A spotlight has recently been shone on the South African Navy’s underwater explosions in False Bay during the peak of the whale season. The Navy believes that the official Southern Right whale season runs from August to November but recent studies show that it is somewhat longer than this.
The Southern Right whales arrive off our coast from May onward and generally leave by Christmas. This provides a window of around four months when the relatively low numbers of whales make it safer to test explosives deemed vital to naval preparedness. Whale experts have also recently established that some whales remain in our waters for much of the year, feeding off St Helena Bay on the West Coast. Whatever the situation, as whale numbers increase and the season lengthens, management practices must be constantly reassessed to establish a sustainable programme of managing this massive tourist resource and to make our waters safe for our cetacean cousins.
But it isn’t only naval explosions that carry risks to whales: an omnipresent global danger is from naval sonar. Sonar (SOund Navigation And Ranging) can be compared to underwater radar, with one big difference. It does not use radio waves, relying instead on sound; lots of it. Sonar was first developed during WWII to locate submarines and other submerged dangers. It has since evolved significantly over last 50 years. Modern naval sonar systems are extremely powerful and loud and have been proven to have a detrimental effect on whales and dolphins. At the International Whaling Council (IWC) meeting in Rome during July of this year, the IWC scientific committee released a report demonstrating a clear relationship between the use of sonar and whale strandings. It stated; “There is now compelling evidence implicating military sonar as a direct impact on beaked whales in particular.”
“This is the first time such a broad, diverse group (of scientists) has made this finding,” said environmental lawyer Joel Reynolds. “Navies of the world do back-flips to deny any connection.”
This relationship has been established by correlating numerous strandings where naval exercises have occurred. Events in Hawaii, the Bahamas, Greece, US West Coast and many other areas of the world have backed this up. While deep diving ‘beaked’ whales have been found to be the most susceptible to sonar noise, many other species are also affected, and our understanding of this problem is far from complete.
In March 2000, 28 common dolphins stranded near Port Elizabeth, in what was the biggest mass stranding around our coast in almost 20 years. Four days prior to this stranding an international naval task force passed through the area.
While our Navy may have good intentions, many other navies, particularly the US Navy, have worked hard to remove protection for marine mammals from the effects of sonar.
A worrying new development is the deployment of a new type of sonar known as Low Frequency Active Sonar (LFAS)
LFAS is used to seek and identify the new silent submarines developed by various navies. This sonar produces some of the loudest noises ever made by humans, at over 260 decibels. A jet taking off generates about 120 decibels. The US environmental protection group, the Natural Resources Defense Council (NRDC) has secured a legal injunction to limit the use of LFAS and has now targeted the more common mid-frequency sonar that was probably responsible for the Port Elizabeth and many other strandings.
Sound travels further in water than in air. An experiment in 1991 showed that underwater noises generated off the aptly named Heard Island (located in the Southern Ocean between Australia and South Africa) were detected on both the east and west coasts of the USA, on the opposite side of the world.
The real danger of LFA Sonar is not only its intensity but also its range. If the proposed system is fully deployed, approximately 80% of the world’s oceans will be at risk. Ocean sanctuaries will become meaningless concepts.
This is all directly relevant to South Africa. Given our increasingly close relationship with US armed forces, coupled to our strategic position, there is a good chance that our further naval co-operation will be called upon. We occupy a key position on the sea-lane that carries the majority of the world’s oil between the Persian Gulf and Europe and the USA.
As is evident by recent US global re-positioning in the Middle East and central Asia, that nation clearly has few qualms about the lengths to which it will go to protect its addiction to oil.
Most whale species are not nearly as threatened by the high profile whaling activities of a few rogue nations as they are to this increasing threat from naval sonar. Sonar not only kills or disorientates whales them but also negatively impacts their communication and migration. We must, as the guardians of our environment ensure that both low and medium frequency sonar is not allowed to be deployed in our waters.
It is important that we fulfil our obligations to protect whales from this horrendous modern threat. As whale expert and educator Noel Ashton says, “Imagine having a strobelight flashing before your eyes as you try to live a normal existence. It simply is not possible.” That is pretty much what whales will experience with this disruption to their primary sense, sound.
If our navy is planning to deploy high power mid- or low-frequency sonar capability in our new frigates and submarines, it is essential that a full environmental impact assessment (EIA) be undertaken. Our armed forces must be held responsible for their actions and although our defence is important, there is little real threat to our marine sovereignty, unless we plan on blasting the ears of perlemoen poachers or torpedoing their vessels?
The most real threat to our whales is not so much occasional explosions but that of the uncontrolled deployment of powerful naval sonar, both locally and internationally. We certainly cannot allow LFAS to be used here or for ourselves to become party to its international use. We must find out if our navy is considering its use. If any of these types of sonar are to be deployed on our new frigates and submarines, then a process of open consultation must occur so we can take steps to protect the whales and dolphins in our waters.
In the 1970s and 80s, we brought a stop to international whaling. We have shown we can manage to protect these magnificent creatures and in the 21st century it is our task to act on their behalf again.