Field Work

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Whales are using more energy to communicate

There is a rising din in the oceans - and the whales are struggling to compete with them.

"you're only wasting more time and energy trying to communicate... in essence, by shouting at each other-what we have to do in a night club," explains Mark Jessopp says the University College Cork.

Dr Jessopp was recently on a Research project to study the impact of marine seismic surveys on animals, such as whales and dolphins.

He and his colleagues found a "huge decline" in sightings of such species, if The Work was going on, even when accounting for other factors, such as the Weather .

Mark Jessopp, studies carried out on the effects of seismic surveys on sealife

Seismic investigations by a number of organisations, including the oil and gas companies, as a means of mapping what lies beneath the sea floor.

The Waves , fired from an air rifle, as a very powerful Speaker - blasted down to the bottom of the sea. The Waves bounce off features are below, and detected again at The Surface . The Signal returns, reveals, whether it is, for example, oil, locked up in The Rock .

The Process generates a huge noise. "It is Like an explosion," says Lindy Weilgart of Dalhousie University in Nova Scotia . She says that there is now sufficient evidence to show that many marine species are negatively affected by the shouting.

Quieter tech is not to be fast enough, says researcher Lindy Weilgart

The implications are not only mammals such as whales and dolphins felt, she adds. Fish and invertebrates such as crabs have also been seen to change their behaviour, if the noise level is on the rise. You can see feeding or less will be placed in the location to predators, for example.

And a technology exists that could be far harmful less. It is called marine vibroseis, and it is a low-energy alternative to air-to-air weapons. Instead of explosive blasts, vibroseis smaller vibrations are used to transmit waves to the bottom of the sea. In fact, a similar amount of energy radiates total, but spread over a longer period of time, i.e. the survey has a less "shocking" effect.

Stephen Chelminski, who invented the seismic gun in the late 1950s, has become a supporter of the vibroseis because of its perceived benefits for the environment.

Dr. Weilgart says, there are many efforts to the commercialization of this quieter tech, but she is unimpressed as you are. "It's just crawling at a snail's pace is progress," she says.

Shell , Total and Exxonmobil have spent years in the development of new seismic tech

Three of The World 's largest oil companies, Shell , Total and Exxonmobil -years spent on the development of a marine vibroseis. Andrew Feltham, a geophysicist at the sum, The Work on The Project , says that The System has been shown to work as designed, but requires some more testing before it can be used in the field.

He says that an advantage of the prototype-is not The Device that produce noise, over a wide range of frequencies.

"We radiate energy only in the frequency band of interest for The Work at hand," he explains. This reduces The Number of sea animals that you hear noise would be generated by The Device , lower the environmental impact.

the Norwegian company Petroleum Geo-Services (PGS), which helps oil and gas companies, the offshore reserves of fossil fuels, has also been working on a vibroseis system. It has a different, more compact design uses a stack of plates create vibrations.

the Research shows, dolphins and other sea animals avoid areas where seismic surveys are in progress

This allows the production of a strong seismic signal but prevents The Device from shaking apart.

"through the stacked plates is an ingenious solution," argued the Bard Stenberg, a spokesman for the PGS.

The prototype out of a 1,000-hour test in a container filled with water and depths of 60m (197ft) has to hold in a port. However, it is yet to be tested out on the sea.

Nathan is a merchant, a bioacoustician at the UK Centre for Environment Fisheries and Aquaculture Science (Cefas). He says that the vibroseis would actually be a better technique for companies to survey the seabed, because it can be more fine tuned. And yet, commercial interest, it has not proved to be true really.

"This is one of the areas in which we need a little bit of pressure from the policy and regulation for the page to create a market for this type of technology," he argues.

A map of the noise of the sea around the UK - Red is the loudest and blue the softest,

Dr. Kaufmann's study of noise pollution in the seas around the UK. He and his team recently completed a detailed map of where the cacophony is at its greatest. However, while it is difficult to confirm exactly how the noise have said in the last few decades, it, you, probably, have increased, in total.

"The Answer is almost certainly" Yes," he says.

He pointed out that there are other significant sources of noise pollution on the lake. To noise by the ship's journey, where, for example, the Propeller cutting through the water, creating a Wake-and with a mighty rumble that can travel for hundreds or even thousands of kilometers.

Then there are offshore wind farms, which rely on pile-driver to create bash huge columns in the sea ground, The Base platform for the turbines. Engineers that are left on such projects to clear unexploded ordnance, for example from the second World War .

the detonation of a Bomb under water creates a lot of noise, but the Pony can be tempered to to create by a device to blow a curtain of air around The Bomb .

The construction of offshore wind farms generates a lot of noise for sealife

wind farms in great Britain bubble curtains for this purpose, licensed to include Hornsea One and Two from the North-East coast. Currently Under Construction , the full Hornsea complex finally, the largest offshore installation in The World .

marine biologists continue to hope for a technology, human activity in the oceans quieter. Dr Jessopp acknowledges that the seismic air-guns are cheap and have been proven to work. Marine vibroseis is not yet available on a commercial scale, companies can not see no reason to change how they do things.

"In The Absence of a real viable alternative, we have kept just to do it. It is a kind of "business as usual", says Dr Jessopp.

So the seas will stay loud for once, and the whales have to shout to be heard.

environment, whales, oceans, dolphins

Source of news: bbc.com