It is hard to believe that not solong ago, such remains were so rare that biologists refused to believe in theexistence of such creatures except for the secondary evidence caused by scaringon their chief predator, the sperm whale. That is obviously no longer much of a problem.
We are reaching the point inwhich we will have ubiquitous deep sea vessels able to provide a wind shieldlike view and associated lighting. Asonic gun can be also useful in killing specimens and allowing their recovery. The real problem is bringing such specimensto surface without the tissue exploding.
I am expecting a fairly dramaticera of deep sea discovery once that happens as a whole new world of speciesfrom the deep is discovered. I expect tosee the famous sea serpent down there. In particular.
Giant Squid Killed by Sound?
"We now have proof" sonar blasts can harm squid, expert says.
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Workers recover the remains of a female giant squid in Spain 's Asturias
Photograph by Fernando Camino, Cover/Getty Images
Ker Than
Published May 3, 2011
When giantsquid were found dead off Spain abouta decade ago, scientists suspected that powerful sound pulses from ships hadharmed the animals. Now the evidence may be in.
A new study says low-frequency sounds from human activities can affectsquid and other cephalopods, not just whales and other marine mammals, whichhave long been thought to be vulnerable to such pulses. (See "U.S.Navy Sonar May Harm Killer Whales, Expert Says.")
The finding suggests noise pollution in the ocean is having amuch broader effect on marine life than previously thought, said study leaderMichel André, a marine bioacoustician at Barcelona's Technical University of Catalonia.
"We know that noise pollution in the oceans has a significantimpact on dolphins and whales [which use natural sonar to navigate and hunt].... but this is the first study indicating a severe impact on invertebrates, anextended group of marine species that are not known to rely on sound forliving," André said in a statement.
Giant Squid Mystery Solved?
In the early 2000s the remains of giant squid were found off Spain 's Asturiasprovince (map). In each case, the creatures' bodies appeared soon afterships had used air guns to conduct low-frequency sound-pulse exercises in theregion, in some cases for oil-and-gas prospecting efforts.
Scientists investigating the giant squid remains at the time foundevidence of extensive bodily damage, including mantles reduced to pulp, bruisedmuscles, and lesions in statocysts. These fluid-filled organs rest behind thecreatures' eyes and help giant squid maintain balance and position. (See picturesof a colossal squid dissection.)
At the time, marine biologist Angel Guerra speculated—but was unable toprove—that noise from prospecting ships was harming cephalopods and othermarine life.
"With this study, we now have proof" that low-frequencysounds can harm cephalopods, said Guerra, a marine biologist at Spain's Marine Research Institute who was notinvolved in the current study, which will appear in a future issue of thejournal Frontiers in Ecologyand the Environment.
Damage Worsened With Time
During the study, the research team examined the effects oflow-frequency sound exposure in 87 individual cephalopods belonging to fourspecies: two species of squid, one species of octopus, and one species ofcuttlefish. (See"CuttlefishChange Color, Shape-Shift to Elude Predators.")
For two hours the animals were exposed to sound with intensities ofbetween 157 and 175 decibels and frequency ranges of 50 to 400 Hertz.
These frequencies and intensities "are commonly found in the noiseproduced by many activities at sea," such as military sonar tests orefforts to detect oil and natural gas by gauging the nature of material beneaththe seabed, the Technical University of Catalonia's André told NationalGeographic News.
After the sound exposure, the scientists killed the animals, eitherimmediately or up to 96 hours afterward.
The animals that were killed immediately after exposure showed signs ofdamage to their statocyst tissue. Specifically, tiny hairlike structures instatocyst cells—which bend as the cephalopods move through water and help theanimals balance—were lost, essentially crippling the creatures.
The animals allowed to live longer showed further damage, includinglarge, visible holes in the statocyst tissue.
"This is a typical process found in land mammals and birds afteracute noise exposure: a massive acoustic trauma followed by peripheral damage,making the lesions worse over time," André said.
In their final seconds or hours, the test cephalopods "moved alittle bit, but they were not swimming, eating, or mating," André said.
A separate group of about a hundred cephalopods was not exposed to thepulses. They remained healthy and behaved normally.
Both groups had been kept in the same aquariums before being separated,and all the animals had behaved normally before the tests—ruling out thepossibility that the damage observed in the test group was due to captivity orhuman handling, he said.
("Raise the Alarm" for Giant Squid?
Though the cephalopods in the experiments were much smaller than giantsquid, the experiments represent "the same phenomena as with the giantsquid," the Marine Research Institute's Guerra said.
The test animals are appropriate stand-ins for their giant squidcousins, according to Guerra, who said he sees no reason why the findingswouldn't apply to giant squid.
There are some differences in the damage, though.
The injuries to the giant squid found last decade, he noted, were muchmore pronounced than in the experimental animals. Guerra attributes this to thehigher acoustic intensities and multiple sound sources giant squid are exposedto in the real world.
And of course, the giant squid were found not just injured but dead,unlike the test animals. But scientists say the case of the giant squid off Spain
At the time of the giant squid deaths, "we hypothesized that thegiant squid died in one of two ways: either by direct impact from the soundwaves or by having their statocysts practically destroyed and [the squid]becoming disoriented," Guerra explained.
"The disoriented animals might wander up from the depths to thesurface, where the temperature difference kills them."
Marine zoologist Michael Vecchione, of the U.S.
Though the new research presents enough evidence to "raise thealarm," more studies are necessary before a solid case can be made thathuman-caused noise pollution is causing pervasive damage to marine life, saidVecchione, who also did not participate in the study.
But, he added, "the evidence is accumulating that what [Guerra]first proposed based on the giant squid might actually be correct."
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