Being more a river dog than an ocean dog, it took a while to provoke my interest – it’s hard for a dog to know what to do with the ocean other than bite a few waves and chase them when they go out, whereas the river has a steady sense of purpose about it.
I mean, there’s a soft murmur to the river, with the odd slap of a carp breaking the surface, but little noise other than the kingfishers’ five-note call, the bee-eaters’ trilling and the dollar birds’ rattling. With the cockies always happy to bring on the full orchestra, of course.
Up on the Kimberley coast, where The Boss likes to head now and then, it’s an altogether noisier place. The tides are huge, up to 11 metres, so there’s a constant rush of water and waves except on the ebb, the fuss of hordes of birds feeding on baitfish, and frenzied eruptions when a croc, or a shark, or a barra targets lunch.
But what he’s always remarked on are the whale songs on a calm night. They ring across the water, echoing and chiming in happy conversation as the humpbacks escort their calves up the west coast on their annual adventure.
Up to 45,000 humpback whales make the migration every winter, leaving the cold waters of the Southern Ocean in favour of the warm nursery waters of Exmouth Gulf and the Kimberley.
They make these intriguing sounds not just to communicate but to eco-locate, to find their way and to find food.
But the whales, it turns out, are having to adapt their calling because there’s plenty of competition these days. There’s more than 50,000 merchant ships thundering across the oceans, alongside another 360 large cruise ships, all of which make a high-pitched ding, plus innumerable smaller fishing boats, trawlers, pleasure craft — plus naval ships and submarines adding to the load.
Then there’s the ear-splitting explosions caused by seismic surveys hunting for oil and gas, with industrial air guns firing their blasts every 10 to 15 seconds, relentlessly for months on end.
Add to that the actual drilling for oil and gas, the sounds of sonar — which can be as loud as an underwater volcano — the construction of offshore wind farms and the laying of pipelines and cables.
These sounds can travel a long way underwater. In the 1960s, an experiment involved setting off an underwater explosion off the coast from Perth, which was detected in Bermuda, 20,000km away.
After the introduction of more powerful sonar technologies back then, the incidence of beached whales went up significantly. Scientists have discovered that some whale species have modified their calls, singing louder and at different frequencies to be better heard over the deep ocean clatter.
They also recorded how, after the Twin Towers attacks of 9/11 in New York, international shipping was virtually halted for a time and the regularly tested faecal matter from whales immediately showed less stress markers.
In Europe, the EU is seeking ways to quieten the oceans, with better-designed ship propellers that issue less noisy turbulence and new sonar technologies that are quieter.
I like the idea that the whales will be able to keep singing. Woof!
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