Noise and wildlife

How a tsunami revealed human noise pollution

 

Photo credit: Calbear22, photo released into the public domain

Phys.org reports how a tsunami that struck Hawaii in 2011–caused by the same earthquake that hit Japan and created the tsunami that triggered the Fukushima nuclear disaster–caused a temporary halt to boat traffic that allowed scientists “a rare glimpse into what the bays might sound like without human activities.” By luck, the tsunami hit while “a Duke University-lead team was recording underwater sound in four bays” on Hawaii’s Kona coat.

It turns out that oceans are pretty loud. On the day of the tsunami, the loudest part of the day reached 98.8 decibels. Why are oceans so loud? “Because sound waves travel and are amplified differently in water than in air.” But 98.8 decibels was quiet compared to a reading on a typical day, as noise from boat traffic can reach up to 125 decibels, and the sound from nearby sonar exercises tops 143 decibels.

So what did the Duke study conclude? It showed that humans created the loudest disruptions and boat traffic and sonar were “significant causes of noise in all four bays.” Human-made noise has long been a concern of conservationists who fear that “interactions caused by dolphin-encounter boat tours and other human activities” are disrupting dolphins’ sleeping behaviors and potentially interfering with their hunt for food, since dolphins rest in the bays during the day to ready themselves for the hunt at night.

How to help pets stressed by fireworks

Yesterday was Bonfire Night in the UK, a time spent with friends and family, lighting bonfires and enjoying fireworks displays. As in the U.S., people look forward to the parties and displays, but they worry about how the noise makes their pets anxious and fearful. Here’s a useful piece from The Warrington Guardian that looks at how pet owners can protect their stressed out pets.

And for more difficult cases, there’s a medicinal treatment to help man’s best friend.

Or we could enjoy the display without the noise and opt for quiet fireworks.  Yes, it’s an option.

Oysters can hear noise

 

Photo credit: Daniel Schwen licensed under CC BY-SA 4.0

and it’s stressing them out! Jean-Charles Massabuau, a marine biologist at the French National Centre for Scientific Research, was working on a different project when a diver noted he had never dived in such a noisy spot. Massabuabu wondered if the oysters in that location could hear the noise. After setting up an experiment to see if they would react (they did!) and how (shutting their shells), Massabuabu and team wrote up their findings. Although the oysters had a way to shut out the noise, it comes at a price–they can neither eat nor breathe when their shells are closed.

There is a well-established body of research about ocean sound, but Massabuabu thinks his study results suggest “we should expand our concerns about the impact of noise pollution beyond today’s focus on only dolphins and whales.”

We agree.

Though we must add that while noise pollution may stress out oysters, it’s probably pales in comparison to waiting to be shucked and served with a side of cocktail sauce.

Study: Female Fish Attracted To Males Who ‘Sing’

but noise pollution kills the mood, writes Calum Mckinney, Study Finds, and it’s disrupting fish reproduction all across the world. Mckinney introduces us to Eva-Lotta Blom, a doctoral student at University of Gothenburg, who says “that a large part of the problem is that beneath the waves, sound travels much farther and almost five times faster than in the air.” One common source of noise is from ships, as the sound travels far from the source, creating a very noisy situation that would not be tolerated on land. But industrial noise from pile driving and “seismic airguns may be a bigger factor in ocean noise pollution.

And, no surprise, there are absolutely no noise regulations governing our oceans.

So, how does noise interfere with fish reproduction? Blom studied the effect of noise on gobies, and she found that “singing is critical to the male’s reproductive success.” She performed an experiment in which one tank of gobies was nice and quiet while the other was exposed to simulated boat noise. Blom found the results to be remarkable:

In the noisy environment, the fish didn’t mate much, and in the few instances they did, it took them longer. What’s more, half of the eggs in the noisy aquariums died without hatching and those that did hatch took longer to do so.

Even if you don’t care about the mating success of gobies, think about the implications of ocean noise pollution on fish stocks. With oceans already becoming more acidic and warmer, noise could be the final straw.

