Ship Noise a Problem for Killer Whales

March 22, 2016

Unlocking Word Meanings

Read the following words/expressions found in today’s article. 

1. verify / ˈvɛr əˌfaɪ / (v.) – to prove to be true
Example: The scientist designed an experiment to verify his ideas.

2. elevate ˈɛl əˌveɪt / (v.) – to increase or raise
Example: Stress levels among the team members elevated as the deadline approached.

3. starvation / stɑrˈveɪ ʃən / (n.) – state of extreme hunger
Example: It was unlikely to see animals die of starvation in that area.

4. pollutant / pəˈlut nt / (n.) – something that destroys a natural resource
Example: The river near the factory is full of pollutants.

5. pace peɪs / (n.) – the rate of movement of someone or something
Example: I got sleepy during the movie because the pace was too slow.


Read the text below.
A study found that noise from ships disrupts the communication and prey-tracking abilities of killer whales.

While low-frequency noise affects the whales, it is in the higher frequencies that their communication and echolocation abilities, or the ability to track prey through sounds, is most affected. The study verified that ship noise is also present at 20,000 hertz, or the frequency where killer whales hear well.

By measuring about 1,600 ships passing through Haro Strait, a habitat for Southern Resident Killer Whales in Washington State, scientists determined that the ships elevate background noise at higher frequencies. This has the negative effect of interfering with the animals' communication and echolocation abilities, which are essential to their survival and predatory behavior.

Normally, killer whales seek out their prey, chinook salmon, using echolocation. However, loud ship noise makes echolocation more difficult, thereby increasing the chances that the whales would starve. Starvation forces whales to rely on excess blubber, or the fat under their skin so they can function. This can be dangerous to the whales if their blubber is contaminated with pollutants, which can lead to poisoning when released to the whales’ body.

While these negative effects caused by ship noise have been established, scientists still push for more research into the effects of ship noise on killer whales.

The study also revealed two possible solutions to the ship noise problem. First, the technology which enables military ships to be quieter than commercial ships may be used to develop less noisy commercial ships. Second, ships may switch to a slower pace, as this enables ships to be less noisy.

Viewpoint Discussion

Enjoy a discussion with your tutor.  

Discussion A 

·         How else do you think ships negatively affect marine life?
·         What are other man-made threats to marine life?

Discussion B

·         What other modes of transportation have an impact on the environment?
·         Do you think pollution cannot be separated from technology? Why do you think so?

March 22, 2016