Sunday, May 17, 2015

Cum On Feel The Noize

Dead Fin whale in Vancouver harbour - photo by Belle Puri
A fin whale arrived in Vancouver harbour last weekend but unfortunately it was already dead when it was discovered floating around the docks. According to officials it had been struck by a luxury cruise ship somewhere off the northern end of Vancouver Island, and carried all the way back on the bow of the boat. Ironically, this cruise ship, Seven Seas Navigator, bills itself as a wildlife sightseeing vessel that takes passengers on tours in the waters between Vancouver Island and Alaska.

Seven Seas Navigator
Strange as it may seem this is apparently the 3rd time since the 1990's that a fin whale has been dragged like this into the Vancouver harbour and you wonder how many other whales have been hit and simply sank or washed ashore. While I appreciate the difficulty captains of these large ships have in avoiding objects not in their size class you would think something as large as a fin whale would show up on their sonar before they collided and that someone would have noticed a whale stuck on the bow as they cruised along. After all a fin whale is the second largest animal after the blue whale and grows to a length of over 80 feet.

Fin whale on the surface
Conversely, how is it these gentle giants aren't able to stay out of the way of a cruise ship? Long and sleek, these baleen whales are often referred to as the "greyhound of the seas" for their shape and speed which can exceed 20 knots. Like so many other species of whales they were hunted nearly to extinction (after close to a million had been killed) until the 1975 ban on whaling came into effect and, while they have since somewhat recovered to a worldwide population of around 100,000 they are still considered an endangered species.

Fin whale under water
Perhaps the most logical answer is the unfortunate whale didn't even hear the ship coming and just happened to be in the wrong place while taking a nap.  There's growing evidence the increase in ocean noise from modern shipping and naval activity is affecting the hearing of all marine mammals, particularly whales, and even affecting their ability to mate. Fin whales in particular transmit long, low frequency mating calls that in earlier times could be heard thousands of miles away under water but are now reduced to a much shorter distance due to all the background noise in the ocean.

Hearing Damage Chart
Much more serious however is the effect of U.S.& NATO naval sonar testing which is causing death and mass strandings wherever this testing is being conducted.  For humans any noise level over 85 decibels requires hearing protection, 140 decibels causes hearing damage, and at 150 decibels your eardrums would burst. Anything over 185 decibels could kill you, and for marine animals anything over 170 decibels can injure them.  The low frequency active sonar being used by the Navy is 250 decibels and carries for hundreds of miles. The navy has acknowledged this sonar testing is responsible for the deaths of whales in the Bahamas, Canary Islands, Tasmania, Hawaii, New Zealand and other places where whales have turned up with massive haemorrhaging around the ears or stranded on beaches.
Dead beaked whale in the Bahamas
Marine animals rely on sound far more than sight, as it's their way of communicating, hunting and mating.  Sound travels 12 times faster and much further through the water than the air and the combination of commercial marine traffic, seismic surveys, and naval activity is creating so much noise the animals can't hear themselves and it's changing their patterns of calling, foraging and migration. If we care about these animals we need to make a more conscious effort to avoid making noise where they live because they don't need to feel it as well.

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