 

Our ocean is a symphony

There’s a new film out that looks at the risks of ocean noise to whales, dolphins, and porpoises, and reveals what scientists and conservationists are doing about it. To read more about the film, click to read this review by John C. Cannon for Mongabay.com. Here’s the mesmerizing trailer:

And in related news: New York City noise threatens new neighbors, endangered whales.

Whales talking on new frequency due to ocean noise

Photo credit: NOAA Photo Library (public domain)

Avery Thompson, Popular Mechanics, reports that “[n]ew research suggests that blue whales are changing their communication band due to noise from human ships.” Thompson writes that noise from ocean liners and large container ships can travel for miles below the waves, disturbing animals like whales and dolphins. Researchers from from Oregon State University are finding that blue whales are learning to adapt to the noise by changing the frequency with which they communicate, and they “believe that the whales are doing this deliberately to avoid interference from human sounds.” Of course, the scientists aren’t completely sure, but as shipping companies move to using quieter electric ships, they will be able to see if the whales go back to their former frequencies.

And it’s not just whales and dolphins that are reacting to ocean noise. Researchers at Newcastle University have discovered that “European sea bass experienced higher stress levels when exposed to the types of piling and drilling sounds made during the construction of offshore structures.”

It’s long past time that humans start considering the harmful effects our noisy existences are having on each other and every other living thing on this planet.

 

Human noise pollution wreaks havoc on U.S. wildlife

Photo credit: USFWS Mountain-Prairie licensed under CC BY 2.0

Rachel Buxton, a postdoctoral research fellow at Colorado State University, writes about the impact expanding transportation networks are having on remote places. Buxton notes that “noise from sources such as vehicle engines is spreading into remote places,” and cautions that “[h]uman-caused noise has consequences for wildlife, entire ecosystems and people.” Buxton and her team conducted a study using “millions of hours of acoustic recordings and sophisticated models to measure human-caused noise in protected areas,” focusing on “human sources of noise in natural environments, such as sounds from aircraft, highways or industrial sources.” The study found that “noise pollution doubled sound energy in many U.S. protected areas, and that noise was encroaching into the furthest reaches of remote areas.”

What are the consequences of these findings? Buxton writes that “[h]uman-caused noise in protected areas interferes with visitors’ experience and alters ecological communities,” adding that “noise may scare away carnivores, resulting in inflated numbers of prey species such as deer.” In addition, although plants can’t hear, they too are affected by noise because “noise changes the distribution of birds, which are important pollinators and seed dispersers.”

The news isn’t all bad, however, as Buxton was “encouraged to find that wilderness areas – places that are preserved in their natural state, without roads or other development – were the quietest protected areas, with near-natural sound levels.”  Unfortunately, the team also found that 12% of “wilderness areas experienced noise that doubled sound energy.”

But all is not lost, as thoughtful management of our protected areas can help to reduce the impact of human-caused noise. Buxton concludes her piece by identifying the strategies that can be implemented to do this, including “establishing quiet zones where visitors are encouraged to quietly enjoy protected area surroundings, and confining noise corridors by aligning airplane flight patterns over roads.”

Humans are changing the underwater soundscapes

 

Photo credit: AWeith licensed under CC BY-SA 4.0

of the world’s oceans. Catherine Rice, Nature World News, reports on how climate change is affecting the world’s oceans. Rice introduces us Kate Stafford, an oceanographer who studies the underwater soundscapes and migratory patterns and geographic variation of marine mammals. Using the Arctic Ocean as an example, Stafford discusses “how climate change is changing the sonic landscape of oceans” and how “human impact on climate could have unknown consequences for marine life which rely on listening to sounds in the ocean for survival.”

Long and short, as sea ice melts it “screeches and cracks and pops and groans, as it collides and rubs when temperature or currents or winds change.” So more melting means more noise. And as the sea ice melts, humans are encouraged “to use bigger ships more frequently” in parts of the Arctic Ocean that previously were not very navigable, which introduces even more loud noise into the soundscape. “Due to warmer waters and less sea ice, Stafford and [other] scientists are seeing other species of whales and mammals moving further north,” which could set up an ugly competition for food.

Rice concludes that “there are still many unanswered questions about the impact of human-induced climate change on the soundscape of the world’s oceans, but it is clear that they are getting noisier.”

Link via @QuietMark.