Northern Pacific Sound Pollution
College of the Atlantic GIS Winter '23
The Speed of Sound
Sound travels at 343 meters per second. In the water, sound moves at 1,500 meters per second! While this can differ based on water temperature and surroundings, sound still moves over 4 times as fast than on land.
The longest distance a human shout has been heard from is just over 10 miles, and that scream happened over a lake. Researchers have estimated that a whale scream, or more so a song, can be heard from over 10,000 miles away! Though we can't always hear these songs because of their low frequencies, whales can listen and respond to each other from oceans away.
Take a look at the map below. The pink points are all oil rigs and wells on the West Coast and the Gulf. It is important to keep in mind that though there are many sound polluters shown, the points are only from two datasets. Imagine how pink the coast would be if every rig recorded was presented! Note that the oldest of these rigs has been installed since 1967.
Oil Rigs on the West Coast and Gulf of Mexico
Oil Rigs and Wells Sound Rings
The map above shows mileage rings around the rigs and wells. The inner most ring, the muted green, is 25 miles out. Light green is 50 miles, light blue is 75 miles, and muted blue is 100 miles. While 100 miles may seem far from a source of sound, to whales it's like yelling in their ears! Remember that a whale call can travel 10,000 miles. Imagine how frustrating the sound of drilling would be with hearing that sensitive.
Migration
Whales migrate seasonally for food and mating. While not all whales follow this pattern, it can generally be said that whales move to cooler water in the summer months for food and migrate towards warmer water in the winter to mate and birth offspring. Most pods return to the same areas each year.
The map below shows blue whale sighting from 1993 to 2008. Click the play button to watch their movement, and note that these points are only sightings. Whales still migrate even when we aren't looking!
Rigs and Whales
Sound Pollution
Take a look at these maps combined. Do you notice anything about sound impacting the whales?
Based on the data in these maps, it is not obvious that the whales are skirting around the sound. Why might that be?
Think back to the first map shown. The first of the rigs and wells in the data was installed in 1967, and these specific whales were sighted starting in 1993. Do you think the whales have gotten accustomed to the noise? Maybe the datasets just are not comprehensive enough for the issue at hand? Or perhaps benefits in those areas outweigh the noise?
Focus on the West Coast of North America in this map showing phytoplankton concentrations. Notice the darker blue near the coast compared to more north. How do whales place value on their resources versus their comfort? Do you think food concentration is more important to whales than sound?
Moving Forward
The link between humans and marine life is one that has been ignored for far too long. Good news, though- this is changing! More organizations and policy makers are taking note of the impact humans have than ever. Click through the slides below to learn about current and upcoming policy!
