Texas A&M University who led the project and released their 323-page report today at the Houston Museum of Natural Science.
The multi-year $9 million study, the largest of its type ever undertaken and formally titled Sperm Whale Seismic Study in the Gulf of Mexico, was conducted by the Minerals Management Service and featured cooperation with the Office of Naval Research, the National Science Foundation and the National Fish and Wildlife Foundation. The project brought together researchers from eight universities, but it was managed overall by Texas A&M's Department of Oceanography, with research scientist Ann Jochens and professor Doug Biggs serving as principal investigators.
"The bottom line is that airgun noise from seismic surveys that are thousands of yards distant does not drive away sperm whales living in the Gulf," Biggs explains.
"However, some individual whales feeding at depth reduced the rate at which they searched acoustically for their prey when scientists carried out controlled exposure experiments by bringing seismic surveys close by the whales. As a result, the oil and gas industry has agreed to a best-practice attitude that seismic surveys should shut down temporarily when towed airguns come within one-third of a mile of whales or groups of whales in the Gulf."
Though not often seen, sperm whales are regular visitors to and residents in the Gulf of Mexico. They are the largest of all toothed whales and can reach lengths of 60 feet or more and live 60 years or longer. Their primary diet is squid and fish and they have been known to dive as deep as 7,000 feet. Humans no longer hunt them for their oil, but the whale in Herman Melville's classic novel Moby Dick was a sperm whale.
Sperm whales are not often seen because they prefer to stay in the deep waters of the Gulf, usually in depths of 3,000 feet or more and at least 150 miles offshore, Biggs says.
"Sperm whales go to where their food source is, and that means very deep water. So folks that do see them are marine mammal observers who ride the seismic survey vessels and the workers on the big oil and gas rigs, and even that does not happen often," Biggs adds.
The primary concern facing the scientific research group was noise – there's more of it in the world's oceans than you might think. A study by the Scripps Institution of Oceanography shows that the world's oceans are 10 times noisier since the 1960s, and at any one time, there are as many as 30,000 ships circling the globe.
Biggs says that over the course of five summers, 98 sperm whales were tagged with devices that relayed back critical data such as measurements about sound levels and behavioral aspects of whales, including tracking their movements. Of particular concern was the effect that loud low-frequency noises, such as those created by seismic activity, might have on sperm whales in the area.
Oil and gas companies prospect for subsea reservoirs by firing air guns during their seismic work, which government regulators thought might negatively affect sperm whale behavior. Also, the sheer volume of work being done in the Gulf was another concern: The Gulf of Mexico accounts for almost 70 percent of the oil and gas extracted from U.S. waters and there are thousands of oil and gas platforms in the region.
But the study found no unusual effects of controlled exposure to seismic exploration on the swimming and diving behavior by sperm whales in the Gulf, and also revealed a wealth of data about sperm whale biology and habitat.
"We now know that the sperm whales in the Gulf appear to be their own distinct stock – they show genetic and social differences from other sperm whales around the world," Biggs says.
"There are believed to be about 500 to 1,500 sperm whales that reside in the Gulf. Most of these are family groups of females and maturing young. When one family group socializes with another family group in the Gulf, they make very distinct sounds. Even though the family groups are visited by males that come into the Gulf from other oceans, their 'clicking' sounds, called codas, the Gulf sperm whales make appear to be different from most others made by sperm whale groups in other parts of the world.
"The five-year study has greatly contributed to our knowledge of sperm whales, especially those found in the Gulf of Mexico. It's also raised new questions we need to know more about, such as their feeding and breeding patterns. There's still a lot we don't know about these huge creatures."
Keith Randall | EurekAlert!
Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide
Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences